GENERATION The potential contribution of in by Douglas Banks, RAPS Consulting, and Jason Schäffler, Nano Energy

This article is the executive summary of a project report commissioned by the Sustainable Energy and Climate Change Project (SECCP), a project of EarthLife Africa . The full final report may be downloaded from the EE - Downloads resource at www.eepublishers.co.za/view.php?sid=1392, at the EE Publishers website, www.eepublishers.co.za

South Africa has an energy-intensive weather experiences (e.g. economy, currently using more than storms, droughts, melting 4000 PJ per annum. The polar ice-caps). Local air economy relies on low-cost electricity and pollution is strongly related coal to power energy-hungry industries such to energy supply options, as mining and metals processing. Although with coal and oil products growth in energy consumption has, for the being major contributors to last two decades, been slower than was urban and rural air pollution anticipated in the late 1970s, more recent and acid rain. economic growth and improved distribution Renewable energy options of electricity to households have resulted in are a sustainable energy significant increases in electricity demand. supply option that can The country also relies on coal and liquid significantly reduce fuels for chemical processing, heating, reliance on fossil fuels. transport and other activities. The renewable Other advantages include contribution to energy supply is relatively Fig. 1: Business as usual - energy demand matching (Note 1) employment creation, limited, with biomass being estimated to proximity to point-of- contribute 9 to 14% of energy needs and energy efficiency and a shift away from use and, in many cases, less reliance on hydropower about 1%. an energy-intensive economy (gradual concentrated sources of energy (and political decoupling of economic growth from energy This report explores future energy scenarios power). Greater use of renewable energy demand growth), could reduce the rate (up to 2050), and attempts to understand would also reduce South Africa’s economic of increase in energy demand. We have the implications of growing power demand, vulnerability to the variable (and escalating) therefore used a total energy demand of changing technologies and an evolving costs of imported fuels. International and 6700 PJ by 2050 against which to explore energy environment. The focus is on the local communities are increasingly trying the potential contribution of renewable potential contribution of renewable energy to find ways to shift economies towards energy. Electrical energy demand comprises and the path to achieve a more sustainable greater reliance on renewable energy. We 1279 PJ (366 TWh) of the total energy . The scenarios look far into the anticipate that policy and regulation, as well demand. The final scenario presented in the future, and the work has been undertaken as voluntary schemes such as the ‘Clean report uses the same 6700 PJ total energy with limited resources. The specific choices Development Mechanism’ and Renewable demand, but allocates a higher proportion of and projections made can certainly be Energy Certificates will provide increased total demand to electricity (600 TWh). questioned, and some will probably be support for an expanded role of renewable proven incorrect. However, the trends and Why renewable energy? energy in the economy. core elements are in line with international Growth in demand is not the only reason to work, and we consider them to be highly Renewable energy potential in South consider alternative energy supply options. plausible. The document’s purpose is to Africa Firstly, current energy supply in South Africa stimulate thought and debate, and in doing is primarily coal-based and, although these Several renewable resources have the so, help us prepare for the uncertain future. resources will last for more than a century potential to contribute significantly to South Demand scenario if used at current rates, large power plants African energy supplies. In particular: will need to be replaced over the next 30 In the next 50 years, as economic development  Solar thermal (for heating), solar years. Secondly, coal has many other uses, takes place, energy demand is expected thermal electricity generation and solar and we need to conserve this resource to grow significantly, driven particularly by photovoltaic electricity generation. South for future use. Thirdly, coal and other fossil important changes in livelihood patterns of Africa has an excellent solar resource. fuels, including oil, produce Carbon dioxide the millions of people who live at or below  Wind electricity generation. South Africa when burned to produce energy. It is now the poverty line. There is a projected tripling has fair to reasonable wind resources by widely accepted that climate change, of total energy and electricity requirements if international standards. partially caused by human-generated current government planning projections (up carbon dioxide, represents an extremely  Biomass (heating, cooking, electricity to 2022) are extended to 2050. serious environmental threat to the world as and, in particular, liquid fuels for transport However the population growth rate is a whole. Human-induced climate change and cleaner cook stoves). Biomass expected to reduce during the next 50 years. is already being blamed for the higher-than already contributes between 9 and 14% This, coupled with a greater awareness of usual incidence of extremely damaging to the total energy requirement, but it

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Resource/technology potential Solar thermal electric contributions Solar thermal electric technologies use the Solar photovoltaic sun’s heat to drive either conventional steam turbine drive power plants, or to power more Photovoltaic modules are unusual engines such as the Stirling engine. already widely used in South In the medium term, these are expected Africa, serving perhaps 200 000 to be cheaper than photovoltaics, but this households (e.g. lighting, television, comparison is uncertain 40 years into the telecommunications) along side future. However, solar thermal electrics have several thousand rural institutions an advantage in that single plants can and water pumps. At present, be built on a multi-megawatt to gigawatt the solar modules are expensive, scale. There is also some potential for energy although their cost has been steadily storage in thermal energy stores (e.g. molten Fig. 2: Progressive Renewable Scenario: Illustration of how declining. In the scenarios described, salt). This allows some solar thermal plants to electricity energy demand would be met (Note 2) we envisage PV technology playing run well into the evening, or even 24 hours could be utilised more efficiently, and an extremely important role (up to a day. Gas hybridisation options are also current use is not always sustainable. 14%) in electricity supply by 2050. practical. Solar thermal electricity generation

 Hydropower. South Africa is not particularly The major drawback for solar generated is thus likely to play a larger role than PV in the well endowed with hydropower potential, electricity is that it is difficult to store. For off- medium term. but there is potential to import hydropower grid systems, current storage technologies Solar thermal heating and to develop locally significant micro- require significant running costs (due to their hydro potential. limited life). However, new technologies Solar water heaters, process heaters, space heating systems and even solar cookers are  Wave power. This is a new technology, such as super capacitors, flywheels and all currently used in South Africa. The water but one from which South Africa could fuel cells, as well as improved chemical heater market in particular shows significant benefit, as there is an extensive coast-line batteries, are expected to reduce storage signs of maturity and growth potential. with high wave energy potential. Ocean costs significantly. Currently grid connected However, as a country, South Africa is behind currents, thermal gradients in the sea, applications are the main international best practice norms with regards to utilising and even ocean grown biomass could market for PV technology. In this case, the this resource. Neighbouring Botswana is far also play a future role. ‘grid system’ can be used as storage along ahead and countries such as Israel use solar with distributed storage options and pumped  Other resources, such as geothermal, energy to heat 60% of their water. A recent storage systems. may play a lesser role. study indicates that up to 43 TWh of electricity

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Fig. 4: Progressive renewable scenario: Illustration of final energy supply (in PJ), by resource. Fig. 3: Progressive Renewable Scenario: Illustration of the possible changes in cost per unit energy over time (Note 3) could be displaced by solar resources by hydro capacity over and above existing 2040. If the gas were to be used for process 2030. national and imported capacity. Imported heat, then the energy extraction would be hydropower could add a further 7000 MW – or higher. Wind energy even more, but there are concerns regarding Wave energy Wind energy conversion systems currently supply security and political stability. convert the energy in moving air to electricity. The ocean breakers crashing onto our Biomass energy In the longer term, this energy could be shores have an average energy intensity converted to even more versatile energy Biomass energy is currently the largest of approximately 25 MW/km over about carriers such as hydrogen. Wind prospecting renewable energy contributor in South Africa, 900 km of coastline. If 75% of this coastline is in its infancy in South Africa and descriptions estimated at about 9% (some data indicates were suitable for converter installation, of this resource vary from ‘abundant’, through as high as 14%). Most rural households and then a total generating capacity of about ‘significant by international standards upon several hundred thousand low-income 18 000 MW could be installed. Eberhard which wind industries have been built’, urban households rely on fuelwood for and Williams (1998) estimated that a more to merely ‘modest’. This study, pursuing cooking and space heating. Biomass by- conservative annual average of 8000 MW a progressive yet plausible transition to a products are used in boilers by the sugar could be generated, with a winter average sustainable energy future, has included an and paper industries to generate electricity. of 10 000 MW. This could yield up to 70 TWh annual contribution of 66 TWh and 80 TWh The South African government and other per year. large stakeholders (e.g. Sasol) are currently for the two renewable energy scenarios Wave technology is receiving increased developing the capacity to produce liquid presented. international and national attention and has fuels from biomass, with an estimated better base load characteristics than many Focussed along the extensive coastline and potential of 20% of the national liquid fuels other renewable energy technologies. the lowland/highveld escarpment, wind requirement (45,7 PJ). The production of bio- energy is a potentially abundant resource ethanol, for possible use as a safer household Other forms of renewable energy which could be readily extracted and fuel, is also receiving increased attention. converted to useful energy using off-the- In the longer term, we anticipate biomass A number of other possible renewable energy shelf technology. As with other technologies contributing between 9 and 16% of the options can be considered. Geothermal seeking to harvest distributed resources energy requirement. energy, located in the Western Cape, sustainably, wind energy systems promise may be able to contribute about 500 MW, Extensive use of biomass raises significant significant benefit in terms of building and ocean currents, such as the Augulus environmental concerns. The large-scale increasingly flexible, robust, secure, stable stream, could also be exploited to generate use of bioenergy would require vast areas and cost-effective energy supply systems. electricity. These options have been grouped of land to be converted to ‘energy crops’. together in the scenario analysis in a ‘Wave Hydro-power In the first of the two renewable energy and Other’ category. They are assumed to scenarios described we have limited the area Water scarcity concerns are often used start coming on stream only after 2015, and allocated to new energy crop production (for to dismiss out-of-hand the potential for by 2050, are assumed to yield 33 TWh per electricity generation) to be of the same order hydropower in South Africa. In reality, energy year (medium renewables scenario) – or in of magnitude as existing sugar plantations. derived from extracting the potential energy the case of the high renewable scenario The high renewable scenario uses higher of elevated water during its descent has 69 TWh/year. figures, which would need better verification an important role to play. This is especially in terms of environmental impact. Storage, distributed generation and energy important when one considers the huge efficiency volumes of water that are moved around the Landfill gas country in balancing the supply and demand Energy storage is a critical element of energy Landfill sites generate methane gas as a for water, and the fact that the energy content planning, both for the electricity sector and for result of the decomposition of the biomass of this water is seldom considered. other energy options. Storing electricity in large components in municipal waste. Landfill quantities poses many difficulties. Electricity This study has considered the role of gas has a potential for 7,2 TWh of electricity storage is especially critical in renewable approximately 4700 MW of domestic installed generation, perhaps growing to 10,8 TWh by energy systems due to the intermittent nature

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Fig. 5: Progressive renewable scenario: percentage renewable contribution to total final energy demand and to electricity supply Fig. 6: High renewable scenario: Total energy supply mix (Note 4) of many renewable energy sources and the renewable energy contribution in this scenario a large-scale, economically viable power variability in electricity load requirements. This reaches a maximum of 4%. supply option. combination of problems represents one of Fig. 2 illustrates a ‘progressive renewable’ Electricity is of course only one part of the the most important challenges facing the future in which renewable energy plays total energy requirement. The contribution widespread (small and large-scale use of a moderate role in electricity generation of different resources to total final energy renewable energy. by 2020 (about 13,3% contribution) and demand in the ‘Progressive Renewable’ The scenarios in this study use pumped contributes about 70% by 2050. The pre- scenario is illustrated in Fig. 4. Four main storage as the main storage technology. 2020 installations would place the country renewable energy components are shown, together accounting for 35% of final energy Existing capacity is approximately 1,5 GW in a strong position to expand capacity consumption by 2050: and there is potential for 7 to 10,3 GW of rapidly from 2022 onwards, as coal plants are decommissioned. Such preparatory new capacity, increasing total potential  Biomass is expected to continue to play work would be important for local capacity storage to 11,8 GW by 2050. A key limiting an important role as a direct source of development and job creation. However, it factor for pumped storage technology is its energy, although the continued growth may also be critical to secure the potentially environmental impact. Meanwhile, other indicated in the graph is possibly not realisable cost reductions in renewable technologies are being developed, including sustainable with respect to environment energy technology. and food security. redox batteries, flywheels, super capacitors, super conductors, and compressed air Both the above scenarios illustrate how short  Solar water heaters are shown to contribute approximately 150 PJ per annum by options. It is our opinion that adequate time really is, particularly in the light of the 2030. This would entail significant growth capacity will exist to be able to put the required growth rates for emerging industries of the solar water and process heat necessary storage in place as required. There such as solar PV, wind and solar thermal market. will, however, be a cost penalty. electricity. Effective large-scale industries will  Biofuels (biodiesel, ethanol and other take time to develop and, even at a 20% As the electricity supply sector evolves, options) are shown as an additional annualgrowth rates for emerging industries there is likely to be greater use of distributed biomass contribution, also contributing such as solar PV, wind and solar thermal generation, and many of the renewable about 150 PJ by 2030. Note that this electricity. Effective large-scale industries will energy technologies lend themselves would have significant environmental take time to develop and, even at a 20% impacts. At a production rate of particularly well to distributed generation annual growth rate, it will take several years 120 GJ/ha, this would require a land area applications. This can help to reduce before they can start to add energy capacity of 12 500 km2. This is about 1% of the transmission and substation investments to the grid on the scale required. South African total land area, and about and can, to some extent, mitigate the as large as current forestry plantations. requirement for storage. Lower cost options, such as biomass, landfill  The renewable energy component of gas and selected wind sites, are initially electricity supply is illustrated. Scenarios for future energy supply more attractive than solar and large-scale These scenarios and the resource assessment Three scenarios were reviewed for electricity wind. However, these low-cost options have indicate that there are sufficient renewable generation: business as usual, progressive a limited resource base and it becomes energy resources in South Africa to provide renewable, and a high renewable scenario. important to balance development effort about 15% of the electrical demand by The ‘business as usual’ scenario (Fig. 1) - harvesting the lowest cost resources but, at 2020, and easily 70% or more by 2050. From assumes very little support from decision- the same time, developing the necessary a total energy perspective, the medium term makers for renewable generation technology. technical capacity to harness the larger-scale contribution of 15 to 20% is quite feasible. The scenario clearly illustrates the huge solar and possible wave technologies. However in the longer term, it will be difficult increase in capacity of fossil plants that Although speculative, Fig. 3 highlights, to achieve more than a 35% contribution would be needed between 2022 and somewhat surprisingly, that renewable energy by 2050 using the options discussed above. 2038. This raises major environmental and options are likely to be the most cost-effective Indeed, it should be noted that the total economic warning flags. It also highlights options for energy supply in the future. Fossil consumption of fossil fuels increases from the opportunity that we have as a country fuel pricing is particularly difficult to predict 2005 to 2050 in the ‘Progressive Renewable’ to prepare for the capacity crunch, and (e.g. oil price in 2004/5), but if prices do scenario, with obvious concerning implications to have alternative solutions in place for continue to rise, it will not be long before solar for climate change, fossil resources and the implementation on a large scale. The thermal technologies in particular present environment. Note: the total energy scenario

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illustrations shown indicate that biomass currently Fig. 6 shows this high renewable scenario. It contribution, without stretching the renewable contributes about 14% to final energy demand. should be noted that total electricity demand energy resources and technology production If the biomass contribution is closer to the has risen significantly (to 600 TWh, or 2108 PJ), facilities as much as indicated in the progressive and direct use of Hydrogen or other renewably renewable scenario. 9% indicated by some data, then the renewable produced energy carriers contributes energy contribution to total energy will have to Notes 1400 PJ to the total energy demand by 2050. be reduced by about 5%. With these (or similar measures) it will be noted 1. Supply is shown as being higher than demand because of the need to provide that the percentage contribution of renewable A third scenario called the ‘High Renewable’ extra or reserve capacity to deal with energy to the total scenario was then developed. This scenario peak demand periods or generation plant looks at the options to achieve a net reduction final energy demand rises to 60% by 2050. shutdowns for maintenance. In practice in fossil fuel consumption by 2050, and could Furthermore, there is a net reduction in fossil some of the generation equipment would be considered as a ‘climate change’ driven fuel contributions, thereby allowing South Africa be turned off or run at reduced output so scenario. It differs in two primary ways from the that supply matched demand. to reduce its CO2 emissions in line with the ‘Progressive Renewable’ scenario: requirements for developed countries set out 2. For colour version of this figure see Fig. 5-4 on page 42 of the full report.  it is assumed that a large proportion of the in the Kyoto Protocol. current non-electrical energy demand 3. For colour version see Fig. 5-6 on page 43 The authors regard achieving the progressive of the full report. in South Africa (e.g. transport, coal or oil renewable scenario to be extremely based process energy supply in industry) 4. For colour version see Fig. 5-11 on page challenging. For South Africa to make the 50 of the full report. can be met by electricity (produced using necessary shifts in the energy economy to 5. This is an average annual increase of only renewable resources) achieve something like the high renewable 1,5% over the 50 year period. Current  it is assumed that hydrogen can be scenario would be significantly more difficult. National Integrated Energy Planning generated from renewable resources However, if the total energy requirement of processes have energy demand growth on a large scale. This can be stored and the country is allowed to increase to 6600 PJ rates in excess of 2,8% for some sectors transported and used as required, much (Note 5) over the next 50 years then investments – see Fig. 2-3. like coal, oil and natural gas – thereby in energy supply will in any event be very 6. This article is an executive summary. replacing a significant part of the remaining large. If it is possible to develop the economy The full report may be downloaded non-electrical demand. using approaches that do not require such an from the EE-Downloads resource at The total energy demand has not been increase in energy consumption, and if energy http://www.eepublishers.co.za/view. reduced, thus leaving a similar allowance efficiency can be effectively promoted at all php?sid=1392 at the EE Publishers for economic growth to that given in the levels- then the average annual growth in website www.epublishers.co.za energy demand could be reduced, or even business as usual and progressive renewable pushed into the negative. This would obviously Contact Richard Wortiughton, Earthlife scenarios. make it far easier to reduce the total fossil fuel Africa, [email protected]

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