100 % Renewable Energy Islands
by K. Raghavan Forum for Renewable Energy Islands
Case Study prepared for Inter-regional Advisor, Small Island Developing States, United Nations
and University of West Indies Center for Energy and Development
October 2003 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga”
ACKNOWLEDGEMENTS
This Case Study was carried out primarily because Espen Ronneberg, Inter-regional Advisor, SIDS wanted to investigate the possibility of having a few “100 % Renewable Energy Islands” on SIDS. I am very grateful to him for giving me the opportunity of carrying out this most interesting study that has resulted in positive conclusions for eleven islands in Tuvalu, Fiji and Tonga.
A desk study like this could not have been completed without the co-operation of the many beautiful people from Tuvalu, Fiji and Tonga who took a lot of interest in this study and freely shared information about their islands. My deepest appreciation goes to them for taking time off from their busy schedules to answer my queries.
H.E. Enele Sopoanga’s interest in sustainable energy inspired me to study the islands of Tuvalu. Isaia Taape and Kafuape Lifuka provided a lot of detailed information about the Tuvalan islands and were kind enough to respond to my repeated requests for additional data.
I am grateful to Makareta Sauturaga for spending so much of her valuable time during my visit to her office in Suva, firstly in the selection of the islands and then compiling the data required. Her willingness to share documents available with her and in the OPRET library made it a pleasure to study renewable energy for the Fijian islands. H. Nakatsugawa, the Japanese volunteer working on small hydro power in Fiji, provided good insights and information about utilization of micro-hydro power.
Tevita Tukunga’s straight forward approach and his commitment to renewable energy on the outer islands of Tonga is refreshing. I look forward to working with him to make Niuatoputapu and other islands in the Kingdom of Tonga into 100% RE Islands.
Dr Al Binger, Director UWICED has always provided encouragement and advise in his inimitable style. Many thanks also go to Dr Charles Douglas at UWICED for his comments, suggestions and editorial corrections that have substantially improved the quality of this report and made it more readable.
Anare Matakiviti of SOPAC was very helpful with background information on the Pacific island countries and comments about the study. At SOPAC I would also like to thank Paul Fairburn and Russell Howorth for their views about renewable energy in the Pacific region and their encouragement.
Many other persons who have been working on energy in the Pacific gave useful documents, suggestions and encouragement, notably Thomas Jensen of UNDP- UNESCO at Apia, Coral Passisi and Solomone Fifita of SPREP and Dr Mahendra Kumar of the University of South Pacific.
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CONTENTS
1 EXECUTIVE SUMMARY 8
1.1 Main Findings 8
1.2 Conclusions 11 1.3 Recommendations 12
2 INTRODUCTION 13
2.1 Problem Statement 13
2.2 Rationale for Study 16
3 BACKGROUND 18
3.1 Reports 18
3.2 Overview of 100% RE Initiatives and Programs 20 3.2.1 Samsoe - Denmark’s RE Island 20 3.2.2 Campaign for Take-off 21 3.2.3 El Hierro in the Canary Islands, Spain 21 3.2.4 Similar Studies 22
4 RESULTS AND DISCUSSIONS 23
4.1 Methodology 23
4.2 Energy Efficiency measures 24 4.2.1 Residential 24 4.2.2 Transport 25 4.2.3 Industry 25 4.2.4 Tourism 26 4.2.5 Power generation & distribution 26 4.2.6 Water Production 27
4.3 RE Technologies for Islands 28 4.3.1 Hydro Power 28 4.3.2 Biomass 30 4.3.3 Wind 31 4.3.4 Solar 33 4.3.5 Ocean Energy 33 4.3.6 RE for Transport 34 4.3.7 RE for Water 35
4.4 Other considerations 36 4.4.1 Community involvement 36 4.4.2 Capacity Building & Training 37 4.4.3 Technology Transfer & Local Manufacture 38 4.4.4 Productive Uses of Energy & Income Generation 38
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5 100% RENEWABLE ENERGY ISLANDS ON SIDS 40
5.1 Selection of the Islands 40 5.1.1 Data Collection 41
5.2 Tuvalu 44 5.2.1 Basic Data 44 5.2.2 Land Use 46 5.2.3 Water and Sanitation 47 5.2.4 Present Energy situation 47 5.2.4.1 Electricity Generation 48 5.2.4.2 Cooking and heating 49 5.2.5 Renewable energy resources 50 5.2.5.1 Solar Energy 50 5.2.5.2 Wind Energy 50 5.2.5.3 Hydro power 51 5.2.5.4 Biomass 51 5.2.5.5 Wave power 51 5.2.6 The 100% RE solution 53 5.2.6.1 Energy efficiency 53 5.2.6.2 Coconut oil 53 5.2.6.3 Biogas 55 5.2.6.4 Biomass Gasifiers 56
5.3 Fiji 58 5.3.1 Basic Data 58 5.3.2 Present Energy at Situation 59 5.3.2.1 Fossil Fuels 60 5.3.2.2 Hydro power 60 5.3.2.3 Biomass 61 5.3.2.4 Solar PV and Hybrid Systems 61 5.3.3 Renewable energy resources 62 5.3.3.1 Solar Energy 62 5.3.3.2 Wind Energy 62 5.3.3.3 Hydro power 63 5.3.3.4 Biomass 63 5.3.3.5 Ocean energy 64 5.3.4 The 100% RE solution 64 5.3.4.1 Koro island 64 5.3.4.2 Moala island 66 5.3.4.3 Energy needs 67 5.3.4.4 RE Technologies 67
5.4 Tonga 69 5.4.1 Basic Data 69 5.4.2 Present Energy Situation 71 5.4.3 Niuatoputapu 72 5.4.4 Renewable energy sources 73 5.4.4.1 Solar Energy 73 5.4.4.2 Wind energy 74 5.4.4.3 Hydro power 74 5.4.4.4 Biomass 74 5.4.4.5 Wave energy 74
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5.4.5 The 100% RE solution 75 5.4.5.1 Energy needs 75 5.4.5.2 RE Technologies 75
5.5 Road Map 76 5.6 Obstacles & Remedies 77
5.7 Evaluation Methodology 79
6 CONCLUSIONS 81
6.1 Summary 81 6.1.1 Examples of RE Islands 81 6.1.2 Elements of a “100% RE Island” 82 6.1.2.1 Energy Efficiency 82 6.1.2.2 RE Technologies for Islands 83 6.1.3 “100% RE Islands” on SIDS 83
6.2 Additional Studies 85
7 REFERENCES 86
LIST OF ANNEXURES
Annexure 1 Samsoe − Denmark’s RE Island 88 Annexure 2 Campaign for Take−Off 91 Annexure 3 El Hierro in the Canary Islands, Spain 95 Annexure 4 Five European Islands 98 Annexure 5 Lakshadweep Islands in India 103
LIST OF MAPS
Figure 1 Map of Pacific islands showing location of Tuvalu, Fiji and Tonga 41 Figure 2 Map of the Tuvalu islands 44 Figure 3 Map of Fiji showing locations of Koro and Moala islands 58 Figure 4 Map of Tonga showing location of Niuatoputapu island 69
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LIST OF TABLES
Table 1 The eleven 100% Renewable Energy Islands 12 Table 2 Electricity generation costs (Need to indicate Source) 15 Table 3 Amount and % of energy from RE on Samsoe in 2003 20 Table 4 Targets for energy from RES on 5 islands 22 Table 5 Possible Energy Savings on islands 24 Table 6 Energy used by Tourists 26 Table 7 Size classification of hydel plants 29 Table 8 Biomass Technologies, Sources and Usage 30 Table 9 Classification of Wind Turbine Generators 31 Table 10 Solar Energy Devices 33 Table 11 Techniques to harness ocean energy 34 Table 12 Renewable energy fuels used for transport 34 Table 13 Distillation processes 36 Table 14 RE technologies for local manufacture 38 Table 15 Islands selected for Case Study 40 Table 16 Data Required for planning 100% RE Islands 42 Table 17 Basic Data on Tuvalu islands 45 Table 18 Land use in Tuvalu 46 Table 19 Electricity production statistics for islands of Tuvalu 48 Table 20 Energy demand for a Photovoltaic home in Tuvalu 49 Table 21 Solar, Wind and Weather data for Tuvalu 50 Table 22 Copra production in Tuvalu 51 Table 23 Number of Pigs 55 Table 24 Basic Data on Fiji islands 59 Table 25 Solar, Wind and Weather data for Koro and Moala 62 Table 26 Basic data on Koro island 65 Table 27 Basic data for Moala island 66 Table 28 Basic Data on Tonga 70 Table 29 Solar, Wind and Weather data for Tonga 73 Table 30 Energy Efficiency measures 82 Table 31 RE Technologies and Usage 83 Table 32 The "100% RE Islands" solution 84 Table 33 Technologies for Samsoe’s 100% RE Plan 88 Table 34 Energy Activities in Samsoe’s 10−year RE plan 88 Table 35 Amount and % of energy from RE on Samsoe in 2003 90 Table 36 Campaign for Take−off − 100% RE communities 92 Table 37 RE Partnerships on Islands in the CTO 94 Table 38 Facts about El Hierro 95 Table 39 Annual energy demand 95 Table 40 Energy Savings from Wind−Pumped Hydro system 96 Table 41 Markets Prospects − solar panels on El Hierro 97 Table 42 Yearly targets − solar panels on El Hierro 97 Table 43 Five European Islands 98 Table 44 RES Action Plan for the island of Hiumaa, Estonia 99 Table 45 RES Action Plan for the island of Gotland, Sweden 100 Table 46 RES Action Plan for the island of Lemnos in Greece 101 Table 47 RES Action Plan for the island of Achill in Ireland 102 Table 48 RES Action Plan for the island of Ithaka in Greece 102 Table 49 Power generation and consumption in Lakshadweep 103 Table 50 Coconut Biomass available for electricity generation 104 Table 51 Solar and Wind resource data for Agatti 105
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ABBREVIATIONS
A$ Australian dollar (1 A$ = 0.75 US$) CFL compact fluorescent lamps CHP combined heat and power CTO Campaign for Take-off (a program of the European Union) DOE Department of Energy, Government of Fiji DSM demand side management ED electro-dialysis FEA Fiji Electricity Authority FREI Forum for Renewable Energy Islands ha hectare ITC Technical Institute of the Canary Islands JOCV Japan Overseas Cooperation Volunteers km kilometer kVA kilo volt ampere kW kilowatts (one thousand watts) LPG liquefied petroleum gas mm millimeter MSF multi-stage flash m/s meters per second MW megawatts (one million watts) MW th megawatts thermal OPRET Office for Promotion of Renewable Energy Technologies, Govt. of Fiji OTEC ocean thermal energy conversion PIC Pacific island country PV photo-voltaic PWD Public Works Department RE renewable energy RES renewable energy sources RO reverse osmosis SIDS Small Island Developing States SME small and medium scale enterprises SOPAC South Pacific Applied Geoscience Commission SPV solar photo-voltaic TSREP Tonga Solar Rural Electrification Program T$ Tonga Pa’anga (1 T$ = 0.5 US$) UNDP United Nations Development Program VC vapor compression Wp peak watts (a unit of capacity for SPV modules)
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1 EXECUTIVE SUMMARY
1.1 Main Findings
The main findings of this Case Study are:
1. SIDS continue to rely predominantly on fossil fuels for their energy needs. A review of recent declarations by SIDS shows that, since the Barbados Program of Action was drawn up in 1994, very little progress has been made towards reducing fossil fuel consumption by implementing energy efficiency measures and utilizing renewable energy sources (RES).
2. Proven, reliable and cost-effective technologies are available for eliminating the use of fossil fuels in selected island territories by: a) Reducing energy consumption through rational use of energy and energy efficient devices and techniques. b) Meeting all the energy requirements of selected island territories from RES.
3. There are several examples of islands that have made a plan for achieving 100% RE supply and have made substantial progress towards this goal. Encouragement and support by governments has played a major role in this process. Some islands like Samsoe in Denmark are already producing nearly all the power they consume from RE.
4. The 100% RE movement in Europe clearly shows the catalytic effect of having a few islands make concrete plans to achieve 100% RE status and implement these plans earnestly. The early examples of islands moving towards 100% RE supply has encouraged other islands to make plans to become 100% RE islands. The European Union has put the 100% RE goal into their programs so that funds have been made available to interested islands.
5. There is a lot of interest from government officials of Tuvalu, Fiji and Tonga to transform some of their islands into “100% Renewable Energy Islands”. Consequently, data on energy needs and RE resources has been collected from
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eleven islands in these three SIDS (eight islands from Tuvalu, two from Fiji and one from Tonga).
6. A preliminary study of the data indicates that these eleven islands have sufficient RE resources to meet all their energy needs. The RE technologies that can be used to make these islands “100% Renewable Energy Islands” are proven and reliable, therefore ensuring that they will operate successfully. The following RE technologies are proposed:
a) Coconut oil can be used instead of diesel fuel in diesel power plants and vehicles. Coconut palms are grown on all eleven islands and most of the copra is exported at present. Data from eight islands in Tuvalu indicates that the total quantity of coconut oil that can be produced is 2.1 million liters, of which only 1.4 million liters is required for electricity generation, leaving 0.7 million liters for the transport sector. By using coconut oil instead of diesel, the government will also save money since they are subsidizing copra exports while importing diesel for the power plants.
b) Biogas plants can be used to convert animal and human wastes into gas for cooking and organic fertilizer free of pathogens. Most islanders raise animals, mainly pigs, for domestic use therefore household biogas plants are feasible. Cattle farms and centralized piggeries can use larger biogas plants. This will also facilitate proper disposal of these wastes so that they do not contaminate the ground water resources, which they are doing at present.
c) Biomass gasifiers can convert coconut waste and woody biomass to “producer gas” that can be used in burners for heating. Producer gas can also be used to substitute upto 85% diesel fuel consumption in diesel power plants. The remaining 15% diesel consumption can be substituted with coconut oil. Biomass for gasifiers is available on all the islands.
d) “Run-of-the-river” micro-hydro electric power plants that use water from running streams are feasible on the islands in Fiji. This is one of the best RE solutions since micro-hydels can supply electricity for 24 hours a day with low maintenance costs and no storage requirements. Power can be
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used for lights and domestic appliances in the nighttime and for small industries and other productive uses in the daytime.
e) Improved cook stoves can be used to increase the efficiency of firewood usage and improve air quality in the kitchens on all islands. This will improve the health of the women and children.
f) Solar photovoltaics (SPV) can be used to provide small amounts of power for lighting and telecommunications. Since this is the most expensive RE technology, SPV will only be used as a last option. However, an SPV array can be used in a hybrid configuration with wind turbine generators, battery bank, inverter, control system and back-up diesel gensets to provide a more cost effective solution for locations where the solar and wind resources are complimentary. Coconut oil can be used in the diesel gensets to make the system 100% RE.
7. Several RE technologies can be manufactured locally on SIDS. This will provide employment, create self-sufficiency in RE equipment and ensure that good operation and maintenance capabilities are available locally. Technology transfer for local manufacture of the following RE technologies can easily be arranged: a) Hydro power - Cross-flow and Pelton turbines b) Biomass - Biogas plants, Gasifiers c) Plant Oil - Oil production & modification of diesel engines d) Wind energy - Wind turbine generators, mechanical wind pumps e) Solar energy - Water heaters, driers, cookers, SPV assembly
8. RE power supply can make a substantial improvement in the quality of life on the islands if they are used for productive, income generating activities in the daytime, such as oil presses, handicrafts, weaving, and food processing (fish, dairy, agricultural produce). This will provide employment opportunities on the remote islands and raise the income levels of people, thereby preventing migration to the large urban centers on the main islands. Technical, financial and entrepreneurial skills have to be imparted to local entrepreneurs from the initial stages of the project so that small and cottage industries can come up quickly.
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9. By providing a reliable power supply to hospitals, nursing centers and schools, RE power can help provide improved health and education facilities on the islands.
1.2 Conclusions
1. It is possible to make eleven islands in the south Pacific (eight islands in Tuvalu, two in Fiji and one in Tonga) into “100% Renewable Energy Islands” within a period of 5 to 10 years. Sufficient RE resources exist on these islands and there is a strong interest from governments of these three SIDS. This can be done using a combination of the following RE technologies: a) Coconut oil for diesel power plants, vehicles and boats; b) Biogas from animal and human wastes for cooking gas, organic fertilizer and waste treatment; c) Biomass gasifiers using coconut and woody biomass for heating and diesel power plants; d) Improved cook-stoves to burn wood more efficiently and cleanly for cooking; e) Solar PV and SPV-wind hybrid systems for telecommunications and domestic electricity (lights, radio, TV, fans).
2. These eleven “100% Renewable Energy Islands” on SIDS will demonstrate that it is possible to have a totally sustainable energy supply. They will have a strong symbolic effect and keep the attention of national energy planners and local communities focused on the final goal of sustainable living that is to cease using fossil fuels.
3. These islands will create a catalytic effect and encourage more and more islands to plan and move towards the 100% RE goal. Other islands in these states and on other SIDS will see that 100% RE supply is achievable and will try to plan and implement this sustainable energy model, even though the larger islands may take longer to reach this goal.
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1.3 Recommendations
The main recommendation of this case study is that detailed feasibility studies be carried out on making the eleven islands given in Table 1 into “100% Renewable Energy Islands”:
Table 1 The eleven 100% Renewable Energy Islands # Country Number of Islands Name of Islands 1 Tuvalu 8 Funafuti, Nanumaga, Nanumea, Niutao, Nui, Nukefetau, Nukulaelae, Vaitupu 2 Fiji 2 Koro, Moala 3 Tonga 1 Niuatoputapu TOTAL 11
This should be followed by implementation of the “100% RE Island” plan on the eleven islands. Accordingly, the feasibility studies should produce a document that can be used to obtain funding for the implementation, containing the following: a) Complete details including a time-frame for implementing the “100% RE Islands” plan. b) Technical specifications and costs of all RE equipment to be used. c) Layout of the RE plants and the transmission and distribution grids. d) Logistics of transportation and installation of equipment. e) Operation and maintenance procedures f) Possibilities for technology transfer and local manufacture of RE equipment. g) Possibilities for small and cottage industries to utilize the RE power. h) Roles and responsibilities of all actors - local communities and institutions, government agencies, NGOs, manufacturers and suppliers of equipment, etc. i) Possible funding mechanisms for implementation of the plan. j) Capacity building and training requirements for: · installation, operation and maintenance of the RE systems · local manufacture of equipment · entrepreneurs to start small businesses and industries quickly
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2 INTRODUCTION
2.1 Problem Statement
Energy is absolutely indispensable for development, and the amount required keeps increasing as people desire more and more of the products of modern technology. Development is sustainable only if future generations can continue to enjoy the benefits of development in the way the present generation does. Energy for sustainable development certainly implies the utilization of sources of energy that will not get exhausted leaving future generations without the energy resources that will give them the benefits of development.
Fossil fuels (mainly petroleum, coal and natural gas) that provide us with most of our energy needs were formed deep down under the earth around 50-350 millions years ago due to certain geological conditions. Geologists agree that no new fossil fuels are being produced now. Considering known reserves and the present rates of consumption, it is estimated that the global petroleum reserves will last for another 45–70 years, coal reserves for another 200-500 years and natural gas for another 60 years (Source: Env. Sci., 2002). While these figures can be debated, what is certain is that fossil fuels will get exhausted sooner or later. What will people do after that for their energy needs? When coal, petroleum and natural gas is depleted, it does not require much imagination to predict the situation that future generations will face. From recent examples of power failures over large areas of California, north-eastern United States, Italy, Sweden and Denmark we can see how everything comes to a halt when the electricity supply stops for even a few hours. Present day transportation will also grind to a halt without petroleum products. The only sustainable way out is to utilise the sources of energy at the same speed that earth receives them, or at the same speed that nature creates these secondary energy products, so that the energy used is constantly replenished.
In the final analysis, all energy on earth comes from the sun. Solar energy is the basis of life on earth and of all other forms of energy. The energy from the sun causes the movement of the wind and ocean currents, evaporation of water and rainfall and rivers, plant and animal and human life, which are the causes of the renewable sources of energy like wind, hydro, biomass, ocean, etc. The difference between these sources that makes one form of energy sustainable and the other
______K. Raghavan, FREI Page 13 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” unsustainable is the time required to convert the solar energy that the earth receives everyday into that form of energy. Some of these forms of energy (wind, ocean) are renewed from the sun’s energy within a few hours or days or weeks. Others like the energy in the rivers and lakes (hydro) may take several months to years. Plants (biomass) can take several years to grow. Even these renewable energy sources will not be sustainable if they are used faster than they are produced from the sun’s energy. This is especially important for biomass and we can see many examples of the shortage of firewood for cooking due to excessive deforestation without allowing enough time for the forest cover to regenerate. This unsustainable use of biomass leading to deforestation is also causing serious environmental damage like soil erosion, floods, etc. On the other hand, energy plantations attempt sustainable use of woody biomass by harvesting trees only at the same rate at which they grow.
Fossil fuels are also produced from biomass (plants and animals) but they are an unsustainable energy source because the time required by the natural processes to convert this biomass into coal, petroleum and natural gas is of the order of millions of years and we are using them up much too fast. Burning fossil fuels is also causing a lot of damage to the earth because they produce greenhouse gases, especially carbon dioxide. This is the main cause of global warming that is raising the sea levels, increasing the frequency of extreme events like hurricanes, etc. that have serious negative consequences for small islands.
Another major reason for SIDS to move away from fossil fuels towards RE is that most SIDS do not have their own reserves of coal, petroleum and natural gas. Importing fossil fuels use up a large part of their scarce foreign exchange reserves. Moreover, because SIDS are geographically widely dispersed, fuel transportation costs are high. Sometimes it is very difficult to get transportation companies to supply small isolated outer islands because they do not find it commercially viable. As several recent incidents have shown, there is always the danger of oil tankers breaking up on sea causing enormous damage to marine and coastal life due to pollution of the waters and the seashore.
Considering all the negative aspects of fossil fuel usage and the benefits of using RES one would expect that the whole world would stop using fossil fuels and resort to RES. This has not happened even though technologies for harnessing RE have made tremendous progress particularly over the last 2 decades. In the early stages (1970s and 1980s) many RE technologies were quite new and not technically mature ______K. Raghavan, FREI Page 14 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” enough for remote islands, and many of them failed to work properly. Nowadays most of the basic RE technologies (wind, solar, hydro, biomass) for thermal uses and electricity generation are proven and reliable. However, many RE technologies for transport are still under development, and some of them (e.g. hydrogen) are in the very early stages of commercialisation.
In many of the earlier RE projects operation and maintenance that is crucial for success was not planned well enough. Introducing these technologies in new regions has also proved to be problematic because they require institutional and technical skills, strong political interest, commitment and support that do not exist in many developing countries. Where the right mix of local conditions appropriate to the specific technologies existed, RE technologies they have been very successful. In other locations useful lessons have been learned from failed experiences giving future renewable energy projects brighter chances for success.
Table 2 Electricity generation costs ENERGY SOURCE LIFE CYCLE COST However, the main (US$ cents / kWh) bottleneck preventing the Coal (b) 4 - 5 large-scale introduction of (a) Combined cycle gas turbine 3 - 5 RE technologies is the high Remote diesel generation (a) 20 - 40 costs when compared to Biomass gasification (a) 7 - 9 Wind (a) 5 - 7 conventional power plants (b) Geothermal Energy 7 - 8 using coal or gas. In Small Scale Hydro Power 4 - 8 general RE power plants Solar PV central station (a) 20 - 30 Solar PV distributed (a) 20 - 50 have high initial capital costs (a) (b) Source: Solarbuzz (2003) and DG TREN (2000) but low operation and maintenance costs. Life cycle costs of electricity produced from the main RE resources are compared to fossil fuel power plants in the Table 2. The capital cost of RE technologies depends on the volume of production and on economies of scale. New materials and improvements in manufacturing processes also bring down prices. This can be seen very clearly by the way costs of SPV modules have come down over the last 20 years. The price for high power band (>70 Watts) solar modules has dropped from around US$27/Wp in 1982 to around $ 4/Wp in 2003 (Source: Solarbuzz, 2003).
The cost of electricity from some of the renewable energy power plants (small hydro power, windfarms) is already comparable with conventional fossil fuel power plants.
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Hidden subsidies for fossil fuels prevent a level playing field that would make RE much more competitive. If fossil fuels were penalised for their pollution and green- house gas emissions, many RE options would become commercial choices.
Renewable energy is the only long-term sustainable solution for mankind’s energy needs and has to constitute a larger percentage of our energy supply. Instead of taking a purely commercial point of view, it is important that those of us who believe in RE as the only sustainable solution for our energy needs commit ourselves firmly to promoting RE and push towards maximizing RE utilization and achieving a “fossil fuel free” status. An excellent example of this is Germany, now the leading nation in implementation of RE technologies. German governmental support for RE is phenomenonal. The German “fixed price system” which forms the basis of its “feed- in” law for the purchase of RE power produced by various RES has proved far more successful than the “quota system” practised by several other European countries. Under the “feed-in law”, producers of power from RES are assured of selling their power to the utilities at guaranteed prices that vary with the source. SPV, which is the most expensive RE power, gets higher prices that wind and biomass. The price of electricity from windfarms varies and regions with lower annual average wind speeds get a higher price to compensate for the lower energy production. Consequently, at the start of 2003, Germany had 12,001 MW of wind turbines, the highest in the world (Windicator, 2003). Spain, which also has a “fixed price system” for wind energy is next with 4830 MW and USA comes third with 4645 MW. Together with serious efforts to fulfill their Kyoto Protocol, commitments, the German government has admirably demonstrated, that increased use of RE equipment can create new industries with thousands of jobs and bring down their capital costs.
2.2 Rationale for Study
The advantages of using locally available RES instead of fossil fuels are well known to people in SIDS and some action is already being taken. RE technologies have been implemented in all SIDS regions. However, such projects depend more often on the commercial interests of donor countries than on what is most relevant for the island state or can be replicated in large numbers. Although it is logical that sustainable energy supply must be based on RE, very little progress has been made in this direction by SIDS. This is indicated in deliberations at international conferences and workshops over the last decade. It is therefore important that SIDS
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The goal of any sustainable energy solution is for all SIDS and humanity in general to obtain our energy needs from RES – “100% Renewable Energy Islands”. It is a distant goal – impossible, some would say - but it is the only solution for the future of humanity and the sooner we start working seriously towards it the better. The features of SIDS that make them ideally suited for becoming 100% RE Islands include:
· Geographic isolation and dependence on imported fuels · Highly sensitive ecosystems of substantial economic and cultural value · High capacity to learn how to use new energy technologies, since isolation has developed their ability to respond to emergencies · Energy demand on majority of islands is for the services sector, transport and housing, and only a few islands have energy intensive economic activities · Since RE technologies are modular, they are well adapted to the scales and energy demand found on islands. · Unlike conventional power plants, RE is better suited to dispersed islands since it can be produced in a decentralized way close to the loads. · The abundant RES found on most islands is often sufficient to meet their energy needs, but the potential has not been tapped.
The purpose of this Case Study is to demonstrate how three of the Pacific island states can transform some of their islands into “100% RE Islands”. By implementing the 100% RE Plan on these islands, it is expected that more SIDS will get enthusiastic about having at least one “100% RE Island” to begin with, and make detailed plans on how to eliminate the use of fossil fuels completely on all their islands. If all SIDS have at least one “100% Renewable Energy Island” then this final goal will be constantly in our vision, our actions will get focused on achieving a totally sustainable energy supply and we will reach there sooner.
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3 BACKGROUND
3.1 Reports
The major international meetings focused on sustainable development of SIDS held over the last decade are: 1. UN Conference on Environment & Development (UNCED) held at Rio de Janiero in 1992; 2. Global Conference on the Sustainable Development of Small Island Developing States held at Barbados in 1994; 3. UN General Assembly Special Session in 1999 to review progress on the BPoA after 5 years; 4. Global Conference on Renewable Energy Islands at Aeroe, Denmark in November 1999; 5. AOSIS Preparatory Meeting for WSSD at Singapore in January 2002; 6. World Summit on Sustainable Development (WSSD) at Johannesburg in August- September 2002;
In addition to these international meetings, numerous regional meetings have been held in the Pacific, Caribbean and Indian Ocean regions, many of them preparing for and leading to the major international conferences. All the six major international gatherings listed above specifically addressed the issue of energy for sustainable development.
The ”UN Conference on Environment and Development (UNCED)” at Rio in 1992 was the first major international gathering that focused the world’s attention on energy for sustainable development. The importance of moving away from fossil fuels by more efficient use of energy and increased utilization of RES was stressed, and ways and means of promoting sustainable development were stated clearly in Agenda 21.
However, the first big landmark meeting for SIDS was the “Global Conference on the Sustainable Development of Small Island Developing States” held at Barbados in 1994. For the first time a clearly defined “Program of Action for the Sustainable Development of Small Island Developing States” was drawn up. This Barbados
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Program of Action (BPoA) from 1994 provides a reference point from which progress on all the issues relevant to SIDS including energy can be estimated.
The Declarations at these meetings give an indication of the concerns and the requirements of SIDS in the energy field. While some progress has been made in implementing energy efficiency measures and introducing renewable energy technologies, it is evident from meetings held recently that what has been achieved since 1994 is only a very small part of what still remains to be done on SIDS in these fields. This can be clearly seen by comparing the BPoA of 1994 with, for example, the Agreed Accord of the Pacific Islands Regional Energy Meeting (REM) at Rarotonga, Cook Islands in July 2002, held just before the Johannesburg WSSD.
The 1994 BPoA, section VII on Energy Resources states that: · Small island developing States are currently heavily dependent on imported petroleum products, largely for transport and electricity generation, energy often accounting for more than 12 per cent of imports. …… · ………Increased efficiency through appropriate technology and national energy policies and management measures will reap both financial and environmental benefits for SIDS Several constraints to the large-scale commercial use of renewable energy resources remain, including technology development, investment costs, available indigenous skills and management capabilities. Small-scale application for rural electrification has been sporadic. The use of renewable energy resources as substantial commercial fuels by SIDS is dependent on the development and commercial production of appropriate technologies.
More than seven years later, the Conclusions and Recommendations of the 2002 Pacific Islands Regional Energy Meeting observed that: · Heavy reliance on fossil fuels is still the most critical energy issue in Pacific Island Countries (PICs) and the challenge for them is to pursue an energy path which would reduce their dependence on fossil fuel. Given the country and regional presentations, the meeting noted that both the national and regional effort to reduce the dependence on fossil fuels through RE and energy efficiency interventions have had minimal impacts despite the recognition by the Forum of the benefits of encouraging RE and energy efficiency to advance the reduction of greenhouse gas emissions. (emphasis by author)
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· The meeting noted that the widespread application and the reduction of the implementation costs of renewable energy and energy efficiency technologies are still hampered by a host of institutional, technical, policy, financial, human capacity, awareness and information barriers which are persistent at both the national and regional levels.
The efforts to reduce fossil fuel consumption and increase the use of RE have to yield more substantial results quickly. We need to undertake this task with a greater sense of urgency otherwise we will only make small movements forward. Ten years from now we should have made tremendous progress and not feel as if we are still standing where we now are.
3.2 Overview of 100% RE Initiatives and Programs
3.2.1 Samsoe - Denmark’s RE Island
In 1996 the Danish government had a competition in which islands had to make a plan for reaching 100% renewable energy supply within 10 years. The island of Samsoe won this competition by making the best plan, and started one of the most ambitious programs to become a 100% RE Island within 10 years. The major energy needs of Samsoe are electricity and heat. It was proposed that this would be met from a mix of solar, wind, biomass and waste heat recovery technologies.
Annual plans were made for each of the 10 years. In autumn 2003, at the half-way mark in the 10 year RE plan, most elements of the plan are installed and working, and some of the targets have even been exceeded due to the overwhelming interest of the local population. The percentage of energy consumption that Samsoe gets from renewable energy in 2003 is given in the Table 3. For more details of Samsoe’s RE plan and achievements, please refer to Annexure 1.
Table 3 Amount and % of energy from RE on Samsoe in 2003 Sector Total Demand (million kWh) from RE (million kWh) from RE (%) Heat 58.0 33.2 57.2 % Electricity 26.2 27.0 103.1 % Transport 52.9 75.0* > 100 % * Electricity produced by off-shore windfarm to offset fossil fuels used by the transport sector. Source: SEC, 2003
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3.2.2 Campaign for Take-off
In December 1997 the European Commission adopted a White Paper for a “Community Strategy and Action Plan, Energy for the Future : Renewable Sources of Energy”, which contained the “Campaign for Take-Off” (CTO) as a key element in the strategy. The CTO was planned to run for 5 years (1999-2003) promoting the development of key RES sectors, and aimed for the following: · 1,000,000 PV systems · 15 million m2 solar thermal collectors · 10,000 MW of wind turbine generators
· 10,000 MW th of combined heat and power biomass installations · 1,000,000 dwellings heated by biomass · 1,000 MW of biogas installations · 1,000,000 tons of liquid biofuels · 100 communities aimed at 100% RES supply
The last stated goal of the CTO "100 communities aiming at 100% RES supply” was looked upon as a way to optimize the available potential of renewable energy technologies by using them together in integrated systems for local power supply or in dispersed schemes for regional power supply. A number of pilot communities, regions, cities and islands that can aim for 100% power supply from RES have been identified. These communities differ widely in their energy system characteristics and resource availability, climatic conditions and building styles, size, population density and standard of living. It was found that in newly built communities, the energy infrastructure can easily be designed from the start to accommodate RES, whereas the highly developed energy infrastructure in existing communities can prevent, for many years, major additions of RE into the energy supply system. More details about CTO are given in Annexure 2.
3.2.3 El Hierro in the Canary Islands, Spain
In 1997 the island of El Hierro in the Atlantic prepared a “100% RES Supply Initiative” while declaring its willingness to contribute to the implementation of the CTO. In collaboration with the Technical Institute of the Canary Islands (ITC) it was proposed to meet the electricity demand of the island with 100% RES by 2005 by means of a
______K. Raghavan, FREI Page 21 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” hybrid system consisting of a windfarm with a pumped-hydro using artificial lakes. For a more detailed description of this system please refer to Annexure 3.
El Hierro also has a “zero waste” initiative under which biogas is produced from animal waste and sewage. A 30% reduction of energy consumption by the transport sector is aimed for within 5 years by using several alternative transport systems. Solar thermal systems are being promoted on the island by ITC by means of financial schemes, awareness campaigns, training, involvement of local institutions and population, and the creation of a local company to install and maintain the systems. Bioclimatic solutions and incorporation of RES in buildings is also being tried out. To preserve El Hierro’s Biosphere Reserve status, all the actions of the 100% RES strategy are being integrated with the environmental concerns.
3.2.4 Similar Studies
Table 4 Targets for energy from RES on 5 islands ISLAND 2000 2005 2010 2020 Using a combination of RE Hiiumaa in Estonia 53% 62% 65% 72 % technologies based on wind, Gotland in Sweden 11% 18% 29% 100% solar, biomass, heat pumps Lemnos in Greece 13% 27% 47% 76 % Achill in Ireland - % 9% 28% 110 % and tidal energy, five Ithaka in Greece 10% 46% 79% 118 % European islands have planned targets for energy supply from RES over a 20-year period. The percentage of the energy supply on these islands that will come from RES is summarized in Table 4. A description of these islands and details of their RE programs are given in Annexure 4.
Nine Indian islands of the Lakshadweep group in the Arabian Sea have prepared a 100% RE Plan using a combination of solar, wind and biomass technologies, details of which are given in Annexure 5.
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4 RESULTS AND DISCUSSIONS
4.1 Methodology
This Case Study is the first step in the process of having a totally sustainable energy supply on some islands.. It is essentially a Pre-feasibility Study for 100% RE supply on eleven islands in three SIDS in the Pacific. The methodology followed in this Case Study can be divided into two main parts:
1. Study the main elements of a totally sustainable energy solution for islands in general that will enable them to become “100% Renewable Energy Islands”. These can be grouped into 2 types of actions: · Use energy more efficiently in order to bring down energy consumption as far as possible while people enjoy the same benefits as before. · Use RES to substitute for fossil fuels.
2. Select suitable islands and outline a strategy that can make these islands into “100% Renewable Energy Islands”. This consists of the following actions: · Select the islands. · For the selected Islands collect data on - Energy needs - Present power supply - Renewable energy resources · Identify main elements of the sustainable energy solution. · Recommend future actions to make them into “100% RE islands”.
The first part of the methodology in Section 4 gives details of the various methods and technologies used to implement energy efficiency and renewable energy. Section 5 explains how the islands were selected, presents data collected about the selected islands and outlines a strategy by which they can attain an energy supply only from RES.
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4.2 Energy Efficiency measures
Table 5 Possible Energy Savings on islands # ENERGY % of TOTAL ENERGY The energy needs of an island USAGE ENERGY SAVINGS society can be met with much CONSUMED POSSIBLE 1 Water, Heat, 10 – 20 % 30 % less energy use, so the first AC imperative is to increase the 2 Transport 50 – 60 % 60 % overall efficiency of energy 3 Electricity 30 % 40 % TOTAL 100 % 50 % usage. It is possible to reduce energy consumption by around 50% through the implementation of measures for energy efficiency and the rational use of energy.
The main sectors in which energy savings are possible on islands by means of rational use of energy and energy efficiency measures are: 1. Residential 2. Transport 3. Industry 4. Tourism 5. Power distribution 6. Water production
4.2.1 Residential
Heating and cooling of buildings on islands uses up about 15 - 20% of the total energy consumed. This consists of around 30 - 40% of electricity production and 10 - 15% of other energy sources (coal, gas, fuel-oil). Simple energy audits can help realize the potential for energy savings in buildings. Less energy can be used for lighting, heating and cooling, by means of: · compact fluorescent lamps (CFL) · energy efficient refrigerators · insulating windows in winter · special window glazing in summer · bio-climatic concepts · zone heating & cooling
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4.2.2 Transport
Modern technologies have greatly improved the efficiency of vehicles used for land, sea and air transport. One of the main problems on many islands is the availability of cheap used cars and buses that are highly fuel inefficient. These vehicles are procured at low prices from developed economies such as Japan, Europe and North America. Government policy and regulations have to prevent the import of fuel inefficient vehicles because that is an effective method of reducing fossil fuel consumption and the harmful environmental effects of their emissions. Vehicles that run on RE fuels or can easily be converted to run on RE fuels should be encouraged and given financial incentives.
There is a large potential to optimize transportation, especially public transportation. Methods to do this that have been demonstrated successfully in various parts of the world include: 1. Urban planning will prevent traffic jams and allow traffic to move faster. 2. Good public transport, especially Mass Rapid Transit (MRT) systems will encourage people not to use private cars. 3. Fast lanes for pooled cars carrying at least 3 passengers will encourage people to share cars, especially during rush hours. 4. Fast, dedicated lanes for buses have been very successful in Bogota, Colombia and other cities. During rush hour traffic jams, cars move slowly but the busses have their own lanes and can drive fast. 5. Cycle lanes that make it safe and comfortable to ride cycles will encourage people to cycle more instead of driving cars.
4.2.3 Industry
Energy efficient devices and waste heat recovery equipment in industries can reduce overall energy consumption considerably and make good financial propositions since they can sometimes have pay-back periods of one year or even less. Energy efficiency techniques in industry include: · Recent advances in boiler and furnace technologies allow their operation at higher temperatures, so that they use less energy and also give off less harmful emissions to the atmosphere
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· With the dramatic decrease in the cost of microprocessors, modern controllers and variable speed drives allow more efficient operation of motors, which are widely used in industries for pumps, blowers, fans, compressors, etc. · By recovering waste heat from industrial processes and equipment, the overall efficiencies of energy usage can be increased. The heat recovered can be used for thermal applications or for generating electricity or for both as in combined heat and power (CHP) plants.
4.2.4 Tourism
In islands where tourism is a major source of livelihood, the energy demand of the tourist sector can be as high as 40% of the total energy excluding transport. The main uses of energy on islands by tourists are given in Table 6. On some of the tourist islands, at the height of the tourist season, the number of tourists can outnumber the local population by a factor of four or more. If the season is only for a part of the year there will be a very high energy consumption only during several months. This can require power generation equipment that is highly oversized for the rest of the year when much less energy is required by the local population
Table 6 Energy used by Tourists Energy Usage at % of Total Increasingly more tourists are being attracted Tourist Centers Energy by the “eco-labels” being used by hotels and Water, Heat, AC 65 - 75 % Cooking 15 - 20 % tourist centers to promote their image as an Lighting 5 - 10 % environment friendly destination. RE and Other 5 % alternative silent and non-polluting transport can improve the tourist destination’s quality and can even be used to turn it into a new attraction. This will also have a very high demonstration value since millions of tourists spend their holidays on islands each year.
4.2.5 Power generation & distribution
There are two ways to produce the energy needed by the population on islands: · Centralised energy production in which one or more large power plants produce most of the energy requirements (electricity and heat). The power is distributed by means of an electrical grid or network of insulated pipes;
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· Decentralised energy production in which energy is produced by a number of small power plants close to where it is used. No central distribution network is present but small, decentralized mini-grids distribute the power.
We also find a combination of centralised and decentralized systems on many islands. The central grid supplies only the urban population centers while the rural areas have their own small power generation systems, or maybe they do not have any power at all.
In contrast to large, centralized fossil fuel power plants based on coal or gas, most RE power plants are smaller and offer a decentralized solution. Producing power close to the load center results in lower power losses during transmission and distribution. Decentralised power also avoids long, high capacity transmission lines thereby decreasing the initial capital costs.
Storage is quite easily incorporated into RE power plants in the form of batteries, flywheels, pumped-hydro, etc. This can help even out the fluctuations in the demand without expensive capacity addition. Demand side management (DSM) practices can also be used to cut down the peak loads and therefore reduce the maximum generation capacity of the power plants and the capital costs. Preferential tariffs are one of several ways to encourage people to use more power during off-peak hours.
4.2.6 Water Production
Energy is required to purify and pump water, and also for desalination if the supply of fresh water is not sufficient. For islands with a high tourist population, water availability is directly linked to energy availability and is a key factor in development of the tourist sector on the island. The need for water shortage is due to a variety of reasons: · Low rainfall · High tourist population that is too much for the local water production capacity. · Inefficient use of water resources. · Distribution losses can sometimes be as high as 40%.
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While additional requirements for fresh water can come from desalination, a sustainable water policy must include integral water management that utilizes water optimally. Waste-water should be treated and recycled for agricultural use, and the final wastes disposed of properly to minimize negative environmental impact.
4.3 RE Technologies for Islands
The main RE resources for islands are: · Solar · Hydro · Biomass · Wind · Ocean Technologies for utilizing these resources are briefly described in the following sections.
In selecting appropriate RE technologies for meeting the energy demands of Islands several considerations are important. Technical maturity is very important since failed projects are a waste and resources, and give a bad name to RE. In general the following are critical considerations: · Reliability of systems is more important than efficiency · Possibility of local manufacture of equipment · Suitability to local conditions · Ease of installation, operation & maintenance · Costs
A vast majority of islands are electrically isolated from the mainland while a few are interconnected to the mainland grid. In small autonomous islands special attention has to be paid to system stability and reliability by choosing the right mix of RE technologies, control systems and energy storage.
4.3.1 Hydro Power
Hydro power makes use of the energy of water in a stream or lake. The water is taken through a canal or pipeline to turn a hydraulic turbine that drives a generator or
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Table 7 Size classification of hydel plants # NAME SIZE RANGE UNITS Hydro power plants have an inherent 1 Pico hydro < 5 kW advantage over other RE 2 Micro hydro 5 – 100 kW 3 Mini hydro 0.1 – 3 MW technologies such as SPV or off-grid 4 Small hydro 3 – 15 MW wind power, since they can give 5 Large hydro > 15 MW fairly inexpensive power for 24 hours a day with no additional storage such as batteries, etc. Power in the daytime can be used for small industries and in the night for lights, etc. This is an important consideration for islands where employment opportunities and income generation from the productive uses of the energy in the daytime forms an essential part of the development process.
There are basically three types of hydro electric schemes: · Run of the River · With Storage (diurnal, seasonal or annual storage) · Pumped Storage
Run-of-the-river hydro power plants use the running water from a stream or river and put it back into the river after the power plant. Only a small amount of water is stored in the forebay to take care of short-term power demand fluctuations of the order of a few minutes. Since there are no large dams or reservoirs, this is the most environmentally friendly way to use small hydro power.
Hydro schemes with storage can store enough water to cover fluctuations in the stream flow over one day (diurnal), over a season (seasonal) or over one whole year (annual). If there is a wide variation in annual rainfall, large storage can store water from one year with very high rainfall onto another year with low rainfall. Big dams or reservoirs are best avoided since the lakes of large dams submerge huge areas of land causing large-scale displacement of population in addition to serious environmental impacts.
Pumped storage is used to store energy from another RES such as wind power. Wind electricity produced during periods of high wind speeds can be used to pump water from a lower reservoir to an elevated reservoir. This water can be used to
______K. Raghavan, FREI Page 29 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” drive the turbines in a hydel plant whenever electricity is needed, and then flows back into the lower reservoir. A pumped hydro storage with a 15 MW windfarm is being planned on the island of El Hierro in the Canary Islands. (please refer to Annexure 3 for more details).
4.3.2 Biomass
All plant and animal life produces biomass in its various forms. Sources of biomass and the technologies that convert the biomass into forms of energy for a variety of end uses are summarized in the Table 8.
Table 8 Biomass Technologies, Sources and Usage # TECHNOLOGY SOURCE USAGE 1 Combustion Wood Heat Agricultural residues Steam (electricity) 2 Gasifiers Wood chips, sawdust Thermal Agricultural residues- straw, Shaft Power rice husk, groundnut shells Electricity 3 Anaerobic Animal and human wastes from Cooking & Heating Digestors farms & households Lights (Biogas) Municipal Solid Waste from Shaft Power landfills Electricity 4 Biofuels Sugar cane, mollases Ethanol Grains, sugar beet Pure Plant Oil Oil seeds Bio Diesel
Direct combustion of woody biomass or agricultural residues like straw produces heat that can either be used directly or in a boiler to make steam. Steam is a versatile source of energy with various applications including steam turbines to generate electricity.
Combustion also takes place in a gasifier but under a controlled supply of air resulting in “producer gas” that can either be burned for heat or burned in a diesel engine to produce shaft power or electricity. Gasifier-diesel engine systems work in a “dual fuel” mode with the producer gas substituting around 80 – 85% of the diesel used. To use 100% producer gas in engines, a spark plug is necessary for ignition.
Bio-degradable biomass like animal and human waste can be used in an anaerobic digestor in the presence of methanogenic bacteria to produce biogas which is a mixture of methane and carbon dioxide. Biogas can be burned for heat or light, or it
______K. Raghavan, FREI Page 30 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” can be used instead of diesel in an engine to generate shaft power for pumping water, driving machinery or generating electricity.
Liquid fuels from biomass fall broadly under two categories – alcohols and plant oils. Ethyl alcohol (ethanol) can be produced from sugarcane and its by-products (molasses, etc.), sugar beet and grains. Ethanol can be blended with petrol and used in vehicles, which has been done in Brazil for many years. Pure plant oils can be produced from coconuts, oil palms and oil seeds. Most oil seeds like rape seed, mustard, ground nut, olive and sesame produce edible oil but there are a few non- edible oil seeds like jathropa and pongam. Pure plant oils can be used instead of diesel after making minor modifications to the diesel engine. Plant oil is a very good fuel for local production and usage – farmers can grow the oil seeds, use small oil presses to extract the oil, use the oil to run their tractors and use the oil-cake to feed the animals.
Bio-diesel is produced from plant oils by a process of esterification. The only advantage of bio-diesel over plant oil is that it can be used in ordinary diesel engines without any modification to the engine. The disadvantage is that nearly 26% of the energy in biodiesel has been used to produce it whereas for pure plant oil the energy used to produce it is only 13%.
4.3.3 Wind
The energy from wind can be used to turn the rotor blades of a wind turbine. The mechanical shaft power of the wind turbine has been used directly, for nearly a century, to grind flour and pump water. Windmills are not used for grinding flour any longer but mechanical windpumps are still widely used for pumping water. Windpumps can be an appropriate solution for some islands especially since they can easily be manufactured locally. Wind turbines can also be connected to a generator (directly or through a gear box) to produce electricity. The types of wind generators, their applications and capacities are given in the Table 9.
Table 9 Classification of Wind Turbine Generators # SIZE APPLICATION GENERATOR CAPACITY 1 Small Stand Alone, Off-grid Permanent Magnet Alternator < 50 kW 2 Medium Wind-Diesel Induction (Asynchronous), 50 - 500 kW Multi-pole 3 Large Grid Connected Induction, Multi-pole 0.5 – 5 MW ______K. Raghavan, FREI Page 31 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga”
Small and medium sized wind turbines have good application possibilities on islands with sufficient wind speeds for pumping water and generating electricity. Small wind turbine generators for off-grid, stand-alone applications are meant for villages and communities with no electricity. Stand-alone wind systems normally incorporate a voltage control system, battery bank and inverter, and can easily be combined with solar photovoltaic arrays to give a “wind-solar hybrid” system. Such hybrid systems are more cost-effective in places having complementary wind and solar resources, i.e. high wind speeds and low solar radiation during some months of the year, and low wind with high solar during other months. Small wind generators can also be used in a “wind electric pumping system” directly for pumping water without a battery bank. Wind electric pumps have two advantages over mechanical windpumps – (a) they are more efficient and (b) they do not have to be installed directly over the water source and can therefore be sited more optimally.
Medium sized wind turbines in the 50 to 500 kW range can be used with diesel grids to reduce diesel fuel consumption. Such “wind-diesel hybrid systems” have microprocessor based control systems that can turn off all the diesel generating sets during high wind speeds to effect maximum diesel savings. Tilt-up towers allow easy installation of these wind turbines without cranes making them ideally suited for islands with limited infrastructure. These towers also make it possible to lower the wind turbines quickly during cyclones and hurricanes, or for maintenance purposes. Excess wind power during periods of high wind speeds can be diverted to low priority loads that have inherent storage possibilities like water pumping, ice making or heating.
Large wind turbines require very good infrastructure (roads, cranes, electricity grid) for transport to site, installation, operation and maintenance. A modern, 4.2 megawatt wind turbine has a rotor diameter of 110 meters, its nacelle weighs 145 tons and the rotor blades weigh 69 tons. These huge turbines can be installed and perform well in large mainland grids but are not suitable for most islands where only limited infrastructure is available.
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4.3.4 Solar
Solar energy can be used for the heat it provides or it can be converted directly to electricity in photovoltaic cells. The main solar energy devices for heat and electricity are listed in Table 10. For both applications, solar energy can be concentrated by means of flat or curved (parabolic) reflectors.
Table 10 Solar Energy Devices THERMAL PHOTO VOLTAIC · Water Heaters · Lanterns · Cookers · Home Lighting Systems · Driers · Power Plants · Space heating · Pumps · Desalination (MSF, VC) · Desalination (ED, RO) · Solar ponds · Furnaces, crematoriums
Technologies for both solar thermal and photovoltaic (SPV) are mature, and the products are reliable. Solar thermal applications like water heaters, driers, and cookers are quite cost-effective. On the other hand, SPV continues to be one of the most expensive RE options for electrification in spite of significant cost reductions over the last 20 years. Moreover SPV systems require a battery bank for storage. This is a major dis-advantage since lead-acid batteries can cost around one-third of the system cost, will only last for 5 to 8 years, and can harm the environment if they are not disposed properly or recycled. SPV has proved to be very reliable and successful in supplying small amounts of power for niche applications like lighting in remote communities having no other options, telecommunications, etc. However, it is impossible to consider SPV power for small and medium scale enterprises for productive uses of the power because the costs are prohibitive.
4.3.5 Ocean Energy
There are three main types of ocean energy that can be harnessed for power: · Ocean Thermal Energy Conversion - OTEC · Wave Power · Tidal Power The different techniques used to convert these types of ocean energy are listed in Table 11.
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Table 11 Techniques to harness ocean energy OTEC – Ocean Thermal WAVE Power TIDAL Power Energy Conversion · Closed cycle (sea water) · Floats, pitching, rolling · Dam + Low head · Open cycle (working fluid) · Oscillating Water Column turbines · Hybrid (sea water + · Over topping, surge · Increases silting working fluid) by slowing tides
One big advantage of some OTEC systems is that they can provide fresh water in addition to power. However, most of the technologies for conversion of ocean energy are still in the research and development stage and some are in the early stages of commercialization. Therefore, one has to be very careful while introducing these technologies on islands, where one would like to be very sure about the reliability and success.
4.3.6 RE for Transport
The transport sector is the most difficult to convert to 100% RES. Renewable energy fuels commonly used in the transportation sector are given n the Table 12, together with how they are used and some of the main advantages and dis-advantages of each fuel.
Table 12 Renewable energy fuels used for transport RE FUEL SOURCE USAGE REMARKS Pure plant Pressing Oil Seeds · Instead of diesel in · Local production oil – (rape seed, engines and usage increases coconuts, jathropa, self-sufficiency pongam, etc.) · Minor modifications have to be made in diesel engines Biodiesel Esterification of · Instead of diesel in · No modifications Plant oils engines required in diesel engines · Present supply & distribution infra- structure can be used · Less harmful to environment Hydrogen Electrolysis of · Fuel cells + · Electricity must water Electric car come from RES · Direct combustion · Not yet in petrol engine of commercialized car · Supply & ______K. Raghavan, FREI Page 34 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga”
RE FUEL SOURCE USAGE REMARKS Distribution infrastructure not in place Producer Gasification of · Substitutes upto · 15-20% diesel fuel gas biomass 85% diesel In required for ignition engines · Well suited for stationary diesel power plants · Gas has to be purified and compressed for storage on vehicles Biogas Anaerobic · Substitutes upto Same as above remarks digestion of 85% diesel In for Producer Gas biomass engines Electric Electricity to · Electric motors · Electricity must cars charge batteries drive wheels come from RES · Not suited for long distances · Costs very high since batteries last only 3-4 years
Biogas and producer gas can be used in vehicles in a dual-fuel mode to substitute upto 85% of diesel fuel. The gases can be purified and compressed but storage of the gases is still a limitation for vehicles. However, the liquid fuels from biomass are excellent renewable fuels. Ethanol can be used in petrol engines while pure plant oil and biodiesel can be used in diesel engines.
4.3.7 RE for Water
Seawater desalination techniques can be based on distillation or membrane processes both of which can use either heat or electricity. The equipment used for desalination based on RE is, in most cases, the same equipment used on conventional sources of power supply on the mainland or on ships. Exceptions are low-cost, appropriate technologies like solar stills that distill water directly using solar radiation. While solar stills are good for small-scale, local production of water, they require large areas of land for big desalination plants.
All the techniques used in distillation or membrane processes consume a lot of energy. Production of one cubic meter of fresh water uses over 10 kWh in
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Table 13 Distillation processes PROCESS EXAMPLES Thermal Processes (distillation) MSF - Multi-Stage Flash heat salt water and condense the MED - Multi-Effect Distillation vapour. VC - Vapour Compression Membrane Processes ED - Electrodialysis (voltage-driven process) use the ability of membranes to RO - Reverse Osmosis (pressure-driven process) separate salts from water.
4.4 Other considerations
There are several other important considerations in planning a sustainable energy supply. Sufficient attention to these matters will not only allow the local population to feel a sense of involvement and self-confidence that they can improve their own future, but will also address the developmental aspects of energy usage and thereby improve the quality of their lives from the initial stages of the project.
4.4.1 Community involvement
Instead of a top-down approach in which the government puts up an energy project for the people it is far better to take a bottoms-up approach in which the local community is involved in the process from the beginning. The community should decide how they would like to improve the quality of their lives and what is required to do it. They should feel an increasing level of self-confidence that they can determine their own destiny and help themselves. Some external assistance will be required in the beginning and the later stages, but it should not be an energy supply system just handed down to them. If the community feels that they decided what kind of energy supply system is best for them, and they participated in the installation, operation and maintenance, then they will treat the system as their own, will care for it and ensure that it is a success.
Awareness campaigns are very effective to inform the community about the benefits of energy efficiency measures and RE technologies. People can be taught how to carry out energy audits in their houses to optimize energy consumption of equipment
______K. Raghavan, FREI Page 36 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” like lights, refrigerators, water heaters, etc., and how to reduce energy for heating and cooling of buildings by use of insulation, double glazed windows, sun screens, etc. The environmental and economic benefits of using RES can be explained and demonstrated so that the local population gets enthusiastic about the RE systems they select and install.
In addition to the direct energy requirements of the people (lighting, cooking, heating, cooling) the developmental needs of the local population have to be taken into account from the beginning, so that the benefits for the community are experienced quickly and the quality of their lives can be improved from the initial stages of the project. The real needs of the people have to be addressed and their priorities have to be considered while deciding what they should get first.
4.4.2 Capacity Building & Training
Local capacity has to be strengthened so that all aspects of the energy planning, production, distribution and use can be handled effectively by in-country manpower. Energy offices on islands have played a key role in the planning and implementation of RE projects and such offices should be created on islands where they do not exist. By means of awareness campaigns and regular meetings, the energy office can ensure a close involvement of the local community at all stages.
Training will form an important part of building capacity, especially in the planning, installation, operation and maintenance of the RE Systems. Such tranining may be imparted at manufacturers’ facilities, on existing RE projects and during installation of the systems. Project management capabilities, both technical and financial, may have to be built up or up-graded. .Human resource development is an on-going process and should be continued right through the implementation of the 100% RE plan as new skills need to be acquired or fresh manpower trained. For the specific capacity building and training needs to plan and implement the “100% Renewable Energy Islands”, national or regional RE training centers may have to be strengthened or set up if they do not exist already.
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4.4.3 Technology Transfer & Local Manufacture
Many of the RE technologies are well suited for local manufacture on SIDS, as shown in Table 14. This is good for the local economy, since it creates employment and makes SIDS self sufficient in RE equipment. Some of the RE equipment require only a good mechanical workshop that is found on most of the SIDS, though it may need some additional machinery and training of operators.
Table 14 RE technologies for local manufacture RE source Technologies A technology transfer Hydro power · Cross-flow turbines arrangement should include · Pelton turbines complete technical know-how, Biomass · Biogas plants · Gasifiers training in the manufacturing · Plant Oil production & usage processes, installation, Wind energy · Electric generators operation and maintenance. · Mechanical windpumps Quality assurance is vital for Solar energy · Heaters · Driers success and has to be instilled · Cookers in the local company. Some of · SPV assembly the technologies may have to be manufactured on a regional scale to ensure financially viable production volumes.
4.4.4 Productive Uses of Energy & Income Generation
On some of the islands being considered in this Case Study, there is no electricity supply at present while others have some SPV for lighting or diesel gensets. Islands with power from diesel gensets very often supply electricity only for a few hours in the evening because it is very expensive. On all these islands, the power is used for lighting, TV and domestic appliances. The growth of small and medium scale enterprises (SMEs) has been restricted by this lack of a reliable and affordable power supply during the daytime.
Experiences from many parts of the world show that when power from RE is made available in the daytime local enterprises that can use this power come up very slowly because the necessary business skills and confidence are lacking. This time lag can be eliminated if the growth of the SMEs is planned simultaneously with the RE power supply. Moreover, the utilization of power in the daytime improves the viability of the RE power plant itself by increasing the capacity utilization factor.
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SMEs that use RE productively are very important for the development of the island. They provide employment opportunities and income generation that are crucial for improving the quality of lives of the people. Once people have money to spend, a lot of other things come up naturally to provide them with the things that they want. Stimulating the growth of SMEs quickly will form an important part of the 100% RE Island plan. Assistance to start SMEs and household industries and to run them successfully will have to be provided to the local population in several key areas:
· Selecting viable enterprises · Preparing business plans · Getting financial support from banks & govt. agencies · Procuring equipment and operating them · Marketing the products · Managing a small enterprise
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5 100% RENEWABLE ENERGY ISLANDS ON SIDS
5.1 Selection of the Islands
The islands in this Case Study were identified after contacting Energy Officials of SIDS to determine their interest in making some of their islands “100% Renewable Energy Islands”. This was done through correspondence and personal discussions during and after the presentation of this Case Study at the Energy Experts Meeting held on Niue in July 2003. One or more small islands in the interested SIDS were then selected based on the following criteria: 1. The island should be small with a population of around 1,000 or less. This will serve the purpose of this show-case demonstration project whilst making it easier to secure funds for the implementation of the 100% RE plan, since the total funds required for the RE equipment will be modest. 2. The island should either have no power supply at present or it should have a diesel power plant that provides power only for a few hours in a day. This project can then benefit people who have a maximum need for power supply in the country. 3. There should be preliminary evidence of sufficient renewable energy sources, preferably hydro power or biomass, which can provide power in the daytime for productive uses without the need for additional storage like batteries. 4. There should be possibilities of productive, income generating activities on the island that can use the RE power, so that development benefits of the power can quickly improve the lives of the people.
Officials from the governments of Tuvalu, Fiji and Tonga have expressed interest in making one or more or their islands into “100% Renewable Energy Islands”. A total of eleven islands in these three Pacific island states have been selected for this Case Study, whose names are given in the Table 15.
Table 15 Islands selected for Case Study # Country Number of Name of Islands Islands 1 Tuvalu 8 Funafuti, Nanumaga, Nanumea, Niutao, Nui, Nukefetau, Nukulaelae, Vaitupu 2 Fiji 2 Koro, Moala 3 Tonga 1 Niuatoputapu TOTAL 11
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Officials from Papua New Guinea, Comoros and the Marshall Islands have also expressed interest in making some of their islands into “100% Renewable Energy Islands”. Information about their islands is still awaited and these will be included in the Case Study as soon as the minimum data required is made available.
Figure 1 Map of Pacific islands showing location of Tuvalu, Fiji and Tonga
5.1.1 Data Collection
This Case Study is a desk study and only data provided by the officials of SIDS or available in the public domain has been used. The data that we tried to get on the selected islands is given in Table 16. It is a long and exhaustive list, and many items are either not applicable or not available for the islands selected for this study.
Any data that can only be collected during site visits or has to be measured falls outside the scope of this study. Such data will be collected during the Detailed Feasibility Study that will follow this case study.
.
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Table 16 Data Required for planning 100% RE Islands # HEADING DATA ITEM 1 LOADS Daily or Monthly average values or Time Series (hourly / 10 minute averages) a) Present loads in kW - max, min, average b) Present energy consumption in kWh/day, c) Projected increase in loads over the next 10 years For types of loads: a) Electricity b) Heating c) Cooling d) Pumping e) Others (specify) 2 EXISTING General info for all options (DG, hydel, biomass, wind, solar) POWER a) Map of island with location of power plants, loads, T&D lines SUPPLY b) Initial investment costs - power plants and T&D c) Operation and maintenance costs d) Cost of generation e) Price paid by consumers for electricity f) Experiences with diesel and RE power plants Diesel power plants a) Capacity and number of diesel gensets b) Hours of operation and average output (kW, kVA, power factor) c) Landed cost of diesel fuel d) Price of diesel electricity e) Transmission - step-up and step-down transformers, f) Distribution - voltage and length of lines Hydro-electric power plants a) Schematic of hydel plant b) Year of installation c) Details of diversion weir and desilting basin d) Power canal - construction, width, depth, length e) Penstock - material, diameter, length f) Turbines - type, rated head, flow & capacity g) Generators - rated capacity (kW, kVA) h) Transmission - step-up and step-down transformers, i) Distribution - voltage and length of lines j) Cost of hydel plant, and T&D Hydro power - shaft power for flour milling, oil expellers, saw mills, etc. a) Approximate capacity in kW b) Head and flow used c) Number of installations Solar PhotoVoltaic (SPV) a) Solar lanterns b) SPV Home Lighting Systems c) SPV power plants d) SPV pumping systems e) Others Solar Thermal a) Water heaters b) Cookers c) Driers d) Space heating e) Others ?? Wind Energy a) Stand-alone (off grid) wind generators b) Grid connected wind generators / wind farms c) Mechanical windpumps d) Others Biomass
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# HEADING DATA ITEM a) Biogas plants b) Biomass gasifiers c) Others Other renewables a) Ocean energy - OTEC, wave power, tidal power b) Geothermal c) Any others ?? 3 RENEWABLE Hydro power ENERGY a) Map showing streams & rivers, elevations of mountains, if available RESOURCES b) Topographical map showing contour lines, if available DATA c) Stream flow measurements d) Rainfall data
Wind Energy a) Map showing location and heights of wind monitoring stations b) Location and heights of buildings, trees and other wind barriers near the windmasts c) Instruments used d) Wind speeds, directions e) Temperature and pressure (OR air density)
Solar radiation a) Map showing location of measurement stations and obstructions that shade the instruments, if any (buildings, trees, etc.) b) Instruments used c) Global radiation (kWh / day) d) Direct (beam) & Diffuse radiation
Biomass a) Types of biomass available and quantities b) Cost of collection and supply at usage site c) Present usage and quantities used Other renewables a) Geothermal b) Wave power c) Ocean Thermal Energy d) Tidal Power
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5.2 Tuvalu
5.2.1 Basic Data
Figure 2 Map of the Tuvalu islands
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Table 17 Basic Data on Tuvalu islands Capital Funafuti Population 9,600(1999 est.) Land Area 26 km2 Max. Height Approximately 5m Above Sea Level Geography Consists of 5 atolls and 4 coral islands; the 9 islands are Vaitupu, Funafuti, Nanumea, Nanumaga, Niutao, Nui, Nukufetau, Nukulaelae, and Niulakita. EEZ 1.3 million km2 Climate Tropical; marine, hot and humid, moderated by trade winds. Rainfall Varies considerably with an average of 3000 mm per annum. Mean 30 0C Temperature Economy Mixed market-subsistence economy and also reliant on aid; exports include copra, handicrafts and philatelic stamps. agriculture & fishing GDP Per Capita US$1,157 (1998 est.) Currency AU$ Energy Sources Biomass, solar, wind Freshwater Rainwater, groundwater, desalination Sources Natural Hazards Cyclone, coastal flooding, tsunami, storm surge, drought, earthquake, landslide, erosion, saltwater intrusion Mineral On-land - unknown; Offshore-cobalt-rich manganese crusts Potential Languages Tuvaluan and English Government Independent state and associate member of Commonwealth Source: Sopac (2002a)
Tuvalu consists of 9 island groups whose capital is Funafuti and the main educational and agricultural centre is Vaitupu. The islands lie between 5 and 11 degrees south of the equator. Even though the total land area is only 26 km2, the exclusive economic zone of the archipelago is 1.3 million km2. Since the islands are small and geographically separated the population in mid-2002 was 10,100 and Tuvalu has one of the highest population densities in the Pacific at 388 persons per km2. The climate is sub-tropical with temperatures ranging from 28 to 36 C. The mean rainfall varies from 2,700 to 3,500 mm per year on the islands and there are no wet or dry seasons. Because of its low elevation above sea level, Tuvalu is extremely vulnerable to storm surges and there is a lot of concern about the effects of rising sea-levels.
International aid plays an important role in the economy of Tuvalu and tourism has a small role, but a majority of the population live on subsistence activities, mainly agriculture and fishing. Depletion of natural resources is a major problem including
______K. Raghavan, FREI Page 45 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” over fishing on the reefs and over-exploitation of the trees for cooking fuel; consequently, the Funafuti town council now prohibits cutting trees for fuel wood,
5.2.2 Land Use
The land use in Tuvalu is given in the Table 18. Coconut palms cover nearly 54% of the land area, while mangroves rank second covering around 17%.
Table 18 Land use in Tuvalu Type of vegetation Area (ha) Percentage The 1,800 ha of Coconut woodland 1,619 53.9 agricultural land is Broadleaf woodland 122 4.1 divided unequally Coconut & broadleaf woodland 51 1.7 Scrub 419 13.9 among the 9 islands Pandanus 10 0.3 with 520 ha on the Mangroves 515 17.1 largest island, 42 ha Pulaka pits & pulaka basins 65 2.2 on the smallest, and Village, buildings 172 5.7 Others (i.e. low ground cover) 33 1.1 less than 5 ha on 89 TOTAL 3,006 100 islets. Surplus from Sources: McLean & Hosking (1991) and Seluka et al (1998). household vegetable cultivation is sold locally but there is no real commercial agriculture due to the small size of the land holdings that have been fragmented by the traditional land-tenure systems. In order to improve the poor soil that cannot support much vegetation, the National Waste Management Scheme runs a central composting plant to recycle organic matter. Villagers are encouraged to improve the soil organic content by buying compost at A$2.00 per kg and using it for growing crops and trees.
There are various types of land ownership: · Communal land (or common land) dating back to the times when the land was under the management of chiefs. · Village land, usually administered by the Island Council · Crown land, usually comprises foreshore and sea-bed land · Acquired land, i.e. land acquired by the government for specific purposes · Leased land · Private land, held by separate individuals or land groups The government can easily acquire land that may be required for installation of renewable energy systems, and for transmission and distribution lines.
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5.2.3 Water and Sanitation
The main water supply on Tuvalu is from rainwater with ground water coming second. Only 60 % of households have access to piped water and all water must be boiled before drinking. The limited water resources are being stressed by the rapid population growth especially in the urban centers where the water is most prone to pollution.
Rainwater is collected from roofs of buildings and stored in tanks. The water can get contaminated throughout this process because of dirty roof catchments and gutters, poor filters on tank inlets and poor maintenance of tanks. The storage system has been improved considerably under the United Nations Community Development Fund Water Supply Project when around 450 households got ferro-cement water tanks. Community storage tanks were also provided for use during drought periods.
Groundwater is very limited on Tuvalu since the islands are all coral atolls. Due to the high water table and porous nature of the soil, groundwater resources can easily get polluted by salt-water intrusion and effluents from septic tanks and sewage. Other causes of water pollution are manure of animals and leaching of solid wastes. Due to scarcity of land, solutions like pit latrines are not an option since they fill up and require new ones. There is an urgent need to tackle the problems of sanitation.
Solid wastes are not disposed in a systematic manner, being dumped in many places in pits and beach areas. To address this environmental problem, Tuvalu is in the process of putting together a waste management strategy and legislation that will regulate sewage disposal and housing. This waste management strategy has a strong emphasis on recycling and organic fractions. A central piggery has been constructed where Tuvalan's can rent out places for their pigs so that the manure can be treated centrally.
5.2.4 Present Energy situation
The main sources of energy at present are imported fossil fuels (diesel, petrol, kerosene, bottled LPG), while a small proportion comes from biomass (fuel wood from trees) and solar PV. Fossil fuels are used for electricity generation, transportation and cooking:
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· Petrol and diesel are used for motor vehicles, fishing boats and ships. · LPG and kerosene are used for cooking. · Diesel is used in diesel power plants for generating electricity.
5.2.4.1 Electricity Generation
Diesel power plants
In 2002, the total diesel generation capacity on the 8 big islands was 4,027 kVA, with 62% of this capacity catering to the main island of Funafuti as shown in Table 19. The demand for electricity is increasing, so generating capacity also needs to be increased by the government owned utility - Tuvalu Electricity Corporation (TEC).
Table 19 Electricity production statistics for islands of Tuvalu CAPACITY FUEL FUEL ENERGY ENERGY ISLAND of Diesel ConsumptionConsumption Consumption Consumption Power Station Jan-July 2002 12 months Jan-July 2002 12 months (kVA) kilo-liters kilo-liters kWh kWh Funafuti 2,487 708 1,214 2,178,841 3,735,156 Nanumaga 220 16 28 }} Nanumea 220 16 28 }} Niutao 220 30 51 }} Nui 220 19 33 }} 301,831 517425 Nukefetau 220 17 30 }} Nukulaelae 180 15 26 }} Vaitupu 260 44 75 }} TOTALS 4,027 866 1,485 2,480,672 4,252,581 Source: TEC (2002)
From data available for the first 7 months of 2002, it is estimated that the annual diesel fuel consumed by power plants on all 8 islands is 1.48 million liters for supplying 4.25 million kWh of electricity to consumers. The main island of Funafuti alone uses over 80% of the fuel. Fuel costs are around A$ 1.2 million per annum representing over 50% of the total cost of generation. Electricity tariffs on Funafuti are A$0.34/kWh and on the outer Islands A$0.30/kWh. The total revenues for 2002 amounted to only A$1.21 million and the Energy Department subsidises electricity production by paying TEC nearly 50% of the cost of operation i.e. around A$ 1.2 million every year.
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Solar Photovoltaics (SPV)
SPV is being used to produce small amounts of power for lighting, pumping and communications systems. Over 400 SPV systems have been installed in homes whose energy demand has been estimated as given in the Table 20. This program is run by the Solar Electric Co-operative Society Ltd., which was formed in 1984.
Table 20 Energy demand for a Photovoltaic home in Tuvalu Energy demand Wh / day A typical home 3 lamps @ 11W operating for 6 hours 198 system, used for powering lights and 1 radio @ 16 W operating for 4 hours 64 a radio, has SPV 1 night light @ 0.5 W operating for 10 hours 5 panels rated at 100 TOTAL 267 Wp which delivers Source: Lifuka, K, (2003). an average of 270 Wh/day considering an average daily solar irradiation of 5.1 kWh/m2. The 400 SPV home systems produce around 40,000 kWh/year, amounting to roughly 1% of the power produced from diesel power plants.
Other useful applications of SPV tried on the outer islands are for refrigeration of vaccines in clinics and medical centers, satellite stations and for communications systems with (CB) radio telephone. One SPV pumping system has also been installed, consisting of a float, direct-coupled pump with a brushless DC motor powered by a 1500 Wp SPV array. Eight more SPV pumping systems are planned.
5.2.4.2 Cooking and heating
Fuel wood is used widely for cooking by communities on the outer-islands as well as in the urban areas. Imported LPG and kerosene are also used for cooking, but they are expensive. The high cost of imported cooking fuels together with the increasing population, especially in the urban centers, has led to the over-exploitation of fuel wood. Consequently, the town council of the largest urban center of Funafuti has banned the cutting of trees for firewood,
Two solar water heaters have been installed. These systems produce around 100 liters per day of hot water and are working satisfactorily. The solar water heaters help reduce the consumption of firewood.
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5.2.5 Renewable energy resources
5.2.5.1 Solar Energy
Monthly average values of the global solar insolation on a horizontal surface is given in the Table 21. The annual average insolation is good at 5.14 kWh/m2/day.
Table 21 Solar, Wind and Weather data for Tuvalu Latitude 8.5°S 8.5°S 8.5°S 8.5°S 8.5°S Longitude 179°E 179°E 179.2°E 179.2°E 179.2°E Solar Insolation on Wind speed at 50 Average Average Sea horizontal surface meters above ground Rainfall Temperature Level Pressure kWh/m2/day m/s mm °C millibars Jan 5.06 4.79 404.7 28.1 1007.0 Feb 4.98 5.26 368.6 28.0 1007.4 Mar 5.19 4.61 330.8 28.1 1008.2 Apr 5.14 3.84 253.7 28.2 1008.7 May 4.75 3.80 235.4 28.2 1009.1 Jun 4.57 4.34 235.2 27.9 1009.5 Jul 4.58 5.07 263.4 27.6 1009.6 Aug 5.20 5.12 265.4 27.7 1009.8 Sep 5.85 4.70 231.0 27.9 1009.9 Oct 5.80 3.96 283.0 28.1 1009.6 Nov 5.52 3.69 277.7 28.2 1008.3 Dec 5.09 4.84 393.5 28.1 1007.2 Annual 5.14 4.50 3543.9 28.0 1008.7 Source: NASA (2000) and World Climate (2000)
5.2.5.2 Wind Energy
Tuvalu, lying between 5 to 11 degrees south of the equator, does not enjoy good wind speeds. Monthly average wind speeds are given in the Table 21. The annual average wind speed at 50 meters above ground level is only 4.5 m/s. Smaller wind turbines for islands will be installed at heights of around 25 to 30 meters above ground level, where the wind speeds will be even lower.
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5.2.5.3 Hydro power
Tuvalu consists of low lying coral atolls and does not have any hydro power potential at all.
5.2.5.4 Biomass
About 4% of the land area is covered by broadleaf woodlands and 17% by mangroves. However, the main biomass resource of Tuvalu consists of coconut palms that cover over 1,600 ha, roughly 54% of the total land area. Coconuts are collected from naturally occurring palms and programs for replanting coconut trees, which were running for a while, have now been stopped because of a lack of funds. Tuvalu has over 500,000 coconut palms with an average density of 254 palms/ha. The capital island of Funafuti with its populated centers has the lowest average at 151 palms/ha while Vaitupu, the agricultural center, has a maximum density of 351 palms/ha in. Each coconut palm produces an average of around 80 nuts /yr.
Table 22 Copra production in Tuvalu ISLAND YEAR 1999 YEAR 2000 The main commercial value of the Funafuti 1,937 232 coconuts is the dried flesh called Nanumaga 74,555 48,602 “copra”. The shell and coir from the Nanumea 27,983 47,948 Niutao 38,235 19,629 nuts and the leaves can all be Nui 2,388 3,217 burned for their energy. The copra is Nukefetau 22,760 10,933 pressed for the coconut oil leaving Nukulaelae 28,679 11,123 the oil cake that is used widely to Vaitupu 54,833 120,893 feed animals. The copra production TOTALS 251,369 262,576 (Source: Taape I. 2003.) All figures in kgs on the islands is given in Table 22.
5.2.5.5 Wave power
In the late 1980s and early 1990s, SOPAC undertook a study on the wave climate of seven Pacific island states (Vanuatu, Tuvalu, Fiji, Western Samoa, Western Kiribati, Tonga and the Cook Islands). The study was funded by NORAD and carried out by the Norwegian company OCEANOR. One of the aims of this study was to generate sufficient data for evaluating the wave energy potential of the region. Long term
______K. Raghavan, FREI Page 51 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” wave measurements at 6 locations were combined with region-wide satellite wave height measurements to give an overall picture of the spatial variability of average and extreme ocean wave heights on an annual and seasonal basis. The accuracy of global numerical wave model data for the region was validated by means of short- term directional wave measurements at three locations in offshore, undisturbed sites. The study concluded that the area studied has a good wave energy potential.
The main findings of the study were: · In the open ocean, average annual wave heights vary from a little under 2 meters near the equator to nearly 3 meters at 30o south latitude. Seasonality in wave heights is modest particularly in the low latitudes. · Nearer the coasts, wave energy is still reasonably high, but seasonality is somewhat stronger due to island sheltering and seasonal changes in the dominant wind direction. · Extreme wave conditions result from cyclones that occur infrequently at any given location. Cyclones are, however, most frequent south of 10o south latitude and in the west of the region. Close to the equator cyclones do not occur and as a result extreme wave conditions are significantly lower. · Wave period and direction statistics are only valid for the buoy measurement locations. The exposure of the measurement location affects the data strongly and significant variation may occur even over short distances. The best method to assess wave power potential at new sites is to use long-term wave data from global wave models and correct them for any systematic biases using either measured directional wave data or satellite measurements. The offshore wave conditions can then be extrapolated to the site of interest using local area wave modeling.
Wave power has not been considered for the islands in this Case Study because the technology is still in the early stages of development. There are no proven and reliable wave power devices available in the international market. Recent advances in research and development of wave power devices in Denmark, U.K., Japan and other countries are encouraging. However, technical and commercial viability of the technology has to be demonstrated so that it can be used on remote islands with confidence.
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5.2.6 The 100% RE solution
The islands of Tuvalu can easily meet all their energy needs from RES using a combination of the following:
· Energy efficiency measures · Coconut oil for diesel engines in power plants and vehicles · Biogas plants for converting animal and human wastes into cooking fuel and organic fertilizer free of pathogens. · Biomass gasifiers using coconut waste and woody biomass.
5.2.6.1 Energy efficiency
There is potential for increasing efficiency on the both the supply and demand-side in the power sector. Technical programs can assist the power utility to improve its efficiency by implementing supply side measures. The consumers can be educated about energy conservation techniques and how to use electricity efficiently.
There is scope for improving the efficiency of burning of fuel wood for cooking. This should partly address the problem of shortage of fuel wood and over-exploitation that is causing negative environmental impacts. Improved cooking stoves not only use less fuel but they also improve the air quality in the kitchen thereby creating a more healthy environment especially for the women and children. This is a low-cost appropriate technology than can easily be made locally under technical guidance.
5.2.6.2 Coconut oil
The potential for using coconut oil as a renewable energy fuel has hardly been tapped in Tuvalu. All plant oils can substitute diesel fuel after making minor modifications to diesel engines. This means that diesel power plants as well as diesel engines used for land and sea transportation can run on coconut oil. This is a simple, proven and reliable technology that can cut down imports of diesel fuel drastically. By substituting coconut oil for diesel oil, the Tuvalu government will actually save a lot of money because the copra production that is currently being sold in Fiji, is subsidized heavily by the government.
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Taking the following into consideration, we can estimate the total potential coconut oil production of Tuvalu: · Coconut palms are being grown on 1,600 hectares. · One hectare has 254 coconut palms, on an average. · Each coconut palm produces an average of 80 nuts/ year. · 6 coconuts will produce 1 kg of copra. · The average oil production from 1 kg copra is 0.4 liter of oil (a conservative estimate).
The total potential coconut oil production of Tuvalu equals: 1,600 * 254 * 80 * 0.4 / 6 = 2.1 million liters
To estimate how much coconut oil will be required per year by all the diesel power plants we assume the following: · The density of coconut oil is 0.9 kg/ liter. · Coconut oil has an energy content of 40 MJ/ kg. · A diesel generator runs at 30% efficiency. · 4.25 million kWh /yr of electricity are produced by all the diesel power plants.
The coconut oil required per year to generate the total electricity produced by all the diesel power plants on Tuvalu equals: 4250 * 3600 / (0.3 * 40 * 0.9) = 1.4 million liters
Out of a total annual oil production of 2.1 million liters only 1.4 million liters is required by the diesel power plants. So 0.7 million liters still remains for the transport sector. The most important point is that there will be no need to import diesel fuel for the power plants. Let us take a brief look at the financial implications by considering the following figures from 2002:
· Copra is purchased by the Co-operative at a price of A$1 per kg, · World market price for Copra is A$0.3 to 0.4 per kg, let us take A$ 0.35 per kg. · The government spends A$0.2 per kg to ship the copra to Fiji. · Diesel is imported at a price of A$ 0.91 per liter (US$ 0.55 per liter)
The government spends A$ 1.2 per kg copra but can get only a price of A$ 0.35 per kg in the international market, therefore subsidising A$ 0.85 per kg of copra sold in
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Fiji. At the same time the govt. is buying diesel at A$ 0.91 per liter. Just by using coconut oil instead of diesel, the government will save A$ 0.91 per liter diesel and the copra shipping costs. There will also develop a local industry to produce the coconut oil from copra that will provide employment opportunities.
5.2.6.3 Biogas
The production of biogas from animal wastes, especially pigs, has a lot of potential in Tuvalu. Biogas is a good, locally produced substitute for imported LPG and kerosene, and for the scarce local fuel wood that is causing environmental concern. In addition, the biogas digester is an excellent method for treating animal waste and converting it into a good organic fertilizer. This can help to solve the pollution problems caused by animal wastes.
Table 23 Number of Pigs
Island Number The biogas plant for tropical latitudes is a simple, low- of pigs cost, proven, reliable and appropriate technology suitable for local manufacture. The digester can be Nanumea 1574 made of stone masonry, ferro cement, steel or plastics. Nanumaga 998 They are very simple to operate and maintain and Niutao 912 people with no technical training or education can learn Nui 659 to use them quickly. They will provide the ideal solution for the cooking energy needs since most of the people Vaitupu 2448 in Tuvalu raise pigs. On an average, 4 to 6 pigs provide Nukufetau 644 enough excreta for a 2 cubic meter biogas plant that can Funafuti 2452 meet the cooking needs of one family of 5 or 6 persons. Nukulaelae 375 As shown in Table 23, the total number of pigs in Tuvalu is 10,202. Since the total number of households is Niulakita 142 1,568, the average number of pigs per household in TOTAL 10,202 Tuvalu works out to 6.5. Of course there will be Source: Lifuka, K, (2003) households with fewer number of pigs, but when people realize the value of the pig manure, they will start raising more pigs.
In the case of a central facility where people can keep their pigs, a bigger biogas plant can be installed. The gas can be piped to the houses nearby for cooking, or it can be used by an entrepreneur for a small industry.
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Biogas digestors are also an effective way of converting human excreta into an organic manure without fear of spreading decease, since most of the pathogens are killed in the digestor. Around 5% of the pathogens remain at the bottom of the digestor, but the slurry is taken out of the digestor from the top, so it is quite safe. There are hundreds of thousands of such biogas plants in China where they have been used for many years, The typical Chinese rural biogas plant directly takes in the human waste from the latrine, the pig waste from the.pig sty and also absorbs any vegetable waste from the kitchen. This could prove to be a good solution for the disposal of human waste on Tuvalu, with the added benefit of getting biogas for burning as well. In some countries there is a social stigma associated with using the slurry from human excreta for growing food crops, but it could easily be used as organic fertilizer for the coconut palms and trees.
5.2.6.4 Biomass Gasifiers
After the copra has been removed from the coconut shell the remaining biomass, consisting of the shell and the coir outside the shell, can be burnt in a biomass gasifier. The producer gas from the gasifier can be used in burners for heating or cooking, or it can substitute upto 85% of diesel fuel in a diesel engine. To reach 100% renewable fuel the remaining 15% diesel can be substituted with coconut oil.
Gasification of coconut biomass is a more expensive way to substitute diesel than simply using coconut oil because of the additional capital and running costs of the gasifier, whereas the oil just needs to be pressed from the copra. However, it can be an attractive option if the coconut oil is required for other uses such as transportation or if it can be sold profitably.
To estimate the quantity of coconut biomass available for gasification and the amount of electricity that can be generated from it, we can use the following information: · Coconut palms are being grown on 1,600 hectares. · One hectare has 254 coconut palms, on an average. · Each coconut palm produces an average of 80 nuts/ year. · Each coconut will give around 1.8 kg of biomass for burning · 1 kg of biomass produces around 0.5 kWh of electricity
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The total quantity of coconut biomass available equals: 1600 * 254 * 80 * 1.8 = 58,521,000 kgs
The quantity of electricity that can be generated equals: 58,521,000 * 0.5 = 29,260,000 kWh = 29.2 million kWh
This is several times the present annual energy consumption of around 5 million kWh.
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5.3 Fiji
5.3.1 Basic Data
Figure 3 Map of Fiji showing locations of Koro and Moala islands
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Table 24 Basic Data on Fiji islands Capital Suva Population 801,500 (1999 est.) Land Area 18,333 km2 Max. Height 1,324 m (Tomanivi) above Sea-level Geography Over 320 islands (105 inhabited); mostly volcanic in origin; largest islands are Viti Levu (10,390 km2 ) and Vanua Levu (5,538 km2 ) EEZ 1.26 million km2 Climate Tropical oceanic with tempering influences of the prevalent Southeast trade winds Rainfall Varies; windward sides of larger islands are extremely wet while leeward sides have considerably less rainfall; ranges from approximately 440 mm in the west and 1120 mm in the Southeast per annum Mean 28°C Temperature Economy Diverse with strong tourism sector, sugar, agriculture, garment and mining industry; exports include sugar, garments, gold, coconut products, tropical fruits, root crops, vegetables, tobacco, fish, and timber products GDP per Capita US$ 2 684 (1998 est.) Currency FJ$ Energy Sources Hydro, biomass, solar, wind, wave, geothermal Freshwater Groundwater, surface water Sources Natural Hazards Cyclone, storm surge, coastal flooding, river flooding, drought, earthquake, landslide, tsunami and volcanic eruption Mineral On-land – gold, silver, copper; Offshore – polymetallic Potential sulphides (gold, silver, copper, lead and zinc), hydrocarbons Languages English, Fijian, Hindi Government Independent state since 1970 Source: Sopac (2002b)
The Fiji archipelago, lying between 16 and 20 degrees south of the equator, comprises of 332 islands. It has a land area of 18,300 km2 . and an EEZ of 1.26 million km2 . The population in 1999 was over 800,000, nearly 94% of whom live on the two main islands of Viti Levu and Vanua Levu.
5.3.2 Present Energy at Situation
The main sources of power are imported petroleum products, hydro power and biomass. The Fiji Electricity Authority (FEA) is responsible for power generation on
______K. Raghavan, FREI Page 59 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” the main islands and nearly 67% of the population is connected to the main electricity supply grid. FEA operates both hydro-electric and diesel power plants on the larger islands. Several small and medium scale industries have their own power plants. The Fiji Sugar Corporation produces most of its own power requirements using bagasse for co-generation, the Fiji Industries Ltd uses imported coal to fire the kilns in its cement factory and the Emperor Mine has a 30-MW diesel power plant. The Public Works Department (PWD) is responsible for the small and medium scale diesel power plants on the remote islands.
The Department of Energy (DOE) aims to facilitate the development of a resource efficient, cost effective and environmentally sustainable energy sector in Fiji. In the power sector DOE facilitates private sector involvement in power projects and commercialization of RE technologies. DOE’s energy conservation program tries to educate consumers, both domestic and industrial, on the benefits of the rational use of energy and implementing energy efficiency measures. Awareness programs have been organized to promote energy-saving devices like compact fluorescent lamps, timers and efficient motors, and regular maintenance of high power equipment in industries. The Rural Electrification Unit (REU) of DOE is focused on providing power to un-electrified rural areas. The Office for Promotion of Renewable Energy Technologies (OPRET) OPRET carries out resource assessment studies and the planning and implementation of various RE technologies. Decentralized power generation based on RE is a major thrust area.
5.3.2.1 Fossil Fuels
Nearly 60% of the total electricity production (503 GWh in 1998) comes from diesel power plants. These include the large diesel grids operated by FEA, the small and medium diesel power plants operated by PWD on the remote islands, and the captive diesel plants of industries. Diesel and petrol are also used in the transportation sector by cars, trucks, buses and boats. Diesel imports are a heavy burden on the foreign exchange reserves. LPG is used for cooking mainly in the urban centers.
5.3.2.2 Hydro power
The 80 MW Monasavu hydroelectric power plant on Viti Levu supplies nearly 80% of the power requirements on the main island. There are several smaller micro and mini ______K. Raghavan, FREI Page 60 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” hydel projects on the two main islands and the outer islands. Realising the untapped potential of hydro power, DOE has carried out preliminary surveys for over 50 sites, many of which have been monitored and feasibility reports prepared.
5.3.2.3 Biomass
Biogas Biogas has been produced from both cow and pig manure. During 1996 and 1997, DOE installed a pilot 15.8 m3 biogas plant at a dairy farm in Tallevu. Two similar pilot demonstration projects using wastes from piggeries were also installed during this period at Nausori and Lautoka. Several more biogas plants have been completed since then. REU has also prepared a Biogas Plant Construction Manual.
Coconut Oil The Fiji Coconut Board and DOE undertook a feasibility study in 1999 for using coconut oil to generate power on the island of Taveuni. The South Pacific Commission (SPC) and CIRAD, a French NGO, also participated in this study. The implementation of this project was funded jointly by SPC and the Japanese Government.
5.3.2.4 Solar PV and Hybrid Systems
A 10-KV solar PV power plant provides power at Lautoka. SPV home lighting systems have also been used for providing domestic power for remote islands. The high cost of PV panels has prevented the large-scale use of this technology.
In 1998, a hybrid system using a combination of SPV, wind generators and diesel gensets was commissioned at Nabouwalu for supplying power to the government station and the village. The project was implemented under the Renewable Energy Development Program of DOE. The hybrid system consists of a 40 kWp SPV array, eight wind turbine generators, a battery bank, inverters and two 100 kVA diesel gensets for back-up. Nearly 100 consumers use the power including the govt. hospital, post office, agriculture and fisheries departments, PWD and its staff quarters, police station and staff quarters and shops. The cost of the project was shared by the Japanese Government , DOE and PWD.
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5.3.3 Renewable energy resources
5.3.3.1 Solar Energy
Monthly average values of the global solar insolation on a horizontal surface is given in the Table 25. The Fijian islands receive a good annual average solar insolation of 5.32 kWh/m2 /day, but the months of May, June and July receive only around 4 kWh/ m2/day.
Table 25 Solar, Wind and Weather data for Koro and Moala Latitude 18°S 18°S 18°S 18°S 18°S Longitude 178.5°E 178.5°E 178.5°E 178.5°E 178.5°E Solar Insolation Wind speed at Average Average on horizontal 50 meters Temp- Sea Level surface above ground Rainfall erature Pressure kWh// m2/day m/s mm °C millibars Jan 6.34 5.53 318.7 26.1 1007.7 Feb 5.97 5.35 271.0 26.3 1007.7
Mar 5.44 5.62 412.5 25.9 1008.9 Apr 4.78 6.68 400.7 25.1 1010.4 May 4.16 6.93 254.6 24.0 1012.5 Jun 3.96 6.82 141.4 23.2 1013.1 Jul 4.19 7.09 112.6 22.3 1014.0 Aug 4.83 6.85 139.7 22.4 1013.9 Sep 5.55 6.46 163.5 22.7 1014.1 Oct 6.15 6.84 210.8 24.0 1013.1 Nov 6.35 6.00 254.2 24.6 1011.0 Dec 6.15 5.99 264.0 25.1 1008.6 Annual 5.32 6.35 2947.1 24.3 1011.3 Source: NASA (2000) and World Climate (2000)
5.3.3.2 Wind Energy
Monthly average wind speed data is given in the Table 25. The annual average wind speed at 50 meters above ground level is 6.35 m/s. What is more interesting is that the wind speeds during May to August are highest at around 7 m/s. Since the solar radiation is lowest during these months, wind generators in combination with SPV in
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5.3.3.3 Hydro power
With a good rainfall and hilly terrain, Fiji has excellent hydro power resources on the two main islands and many of the outer islands. It is estimated that Fiji has an exploitable hydro power potential of 1 TWh /year of which only around 400 GWh are being produced, most of it coming from the 80 MW Monasavu hydel plant. There are around 8 to 10 mini and micro hydel schemes on the other islands.
Until 1994, a total of 60 potential hydro power sites had been surveyed by a number consultants hired by DOE. This included 36 sites on Viti Levu, 20 sites on Vanua Levu and 4 on the outer islands. In November 1994 the first “Report on Assessment of Mini / Micro Hydro Sites in Fiji” was prepared for DOE by the Japanese Overseas Co-operation Volunteers (JOCV) containing preliminary survey results for 34 more potential sites (Katsutoshi, 1994). The JOCV volunteer followed a very sound methodology. He used 1:50,000 topographic maps to identify potential sites and measure their catchment areas. The hydrology was analysed based on nearby rainfall data and gauging stations on rivers. The population and number of households in the villages was considered and whether they had already shown interest by making a request to DOE for electricity. For the short-listed hydel schemes, the stream flow and available head were measured. The sites were then ranked based on estimated construction costs. Since then JOCV volunteers have continued the work and in 2002 a second report was published t with preliminary survey results for another 57 sites (Nakatsugawa, 2002)
5.3.3.4 Biomass
Biomass resources of Fiji include · Coconut shells and husks, · Timber industry - sawdust, waste timber, logging residues · Sugar cane tops, bagasse · Agricultural residues – rice hulls, rice and maize straws · Animal wastes – pigs, cows, chicken, other animals
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· Solid wastes – municipal garbage dumps
5.3.3.5 Ocean energy
Ocean Thermal Energy Conversion (OTEC)
OTEC in the Fijian islands has been studied by both the Japanese and the British. In 1982 the UK Department of Industry together with some private companies began work on the development of a floating 10 MW closed-cycle OTEC demonstration plant for a site on the island of Vanua Levu. The conceptual design for a land based, integrated Ocean Thermal Energy Conversion / Deep Ocean Water Applications (OTEC/DOWA) plant was carried out by a group of Japanese industries. However, these two ideas were not implemented. In this connection, it is interesting to note that, in 1981, the Tokyo Electric Power Company built a 100 kW shore-based, closed-cycle OTEC pilot plant on the island of Nauru, which gave a net output of 31.5 kWe during continuous operating tests (WEC, 2000). . Wave power
Wave power potential for Fiji is the same as for Tuvalu – please refer section 6.2.5.5.
5.3.4 The 100% RE solution
OPRET is interested in making two of the outer islands of Fiji into “100% Renewable Energy Islands”:
· Koro island in the Lomaiviti group · Moala island in the Lau group
5.3.4.1 Koro island
Koro is a young volcanic island consisting mostly of steep land covered with a lot of vegetation. It has a land area of 110 km2 and a population of around 3,000 people living in 14 villages. Nasau, the largest village on the island, is the administrative center where the government offices are located. The government center includes
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The island has one Health Center at Nasau and two nursing stations at Nabasovi and Nacamaki. There are seven primary schools and one high school. The high school, which is the only boarding school on the island, offers education upto Form 6 level. There is also a Circuit School in Namacu.
The villagers are subsistence farmers. The people earn their living through the sale of rootcrops, seafood, coconuts, kava, mats and other handicrafts. Most villagers keep animals only for domestic purposes and there is one Cattle Farm in Vatulele. However, there is potential on the island for fishing, cattle farming, and handicrafts that still needs to be tapped.
Koro has one tourist resort at Dere Bay in Nabasovi that uses solar photovoltaic power. Currently there are 30 vehicles on the island but there is no garage for repairing and maintaining them.
Basic data for all 14 villages on Koro is given in the Table 26.
Table 26 Basic data on Koro island # Village Diesel Hydro School School Health Govt. Resort Scheme Poten- with Centre/ Centre tial diesel Nursing scheme Stations 1 Mudu 3 3 5 5 5 5 5 2 Nakodu 3 5 3 3 5 5 5 3 Namacu 3 3 3 5 5 5 5 4 Sinuvaca 5 5 3 3 5 5 5 5 Naqaidamu 3 3 5 5 5 5 5 6 Nasau 3 3 3 3 3 3 5 7 Tuatua 3 3 5 5 5 5 5 8 Nacamaki 3 5 3 3 3 5 5 9 Nabasovi 3 5 3 3 3 5 3 10 Tavua 5 5 5 5 5 5 5 11 Navaga 3 3 5 5 5 5 5 12 Kade 3 5 3 5 5 5 5 13 Nabuna 3 3 3 5 5 5 5 14 Vatulele 5 5 5 5 5 5 5 3 yes 5 no Source: Sauturaga, M., 2003
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5.3.4.2 Moala island
Moala is a rugged, mountainous, high island with a number of streams and rivulets and good vegetation. The island has an area of 62 km2 with a population of around 1,600 living in 8 villages. Naroi is the administrative center where government offices are located. The government center includes the Ministry of Primary Industries, Provincial Office, Public Works Department, Post Fiji, and Police Station. Naroi also has an airfield that caters for weekly flights.
Moala has seven primary schools and one junior secondary school. The secondary school, which is the only boarding school on the island, provides education upto Form 4 level. There is one Health Centre in Naroi, and two nursing stations in Cakova and Nasoki.
The villagers are subsistence farmers. The people earn their living through the sale of rootcrops, seafood, and copra exported to Suva. The villagers keep animals only for domestic purposes. There is, however, potential on the island for fishing, eco- tourism and pine plantations.
The quality of life on Moala is comparatively lower than on the other outer islands of Fiji. The people generally prefer to travel between villages, to the hospital and other facilities at Naroi by boats with outboard motors, rather than using the poor roads.
Basic data for all 8 villages on Moala is given in the Table 27.
Table 27 Basic data for Moala island # Village Diesel SPV Hydro School School Health Govt. Air- Sch- Poten- with elect- Centre/ Centre field eme tial rification Nursing scheme Stations 1 Naroi 3 3 5 3 3 3 3 3 2 Vunuku 3 5 5 3 3 5 5 5 3 Keteira 3 5 5 3 3 5 5 5 4 Nasoki 5 5 5 3 5 3 5 5 5 Cakova 5 5 5 3 5 3 5 5 6 Nuku 5 5 5 3 5 5 5 5 7 Vadra 5 5 5 3 5 5 5 5 8 Maloku 5 5 5 3 5 5 5 5 3 yes 5 no Source: Sauturaga, M., 2003
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5.3.4.3 Energy needs
Electricity 11 out of the 14 villages in Koro and 3 out of the 8 villages in Moala are already electrified with diesel generating sets. The electricity is used mainly for domestic appliances, and in the schools, government offices, hospitals and nursing homes. If more power is made available from RE, especially in the daytime, the other electrical loads that can be expected are: · Ice making for preserving the fish. · Appliances – refrigerators, washing machines. · Schools - computers, satellite dish, internet connection. · Machines for weaving, handicrafts, wood carvings. · Workshops for boat and automobile repair. · Oil presses for making coconut oil.
Cooking Firewood is the main fuel used for cooking. This is done quite inefficiently and also causes some air pollution in the kitchens affecting the health of the women and small children.
5.3.4.4 RE Technologies
It is quite feasible to stop using fossil fuels completely on the islands of Koro and Moala. Using cheaper and cleaner power from the following RE sources, the quality of life on the two islands can be improved considerably:
Micro hydel schemes The potential for micro-hydel at 7 sites on Koro island is already established. A detailed survey and feasibility study will show the electricity generation capacities at these sites. It is possible that some of the sites can serve two or more villages. The topography and rainfall of Moala indicate a strong possibility of finding potential micro-hydel sites on this island also. Since hydro power is the cheapest and best of the RE technologies, it should be the first choice for electrifying the villages..
To use the power from micro-hydels in the daytime, business enterprises, and small and cottage industries that can process local agricultural produce and seafood
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Health and educational facilities will also improve with a reliable source of power for 24 hours. Hospitals can not only operate equipment more efficiently but also offer better living conditions to the doctors and other staff thereby attracting more talented workers to come and live on the island.
Audio-visual aids and an improved teaching environment can make a tremendous improvement in the education imparted in schools. Vocational training schools teaching workshop skills and training electricians and craftsmen can expand their syllabus and offer more practical training. Computers and internet connections using satellite dishes can allow school students to keep up with modern advances and prepare them for further studies in universities on the main islands.
Biogas Since most people keep domestic animals, biogas for cooking and farmyard manure has good potential. The Cattle Farm on Koro can have a larger biogas plant, the energy from which can be used for milk or meat processing.
Coconut oil Instead of selling the copra grown on the islands, coconut oil can be pressed and used as a substitute for diesel for generating electricity. This will provide power to the villages where there is no potential for micro-hydel power supply. Coconut oil can also be used to substitute diesel used in vehicles and boats
Biomass Gasifiers Another option for substituting diesel is by means of gasifiers using wood or coconut waste (shells and husk). This can also provide heating requirements for small industries such as milk or fish processing.
Improved cook stoves Improved cook stoves are an excellent way to use fuel wood more efficiently and also improve the air quality in the kitchen. ______K. Raghavan, FREI Page 68 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga”
5.4 Tonga
5.4.1 Basic Data
Figure 4 Map of Tonga showing location of Niuatoputapu island
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Table 28 Basic Data on Tonga Capital Nuku’alofa Population 100 000 (1999 est.) Land Area 649 km2 Max. Height above Sea-level 1 030 m (Extinct volcano, Kao) Geography Consists of about 150 islands (36 inhabited); archipelago of coralline and volcanic islands; 3 main island groups comprising the southern Tongatapu group, the central Ha’apai group and the northern Va’vau group EEZ 700 000 km2 Climate Tropical; modified by trade winds; wetter months (December to March) and cooler months (June to September Rainfall Varies from 1 500 – 2 500 mm per annum Mean Temperature 27°C Economy Dependent on aid, remittances, agriculture, forestry, fishing and tourism; exports include squash, banana, copra, vanilla, vegetables and fish products GDP per Capita US$ 1 868 (1998 est.) Currency Pa’anga Energy Sources Biomass, solar, wind and wave Freshwater Sources Groundwater, rainwater, surface water Natural Hazards Cyclone, storm surge, coastal flooding, drought, earthquake, tsunami, volcanic, eruption, river flooding and landslide Mineral Potential On-land – unknown; Offshore – polymetallic sulphides (gold, silver, copper, lead and zinc), hydrocarbons Languages Tongan and English Government Independent kingdom and member of Commonwealth Source: Sopac (2002c)
The Kingdom of Tonga is an archipelago of about 150 coralline and volcanic islands of which 36 are inhabited. The islands lie between 15 and 22 degrees south of the equator. The total land area is around 649 km2 with a maximum height of 1 030 m above sea-level. The Exclusive Economic Zone (EEZ) extends over 700 000 km2. There are three main groups of islands - Tongatapu group in the south, Ha’apai group in the center and the Vava’u group in the north. In the far north is the small Niuas group of islands, one of which called Niiuatoputapu has been selected for this
______K. Raghavan, FREI Page 70 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” case study. Most of the population of nearly 100 000 people (1999) live on the five main islands - Tongatapu, Vavau, Haapai, Eua and Niuas.
The main sectors of the economy are agriculture, forestry, fishing and tourism, but development aid and remittances from Tongans working abroad play a major role. Similar to a lot of SIDS, Tonga faces sustainable development and environmental issues such as sea-level rise, coastal erosion, water quality, water availability and sanitation, environmental degradation and pollution.
Over 80% of the population depends on groundwater while the rest use rainwater. In areas where the groundwater has turned brackish it is used for washing and rainwater is used for drinking. Coconut water has proved invaluable on some of the outer islands during periods of drought. Groundwater resources are being contaminated by human and animal waste, and saltwater intrusion. The Tonga Water Board operates a water treatment plant for the capital, Nuku’alofa.
5.4.2 Present Energy Situation
Nearly 40% of the energy required for domestic, commercial and industrial needs comes from imported petroleum products, mainly diesel and LPG. On the 5 main islands (Tongatapu, Vavau, Haapai, Eua and Niuas) the Tonga Electric Power Board operates diesel power plants to produce electricity. Consumers pay T$ 0.37 / kWh for the electricity on the main islands.
In 2002, diesel power plants were installed on four remote islands of the Haapai group with funding by Australia. The power plants are running well but people have the capacity to pay only for lights and fans, so no other development has taken place as a result of the availability of power. The electricity tariffs on the remote islands are much higher at T$ 0.75 / kWh. Kerosene is also used for lighting on the remote islands. It is subsidized by the govt. and sold at a price price of T$0.96 / litre.
The Tonga Solar Rural Electrification Program (TSREP) has been promoting the use of solar photovoltaics for providing electricity to people in the outer islands. Consequently, all the remote outer islands except three are served by SPV home lighting systems. Two of these three un-electrified islands, Niuafoou and Tafahi, will receive SPV home lighting systems in the near future, under funding from New
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Zealand. That will leave only one island without electricity – Niuatoputapu which has therefore been selected for this case study.
Biomass, mainly firewood and coconut husks, is widely used for cooking. Over- exploitation is already causing scarcity on the heavily populated islands. Imported LPG is also used for cooking in the urban centers but it is the more expensive option. The cost of LPG is over T$2/kg on the main island
The transportation sector depends totally on imported fossil fuels. Trucks, cars and ships run on diesel, while cars and boats use petrol. The price of diesel is T$1.40/ litre on remote islands and T$1.29/litre on main island, and the price of petrol is T$1.45 on remote islands and T$1.25 /litre on main island.
Solar Water Heaters are manufactured by one company in Tonga and are used on the main island. Since the government does not provide any subsidy on solar water heaters, people on the remote islands cannot afford these systems.
5.4.3 Niuatoputapu
The kingdom of Tonga has only three un-electrified islands. Two of these islands, Niuafoou and Tafahi, will be electrified with SPV home lighting systems in the near future leaving only one island in Tonga that still needs electricity. This last un- electrified island called Niuatoputapu has been selected for this Case Study because the Energy Department of the Government of Tonga is interested in making it into a model 100% RE Island.
Niuatoputapu has a land area of 18.81 sq.km. The 2000 Census showed that the island has a population of 1,076 persons living in 5 villages. There are totally 221 households. Each village has a primary school and a church. There is one high school for the whole island and also one hospital. The Government representative is the highest post on island but even the government staff quarters do not have electricity. Community ties are very strong on the island and once every month there is a community meeting for adults called Fono.
The main occupations are: · Agriculture - taro, yam, water melons, vanilla, cava.
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· Fishing - deep sea and shallow water fish is sold and eaten. The selling price of fish on the island is only T$5/kg. If ice is available then the fish can be frozen and sold on the main island for T$20 /kg. · Handicrafts - weaving, tapa clothing for decoration, funerals, weddings, exports & sale to tourists. · Remittances from islanders working elsewhere are an important source of income.
5.4.4 Renewable energy sources
5.4.4.1 Solar Energy
Monthly average values of the global solar insolation on a horizontal surface are given in the Table 29. Tonga gets a fairly good annual average insolation of 5.3 kWh/m2/day, though the seasonal variation is quite high with a maximum of 6.69 kWh/m2/day in January and a minimum of 3.67 kWh/m2/day in June.
Table 29 Solar, Wind and Weather data for Tonga Latit- ude 21°S 21°S 21.1°S 21.1°S 21.1°S Long- itude 175°W 175°W 175.2°W 175.2°W 175.2°W Solar Insolation Wind speed at 50 Average Sea on horizontal meters above Average Level surface ground Rainfall Temperature Pressure kWh/m2/day m/s mm °C millibars Jan 6.69 6.23 194.0 25.6 1009.6 Feb 6.28 6.01 218.1 26.0 1009.6
Mar 5.60 6.12 225.3 25.8 1009.7 Apr 4.68 7.44 158.3 24.9 1011.6 May 3.91 7.03 114.7 23.1 1013.5 Jun 3.67 6.94 92.4 22.4 1014.5 Jul 3.84 7.01 100.5 21.3 1015.1 Aug 4.51 6.99 117.0 21.2 1015.1 Sep 5.25 6.19 121.8 21.7 1015.6 Oct 6.16 6.88 132.5 22.4 1014.8 Nov 6.58 6.78 121.7 23.5 1012.2 Dec 6.40 7.02 140.4 24.7 1010.3 Annual 5.30 6.72 1738.4 23.5 1012.6 Source: NASA (2000) and World Climate (2000)
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5.4.4.2 Wind energy
Wind speed data is given in Table 29. The annual average wind speed at 50 meters above ground level is 6.7 m/s. Data from the airport met station indicates an annual average of 5.26 m/s probably at a lower height of 10 – 20 meters above ground level. This wind speed is good enough for small wind-SPV hybrid systems since the monthly data shows that the solar and wind resources are complimentary – the low solar radiation months have the highest wind speeds and vice versa as shown in Table 29.
5.4.4.3 Hydro power
Niuatoputapu has no hydro power resources.
5.4.4.4 Biomass
The main biomass resources on Niuatoputapu are · Coconut trees - around 200 tons /year of copra are produced on the island. The coconuts are used for cooking, drinking and to feed animals. Copra is also exported to overseas markets. · Woody biomass, grass – around 100 tons /year used as firewood and fodder. · Animal wastes – almost every family keeps pigs
5.4.4.5 Wave energy
The potential for harnessing wave power in Tonga is the same as for Tuvalu – please refer section 6.2.5.5.
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5.4.5 The 100% RE solution
5.4.5.1 Energy needs
Looking at the way loads have developed on other islands, it is possible to predict that, if power is made available on Niuatoputapu, the loads will be: · Ice making for preserving the fish. · Appliances – lights, fans, radio, TV, refrigerators, washing machines. · Schools - computers, satellite dish, internet connection. · Hot water from solar water heaters. · Machines for weaving, handicrafts, wood carvings. · Workshop for boat repair.
5.4.5.2 RE Technologies
All the energy requirements of the people of Niuatoputapu can be supplied by using the following renewable energy technologies. Details of the suitability of these technologies are the same as described in the Section 5.2.3 on Tuvalu.
· Coconut oil for diesel engines in power plants and vehicles · Biogas plants for converting animal and human wastes into cooking fuel and organic fertilizer. · Biomass gasifiers using coconut waste to run diesel engines in power plant. · Improved cook stoves to use firewood more efficiently.
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5.5 Road Map
The process of reaching 100% RES on islands consists of the following main steps:
1. Pre-feasibility Study to determine the existence of the major parameters that will indicate if it is worthwhile to invest resources to study the islands in more detail. These include the interest of the local government and the existence of RES so that the possibility of making the island into a 100% RE Island is established. This Case Study is essentially a Pre-feasibility Study for 100% RE supply for eleven islands in Tuvalu, Fiji and Tonga.
2. Detailed Feasibility Study will produce a document that can be used to secure funding for the implementation of project. This report will contain: a) Complete details including a time-frame for implementing the “100% RE Islands” plan. b) Technical specification and costs of all RE equipment to be used. c) Layout of the RE plants and the transmission and distribution systems. d) Logistics of transportation and installation of equipment. e) Operation and maintenance procedures f) Possibilities for technology transfer and local manufacture of RE equipment. g) Possibilities for small and cottage industries to utilize the RE power. h) Roles and responsibilities of all actors - the local communities and institutions, government agencies, NGOs. manufacturers and suppliers of equipment, etc. i) Possible funding mechanisms for implementation of the plan. j) Capacity building and Training requirements for · installation, operation and maintenance of the RE systems · local manufacture of equipment · entrepreneurs to start small businesses and industries quickly.
3. Implementation of 100% RE Plan during which the proposed energy efficiency measures and RE systems will be installed in a phased manner. This can be done over a period of 5 to 10 years, maybe even less than 5 years for the smaller islands. A more detailed time frame for the
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implementation is very specific to each island and will be prepared during the Feasibility Study.
After these eleven islands have become “100% RE Islands” we have not come to the end of the road. This is not a one-off project and the first 100% RE island is not an end in itself but only the beginning of the work. During the process of implementation of this project the replicating effect that must arise as a result should always be kept in mind. The successful implementation of several “100% Renewable Energy Islands” on Tuvalu, Fiji and Tonga is only the beginning of the long road leading to a sustainable energy supply on all SIDS. Energy planners on all the SIDS must try to make at least one of their islands into a “100% Renewable Energy Island” and simultaneously start planning how the entire country can live without fossil fuels. For the larger SIDS it may be a very difficult exercise and it could take a very long time to reach 100% RE status, but plans still need to be made since that is the only long term solution to the energy needs of our planet.
5.6 Obstacles & Remedies
Obstacle #1 Past experience indicates that the fossil fuel business has strong commercial interests and certainly would not like to see “fossil fuel free” islands or regions. Vested interests include the production and distribution of fossil fuels, as well as the transportation of these fuels to the islands. Owners of ships that carried fresh water to the Greek islands resisted attempts to produce water locally using RE powered desalination plants.
Remedy The strategy to overcome this obstacle can consist of two parts. · Firstly a strong political commitment is necessary. National interests must override petty commercial concerns of a few individuals. The government has to firmly believe in sustainable energy supply and, if necessary, introduce regulations and legislation that will confirm this belief and take the country forward on the road to a “fossil fuel free” economy and life style. · Secondly, the people who gain financially from sale of fossil fuels can be given an alternate way to make money. They can be involved in the process of introducing RE technologies on the islands. Many of them will be happy to make their living
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from a clean technology that prevents damage to the environment caused by usage of fossil fuels and its destructive effects on islands like sea-level rise.
Obstacle #2 Many development projects on SIDS have met with resistance from local communities and groups who cannot see what they are gaining as a result of the project but only what they are losing. The politicians and government departments together with businessmen decide on a course of action from which a few people gain financially. What makes it worse is that sometimes the people who make the most money are not even from the island.
Remedy Community involvement is absolutely essential to ensure a harmonious and successful development of the “100% Renewable Energy Islands”. Right from the start, the people of the island should feel a part of the process that will take them towards a sustainable energy supply. They must have sufficient opportunity to express all their concerns and their energy and development needs and priorities. Awareness campaigns should sensitize them to the overall benefits in moving towards a energy supply based on 100% RE. The development benefits of the energy should be very clear and fulfill the expectations of the people. Every time there is an important decision to be made concerning the project that will affect the people, the community should be consulted and their concerns taken into account. The islanders should be made to feel that it is “their own” project and not something just handed down from the top.
Obstacle #3 The RE technologies for the islands have been chosen keeping in mind the remoteness of the islands. Technologies that are still under research and development or in the early stages of commercialisation, such as wave power, have been avoided. Only technologies that have a proven reliability for many years and have already seen successful operation in large numbers will be used so that the chances of success are very high. However, experience with RE systems in remote locations on islands and elsewhere have shown that a lack of proper operation and maintenance has been the cause of many failed projects.
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Remedy Local companies and staff must be given rigorous training in operation and maintenance of the power generation and the transmission and distribution equipment. This should include both theoretical and practical training. They should be involved in all stages of the installation so that they are familiar with the system
Two levels of maintenance teams can be organized: (a) Operators of each of the systems can take care of minor repairs and routine maintenance, while (b) Central maintenance teams can visit the sites periodically and carry out major maintenance tasks and repairs. Sufficient spare parts for both should be budgeted for in the project and stocked at convenient locations. In addition there should be a contingency budget to take care of unforeseen major damage to equipment caused by extreme events.
5.7 Evaluation Methodology
To evaluate the process of reaching the “100% RE Island” the energy usage and the sources for each of the energy sectors will be monitored. The main sectors for energy consumption are: 1. Electricity 2. Heating 3. Cooking 4. Transport 5. Water production 6. Industries
Since the geographical boundaries of the islands are clearly demarcated it will be easy to keep a track of how much of each of the fossil fuels are imported - diesel oil, petrol, kerosene, coal and natural gas. Data on energy from RES used on the island will be monitored or estimated depending on the resource and the application. a) Coconut oil production figures from the oil presses will be recorded. b) The amount of coconut oil used by the diesel power plants will be obtained from the operators’ log books. c) Amount of coconut oil used by the transport sector will be obtained from the filling stations.
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Data for fossil fuel usage will be combined with power production data (electrical & thermal) from the renewable energy technologies to determine the percentage of RE in the energy mix at all stages of the project.
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6 CONCLUSIONS
6.1 Summary
Sustainable energy solution for islands on SIDS essentially means an energy supply from RES. By looking at the progress made by SIDS over the last 10 years, it is evident that much more needs to be done quickly to reduce fossil fuel imports by using energy more efficiently and increasing the share of RES in the energy supply. Having a few “100% Renewable Energy Islands” on SIDS will show that it is possible to live without fossil fuels and encourage other islands to plan and move towards a totally sustainable energy supply based on RES.
This Case Study has therefore looked at the following: 1. Examples of islands that are planning to become “100% Renewable Energy Islands” and have started moving towards this goal. 2. The main elements of a totally sustainable energy solution for islands based on energy efficiency and renewable energy technologies. 3. A strategy that can make several islands on SIDS into “100% Renewable Energy Islands”.
6.1.1 Examples of RE Islands
The European Union (EU) has one of the most focussed programs to promote large- scale implementation of renewable energy technologies on their islands. There has also been a lot of encouragement and financial support for islands that want to have 100% RES supply both from the EU and from individual European governments. A number of islands in Europe have made realistic plans to achieve 100% RES supply over a period of 10 to 20 years and many of these islands have started moving definitively towards this goal.
The most remarkable example is the island of Samsoe in Denmark that made a 10- year plan in 1997 to become a “100% RE Island” using mainly solar, wind and biomass energies. After 5 years, the island produces from RE nearly all the energy that is consumed. 57% of its heating energy needs, and over 100% of energy used for electricity and transport come from RES. Fossil fuels used in the transport sector
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6.1.2 Elements of a “100% RE Island”
The main elements that will make an island into a “100% RE Island” can be grouped into two categories: · Energy efficiency measures that will reduce energy consumption as far as possible. · Renewable energy technologies that will eliminate fossil fuel consumption.
6.1.2.1 Energy Efficiency
It is possible to reduce energy consumption by around 50% through the implementation of measures for energy efficiency and the rational use of energy and still meet all the energy needs of an island society. The main sectors in which energy savings are possible on islands and measures for rational use of energy and energy efficiency are summarized in the Table 30. Almost 30% savings are possible in energy used for water, heat & AC, 60% in energy for transport and 40% in electricity consumed.
Table 30 Energy Efficiency measures # Energy Sector Efficiency measures 1 Residential · Efficient lamps & refrigerators · Insulation & Glazing · Bio-climatic concepts · Zone heating & cooling 2 Transport · Fuel efficient vehicles · Urban planning · Good public transport · Car pooling 3 Industry · Efficient motors, boilers, furnaces · Waste heat recovery 4 Tourism · Eco tourism 5 Power distribution · Decentralised generation · Demand side management 6 Water production · Integral water management · Reduce, reuse & recycle
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6.1.2.2 RE Technologies for Islands
Table 31 RE Technologies and Usage # RES Technology Usage The renewable energy 1 Hydro Micro-hydel Electricity sources for islands are 2 Biomass Gasifiers Heat, Electricity Biogas Heat, Electricity, listed in Table 31 together Cooking with the major technologies Biofuels Electricity, that can be used to harness Transportation 3 Solar Thermal Water heating, them. While selecting collectors Drying, Cooking appropriate RE Photovoltaics Electricity technologies for meeting 4 Wind Generators Electricity Windpumps Pumping water the energy demands, 5 Ocean OTEC Electricity, Water several considerations are Wave power Electricity important, as indicated by Tidal power Electricity past experiences in developing countries, especially at remote sites: · Technical maturity · Reliability is more important than efficiency · Possibility of local manufacture of equipment · Suitability to local conditions · Ease of installation, operation & maintenance · Costs
6.1.3 “100% RE Islands” on SIDS
Eleven islands on three SIDS in the south Pacific have been selected for this Case Study (eight islands in Tuvalu, two in Fiji and one in Tonga). The selection criteria included: · The government of the island state should be strongly interested in making one or more of their islands into “100% RE Islands”. · The islands should be small with a population of around 1000 or less so that funds required for implementation will be modest. · There should be no power supply at present or only a diesel power plant. · There should be evidence of sufficient renewable energy sources, preferably hydro power or biomass.
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· There should be possibilities for productive, income generating activities.
The energy requirements on these islands are: · Appliances – lights, fans, radio, TV, refrigerators, washing machines, etc. · Schools - computers, satellite dish, internet connection. · Hospitals – medical equipment, air conditioning, refrigeration, sterilizing, etc. · Telecommunications. · Cooking & hot water. · Machines for weaving, handicrafts, wood carvings. · Workshop for boat and automobile repair. · Ice making for preserving the fish. · Oil presses for making coconut oil.
Data collected about the RE resources on the eleven islands indicates that they can stop using fossil fuels and meet all their energy needs from RE technologies. Table 32 gives details of the RE technologies that can be used in the three island states.
Table 32 The "100% RE Islands" solution ISLAND NO. of # RE RESOURCE USAGE STATE ISLANDS A Coconut oil · Electricity · Transportation B Biogas from animal and human · Cooking gas TUVALU 8 waste · Fertiliser C Producer gas from gasifiers using · Electricity coconut waste and woody biomass · Heat A Micro-hydels · Electricity B Biogas from animal and human · Cooking gas waste · Fertiliser FIJI 2 C Coconut oil · Electricity · Transportation D Producer gas from gasifiers using · Electricity coconut waste and woody biomass · Heat A Coconut oil · Electricity · Transportation B Biogas from animal and human · Cooking gas TONGA 1 waste · Fertiliser C Producer gas from gasifiers using · Electricity coconut waste and woody biomass · Heat
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6.2 Additional Studies
For implementing the “100% Renewable Energy Islands” plan on the eleven selected islands it is necessary to carry out feasibility studies. This will produce a document that can be used to obtain funding for the implementation of plan. The Feasibility Studies should contain the following:
a) Complete details including a time-frame for implementing the “100% RE Islands” plan. b) Technical specification and costs of all RE equipment to be used. c) Layout of the RE plants and the transmission and distribution systems. d) Logistics of transportation and installation of equipment. e) Operation and maintenance procedures f) Possibilities for technology transfer and local manufacture of RE equipment. g) Possibilities for small and cottage industries to utilize the RE power. h) Roles and responsibilities of all actors - the local communities and institutions, government agencies, NGOs. manufacturers and suppliers of equipment, etc. i) Possible funding mechanisms for implementation of the plan. j) Capacity building and Training requirements for · installation, operation and maintenance of the RE systems · local manufacture of equipment · entrepreneurs to start small businesses and industries quickly
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7 REFERENCES
Altener. (2002). Cluster AL/2000/0013 - 100% Renewable Islands. Islenet.
Anon. (1994). Programme of Action for the Sustainable Development of Small Island Developing States. Report of the Global Conference on the Sustainable Development of Small Island Developing States, Bridgetown, Barbados, 25 April-6 May 1994.
Anon. (2000). Energy and Sustainable Development. Pacific Regional Submission to the 9th Session of the Commission on Sustainable Development (CSD9), December 2000.
Anon. (2002). The Agreed Record. Pacific Islands Regional Energy Meeting, Rarotonga, Cook Islands, 15–19 July 2002.
AOSIS. (2001). Report of the 3rd AOSIS Workshop on Climate Change, Energy and Preparations for the 9th Session of the Commission on Sustainable Development. Nicosia, Cyprus, 15 - 19 January, 2001.
CROP. (2002). Pacific Energy Policy. Committee of Regional Organisations of the Pacific - Energy Working Group.
DG TREN (2000), Directorate General for Transport and Energy, European Commission.
Env. Sci. 101, Nov. 15, 2002, Lecture 20 - Fossil Fuels, http://epswww.unm.edu/facstaff/zsharp/103/lecture%2020,%20fossil%20fuels.pdf
European Commission (EC). (1998). Energy For The Future: Renewable Sources Of Energy (Community Strategy And Action Plan) - Campaign For Take-Off. Commission Services Paper.
European Commission (EC). (1999). Energy as a Tool for Sustainable Development for African, Caribbean and Pacific countries. European Commission and UNDP.
Forum for Energy and Development (FED). (1999). “Proceedings of the Global Conference on Renewable Energy Islands”. Forum for Energy and Development.
Govt. of Fiji. (1994). Rural Electrification Policy (1993). Government of Fiji.
Govt. of Fiji. (2001). Fiji Corporate Plan (2001). Government of Fiji.
Insula. (2001). Islands 2010 - Renewable Energy Sources for Island Sustainable Development. INSULA and ITER.
Katsutoshi, K. (1994). Report on Assessment of Mini / Micro Hydro Sites in Fiji No.1. Department of Energy, Govt. of Fiji.
Lifuka, K. (2003). Dept of Energy, Govt of Tuvalu. Email communication, August 2003.
McLean R F., Hosking P L., (1991). Tuvalu Land Resources Survey- Country Report (FAO) AG; TUV/80/011
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Nakatsugawa, H. (2002). Report on Assessment of Mini / Micro Hydro Sites in Fiji No.2. Department of Energy, Govt. of Fiji.
National Aeronautics and Space Administration (NASA). (2000). Monthly Averaged Regional Data Sets. http://eosweb.larc.nasa.gov/cgi-bin/sse/
Prasad,R., Kumar,M. and Narayan,C. (1999). Coconut Oil as Substitute for Fossil Fuels: A sustainable resource for the South Pacific; South Pacific Journal of Natural Science Vol. 17, (Special Edition).
Raghavan, K., Kishore, VVN. (2001). “Action Plan for Providing 100% of the Energy Requirements of Lakshadweep Islands from RES” Proceedings of the International Conference on Renewable Energies for Islands - Towards 100% RES Supply, Crete, Greece, 14-16 June 2001.
Samso Energy Company (SEC), 2003, Fact Sheets
Sauturaga, M. (2003). Project Manager, Office for the Promotion of Renewable Energy Technologies, DOE, Govt of Fiji. Personal communication, July 2003.
Seluka S., Panapa T., Maluofenua S., Samisoni, Tebano T., (1998). A preliminary listing of Tuvalu Plants, Fishes, Birds and Insects' by The Atoll Research Programme, University of the South Pacific, Tarawa, Kiribati.
Sharma, S.D., Duffy, G.J., Edwards, J.H. (2000). Survey of Renewable Energy Utilisation and Development Potential in Oceania. CSIRO Energy Technology.
Solarbuzz (2003), Photovoltaic Industry Statistics: Costs http://www.solarbuzz.com/StatsCosts.htm
SOPAC. (2002a). Country Profiles – Tuvalu. SOPAC
SOPAC. (2002b). Country Profiles – Fiji. SOPAC
SOPAC. (2002c). Country Profiles – Tonga. SOPAC
SOPAC. (2002d). General Background Document of SOPAC Countries (Fiji, Kiribati, Samoa, Tonga, Tuvulu, and Vanuatu Islands). SOPAC.
Stephen, F. and Haug, O. (1994). Wave Climate of the Southwest Pacific. SOPAC Technical Report 206.
Taape, I. (2003). Energy Planner, Govt. of Tuvalu. Email communication, July 2003
Tukunga, T. (2003). National Energy Planner, Govt of Tonga. Personal communication, July 2003.
Tuvalu Electricity Corporation (TEC). (2002). Operations Report Jan-July 2002. Tuvalu Electricity Corporation.
Windicator. (2003). Wind Power Monthly, Denmark.
World Climate. (2000). http://www.worldclimate.org.
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ANNEXURE 1 SAMSOE - DENMARK'S RE ISLAND
In 1996 the Danish government held a competition in which islands had to make a plan for reaching 100% renewable energy supply within 10 years. The island of Samsoe made the best plan and won this competition. In autumn 1997, Samsoe was appointed by the Ministry of Energy as "Denmark’s Renewable Energy Island". The objective was that Samsoe would become self-sufficient with renewable energy within a decade. The major energy needs of Samsoe are electricity and heat for space and water heating. It was proposed that this would be met from the RE technologies given in Table 33.
Table 33 Technologies for Samsoe’s 100% RE Plan # Energy Technology Usage source 1 Solar Photovoltaic (SPV) Individual plants Heating Panels Individual plants, District heating 2 Wind Wind turbines on land Individual plants grid connected Off-shore wind turbines Grid connected to mainland 3 Biomass Wood-chips, Straw Individual plants, District heating Landfill gas Individual plants, District heating Farm-based biogas plants Individual plants, District heating 4 Heat recovery Waste heat from diesel District heating engines on ferries Heat pumps Individual plants
Annual plans made for each of the 10 years from 1997 to 2007 are given in Table 34.
Table 34 Energy Activities in Samsoe’s 10−year RE plan YEAR RENEWABLE ENERGY ACTIVITIES 1998 & · About 50 thermal solar units 1999 · About 20 biomass boilers, like pellet burners, wood-chips boilers and grain boilers · About 20 heat pump units, mostly soil heat plants 2000 With the erection of 11 new 1 MW wind turbines, the island will take a great step towards being self sufficient with renewable electricity. · 75% of the electricity consumed at the island will be produced by wind turbines. · A landfill biogas plant will also begin production in the year 2000. Methane gas will be used as fuel in a combined heat and generator plant. 2001 The first new areas, where district heating will be implemented are: · Nordby/Mårup, which will be heated by a combined straw and wood-chip boiler, together with 2500 m² thermal solar panels. · Ballen/Brundby, which will be connected to the existing straw-boiler plant in Tranebjerg. This plant will later on be supplied by a biogas plant. 2002 The transport sector is very difficult to convert to renewable energy. To compensate for that, offshore wind turbines will produce the same amount of energy as consumed in the transport sector. This energy can later on supply electric cars and hydrogen fuel cell cars: ______K. Raghavan, FREI Page 88 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga”
YEAR RENEWABLE ENERGY ACTIVITIES cars: · 10 offshore wind turbines will be erected at Paludans Flak south of Samsoe. Each wind turbine will have a power output at 2.5 MW. 2003 District heating will be implemented in further two areas: · District heating in Kolby Kås, Kolby and eventually Hårdmark. The heating supply comes from a bio-mass boiler-plant in a combination with surplus heat from the ferry in Kolby Kås. This will be the first plant in the world utilising surplus heat from ferries for district heating. · A local heating network in Orby will be supplied from an existing straw-boiler at the estate of Brattingsborg. 2004 In the year 2004 biogas plants will be established, producing hot water for district heating and electricity. The planned district heating areas are: · District heating at Besser, Langemark, Torup and Osterby. The heat shall be produced at a biogas plant and a biomass plant. Possibly the district heating area is divided into 4 areas for each village. · The existing district heating system in Tranebjerg, Brundby and Ballen will be extended by a biogas plant. 2005 In the year 2005, a hydrogen plant will be established (to separate water into hydrogen and oxygen). The plant will be powered by electricity from the offshore wind turbines. The hydrogen will then supply the transport sector. The plans are to: · Establish a hydrogen plant including a filling station. · Convert petrol cars to be driven by hydrogen. The cars will be able to run on both petrol and hydrogen. 2006 Neighbourhood district heating uses smaller plants for village communities, usually supplied from nearby farms with existing boilers and a potential or surplus production of bio-mass. · Neighbourhood district heating plants can be established in Tanderup, Hårdmark and Pillemark. · Island farmers will begin to deliver wood-chips from their own energy willow plantations. 2007 In year 2007 ten years have passed and the introduction of renewable energy will continue in the following years. The objective for 2007 is: · 100 % renewable electricity. · 60-80 % of heating needs met by renewable heating. · 15 - 20 % of transportation supplied directly by renewable transport energy (fuel cell and electricity).
In autumn 2003, at the half-way mark in the 10 year RE plan, Samsoe has managed remarkable achievements. Most elements of the plan are installed and working. Some of the targets have even been exceeded due to the overwhelming interest of the local population. The installations from 1997 include: · Around 100 thermal solar units (only 50 were planned) · Over 100 biomass boilers (only 20 planned) · About 30 heat pump units (only 20 planned) · Eleven 1 MW wind turbines on land · One landfill biogas plant with a CHP plant · Ten offshore wind turbines of power output at 2.3 MW each
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The only element in the plan that has not been achieved till 2003 is the recovery of waste heat from the ferries, to be used in district heating plants. The technology for doing this is quite simple and the company operating the ferries is interested in the project. However, they want 50% of the initial investment in the equipment to be subsidised and this has been difficult to arrange under the present circumstances in Denmark. The owners of the houses near the ferry terminal at Kolby Kas have also not shown much interest in a district heating plant since they have their own individual heating systems.
The percentages of energy consumption that Samsoe gets from renewable energy in 2003 is given in the Table 35.
Table 35 Amount and % of energy from RE on Samsoe in 2003 Sector Total Demand (million kWh) from RE (million kWh) from RE (%) Heat 58.0 33.2 57.2 % Electricity 26.2 27.0 103.1 % Transport 52.9 75.0* > 100 % * Electricity produced by off-shore windfarm to offset fossil fuels used by the transport sector. Source: SEC, 2003
As a result of these renewable energy installations, Samsoe has managed to reduce their CO2 emissions from the 1997 levels by 140%. This high figure (over 100%) is because the electricity from the off-shore windfarm (75 million kWh/year) is exported to the mainland and reduces electricity production from coal fired power plants.
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ANNEXURE 2 CAMPAIGN FOR TAKE-OFF
In December 1997 the European Commission adopted a White Paper for a “Community Strategy and Action Plan, Energy for the Future : Renewable Sources of Energy”. A target of 12% contribution from renewable energy sources was indicated.
RE was seen as an important method to achieve the Community's CO2 reduction goal, to reduce dependence on energy imports and to provide business opportunities.
The White Paper contained the “Campaign for Take-Off” (CTO) as a key element in the strategy. Public awareness, public support programs and public relations activities would be used to focus on the objectives of the CTO and stimulate private investment in RES. The Campaign for Take-Off was planned to run for 5 years (1999-2003) promoting the development of key RES sectors. During these 5 years the CTO aimed for the following RE technologies:
· 1,000,000 PV systems · 15 Million m2 solar thermal collectors · 10,000 MW of wind turbine generators · 10,000 MWth of combined heat and power biomass installations · 1,000,000 dwellings heated by biomass · 1,000 MW of biogas installations · 1,000,000 tons of liquid biofuels · 100 communities aimed at 100% RES supply
100 communities aiming at 100% RES supply
The last stated goal of the CTO "100 communities aiming at 100% RES supply” was looked upon as a way to optimize the available potential of renewable energy technologies by using them together in integrated systems for local power supply or in dispersed schemes for regional power supply. It could become a benchmark for the implementation of decentralized energy supply. A number of pilot communities, regions, cities and islands that can aim for 100% power supply from RES have been identified. Some of the participants of the CTO are listed in Table 36. These communities differ widely in their energy system characteristics and resource
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availability, climatic conditions and building styles, size, population density and standard of living.
Table 36 Campaign for Take−off − 100% RE communities NAME OF PROGRAM COUNTRY SECTOR PROMOTER "Mission Environment" in the France RES Municipality of Rennes municipality of Rennes VE-Organisation Aerø - AerØ: A Renewable Energy Island Denmark RES Aerøskoebing Kommune Aiming for a Renewable Energy: Lund Sweden RES The municipality of Lund Office of Environmental Climate protection in Heidelberg - Germany RES Protection, Energy and working together against pollution Health Promotion Furth. A Place in the Sun Germany RES Community of Furth Furth. A Place in the Sun. Kick-off for Germany Solar PV Community of Furth PV implementation, Phase II Fossil Fuel Free Uppsala Sweden RES Municipality of Uppsala Fossil Fuel Free Växjö Sweden RES Municipality of Växjö District Board Chemnitz, Integration of RES in the revitalisation Consortium of 6 of European cities: "EU competition for Germany RES municipalities, German, bioclimatic urban redevelopment" Austrian & Hungarian Ministries, EUROSOLAR Kristianstad, fossil fuel free Sweden RES Municipality of Kristianstad municipality Lüchow: Planning the Changeover to Lüchow- District Luechow - RES RES within 10 to 15 Years Dannenberg Dannenberg Malmö Bo01 Residential and Office Sweden RES The City of Malmö Area in the Western Port Powys' renewable energy development United Powys County Council, RES plan Kingdom Wales Department of Health and Renewable energy sources and rational Germany RES Environment, Munich City use of energy in the city of Munich Council Resuelva, renewable energy sources in Provincial Authority of Spain RES the province of Huelva Huelva Samso The Danish Renewable Energy Samsoe Energiselskab Denmark RES Island Smba Sustainable islands programme Italy RES Ministry of Environment Säffle - A Municipality with Minimized Sweden RES Säffle Municipality Use of Fossil Fuels Municipality of Gotland: A Renewable Sweden RES Municipality of Gotland Energy Island in the Baltic Sea Écija, sun city Spain RES Municipality of Écija Övertorneå: RE for Europe Sweden RES Municipality of Övertorneå
While examining the prospects for integrating renewable energy technologies, the following were found to be most relevant: · energy consumption density per area unit, compared to RES availability · availability and type of energy infrastructure ______K. Raghavan, FREI Page 92 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga”
· power consumption pattern · size
A first categorization of communities was based principally on the comparison of the energy consumption density with RES availability. In each such category, subdivision according to type and size of the community was also made:
1. Urban communities: Solar input smaller than the energy consumption density. Limited availability of other RES. Examples: blocks of buildings, neighbourhoods in residential areas, villages, towns, large cities. 2. Rural communities: Solar input in range of energy consumption density. Usually, significant availability of other RES (wind, biomass, hydro). Examples: small rural areas, provinces, regions. 3. Isolated communities: Solar input bigger or in range of energy consumption density. Usually, significant availability of other RES. None or weak interconnection with external electric grid. Examples: isolated areas, islands (small, medium, large), autonomous areas.
Another interesting finding of the CTO was that the type and the degree of development of the current energy infrastructure greatly influences the level of RES penetration. For example, in newly built communities, the energy infrastructure can be designed from the start to accommodate RES. On the other hand, the highly developed energy infrastructure in existing communities can prevent, for many years, major additions of RE into the energy supply system.
Other criteria defined by the CTO for the 100 communities were: · In each of the candidate communities the path for maximizing RES penetration should be specified. · In order to develop the actions required and to monitor progress, a strategy including schedules, priorities and players must be defined. · Local and regional authorities as well as regional energy centers have important roles to play in implementing this project. · Preference should be given to activities involving combinations of technology in such a way that such projects have the potential to cover the entire range from pre-feasibility study, through feasibility study and demonstration phase (mainly
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program financed), to large-scale implementation mainly with commercial financing.
RE Partnerships on Islands
The Campaign for Take-off also has goal for promoting RE Partnerships on several islands that are listed in the Table 37.
Table 37 RE Partnerships on Islands in the CTO NAME OF PROGRAM COUNTRY SECTOR PROMOTER Action Plan for Large Scale Deployment of Greece RES Hellenic Republic RES in Crete - Region of Crete Canary Islands Renewable Energy Programme Spain RES Cabildo Insular de Tenerife Diffusion Campaign for Solar Thermal Italy Solar Ázienda Speciale Systems with Natural Gas back-up Thermal AMG EL HIERRO Island, biosphere reserve, 100% Spain RES El Hierro Island RES supply Authority Renewable Energy Park for the Island of Greece RES Municipality of Corfu Thinalli
The Atlantic island of El Hierro which is a part of Canary Islands, Spain joined the RE Partnerships on Islands of the CTO with an ambitious plan for 100% RES supply, details of which are given in the next section.
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ANNEXURE 3 EL HIERRO IN THE CANARY ISLANDS, SPAIN
Table 38 Facts about El Hierro Area: 278 km2 El Hierro is one of UNESCO’s Biosphere Max. height: 1,501 m Reserves meant for preserving the Max. depth within the BR: -250 m Population: 9,600 particular natural and cultural values of Density: 34.9 around 400 regions all over the world.
Table 39 Annual energy demand Electricity consumption 19 GWh (1996), In the RE Partnership Declaration
22 GWh (2000) for El Hierro’s “100% RES Supply Electricity production 21 GWh (1998) Fuel for private transport 2.198 Ton (1998) Initiative” the “Cabildo Insular de El Fuel for industry, agricul- 11,612 Ton (1999) Hierro” (Island Council) declared ture and public transport Installed Power 8,285 MW (1998) its willingness to contribute to the implementation of the Campaign for Take-Off by way of clearly specified programmes and projects. Relevant parts of this declaration are summarized below.
The island’s Sustainable Development Plan of 1997 relies on: 1. Electricity supply from RES 2. Water deficit cover as a complementary and integral part of the 100% RES project (water-energy binomial) 3. Bioclimatic solutions and realizing the potential of solar thermal 4. Energy valorisation of biomass (wastes and effluents) 5. Introduction of an integral system of alternative transports 6. Elimination of the landscape and ecologic impacts derived from the energy system
The Island Government is collaborating with the Technical Institute of the Canary Islands (ITC) in a project to cover the electric energy demand of the island with 100% RES by 2005, the idea of which goes back to 1986. 100% RES electricity supply will be guaranteed by a combined wind and pumped-hydro hybrid using artificial lakes. The system consists of a 15 MW wind farm whose electricity pumps water to a reservoir 600 meters above sea level having a capacity of 250,000 m3 . This water is used to drive the hydro turbines-and then flows into another reservoir next to the hydro-electric power plant having the same capacity. The wind electricity now pumps water from this lower reservoir to the upper one in a closed cycle. A reverse osmosis, sea water desalination plant adds enough water to make up for the
______K. Raghavan, FREI Page 95 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” evaporation losses and also supply irrigation water for farms on the island’s foothills where fruits and vegetables are grown for domestic consumption and for export. Different sizes of wind turbines are being studied for the 15 MW windfarm.
The savings expected from the replacement of the conventional system to the wind- hydro plant are given in the Table 40.
Table 40 Energy Savings from Wind−Pumped Hydro system Conventional System Wind-Hydro System El Hierro also has a Electric Energy, Mh=58,244 Wind Energy, MWh=43,357 “zero waste” initiative Consumed Fuel, Tm=15,143 Fuel Savings, Tm=11,272 under which biogas CO2 Generation, Tm=47,760 CO2 not produced, Tm=35,552 SO2 Generation, Tm=272 SO2 not produced, Tm=203 is produced from NOX Generation, Tm=990 NOX not produced, Tm=737 animal waste and sewage. A biogas digester has been installed in a farm sponsored by the local Island Council.
The first demonstration projects for an alternative transport system being implemented by the Island Council in cooperation with the local transport co- operative are based on: · Incorporation of a hybrid bus to the local fleet. At the beginning its use will be limited to the airport-capital transfer. One among the various options involves the use of biogas as fuel. · Incorporation of an electric, battery-powered minibus in the El Golfo area, for a mixed tourist-public use. It would rely on a photovoltaic station for its recharge. · Development and consolidation of an extensive pedestrian network. · Incorporation of advanced information and management of the transport systems within the framework of the sub-programme “El Hierro- Digital Island”. · Development of an ingenious ticketing system for the optimisation of displacements in rural scattered areas, occasionally turning the private vehicle into collective transport, supported by electronic systems for the payment of displacements. This will favour an integrated system of rational use and energy saving in the transport sector. The objective is 30% reduction of energy used by the transport sector within 5 years.
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Table 41 Markets Prospects − solar panels on El Hierro Sector House- Tourist Swimming- TOTAL ITC has developed holder Sector pool market prospects Heating Estimated 1.024 115 1.420 2.559 for solar thermal market -m2 applications with the support of the Altener program. In order to promote solar thermal systems on the island of El Hierro, ITC has used a financial scheme and also worked on promotion, information, awareness campaigns, training and involvement of the local institutions and local population. Another big success was the creation of a local company to install solar thermal systems. ITC also carried out a study on the estimated market for solar thermal systems on the island results of which are shown in the Table 41.
Table 42 Yearly targets − solar panels on El Hierro 2.001 2.002 2.003 2.004 TOTAL Bioclimatic solutions and Estimation incorporation of RES in of m2 to 90 120 140 150 500 be installed buildings is carried out by the architectural division of the island’s Cabildo through a technical unit. This action is complementary to the new directives of the Canary Islands Government on RES and building issues.
To preserve El Hierro’s Biosphere Reserve status, all the actions of the 100% RES strategy have to be integrated with the environmental concerns. The main factors are: · Location of the wind farm after a thorough study of environmental impact. · Utilisation of the present installations and area of the thermal power station for the location of the pumping system and the main desalination plant. The storage system will be located in an existing natural hole, avoiding any movement of soil. · Water production from RES will avoid overloading the natural water tables, preserving the scarce resources available for the maintenance of valuable island ecosystems and recuperating the rural landscape. · In parallel with the project, impacts derived from infrastructures and aerial grids are being removed, especially in high ecological sensibility areas · Availability of autonomous systems based on renewable energy allows the limitation of environmental impacts within the core and most sensible areas of the Biosphere Reserve.
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ANNEXURE 4 FIVE EUROPEAN ISLANDS
The five European islands listed in Table 43 have made plans to reach 100% RE supply by 2020. Basic information about these islands is given in this section together with details of the RE sources and technologies that the islands plan to use.
Table 43 Five European Islands # ISLAND COUNTRY The 5 European islands were part of a EU 1 Hiiumaa Estonia project called “Cluster AL/2000/0013 - 100% 2 Gotland Sweden Renewable Islands” carried out from April 2001 3 Lemnos Greece 4 Achill Ireland to September 2002 under the ALTENER 5 Ithaka Greece program. The common objectives were: · Establish local plans in the selected islands for achieving 100% RE supply. · Motivate local communities to adopt strategies for RES deployment. · Analyse the main technical and non-technical issues related with the large-scale development of RES in geographically autonomous systems. · Widely disseminate the results of the project and try to motivate other islands towards the target of 100% RE supply.
To achieve these objectives, the partners undertook horizontal” tasks aimed at: · Facilitating the exchange of information · Testing and communication of analytical tools and implementation practices · Promotion of synergetic effects and · Maximizing the results of the dissemination activities.
1. HIIUMAA in Estonia
The island of Hiiumaa with an area of about 1019 km2 is located in the eastern part of the Baltic Sea at a distance of 22 km from the mainland. The population of 11,500 inhabitants has started to decline during the last few years due mainly to economic reasons, although there has been a significant trend to enter a path of development. About 60% of the completely flat island is under forest cover while 23% of the total area is used for agriculture. Although agriculture has been growing fast, the main driving sectors of economy in Hiiumaa are fishing, fish processing and retailing. The energy sector is highly dependent on imported fossil fuels (and electricity) from the mainland. The RES is focused primarily on exploitation of the rich biomass
______K. Raghavan, FREI Page 98 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” potential for existing or planned district heating systems (household and industrial), together with the high wind potential (sandbanks and islets that are the present sites for offshore exploitation), The sustainable biomass exploitation is based upon the effective use of the indigenous resources, together with the actions that will reduce the energy cost for consumers. However, the prospects for the development of combined heat and power (CHP) plants are rather low due to the limited uses for thermal energy. The establishment of the new electric grid interconnection to the mainland (via Saaremaa island) will secure the power supply for both islands, offering the required infrastructure for exploitation of the wind potential. The Action Plan also proposes tapping the solar energy potential for producing domestic hot water for 5–6 months per year as well as innovative solutions for improving energy efficiency.
Table 44 RES Action Plan for the island of Hiumaa, Estonia RES Years 2000 2005 2010 2020 Wind farms 0,15 MW 0,15 MW 1,15MW 4,5 MW Biomass, electrical - MW - MW - MW 1,2 MW Solar hot water 10 m2 50 m2 240 m2 1600 m2 (collector area) Biomass for heat 90 GWh 112 GWh 124 GWh 133 GWh Participation of RES 53% 62% 65% 72 %
2. GOTLAND in Sweden
The island of Gotland is located in the middle of the Baltic Sea. It is 175 km long and 50 km wide and has an area of 3140 km2 with a total population of approximately 58,000 inhabitants. Visby, the biggest town with 22,000 inhabitants, has been included in UNESCO’s World Heritage List. Agriculture and fishing are major sectors in the economy of the island, while the big forests account for a well organized wood processing industry. Since 1992 Gotland has become an eco-municipality, representing an environmental friendly profile, which is also reflected in the energy sector.
The island is interconnected to the mainland and has a large RES potential, comprising of significant wind and biomass resources. It is also one of the sunniest areas in Sweden. The RES Action Plan is based on diversified energy sources, including the exported wind produced electricity, various technologies for exploiting biomass (biogas, gasification-electricity production, co-generation, district heating,
______K. Raghavan, FREI Page 99 __ Case Study: “100% Renewable Energy Islands in Tuvalu, Fiji and Tonga” individual woodstoves of increased efficiency), significant penetration of heat pumps, exploitation of recycled energy (mainly in industry) and the prospects for using biofuels (ethanol, biogas) in the transport sector. The development of offshore wind farms for hydrogen production is also anticipated.
Table 45 RES Action Plan for the island of Gotland, Sweden RES Years 2000 2005 2010 2020 Wind farms 75 MW 130 MW 250 MW 1100 MW Photovoltaic - MW 0,25 MW 0,6 MW 3 MW Biomass CHP - MWe - MWe - MWe 30 Mwe Solar hot water (collector 2000 m2 5000 m2 15000 m2 50000 m2 area) Biomass individual/DH 208 GWh 300 GWh 340 GWh 510 GWh Heat pumps 15 MWe 20 MWe 25 MWe 25 Mwe Recycled Energy 20 GWh 50 GWh 75 GWh 145 GWh Ethanol transport - GWh - GWh 30 GWh 175 GWh Biogas transport - GWh - GWh 10 GWh 150 GWh Participation of RES 11% 18% 29% 100%
3. LEMNOS in Greece
The island of Lemnos, is located in the Northern Aegean Sea, and has a population of 18,000 living on an area of 476 km3 . The island follows the general island type of the Northern Aegean complex that is a semi-mountainous area, with agricultural activities mainly of wheat and vineyards. The eastern part of the island is one of the major wetlands of Greece, an area of great ecological interest and part of the Natura 2000 network. The local industry concentrates on agricultural products processing, while the main local activity is services connected to tourism on the island.
The energy system is autonomous, with limited prospects for connection to the mainland due to geological constraints and strong undersea streams. Electricity is generated mainly by engines using diesel and heavy oil, while heating and transport needs are provided by oil. The RES prospects of the island are considered very high, concentrating on the solar and wind potential, while biomass exploitation refers to a significant amount of agricultural residues together with the traditional wood-stoves and the development of energy crops. The philosophy of the Action Plan is to integrate RES into economic and social structure of the island taking into account the landscape and cultural values. Thus the Action Plan is founded on a combined energy, water and waste management perspective that includes wind-desalination
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Table 46 RES Action Plan for the island of Lemnos in Greece RES Years 2000 2005 2010 2020 Wind farms 1,14 MW 4,14 MW 6,14 MW 14,14 MW Photovoltaic - MW 0,04 MW 0,2 MW 2 MW PSU - MW - MW - MW 4 MW Biomass EL - MW 0,25 MW 2,25 MW 4,25 MW Solar hot water 7400 m2 11100 m2 14800 m2 17600 m2 Biomass for heat 17 GWh 21 GWh 25 GWh 31 GWh Wind Desalination - kW 350 kW 700 kW 700 kW Solar Cooling - RT 100 RT 200 RT 200 RT Participation of RES 13% 27% 47% 76 %
4. ACHILL in Ireland
Achill is the biggest island of the coast of Ireland, with a land area of approximately 132 km2 . and a population of 2,751 inhabitants (1996 Census). It is linked to the mainland by a swing-bridge. The island has some mountainous areas following the coastline which have been designated as areas of conservation or areas of scenic significance. However, nearly 87% of the land is bog and peat land that limits the agricultural activity on the island. The population is mainly involved in rural activities and services, and fishing. There was a long economic decline until 1991 but since then the situation has been improving, largely due to increased employment provided by the tourism industry
The energy sector shows absolute dependence on fossil fuels imported from the mainland, together with the traditionally exploited local turf. A critical factor for the exploitation of RES on the island is the very high wind potential, with an average wind speed of 8.5 m/s. A systematic intervention for upgrading the weak local electricity system would make Achill a major renewable electricity producer (4% of the total Irish consumption), while there are long-term prospects for tidal and wave power. The development of solar water heating systems is related to the tourism sector, while the building heating needs will be increasingly covered by heat pumps.
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Table 47 RES Action Plan for the island of Achill in Ireland RES Years 2000 2005 2010 2020 Wind farms - MW 0,2 MW 1,7 MW 5 MW Wind - Offshore - MW - MW - MW 13,2 MW Tidal - MW - MW - MW 0,4 MW Solar hot water (collector 3 m2 29 m2 122 m2 732 m2 area) Heat Pumps - MW 1 MW 3,3 MW 16,8 MW Participation of RES - % 9% 28% 110 %
5. ITHAKA in Greece
Ithaka is among the small Islands of the Ionian Sea complex, having a land area of 92 km2 and a population of 3,000 inhabitants. Similar to the other Ionian islands, Ithaka has no high mountains and the terrain is hilly with small fertile plains. Southern winds bring abundant rainfalls making the climate mild and very humid. The island is noted for its natural beauty and its long history and cultural tradition. The island’s development profile is influenced by the proximity of the semi-urban island of Kefallonia. They are both well placed since they are close to the Greek mainland and to western Europe, thus forming a convenient stepping stone, in particular between Greece and Italy. These factors have favored the development of tourism which has become a very dynamic sector of the local economy, along with agriculture and services.
The island is interconnected with the mainland for its electricity supply, while the heating needs are mostly covered by imported oil. Therefore, it presents a high dependence on the mainland and on conventional fuels. The prospects for increasing RES supply are based principally on improved biomass use in the domestic sector, exploitation of wind energy up to approximately 5 MW and increased penetration of solar collectors.
Table 48 RES Action Plan for the island of Ithaka in Greece RES Years 2000 2005 2010 2020 Wind farms - MW 1,8 MW 4,8 MW 8,8 MW Photovoltaic - MW 0,4 MW 0,7 MW 1,2 MW Solar hot water (collector 7400 m2 11100 m2 14800 m2 17600 m2 area) Biomass for heat 1,2 GWh 3,2 GWh 3,8 GWh 4,5 GWh Participation of RES 10% 46% 79% 118 %
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ANNEXURE 5 LAKSHADWEEP ISLANDS IN INDIA
The Lakshadweep group of islands in the Arabian Sea consists of 10 small and medium sized inhabited islands and several uninhabited ones lying about 400 km off the south-west coast of mainland India. All the coral islands are low-lying and covered with coconut palms. The main occupations are fishing, fish processing and tourism. Tourism is being developed in a very controlled way so that the fragile ecological balance in the islands is not disturbed. Foreign tourists are allowed to visit only one island while four islands are open for Indian tourists.
In May 2001, the Lakshadweep government declared its intention to change over to 100% RES over the next 5-years. The Indian Ministry of Non-conventional Energy Sources (MNES) is expected to play a leading role in providing funds for this transition to 100% RES. An Action Plan for introducing RES solutions on the islands in a phased manner was developed for reaching 100% RES in all the Lakshadweep islands by the year 2005. This plan considered the energy consumption, the power generation mix, the renewable energy resources available and the technologies that could be used.
In 2001 the total electricity consumption on the 10 islands was estimated at 9.46 MWh/yr, most of it produced by 9.37 MW of diesel generators using diesel fuel brought from the mainland in 200 liter barrels. Three small wind generators, a biogas plant, several 100 kWp SPV power plants and a 250 kW biomass gasifier have been installed. Electricity generation and consumption figures for each island are given in Table 18.
Table 49 Power generation and consumption in Lakshadweep ELECTRICITY DG SET SPV WIND BIOMASS NAME OF CONSUMPTION CAPACITY POWER ELECTRIC GASIFIER ISLAND 2000-01 2000-01 PLANT GENERATOR (MWh/year) (kW) (kWp) (kW) (kW) Minicoy 4,395 1,800 100 Kalpeni 140 750 100 Andrott 274 1,250 100 Agatti 181 1,020 100 Kavaratti 4,013 1,800 100 20 250 Amini 174 1,034 100 Kadmat 131 750 150 Kiltan 88 510 100
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ELECTRICITY DG SET SPV WIND BIOMASS NAME OF CONSUMPTION CAPACITY POWER ELECTRIC GASIFIER ISLAND 2000-01 2000-01 PLANT GENERATOR (MWh/year) (kW) (kWp) (kW) (kW) Chetlat 60 430 100 Bitra 7 24 25 Bangaram 2 74 60 20 TOTAL 9,464 9,368 1,035 40 250
Table 50 Coconut Biomass available for electricity generation COCONUTS BIOMASS BIOMASS for The coconut trees ISLAND PRODUCTION PRODUCTION ELECTRICITY provide biomass (million nuts/yr) (tons/yr) (tons/yr) Minicoy 2.8 5,243 2,356 for cooking and Kalpeni 2.8 5,262 4,073 for smoking fish Andrott 4.4 8,146 6,766 for export. Agatti 2.9 5,434 2,330 Kavaratti 4.9 9,152 7,730 Biomass from Amini 3.1 5,705 4,414 coconut trees Kadmat 3.0 5,531 4,596 available for Kiltan 1.6 2,940 2,333 Chetlat 1.8 3,329 2,762 utilisation in Bitra 0.8 1,515 1,031 gasifiers to Bangaram 0.0 - - generate Total 27.9 52,257 38,391 electricity was estimated from the total coconut production by substracting the amount used for smoking fish and for cooking. It can be seen in Table 19 that more than 38 tons of biomass is available every year for generating electricity. This quantity of biomass can generate 18.8 million kWh of electricity/yr that is double the total electricity consumption of all the islands in 2000-01. Therefore, there is sufficient biomass available to meet the electricity requirement of all the inhabited islands in Lakshadweep. Coconut oil was not considered for substituting diesel fuel in the power plants because it is edible and commands a high price on the mainland.
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Table 51 Solar and Wind resource data for Agatti Month Global solar Monthly mean Weibull A look at the solar and Radiation Wind speed parameter wind resources for (kWh/m2 /day) (m/s) 'k' Jan 5.127 3.4 1.20 Agatti, one of the two Feb 5.765 3.7 3.20 biggest islands, shows Mar 6.270 3.2 2.40 that they are Apr 6.043 3.9 3.50 May 4.984 4.3 2.10 complimentary due to June 3.926 8.9 3.30 the monsoon climate. July 3.779 8.9 4.90 The wind speeds are Aug 4.268 8.4 4.60 Sept 4.946 5.9 3.00 high during the monsoon Oct 4.682 3.7 2.00 months when the solar Nov 4.727 3.4 1.70 radiation is very low Dec 4.672 3.1 2.60 AVERAGE 4.932 5.1 2.9 (June to Sept), whereas during January to April we find high solar radiation and low wind speeds. This is an ideal combination for Wind-SPV Hybrid systems.
The RE technologies proposed for Lakshadweep are 1. Wind generators 2. SPV arrays 3. Biomass gasifier based IC engine-generators 4. Hybrid systems consisting of two or more of the above together with battery banks and power conversion systems 5. Thermal applications of gasifiers are being considered to increase the efficiency of utilisation of biomass presently burnt in open fires.
Two different hybrid solutions were proposed, one for the big islands and the other for the small islands:
1. Wind-SPV-Diesel Hybrid system These systems are ideal for the smaller islands like Bitra and Bangaram where the total DG set capacity may be less than 100 kW. The system includes a battery bank for storage and an inverter for converting the DC to AC. The wind generators used in these systems are mostly permanent magnet alternators made for battery charging. The inverters are bi-directional and can also charge the battery from the AC source available. Commercially available inverters for hybrid systems are fairly versatile and can perform all the functions of the control system.
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2. Wind-Diesel Hybrid system For the larger islands having DG power plant capacities of a few hundred kilowatts to megawatts, the SPV array and battery bank, which are the most expensive items, are best avoided. For these islands the best option is a pure Wind-Diesel hybrid. The wind generators used in such systems are standard induction machines connected to the AC bus of the DG power plant. To switch off the diesel gensets whenever there is sufficient wind speeds, and maintain grid stability, a supervisory control system is essential.
Both systems utilise the diesel genset for back-up, so it is proposed to use biomass instead of diesel to eliminate fossil fuel usage. Producing gas from a biomass gasifier using coconut waste will displace as much of the diesel fuel oil as possible (around 70% to 80%). The remainder of the diesel consumption is eliminated by using coconut oil to run the diesel engines, so as to reach 100% RE. Lakshadweep plans to use renewable energy equipment made in India except for the inverters and hybrid system controllers. The biomass gasifier has been developed by the Indian Institute of Science, Bangalore, with financial assistance from the Indian government, and is produced under license by manufacturers on the mainland.
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