KIRITIMATI ISLAND ELECTRICITY SECTOR
Scoping exercise
April 2014
Kiritimati Island Electricity Sector
About IT Power
The IT Power Group, formed in 1981, is a specialist renewable energy, energy efficiency and carbon markets consulting company. The group has offices and projects throughout the world.
IT Power (Australia) was established in 2003 and has undertaken a wide range of projects, including designing grid-connected renewable power systems, providing advice for government policy, feasibility studies for large, off-grid power systems, developing micro-finance models for community-owned power systems in developing countries and modelling large-scale power systems for industrial use.
The staff at IT Power (Australia) have backgrounds in renewable energy and energy efficiency, research, development and implementation, managing and reviewing government incentive programs, high level policy analysis and research, including carbon markets, engineering design and project management.
About this report
This report is a technical report examining the main electricity infrastructure on Kiritimati Island, and was commissioned by OPUS on behalf of the New Zealand Government‟s Ministry of Foreign Affairs and Trade.
It follows on from:
The July 2013 study, A Least Cost Analysis of electricity Generation Options for Kiritimati Island, by GIZ and SPC, and a joint EU/NZ mission to Kiritimati Island between 18 and 25 September 2013.
ITP would like to acknowledge all the MPLID staff who assisted in data collection for this report. In addition, ITP would like to thank the following people for their input and feedback on the draft report:
Kireua Kaiea, Ministry of Public Works and Utilities, Katerina Syngellakis, GIZ, and Kate Cushing, NZ MFAT
ii ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
OPUS
Client contract No.: 1-45998.00
IT Power reference: A0120
Kiritimati Island Electricity Sector
April 2014
Prepared by:
IT Power (Australia) Pty Limited Southern Cross House, 6/9 McKay St, Turner, ACT, 2612, PO Box 6127, O‟Connor, ACT, 2602, Australia. Tel. +61 2 6257 3511 Fax. +61 2 6257 3611 E-mail: [email protected] http://www.itpau.com.au
Document control
File path & name G:\Work\0Projects\A0120 OPUS Pacific Energy Summit Activity Design\1Deliverables\Kiribati
Author Philippe McCracken, Joe Wyder, Joshua Jordan
Project Manager Simon Franklin
Approved Simon Troman
Date 01 April 2014
Distribution level Final
Template: ITP REPORT Form 001 Issue: 04; Date: 17/03/14
ITP/ A0120 – April 2014 iii
Kiritimati Island Electricity Sector
This page has been intentionally left blank
iv ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
CONTENTS
LIST OF ABBREVIATIONS ...... 7 EXECUTIVE SUMMARY ...... 9 1. INTRODUCTION ...... 13 1.1. Location and geography ...... 13 1.2. Climate ...... 14 1.3. Water Resources ...... 15 1.4. Renewable energy resources ...... 16 2. ELECTRICITY SECTOR GOVERNANCE ...... 19 3. KIRITIMATI ELECTRICITY SECTOR OVERVIEW ...... 20 4. ZONE 1 ELECTRICITY GENERATION AND USE ...... 23 4.1. Overview ...... 23 4.2. London (Ronton) ...... 25 4.3. Tennessee ...... 29 4.4. Tabwakea ...... 30 4.5. Zone 1 Private generators ...... 31 5. ZONE 2 AND ZONE 3 ...... 34 5.1. Airport / Banana ...... 34 5.2. Captain Cook Hotel ...... 35 5.3. JMB Store ...... 37 5.4. Zone 3 Poland ...... 38 6. OPTIONS AND COSTS ...... 39 6.1. Metering survey and upgrades ...... 39 6.2. Capacity building of the utility ...... 40 6.3. Interconnect the three Zone 1 MLPID mini-grids ...... 41 6.4. Build a new Zone 1 power station near the main wharf ...... 42 6.5. Connect the private grids to the Zone 1 main grid ...... 43 6.6. Connect the planned residential expansion in Tabwakea ...... 44 6.7. Install a grid-connected PV array ...... 45 6.8. Install a wind turbine ...... 46 7. RECOMMENDATIONS AND NEXT STEPS ...... 47 APPENDIX A. GIZ REPORT ...... 50
ITP/ A0120 – April 2014 v
Kiritimati Island Electricity Sector
APPENDIX B. BIOFUEL FEASIBILITY STUDY ...... 51 APPENDIX C. TONGA PREPAYMENT METERING STUDY ...... 52
vi ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
LIST OF ABBREVIATIONS
$m Million dollars AUD Australian dollar (approx. NZD 1.10) CDM Clean Development Mechanism CNO Coconut Oil ENSO El-Niño Seasonal Oscillation EPU Energy Planning Unit EU European Union GIZ Deutsche Gesellschaft für Internationale Zusammenarbeit GmbH GoK Government of Kiribati ITP IT Power (Australia) Pty Limited KNEP Kirabati National Energy Policy KOIL Kiribati Oil Company kVA Kilovolt-Amperes kW Kilowatt, unit of power kWh Kilowatt-hour, unit of energy, (1 kW used for 1 hour) kWp Kilowatt peak (unit of power for PV panels tested at STC) LCA Least-Cost Analysis LCOE Levelised Cost of Energy MLPID Ministry of Line and Phoenix Islands Development, also known as „Linix‟ MPWU Ministry of Public Works and Utilities NZ New Zealand NZD New Zealand dollar NZMFAT New Zealand Ministry of Foreign Affairs and Trade O&M Operation and maintenance PUB Public Utilities Board PV Photovoltaic SPC Secretariat of the Pacific Community STC Standard Test Conditions (1,000 W/m2 irradiance, 25 °C cell temperature, Atmospheric Mass 1.5) UPS Uninterruptable Power Supply USD United States Dollar (approx. NZD 1.20)
ITP/ A0120 – April 2014 vii
Kiritimati Island Electricity Sector
EXECUTIVE SUMMARY
Kiritimati Island (2° N, 157° W), in Kiribati‟s Line Islands group, is the world‟s largest coral atoll and the largest of the 33 islands in the Republic of Kiribati. At 320 to 388 square kilometres (depending on tidal and sand movements), the island accounts for approximately 70 per cent of the country‟s total landmass. The island‟s population is concentrated in three zones: Zone 1, which includes London, Tennessee and Tabwakea; Zone 2, which includes Banana and the airport; and Zone 3, which includes Poland.
The Ministry of Line and Phoenix Islands Development (MLPID) is responsible for electricity provision on Kiritimati. MLPID supplied 1,800 MWh to its customers in 2012, consuming $810,000 worth of fuel, although approximately 18% of annual generation is unaccounted for. This could be due to several factors, although further investigation would be required to determine the root causes. Domestic customers are charged AUD 0.30/kWh, and commercial customers AUD 0.33/kWh, but the true cost of generation is likely in the order of AUD 0.50-0.60/kWh. Fee collection is a challenge, with a collection rate of only 60%.
Some private operators run their own generation systems and therefore pay the full cost of generation as, unlike grid-connected customers, they are not subsidised by the GoK.
The Indian Government funded the installation of a 4 kV network in London in 2013, as well as a new 400 kW generator and power station transformer. The remaining MLPID generation equipment and facilities on Kiritimati are in poor condition, with most generation assets nearing their end of life.
MLPID plans to interconnect its three Zone 1 mini-grids, namely London, Tennessee, and Tabwakea, as they account for approximately 90% of the electricity generated by the MLPID power stations. However, the electricity sector on Kiritimati is expected to change in the near future:
The GoK plans to allocate 300 new land lots in Tabwakea to resettle residents from Tarawa; A new fish processing facility is being considered for London, with investment from the GoK and the joint venture that owns the plant on Tarawa; The GoK has announced plans to encourage the residents of Banana, currently located on top of a freshwater lens, to resettle to a location next to the JAXA tracking station, approximately 2 km west (tentatively called New Banana) in order to reduce contamination of the lens; The airport is being redeveloped in Zone 2, and may present a good opportunity for considering adequate roof space and network capacity for a grid-connected PV system to reduce Banana‟s loads.
ITP/A0120 – April 2014 9
Kiritimati Island Electricity Sector
The EU‟s EDF-10 program will fund the installation of a 16 kWp PV/diesel hybrid system with battery storage on Poland, which is expected to meet the majority of its current electricity needs.
Any further intervention in the electricity sector should therefore be focused on Zone 1, as that is where most of the electricity on Kiritimati is consumed and where load growth is expected. An intervention in Zone 2 may be premature at this point, as doing so may make it even more difficult to resettle residents to New Banana.
In order to increase the reliability of the Kiritimati electricity sector and improve the level of service offered, several options are available:
1. The installation of prepayment meters on all residential and small business customers would improve cash flow at the utility and increase the rate of fee collection. Metering of all loads that are currently un-metered (e.g. street lights, some MLPID buildings) would allow an accurate assessment of line losses. Finally, installing fuel meters and kWh meters at the main power station would allow an accurate assessment of fuel efficiency of the generators. 2. Implement the institutional and capacity building activities for MLPID‟s utility division, as described in the 2014 GIZ least-cost analysis (LCA) report. Of particular use to MLPID would be a GIS mapping and aboveground marking of all its distribution assets. Other projects include developing a strategic planning document and energy plan for Kiritimati, energy awareness raising activities, and training of MLPID staff. An energy efficiency campaign is proposed as well; this would greatly benefit MLPID as the more electricity it sells, the worse its financial position (because it sells electricity at a loss). 3. Interconnect the three Zone 1 MLPID mini-grids. This would make future load forecasting easier, as the change in load on one mini-grid will be relatively lower on the new Zone 1 grid. A larger grid would also make it easier to connect renewable energy generation, in particular wind, which requires a relatively high load to be economical. Management of generation assets is also easier, as they would be centralized. Expansion of the grid is more cost effective, as there would be an 11 kV backbone running along the length of Zone 1, so future residential or industrial development is possible further from the main settled areas. 4. If the Zone 1 mini-grids were to be interconnected, MLPID may wish to consider building a new power station at the main wharf. This would provide a good opportunity to construct a purpose-built facility and install a generation fleet that is sized to meet the various load conditions in Zone 1. It would also free up land in London and reduce noise and atmospheric pollution there. 5. If the three Zone 1 grids were to be interconnected, there may be some benefit to extend connection to the private mini-grids too. This would free up those grids‟ operators from operating and maintaining their generators, and refocus their efforts on their core business
10 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
(education or hospitality). It would also reduce their electricity costs as the MLPID tariff is lower than the cost of diesel generation on Kiritimati, but the GoK would consequently be subsidizing more electricity and run at a higher loss. 6. The residential expansion in Tabwakea would need to be provided with electricity in order to make it attractive for settlement. If no electricity is available, people will settle wherever they can connect to the network, which may lead to population stress in some areas of the island. 7. A centralized 60 kWp grid-connected PV system would provide some benefit to the utility as it would reduce its noontime load and reduce fuel expenditures. However, for any real benefit, the system should be connected to the large Zone 1 grid rather than having several smaller systems on the three MLPID mini-grids. The PV system should be located in an area where future expansion is possible, and preferably be near the power station so that all generation assets are centralized. In the longer term, a large PV system (several hundred kWp) with energy storage may be possible. 8. A 200 kW wind turbine was found to be technically and financially feasible in a GL Garrad Hassan study, although the main challenges facing such a project revolve around its operation and maintenance. MLPID should improve its record of governance and maintenance before embarking on a wind scheme, so installing a wind turbine is not recommended in the short to medium term.
The table on the following page provides indicative cost figures for the above projects, as well as timeframes and an order of priority.
ITP/A0120 – April 2014 11
Kiritimati Island Electricity Sector
Table 1: Recommended projects, costs, timeframes and priorities
Project Est. cost Timeframe (incl Priority (NZD) tendering, shipping, installation)
Survey and meter all unmetered loads 10,000 6 months Early 2014
Meter generators (fuel and electricity) 10,000 2 months Early 2014
Prepayment metering 600,000 1 year Early 2014
Implement capacity building activities 2,000,000 2.5 years Mid 2014 identified in GIZ capacity building report
Hire technical assistance to manage all small 300,000 2.5 years Mid 2014 projects in GIZ capacity building report (and others, if necessary)
Interconnect the Zone 1 mini-grids 750,000 1 year Late 2014
Build a new Zone 1 power station 2,500,000 2 years Late 2014
Connect the planned residential expansion in 825,000 1 year Late 2014 Tabwakea
Install a small grid-connected PV system (60 150,000 9 months Late 2014 kW)
TOTAL for near-term expenditures 7,145,000
Install a larger grid-connected PV system (500 5,000,000 1.5 years 2017+ kWp) with energy storage
Install a wind turbine 1,250,000 1 year 2017+
TOTAL for long-term expenditures 6,250,000
12 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
1. INTRODUCTION
1.1. Location and geography
Kiritimati Island (2° N, 157° W), in Kiribati‟s Line Islands group, is the world‟s largest coral atoll and the largest of the 33 islands in the Republic of Kiribati. At 320 to 388 square kilometres (depending on tidal and sand movements), the island accounts for approximately 70 per cent of the country‟s total landmass. The island is approximately 3,300 km east of Kiribati‟s capital, Tarawa.
Kiritimati Island is characterised by its numerous subsidiary lagoons, tidal flats, partially hypersaline brine ponds and saltpans. As a coral atoll, it is composed of porous limestone bedrock which is capable of retaining only a limited amount of subsurface fresh water in the form of a freshwater lens. Kiritimati‟s low elevation (approximately 3 m above high tide) makes it particularly vulnerable to rising sea levels.
The island‟s population is concentrated in three zones: Zone 1, which includes London, Tennessee and Tabwakea; Zone 2, which includes Banana and the airport; and Zone 3, which includes Poland.
Zone 1 Zone 2
N
Zone 3 0 5 10 km
Figure 1: Satellite image of Kiritimati (source: Google)
ITP/A0120 – April 2014 13
Kiritimati Island Electricity Sector
1.2. Climate
Temperatures on Kiritimati Island are typical of those experienced in the tropics, ranging from 25 to 32 degrees Celsius. Fluctuations throughout the year are minimal with variations in temperature typically being more diurnal than seasonal.
Despite lying in the tropics, Kiritimati receives relatively low levels of precipitation with wide variability. The average rainfall on the island is 873 mm a year, and in dry years, it can be low as 177 mm.
Figure 2: Kiritimati annual rainfall, grey bars indicate transitional years, source: www.pacificclimatechangescience.org
Kiritimati Island‟s dry climate has made it susceptible to regular droughts that are made worse by the island‟s lack of vegetation and geological structure that consists of porous rock and thin soil. The consistently high levels of evaporation also make retaining fresh water on or within the atoll difficult, further contributing to the intensity of the island‟s frequent water shortages.
During the September 2013 mission, evidence of fire activity was seen in two areas but it was not ascertained if these were controlled burns
Figure 3: Part of the burnt area at the Decca water lens
14 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
1.3. Water Resources
0
1
2
3 km
Figure 4: Decca water lens
While Government policy is to reduce population pressure in Tarawa by encouraging movement to Kiritimati, limits to the practicability of this migration will eventually be reached. While there is ample land on Kiritimati, it is fresh water availability from the groundwater sources that restricts where development can occur and how much the island‟s population can grow. A moratorium has
ITP/A0120 – April 2014 15
Kiritimati Island Electricity Sector
been placed on developing the land above the Decca water lens (see Figure 4), as this is the island‟s major source of groundwater. The 2010 census reported a population of 5,586 and found rds that 2/3 of households on Kiritimati rely on the piped fresh water that originates from this lens, and roughly 1/3rd of households rely on their own groundwater wells. Only 1% of households relied on rainwater as their main source of drinking water. The two water lenses supplying London and the Zone 2 group are already estimated to be near the limits of sustainable extraction with an estimated population capacity of 6,000 (SPC, 2013).
1.4. Renewable energy resources
There are a range of renewable energy resources available in Kiritimati. However, this technical report‟s focus is on solar and wind.
1.4.1. Solar Kiritimati Island has a relatively high average global horizontal solar radiation, at 6.3 kWh/m2/day1. Cloud coverage is relatively constant throughout the year, so solar radiation does not vary much on a monthly basis (monthly averages remain within +/-10% of the annual average). However, the El-Niño Seasonal Oscillation (ENSO) affects solar radiation over longer terms, as a result of changes in the amount of cloud cover (correlated to the varying amounts of rainfall – see Figure 2).
Table 2: Average monthly horizontal solar radiation (in kWh/m2/day)1
Annual Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Average
6.06 6.35 6.37 6.13 6.08 5.98 6.17 6.61 6.80 6.69 6.42 5.99 6.30
8
7
6
5
4
3
2
1 Horizontalradiation (kWh/m2/day)
0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Figure 5: Average monthly horizontal solar radiation (in kWh/m2/day) for Kiritimati1
1 NASA Atmospheric Science Data Centre, 2013
16 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
For reference, monitoring of the west-facing 18 kWp photovoltaic (PV) system at the ANZ bank in London shows that the system averaged approximately 1,540 kWh/kWp/year for the first five years of operation. A south-facing array could be expected to produce slightly more, although Kiritimati‟s very close proximity to the equator means that it is less sensitive to panels being oriented in non-optimal directions than higher latitude locations (e.g. New Zealand).
Flat-plate PV technologies are the most practical form of solar energy conversion on the island, as concentrating technologies (solar thermal or concentrating PV) require low annual cloud cover (which may be possible in some years, but not in others). Flat-plate PV systems are also technically simpler than their concentrating counterparts (which require trackers to track the sun‟s position), and significantly simpler than solar thermal power generation technologies (which require extensive civil works and technical know-how to operate). Ground- and roof-mounted PV systems are common in the Pacific, and in the past few years ground-mounted mini-grid systems have been installed in remote islands. Installation of PV systems is straightforward and increasingly well-understood by technicians living in the Pacific, and maintenance on these systems is minimal, even if batteries are used to store energy (with sealed batteries requiring very little maintenance other than periodic testing).
1.4.2. Wind The island experiences a prevailing north-easterly wind. Wind measurements have been carried out at two locations since 2010 by the Energy Planning Unit (EPU) of the Ministry of Public Works and utilities (MPWU). In a 2012 report, wind energy consulting firm GL Garrad Hassan states that “The long term mean wind speeds at the locations of the London mast and Banana mast at a height of 34 m are projected to be 6.7 m/s and 6.6 m/s respectively”.
This level of wind speed is relatively high for a Pacific island located so close to the equator. GL Garrad Hassan estimated that a de-rated 200 kW wind turbine connected to an 11 kV backbone transmission line would generate around 715 MWh per year, or roughly 40% of the island‟s annual electricity consumption. The underlying assumption is that the Zone 1 and Zone 2 grids are all interconnected so that the loads are high enough for the turbine to operate while keeping the diesel generators at the power station sufficiently loaded.
The type of turbine that is used needs careful consideration that takes into account the physical environment in Kiritimati (hot, humid, salt-laden air) and the logistical constraints of the island. GL Garrad Hassan admits that the turbine used in its modelling (Enercon E33) is no longer manufactured and may prove difficult or impossible to procure, and that the construction of that turbine would be logistically challenging. Other turbine models (e.g. the tilt-down 200 to 275 kW Vergnet turbines) would likely be more suited to Kiritimati‟s situation. Vergnet turbines have been installed in numerous locations in the Pacific, as they have been designed to operate in tropical marine conditions. Furthermore, they may be transported in shipping containers, making the logistics of a wind project easier, and as they do not require the large cranes that other turbines do for installation, they are easier to assemble than turbines from competing manufacturers. The
ITP/A0120 – April 2014 17
Kiritimati Island Electricity Sector
capital costs of a wind project (as given by the GL Garrad Hassan report) are comparable to those of flat-plate PV project of the same capacity.
Wind power requires less land than competing renewable energy technologies available to Kiritimati (for the same amount of energy generated), making it an attractive proposition for increasing the share of renewables into the grid. However, the challenges facing wind energy integration are centred around maintenance of the turbine; the lack of maintenance of the older diesel generators and windmill water pumps on Kiritimati indicates that a wind project may suffer from maintenance problems as well, potentially jeopardizing the success of the wind project.
1.4.3. Other Coconut palms are widespread, though mostly untended, and coconut husks are used as a cooking fuel. There is a 51 km2 state-owned coconut plantation in the island‟s east, though the plantation‟s output has dropped significantly in recent decades and is in need of replanting. Some replanting activity was observed near the Poland water lens.
The Biofuel Feasibility Study Kiritimati Island, (Zieroth, 2012) indicated the copra resource for the three Line Islands (Kiritimati, Tabuaeran, Teraina) was around 1,500 tonnes per year, with production on Kiritimati itself by far the lowest of the three. The report states that the 825,000 litres of coconut oil (CNO) that could be produced by the copra resource would be equivalent to replacing approximately 750,000 litres of diesel. However, switching over to electricity generation from CNO would be a major undertaking, requiring political determination and significant effort and good management.
A biofuels project presents several risks and challenges (the requirement for new crops to be planted, reinvigoration and redevelopment of the copra industry, a mass harvesting of coconut crops on the island to ensure continuity of fuel supply, sound forward planning, very careful control of the quality of CNO that is fed into the generators), and relies on several financial assumptions to make the project financially viable. This includes that the government will set up a Dedicated National Authority for Clean Development Mechanism (CDM) funding, the project is eligible for CDM funding (which requires that it not be donor-funded), and subsidies from the Government of Kiribati (GoK) to the copra industry continue. The challenges remain the same for either a partial replacement of diesel by CNO or for a wholesale replacement.
The feasibility study admits that there may not be a financial advantage to switching over to CNO. Given the high level of risk involved in so many aspects of transition to CNO, not least of which is the large-scale redevelopment of a sector of the economy which will continually need to be subsidised by the GoK, ITP recommends that biofuels not be considered as an electricity generation source at this time.
Ocean technologies (wave power and tidal power) are still in their infancy and not yet widespread on a commercial scale. Given that Kiritimati is one of the most remote islands in the world and its
18 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
marine energy resource has not been accurately surveyed, relying on a cutting-edge technology for power generation would not be financially prudent. Marine energy technologies are unlikely to be practical on Kiritimati for at least several years, if not decades.
Kiritimati has no hydropower or known geothermal resource.
2. ELECTRICITY SECTOR GOVERNANCE
The Energy Planning Unit (EPU), under the Ministry of Works and Utilities, (MPWU) is the government department that monitors the electricity sector and manages energy policies in Kiribati. Although the Public Utilities Board is responsible for electricity in Tarawa, the Ministry of Line and Phoenix Islands Development (MLPID) is responsible for electricity provision on Kiritimati.
Electricity tariffs on Kiritimati are AUD 0.33/kWh for commercial and business customers, with domestic customers paying slightly less at AUD 0.30/kWh. Business customers include small shops, whereas commercial customers are composed of larger private consumers and government buildings (e.g. airport, hospital, schools, motor pool). Although the electricity tariff is set at AUD 0.30-0.33/kWh, MPWU estimates that the true cost of electricity is between AUD 0.53/kWh and AUD 0.67/kWh.
The GIZ LCA report indicates that the total amount of energy generated by MLPID on was approximately 2,210 MWh, consuming AUD 810,000 worth of fuel. However, only 1,800 MWh were supplied to customers, meaning that approximately 18% of annual generation is unaccounted for. This could be due to several factors, including distribution losses, unmetered loads (e.g. power station auxiliaries, street lights, water pumps, MLPID buildings), poor record- keeping, electricity theft, or faulty metering equipment. Further investigation would be required to determine the root causes. GIZ reports that in 2012 MLPID collected approximately AUD 185,000 from electricity sales, which equates to only 15% of the annual costs of generation of AUD 1,230,000. There appears to be a discrepancy between the GIZ data and the MLPID data, which may be due to an error in the MLPID data of 680 MWh (please see Table 3).
ITP/A0120 – April 2014 19
Kiritimati Island Electricity Sector
Table 3: Generation and billing figures for 2012
Amount Amount in AUD Source in MWh
Generation 2,210 1,230,000 GIZ LCA report
Supplied to 1,800 540,000 - 600,000 GIZ LCA report customers2
Billed 1,000 310,000 MLPID data (corrected)
Collected 600 185,000 GIZ LCA report
Some private operators (e.g. JMB service station, supermarket and workshop) run their own generation systems and therefore pay the full cost of generation as, unlike grid-connected customers, they are not subsidised by the GoK.
More detail on the institutional context of the Kiritimati electricity sector is given in the GIZ report, Kiritimati Island Energy Project: Institutional and Capacity Building Aspects, February 2014.
3. KIRITIMATI ELECTRICITY SECTOR OVERVIEW
Electricity generation on Kiritimati is grouped into three main areas: Zone 1 (London), Zone 2 (Banana), and Zone 3 (Poland). Each zone is composed of one or more public mini-grids owned and operated by MLPID, in addition to several facilities which self-generate their electricity using their own diesel generators.
Table 4: Summary of public mini-grids on Kiritimati
Annual generation Annual sales Min/max loads Gen. Capacity Zone Mini-grid 3 4 (MWh) (MWh) (kW) (kW)
London 1,540 610 176 / 229 250, 400
Zone 1 Tennessee 140 80 16 / 25 50
Tabwakea 300 215 25 / 70 150
Zone 2 Banana/Airport 220 705 20 / 50 180
Zone 3 Poland N/A 8 N/A 60
2 There was an error in the MLPID data, which could mean that this figure is inflated by 680 MWh. If so, there would be a large amount of electricity that is unaccounted for (assuming the billing and generation figures of 1,000 MWh and 2,210 MWh are correct) 3 Data taken from GIZ report 4 Data taken from MLPID sales records 5 Data from 2007. This may account for the large disparity between generation and sales figures
20 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
Table 5: Summary of facilities which self-generate their electricity
Annual generation Annual use Min/max loads Gen. Capacity Zone Facility (MWh) (MWh) (kW) (kW)
Spivey Secondary 6 25 N/K 3 / 4 25 School
St Francis High Zone 30 N/K 4 / 6 25 1 School Crystal Beach Motel 30 N/K 4 / 7 35
Rawanibakoa 30 N/K N/K N/K
JAXA satellite N/A N/K N/K N/K tracking station
Zone JMB Service Station 35 N/K 10 / 25 100 2 Captain Cook Hotel 220 N/K 20 / 65 100
EU-funded weather N/K N/K N/K 20, 20, 20 station
JAXA satellite tracking station Airport Crystal Beach Motel Spivey School Captain Cook Resort Rawanibakoa JMB Store St Francis School Banana
Tabwakea Zone 2
Tennessee Zone 1 0 2.5 5 km
London
Figure 6: Satellite view of Zone 1 and Zone 2, with MLPID grid labelled in white and private facilities in black (source: Google)
MLPID plans to interconnect its three Zone 1 mini-grids, namely London, Tennessee, and Tabwakea, as they account for approximately 90% of the electricity generated by the MLPID
6 N/K: Not Known
ITP/A0120 – April 2014 21
Kiritimati Island Electricity Sector
power stations. However, the electricity sector on Kiritimati is expected to change in the near future:
The GoK plans to allocate 300 new land lots in Tabwakea to resettle residents from Tarawa. This will significantly increase the load on the Tabwakea mini-grid; A new fish processing facility is being considered for London, with investment from the GoK and the joint venture that owns the plant on Tarawa. In its LCA report, GIZ states that if it is of the same scale as the facility on Tarawa, the loads at the London power station are expected to increase between 250 kW and 600 kW (if the facility is connected to the London mini-grid. Note that the facility on Tarawa generates its own electricity as the owners find the mains power too unreliable for their operations). MLPID should take care before agreeing to providing the fish plant with electricity; at current tariffs, which are well below the cost of generation, any additional unit of electricity sold will incur further financial losses on MLPID. A lack of financial viability may lead to inadequate maintenance, meaning that there is a risk that blackouts become more frequent as generation assets are not maintained. The consequence would be that the fish processing plant needs to self- generate in order to have a reliable source of electricity, making it less profitable, as the true cost of generation is higher than the MLPID tariff. MLPID would be left with a large excess of generation capacity that it would no longer need. Fisheries officials at SPC believe that the development of the fish processing plant is unlikely to occur in the next 3-5 years, as it is contingent on the success of the Tarawa facility; The GoK has announced plans to encourage the residents of Banana, currently located on top of a freshwater lens, to resettle to a location next to the JAXA tracking station, approximately 2 km west (tentatively called New Banana) in order to reduce contamination of the lens. However, to date the number of residents has not changed significantly and one of the churches is currently building a school in Banana, which will make it more likely that residents will remain; The airport is being redeveloped in Zone 2. This may present a good opportunity for considering adequate roof space and network capacity for a grid-connected PV system to reduce Banana‟s loads. The new airport is unlikely to significantly increase loads on the Banana mini-grid. Lastly, the EU‟s EDF-10 program will fund the installation of a 16 kWp PV/diesel hybrid system with battery storage on Poland, which is expected to meet the majority of its current electricity needs. However, it should be noted that demand is artificially depressed as electricity is available only 12 hours per day (nominally). In addition, the majority of houses have no refrigeration and many houses have few electrical appliances. The design for any system that provides 24-hour power may need to consider appropriate new diesel generation and control systems for potential load growth that may occur due to purchase of new electrical appliances such as refrigerators or freezers.
22 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
Any intervention in the electricity sector should therefore be focused on Zone 1, as that is where most of the electricity on Kiritimati is consumed (a situation which will be exacerbated by the addition of new homes and the fish processing centre). An intervention in Zone 2 may be premature at this point, as doing so may make it even more difficult to resettle residents to New Banana. The rest of this report will therefore focus on Zone 1, and provide some discussion on Zone 2 and 3 for information only.
4. ZONE 1 ELECTRICITY GENERATION AND USE
4.1. Overview
The Zone 1 generation area is composed of three main grids, operated by MLPID (London, Tennessee, and Tabwakea), and four private mini-grids (two schools and two hotels). The water pumps at the Decca lens are powered by PV, windmills, and a diesel engine, although some of this equipment requires repair and maintenance. The PV-powered filtration and chlorination facility appears to have been non-operational for many years. The majority of electricity is generated by the London powerhouse (approximately 75% of Zone 1 total generation), as shown in Figure 7.
5% 7%
14% London Tabwakea Tennessee Private facilities
74%
Figure 7: Breakdown of Zone 1 annual electricity generated, by mini-grid, Zone 1
ITP/A0120 – April 2014 23
Kiritimati Island Electricity Sector
Within the three MLPID mini-grids in Zone 1, the largest proportion of electricity sold in 2012 was to domestic customers. This situation may change with the addition of the fish processing plant in London (if similar to the plant in Tarawa, it would consume roughly 1,700 MWh per year, a near- doubling of current demand) and the new residential development in Tabwakea (the total number of domestic customers in Zone 1 is 399, so 300 additional houses would be expected to nearly double residential demand).
35%
45% Commercial Business Domestic
20%
Figure 8: Breakdown of MLPID electricity billing, by customer type, Zone 1
24 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
4.2. London (Ronton)
4.2.1. London grid London (Ronton) is the main load centre and the powerhouse is located near the small Bridges point wharf and the fish processing facility. The mini-grid has two 4kV underground transmission lines, one to the transformer near the MPLID office and the other out to the Hospital. Power is reticulated via an underground 415V distribution system.
Figure 9: London grid and aerial photo
Both images above are from before 2008 as the fish processing facility near the powerhouse is not shown. The MPLID office and ANZ bank near the north-west transformer are also not shown. The KOIL fuel storage depot just to the north of MPLID is where the London grid currently ends.
The Indian Government funded the 4kV grid upgrade, the two 4 kV/400V step-down transformers, the new powerhouse transformer and a 400 kW Cummins genset in 2013.
ITP/A0120 – April 2014 25
Kiritimati Island Electricity Sector
4.2.2. London generation The powerhouse roof is curved and the supporting structure is unlikely to be adequate for a PV system.
Figure 10: London powerhouse There are two operational gensets in the powerhouse and summary information is provided in the following table. Table 6: London Powerhouse operational gensets
Estimated full Brand kVA kW Installation load efficiency
Cummins Stamford 500 400 2013 3.8 kWh / litre Cummins 250 1999 3.6 kWh / litre
Figure 11: London gensets
26 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
The blue 400 kW genset is in good condition. The 250 kW yellow genset is nearing the end of its useful life.
The Biofuel Feasibility Study points out that “the London powerhouse has no synchronizing facility, ie only one generator can be operated at a time. With a nominal capacity of 250 kW and a temperature and age de-rating of at least 20% to 200 kW, it is obvious that the generator in London struggles to maintain load on a hot day”. The new 400 kW genset provided additional capacity after it was commissioned in 2013, although it is unclear if there is now synchronizing equipment.
There are three PV systems within the area of the London grid and one connected to the Tabwakea grid. Available information about them is summarised in the following table.
Table 7: London and Tabwakea PV systems
Number of Grid- Commisioning Average Site Type kWp Orientation Modules Connected Date generation
15 degrees 1,540 kWh / Yes, ANZ ~116 18 South from Feb-08 kW DC / London West year
Photowatt Both North TKSL 167 No? BPX47500 and South
10 degrees Internet Yes, 12 West of Access London South
reported as 10 15 degrees Church of Yes, 20 but more likley West from JC&LDS Tabwakea <4 North
ITP/A0120 – April 2014 27
Kiritimati Island Electricity Sector
Figure 12: PV Systems (clockwise from top left: ANZ, Church, TKSL and Internet Access)
4.2.3. London load The GIZ LCA report indicated that in 2012 there were 299 accounts on the London grid broken down as:
187 Residential, 68 Business, and 44 Commercial.
The 2010 Census indicated a population of 1,879 in London. Assuming all homes are grid- connected, this indicates an average of 10 people per residential meter. Average domestic consumption is roughly 1,190 kWh/year, or 1/7th of the use of a typical New Zealand household7.
The GIZ 2013 estimate for London‟s annual generation was 1,542 MWh per year, with a minimum load of 175 kW and a maximum of 230 kW. However, during the September 2013 mission a discrepancy between the various metering dials at the power station was noticed by ITP‟s engineer, which could lead to faulty load readings and inaccurate data being entered into station logbooks. This anomaly should be investigated and new fuel and load metering installed at the London powerhouse.
7 A typical New Zealand household uses 8,000 kWh/year. Source: Electricity Authority - Te Mana Hiko, Electricity in New Zealand, December 2011
28 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
4.3. Tennessee
4.3.1. Tennessee grid The Tennessee grid extends from just to the north of the KOIL facility to the Tennessee primary school. Tennessee was reported as having 19 residential, 14 business and 3 commercial accounts in 2007.
Figure 13: Tennessee looking south and the Tennessee school
4.3.2. Tennessee generation The powerhouse is located near the west side beach, about 400m south of the wharf.
Figure 14: Tennessee powerhouse and genset
The generator is a Nippon Sharyo 50 kVA and appears to be in a poor condition.
ITP/A0120 – April 2014 29
Kiritimati Island Electricity Sector
4.3.3. Tennessee load No load monitoring was undertaken at Tennessee. It is assumed that the wharf complex is connected to the Tennessee grid. The log books in the Tennessee powerhouse indicated a load of between 2.5 kW and 12.2 kW for the period in early August 2013. This is significantly less than the 16 to 25 kW (140 MWh pa) estimated for the GIZ LCA report. In 2007, the total metered load was about 114 MWh per year.
4.4. Tabwakea
4.4.1. Tabwakea grid The Tabwakea grid extends from the Church of Jesus Christ and Latter Day Saints in the south to about 500 m north-west of the Tabwakea water tank. In 2007, it was reported as having 186 residential and 8 business accounts.
Figure 15: Tabwakea grid area, (This image also shows the main wharf which is assumed to be connected to Tennessee’s grid).
30 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
4.4.2. Tabwakea generation The powerhouse is located just to the north of the Villages motel, (also known as Rawanibakoa motel). The Tabwakea power house has two gensets but only one, a Cummins generator manufactured in 1995, appeared to be operational. It has been reported as being 250 kW and 150 kW, but ITP was unable to confirm its rating from the site visit as key parts of the nameplate were no longer legible. Given that it was manufactured nearly 20 years ago, the Tabwakea genset was nearing the end of its useful life.
Figure 20: Tabwakea powerhouse and genset.
4.4.3. Tabwakea load Tabawkea was reported as having a population of 2,311 in the 2010 Census, though it is likely that this figure also includes Tennessee. GIZ reports that the annual consumption is 300 MWh. ITP monitored the load on 24 September 2013, and found that demand varied between 40 and 70 kW. However, GIZ reports that the minimum load can be as low as 25 kW.
4.5. Zone 1 Private generators
4.5.1. Saint Francis School The Saint Francis school is located about 1 km north of the edge of the Tabwakea grid. The genset appears to only be run during school hours.
ITP/A0120 – April 2014 31
Kiritimati Island Electricity Sector
Figure 16: St Francis genset and school
The GIZ LCA report estimates the generator as being 25 kW and servicing a load of 4 to 6 kW, (approximately 30 MWh per year). The low loading on the generator (approximately 15-20%) means that its lifespan will be considerably shortened and that it is operating inefficiently. The main roof areas of the school appear to be suitable for a PV system that would be able to meet the school‟s loads.
4.5.2. Itoin Mainiku School The Itoin Mainiku school (Spivey School) is located about 1 km north of the Saint Francis school. There are two gensets in its powerhouse.
Figure 17: Itoin Mainiku gensets and school
32 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
The white Islington genset has a Perkins engine and is rated as 12 kVA / 9.6 kW. The green Hawkpower genset has a Lister engine and is rated at 22.5 kVA / 18 kW. Both gensets appear to be in poor condition and it was unclear which one was the main operational genset.
The GIZ LCA report estimates the Spivey Secondary School generator as being 25 kW and servicing a load of 3 to 4 kW, (23 MWh per year). Similarly to the Saint Francis School, the generators at Itoin Mainiku are severely underloaded, at 16-40%. The Itoin Mainiku main buildings have several roof areas suitable for PV arrays.
4.5.3. Crystal Beach Motel The Crystal Beach Motel (also known as Fisherman‟s accommodation) is located about 200 m north of the Itoin Mainiku School. It has two gensets in its powerhouse and the owners reported that they will purchase another, larger one when the construction of the new accommodation rooms is completed.
Figure 18: Crystal Beach Motel powerhouse, gensets, battery disposal and new construction.
ITP/A0120 – April 2014 33
Kiritimati Island Electricity Sector
Crystal Beach Motel is at the northern end of Zone 1. An aerial image is shown below, but it appears that several new buildings have been constructed since this image was taken.
Figure 19: Crystal Beach Motel
5. ZONE 2 AND ZONE 3
5.1. Airport / Banana
Banana was reported as having a population of 955 in the 2010 Census. There were 6 commercial, 12 business and 92 residential accounts in 2007.
Figure 20: Airport / Banana powerhouse and gensets
34 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
The Banana powerhouse is close to the Banana water lens. The Banana mini-grid also services the international airport. While the roof areas at the airport have potential for PV, there are long term plans for a major airport building upgrade and this may be a better time for designing long term power solutions for the airport.
In 2007, the metered consumption was 98 MWh per year. Due to the planning uncertainty for Zone 2 given the GoK‟s desire to relocate the Banana residents and the planned airport upgrade, Zone 2 is not analysed in detail in this electricity scoping exercise.
Figure 21: Airport buildings and copra shed.
Near the airport is a large storage shed. There is a large amount of copra being stored here which is likely to have been harvested from the plantations in Zone 2 and to the south. The export point for copra to Tarawa is from the main wharf near Tabwakea. The roof of the copra shed may be suitable for a significant PV array.
5.2. Captain Cook Hotel
The Captain Cook Hotel is the largest accommodation facility on the island and is a Government owned enterprise. It has 52 rooms with 110V power points and each room has a 700 W air- conditioner. The powerhouse had four gensets which were non-operational and power was being provided from a 75 kVA Denyo Sharyo genset on a truck tray near the powerhouse. Although one of the four non-operational generators was being maintained, it is unclear why the other three failed.
ITP/A0120 – April 2014 35
Kiritimati Island Electricity Sector
Figure 22: Captain Cook Hotel entrance, map, powerhouse and genset
During the day, at least 10 external lights were left on and cleaning staff turned room air-conditioners on in the mornings, leaving them to dry empty rooms throughout the day. This may have been due to the desire to keep a minimum load on the 75 kVA genset.
The main compound has roof areas suitable for PV. ITP assessed the suitable roof area facing south-east on the main compound to be approximately 140m x 5m which is sufficient for about 50 kWp of PV. However, incorporating this amount of PV with the existing diesel genset would require a large battery bank.
36 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
Figure 23: Captain Cook Hotel aerial photo
ITP monitored the load for 24 hours and found that during that time the Captain Cook Hotel had a load of 25 to 60 kW (or 900 kWh for the day).
5.3. JMB Store
The JMB complex has two fuel bowsers, a store, freezers, cool rooms and a large workshop. It has a 16 kVA Lister genset that is run continuously and it appears to be in good condition and well maintained. There is also a smaller, mobile genset that is used to directly power appliances such as the welding equipment.
Figure 24: JMB store and genset
ITP/A0120 – April 2014 37
Kiritimati Island Electricity Sector
The owner of the JMB indicated that he had no interest in obtaining power from a Zone 2 mini-grid, if it eventuated. This is because he expected a government run powerhouse would have lower reliability and availability than JMB‟s present power system.
5.4. Zone 3 Poland
Poland is a long distance from both Zone 1 and 2 and was reported as having a population of 441 in the 2010 Census. In 2007, it was reported as having 41 residential accounts with a metered load of 8.7 MWh per year. It is not considered in this report as the EU EDF has announced a 16 kWp PV-battery system for this location.
„As part of the EU EDF10 project, a small diesel grid for Poland village on Kiritimati Island will include 16 kWp of solar with sufficient battery storage to provide much of the village’s energy requirements, leaving the existing diesel to act as a backup.‟, (page 13, Kiribati Pacific Lighthouses, Kiribati Report, IRENA, Aug 2013).
Figure 25: Poland powerhouse, genset and school.
The 60 kW Denyo genset is reported to have been installed in 2005. Both the genset and switchboard are in very poor condition. It normally operates for only 12 hours per day, so electricity consumption is artificially depressed and residents would be expected to increase the amount of electrical appliances they use if a stable supply of electricity were to eventuate.
38 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
6. OPTIONS AND COSTS
6.1. Metering survey and upgrades
Approximately 18% of the electricity that is generated by MLPID is not accounted for in its billing. This could be due to distribution losses, unmetered loads, poor record-keeping, electricity theft, or faulty metering equipment. MLPID should inspect all of its existing meters to ensure that they have not been tampered with and are working properly, and meter all remaining loads. MLPID may nonetheless choose to continue not to bill certain loads (e.g. street lights, some MLPID facilities), but all loads should be metered so that there is transparency in which loads are billed for and which are not. Once all loads are metered MLPID will be in a better position to calculate its distribution losses. Simple mechanical kWh meters are inexpensive, so assuming that 100 buildings/loads need to be metered, the total cost of a metering campaign would be on the order of NZD 10,000.
To improve its revenue collection, MLPID should consider the introduction of a prepayment metering system for its residential and business customers. Under such a system, customers would need to pay for their electricity before they consume it, and recharge the credit on their prepayment meter. Non-payment results in automatic disconnection of the customer by the meter when the meter‟s credit reaches zero. ITP prepared a document on prepayment meters under a previous contract; although it was written for the Tongan context, much of it is applicable to Kiritimati and it is therefore attached to this report.
ITP proposes that the large commercial customers remain on a monthly post-payment metering system (i.e. the one they are currently on), as prepayment is generally impractical for a large business and prepayment meters are not commonly available for large loads. Increasing the tariff for commercial customers to closer to the cost of generation should also be considered, although it is noted that consultations with business indicated that they thought the 33c / kWh commercial tariff was too high and should be reduced.
Smart meters are able to provide a wealth of information on customer consumption habits and can be programmed for time-of-use metering (whereby a utility charges different rates depending on the time of day that electricity is consumed). However, smart meters require communications with the utility office, which adds a level of complexity not present in traditional metering. Currently, smart meters do not have prepayment functionalities (and vice-versa, although some prepayment meters can store information that can be manually downloaded by the utility). Smart meters are unsuitable for Kiritimati at this time given the complexity of the communications requirements, the higher cost of the meters, and the questionable benefit of a smart metering program for MLPID.
ITP/A0120 – April 2014 39
Kiritimati Island Electricity Sector
Fuel and electricity metering should also be installed at all MLPID powerhouses, to properly calculate how much electricity is being generated and how much fuel is consumed for generation. This will help in forecasting load growth and in budgeting for operational expenditures. The expected cost of this is on the order of NZD 10,000, and is likely to be less if new generators are purchased (the control systems in the generators would monitor energy output).
Using the costs associated with the EU-funded prepayment metering system rollout in Nauru in 2008-09, MLPID can expect to pay approximately NZD 600,000 for the supply and installation of 800 prepayment meters (i.e. the existing business and domestic customers, plus 300 new domestic customers). This cost estimate assumes that the installation is done to New Zealand electricity safety standards by an overseas electrical company with assistance from local technicians (as was the case for the Nauru project). Any prepayment meter roll-out will also need to consider any access requirements to meters for recharging the credit, which may have implications for the meter in a locked concrete box approach that is prevalent.
6.2. Capacity building of the utility
GIZ‟s February 2014 report on institutional and capacity building aspects of the MLPID‟s utility division proposes several projects in four key areas:
9. Strategic planning for energy/economic development 10. Reliability of supply 11. Cost effectiveness and efficiency 12. Renewable energy The projects principally include studies and training. Of particular use to MLPID would be a GIS mapping and aboveground marking of all its distribution assets, including training maintenance staff in fault-finding and troubleshooting procedures. This would cost roughly NZD 120,000. Other projects include developing a strategic planning document and energy plan for Kiritimati (estimated at NZD 180,000), energy awareness raising activities, and training of MLPID staff. An energy efficiency campaign is proposed as well; this would greatly benefit MLPID as the more electricity it sells, the worse its financial position (because it sells electricity at a loss).
The estimated total cost of all projects in the GIZ capacity-building report, excluding a prepayment metering project, Zone 1 grid extension and a solar project, is NZD 2 million8.
If all of the GIZ capacity-building projects are implemented, it may be advisable to contract some expatriate technical assistance to manage and assist with implementing the projects. Indicatively, a two-year position would cost roughly NZD 300,000, including mobilization, accommodation, salary, office expenses, etc.
8 Note that as the GIZ report is still in a draft stage and is unreleased the costs in this subsection are subject to change. They have been provided in this report for information only.
40 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
6.3. Interconnect the three Zone 1 MLPID mini-grids
To facilitate any kind of future improvement to the energy sector as a whole on Kiritimati, the London, Tennessee, and Tabwakea mini-grids should be interconnected by an underground 11 kV backbone. If MLPID‟s ultimate goal is to move towards 100% renewable energy, it should connect its disparate mini-grids into one large Zone 1 main grid9. Doing so would be advantageous for several reasons:
Interconnection would allow any future renewable energy generation facilities (e.g. solar or wind) to be located near Tabwakea, where land is more readily available than near London. The lagoon foreshore was identified as a suitable site for a wind turbine by GL Garrad Hassan, and there is ample flat land north of Tabwakea; Having fragmented load centres makes it difficult to properly plan generation investments, as the effect of changing loads (e.g. an increase in the number of residences) is proportionately higher than on a larger grid. A larger grid allows fluctuations in loads and generation (e.g. from renewable energy sources) to be more evenly distributed. Diesel generation assets can be centralized, thereby making asset management easier and more streamlined. Cost savings can be had by reducing spare parts inventory. Grid expansion becomes more practical, as there would be an 11 kV backbone running along the western side of the island that could be used to connect new loads. While interconnecting at a lower voltage is feasible, it may constrain further expansion. This is particularly true if Zone 2 is to be connected within the next few decades. Interconnection of the three mini-grids would incur additional costs beyond just the laying down of a new transmission line. The total load on the new grid would be higher than what could be met by any one of the existing power stations, so some consolidation of existing generation assets in one central location would be necessary (although it is technically possible to interconnect two distant power stations, it would not be cost-effective for such a small grid). The Tennessee generator would not be suitable as it operates at 60 Hz whereas the other generators operate at 50 Hz. Even combining all generators would not provide a sufficient level of reliability, given the dilapidated state of the 250 kW generator at the London power station and the 150 kW generator at the Tabwakea power station.
The London power station would be the simplest choice for the new central Zone 1 station, as it is the largest of the load centres, and has sufficient floor space for additional, or larger, generators. However, it should be noted that the GoK has plans to relocate the London power station to a site just south of the main wharf, between Tennessee and Tabwakea.
9 Note that in some cases it is preferable to have several small mini-grids rather than one large one, as current renewable energy technology is limited in what it can power on a stand-alone basis (the limit is approximately 350-400 MWh/year). As the London mini- grid already exceeds this limit, and the Tabwakea mini-grid will exceed it once the new residential settlements are developed, there are only drawbacks in keeping the two mini-grids separate (e.g. higher vulnerability to large load increases, long distances between land available for renewable energy generation and loads, generation assets spread out). Connecting the Tabwakea mini-grid to the London mini-grid provides an opportunity to connect the Tennessee mini-grid.
ITP/A0120 – April 2014 41
Kiritimati Island Electricity Sector
If the Kiritimati Zone 1 power system is to be refurbished, it may be worthwhile to have generators from the same product line, or at least manufacturer, to reduce the inventory of spare parts required. Replacing MLPID‟s generator fleet would also allow planners to select and size the generators to be suitable for integrating renewable energy generators, such as PV and wind power.
The 11 kV interconnection would run from the northern end of the London mini-grid, at the 4 kV transformer, to the existing Tabwakea and Tennessee power stations. Existing distribution infrastructure is to be maintained to reduce capital costs.
MLPID estimates that this cost would be on the order of NZD 550,000, and would include the purchase of a new generator as the existing 250 kW unit at the London power station is nearing the end of its life. However, ITP estimates that the cost of the cable, its installation (using local labour for trenching), and a new generator would be slightly higher, at around NZD 750,000.
6.4. Build a new Zone 1 power station near the main wharf
This project would require the interconnection of all three MLPID mini-grids. The GoK‟s “Power Centralization Project” includes the eventual construction of a new power station on an area of cleared land south of the main wharf, north of Tennessee. Building the Zone 1 power station in this location would free up some land in London at the site of the existing power station, as well as reduce noise and atmospheric pollution in London. Figure 26 shows the layout and planned usage of the area near the main wharf. Currently, the three identified sites are vacant land, with sparse coconut trees. Note that the fish processing plant is unlikely to be built in the next 3-5 years, and that the plans for the landfill nearby have been cancelled.
42 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
Wharf buildings
Zone 1 power Main road station Fish processing plant
Landfill
Tennessee primary school
Figure 26: Proposed sites (in red) for the Zone 1 power station, fish processing plant, and landfill
Building a new power station would present the perfect opportunity to rationalize the generation fleet of MLPID. The new 400 kW generator at the London power station was manufactured by Cummins; ordering more Cummins generators would be preferable to reusing existing assets (which are in poor condition) or ordering generators from a different manufacturer. The addition of renewable energy sources (PV, wind) would need to be considered when sizing the new generators. Selecting the wrong model or the wrong size may make it more difficult to integrate renewables in the future. The new power station should have roof space suitable for a small PV array, and should have sufficient floor space (or space outside on site) for the eventual addition of battery storage.
The cost of a new power station would likely cost on the order of NZD 2 million to NZD 2.5 million for civil works and generators. For reference, the Japanese-funded power system upgrade on Funafuti cost USD 7.5 million, but included a large power plant, an 11 kV distribution network, and 3 x 600 kVA generators.
6.5. Connect the private grids to the Zone 1 main grid
If the three mini-grids are interconnected, there may be some benefit to extend the Zone 1 grid to the four private grids to the north of Tabwakea. This would provide a higher load for any eventual renewable energy system, and would benefit the two schools and the two hotels by outsourcing power generation to the utility. The existing generators could be kept as backups for the facilities,
ITP/A0120 – April 2014 43
Kiritimati Island Electricity Sector
if the owners wish to do so. Discussions with a Zone 2 private grid operator found that there may be a reluctance to connect to the MLPID grid, as there is the perception that the public grid is not reliable. However, discussions with a Zone 1 private grid operator (the owner of the Crystal Beach Motel) indicated he wanted the grid extension as he will be building more air-conditioned accommodation and is expecting load growth beyond the motel‟s present generation capacity. The poor state of the generators and limited operational hours for the Zone 1 schools indicated that they would also be likely to welcome grid power if it did not increase their costs.
Unless the private grids are charged the true cost of electricity (rather than charged the standard AUD 0.30 or 0.33/kWh) MLPID will end up subsidizing their electricity use. Although this would be beneficial to the schools‟ and the hotels‟ balance sheets, it would put MLPID in a worse financial situation. Tariff reform would be required to offset the additional financial burden on MLPID that would result from the private grids being connected to the Zone 1 grid.
Based on the estimated costs of connecting the three Zone 1 MLPID grids, the cost of connecting the private grids would be approximately NZD 150,000.
6.6. Connect the planned residential expansion in Tabwakea
Connecting the planned residential expansion in Tabwakea would require an upgrade to the Tabwakea power station when the houses are built to accommodate the extra loads. This upgrade would involve the purchasing of new generators. Alternatively, the residential expansion could be interconnected with the other mini-grids (see Section 0), which would be of benefit as it would be more easily absorbed by a large grid (the Zone 1 grid) than by a small one (the Tabwakea grid).
GIZ reports that if people move to Kiritimati from elsewhere to settle, they will do so in areas that are perceived to be desirable (e.g. access to water, electricity, jobs, arable land, etc.), rather than where the GoK plans for them to settle. Haphazard settlement may cause environmental damage in areas with high population density, and has the potential to lead to the development of unplanned settlements where electricity is more readily available. It is of vital importance that the plots of land near Tabwakea that have been allocated to settlement be properly prepared, even if it takes a few years for homes to be built.
Data from GIZ and MLPID indicate that constructing the pillar boxes necessary for the expected residential expansion would be on the order of NZD 825,000. This includes labour and materials.
44 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
6.7. Install a grid-connected PV array
A grid-connected PV system of significant scale (i.e. >100 kWp) would only be sensible if the mini-grids are interconnected, as putting a large PV system on too small a load would lead to voltage and frequency instabilities. If the Zone 1 MLPID mini-grids are interconnected, the noontime load that could be expected is on the order of 200 kW, so the most PV that could be integrated without causing stability would be approximately 60 kWp. A larger system size would require integration equipment (e.g. batteries or sophisticated controllers such as the SMA Fuel Save Controller – although the Fuel Save Controller is suited only for systems 300 kWp and above). Generators should not be kept loaded under 30%, so for the 400 kW generator in London (which would be used when the existing 250 kW generator is being maintained) the maximum PV size that could be connected is 80 kWp. The equipment used for integrating the PV system into the grid would require a communications link with the main power station in London, so locating the array nearby would be advisable.
The two PV capacities calculated above (60 kWp for PV without power stabilizing equipment, and 80 kWp for PV with power stabilizing equipment) are valid for existing energy usage patterns. However, when the residential expansion gets developed the loads will be expected to grow, albeit the growth will mostly occur during the evening peak rather than at midday.
A PV system of this scale would be best located on the ground rather than on roofs, as there would be no issues with access to the panels for maintenance and MLPID would control the site. Having a ground-mounted system would also allow future expansion if sufficient land is secured. If the Zone 1 power station is built south of the existing wharf (see Figure 26), a PV array could be built nearby, at the site previously identified as being suitable for use as a landfill or closer to the power station, or at the site earmarked for a fish processing plant (which could then be built further south). However, if the London power station remains as the central Zone 1 power station, the PV array could nonetheless be built near the wharf but would require connection to the 11 kV network.
A PV system requires very little maintenance other than routine checks and cleaning panels if dirty. The ongoing maintenance costs are expected to be very low over the 25-year life of the system, although inverters will need to be replaced after 10 to 15 years.
The cost of a 60 kWp PV system without any grid stability equipment would be roughly NZD 150,000 installed. An 80 kWp system with integration equipment (e.g. batteries and associated controllers) would cost roughly NZD 275,000, although given that the electricity sector is likely to be in flux soon the size of PV system may increase.
ITP/A0120 – April 2014 45
Kiritimati Island Electricity Sector
6.8. Install a wind turbine
A 200 kW wind turbine could also provide valuable assistance in reducing operating costs at the utility, as shown by the GL Garrad Hassan feasibility study10. The turbine would require connection to an 11 kV network, so grid consolidation must first take place in Zone 1. Several locations in Zone 1 were found to be suitable, although the sound made by the spinning blades may be problematic near residential areas.
The main challenge facing a wind project on Kiritimati, besides the erection of the turbine itself, is the ongoing maintenance of the system. MLPID does not have a good track record for maintenance, as demonstrated by the state of some of its current generation assets, and unless it can secure funding for maintenance (whether from increasing tariffs to reflect the true cost of electricity or from some other source) any wind project implemented on Kiritimati runs the risk of premature failure. Total and irreversible failure of a diesel generator is a relatively inexpensive blunder (approximately NZD 75,000 for a 200 kW generator), but failure of a wind turbine, which GL Garrad Hassan estimated at around NZD 1.25 million, is of much greater consequence. MLPID should have a track record of proper governance and maintenance before embarking on a wind project.
10 Note that the make and model of the turbine used in the analysis is no longer available, and would be extremely challenging to install on Kiribati.
46 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
7. RECOMMENDATIONS AND NEXT STEPS
The energy sector on Kiritimati faces several challenges in the years ahead. If current trends continue, MLPID will be continuously reliant on subsidies to replace its generation and distribution assets, and may even require funding for fuel. There is an obvious need for structural and tariff reform, although the latter may prove to be politically difficult to implement as GIZ‟s consultations with the Kiritimati Urban Council have found that many residents find that electricity prices are unaffordable, despite covering only 50-60% of the cost of generation. Increasing the amount of information that the utility has regarding its own assets and generation is the first step in helping it improve its operations. As such, the metering of generators (both for electricity and fuel use) and GIZ‟s proposed GIS mapping and survey of network assets should be a priority, and should be started soon. A prepayment metering roll-out should also begin as early as possible, although the roll-out would require careful planning (and an awareness campaign) to improve public acceptance of the new meters, so would take more time to complete than the previous two projects.
The three Zone 1 mini-grids should be interconnected to increase reliability of supply for the residents of Kiritimati, as well as allow for future population expansion. Many of the projects discussed in this report rely on the interconnection of the Zone 1 mini-grids, and the advantages of interconnection have been discussed in Section 0. Undertaking this project now is advisable, as with increasing development of the island over the next several years burying the 11 kV cable will become more disruptive and therefore more costly. In parallel with the interconnection, a distribution system should also be installed for the planned residential expansion in Tabwakea, and build a new power station near the main wharf. Any new generators purchased should be sized to be compatible with a large amount of renewable energy penetration. A small (60 kWp) PV system that does not require grid integration equipment should be built near the site of the new power station. Although the PV system would only account for a minimal amount of electricity generation (approximately 5% of total current generation), it would pay for itself quickly (<5 years) and would provide MLPID staff with the experience necessary to manage a larger project in the future.
Other projects that may eventually be considered in the long term are a larger PV array (on the order of a few hundred kWp) with battery storage or a wind project (approximately 200 kW). However, as both projects would be capital intensive and require more maintenance and attention (especially wind) than a small grid-connected PV array, care should be taken before they are implemented. MLPID should prove that it is capable of properly managing its operations and be run efficiently before a large renewable energy project is undertaken. Furthermore, it would be advisable to wait until the reconfiguration of the Kiritimati network (Zone 1 interconnection, new power station, new generator mix) is finalized before putting in large-scale renewables.
ITP/A0120 – April 2014 47
Kiritimati Island Electricity Sector
Eventually, MLPID may wish to connect Zone 1 with Zone 2, once the situation surrounding the moving of people from Banana to New Banana, or the restriction of construction near Banana, is finalized. However, there is no urgent need to interconnect the two zones, although the choice of cable sizing for the 11 kV backbone will be important if a Zone 2 interconnection is foreseen within the next 20 years.
The different projects proposed in Section 6 are summarized in the following table, along with an order of priority and cost for each:
Table 8: Recommended projects, costs, timeframes and priorities
Project Est. cost Timeframe (incl Priority (NZD) tendering, shipping, installation)
Survey and meter all unmetered loads 10,000 6 months Early 2014
Meter generators (fuel and electricity) 10,000 2 months Early 2014
Prepayment metering 600,000 1 year Early 2014
Implement capacity building activities 2,000,000 2.5 years Mid 2014 identified in GIZ capacity-building report
Hire technical assistance to manage all small 300,000 2.5 years Mid 2014 projects in GIZ capacity-building report (and others, if necessary)
Interconnect the Zone 1 mini-grids 750,000 1 year Late 2014
Build a new Zone 1 power station 2,500,000 2 years Late 2014
Connect the planned residential expansion in 825,000 1 year Late 2014 Tabwakea
Install a small grid-connected PV system (60 150,000 9 months Late 2014 kW)
TOTAL for near-term expenditures 7,145,000
Install a larger grid-connected PV system (500 5,000,000 1.5 years 2017+ kWp) with energy storage
Install a wind turbine 1,250,000 1 year 2017+
TOTAL for long-term expenditures 6,250,000
48 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
ITP/A0120 – April 2014 49
Kiritimati Island Electricity Sector
APPENDIX A. GIZ CAPACITY BUILDING REPORT
50 ITP/A0120 – April 2014
Kiritimati Island Electricity Sector
APPENDIX B. BIOFUEL FEASIBILITY STUDY
ITP/A0120 – April 2014 51
Kiritimati Island Electricity Sector
APPENDIX C. TONGA PREPAYMENT METERING STUDY
52 ITP/A0120 – April 2014
Title
2 ITP/A0120 – April 2014