Africa has an exceptional solar resource that can be harnessed for electricity generation and for thermal applications. The desert regions of North Africa and some parts of Southern and East Africa enjoy particularly long sunny days with a high intensity of radiation. Sahelian and Tropical conditions also feature strong solar irradiation. Solar energy can be utilised at various scales, making it suitable from the household and community levels to industrial and national scale operations.
Power Applications
Two types of technologies exist for power generation: solar photovoltaic (PV) and Concentrated solar power (CSP). The former can be universally used, in applications ranging from household systems to utility-scale, while the latter is typically a technology that performs optimally in utility scale projects situated in the desert regions. Overall, Africa’s solar power generation potential exceeds future demand by orders of magnitude. Even the smallest countries on the continent have at least a few gigawatts of potential for either technology.
Utility Scale – Solar PV and CSP
Distributed Solar PV
Heat Applications
Solar Water Heating – Domestic Applications
Solar Heating and Cooling – Industrial Applications
Water Desalination with Solar PV and Solar CSP
Wind is converted into useful energy utilising wind turbines, for use either to drive electrical generators or to directly power pumps and other machinery. The theoretical potential for wind in Africa exceeds demand by orders of magnitude, and about 15% of the potential is characterised as a high-quality resource. This enormous capacity is not evenly distributed: East, North and Southern Africa have particularly excellent wind resources. Countries with especially high wind quality include all those in North Africa; Niger in West Africa; Chad in Central Africa; Djibouti, Ethiopia, Kenya, Sudan, Somalia, Uganda in East Africa; and in Southern Africa Lesotho, Malawi, South Africa, Tanzania and Zambia.
Power Generation
Morocco has the largest installed wind capacity in Africa. East Africa is also seeing growth, with the 300 MW Turkana project under construction. Additionally, 140 African wind farms are in various stages of preparation, totalling 21 GW of new capacity expected to become operational between 2014 and 2020 (Global Data, 2015). In Egypt, the government’s goal is to have 7 GW of wind power installed by 2020. Morocco has set a target of 2 GW by 2020, and South Africa plans to install 8.4 GW of wind power by 2030 (IRENA, 2015f). The typical range of African wind power projects is smaller than 150 MW. However, projects in the pipeline are increasingly of a larger scale, with projects between 300 MW and 700 MW under consideration. In general, on-shore wind is now one of the lowest-cost sources of electricity available. Costs in Africa are expected to drop further with increased availability of locally manufactured components such as towers and blades.
Hydropower
Africa has abundant hydropower resources. It is estimated that around 92% of technically feasible potential has not yet been developed (IRENA and IEA-ETSAP, 2015b) (Table 2). Central Africa has about 40% of the continent’s hydro resources, followed by East and West Africa, each having about 28% and 23% respectively (Hydropower and Dams, 2014). At the end of 2014 there was 28 GW of hydro capacity installed in Africa (IRENA, 2015b). This makes hydropower by far the most important renewable power- generation option deployed today. Of the resources available, the Congo River has the largest discharge of African rivers, followed by the Zambezi, the Niger and the Nile.
Large-scale hydro resources are often utilised in combination with a storage dam and are suitable for the production of grid electricity. Small hydro plants, (1 MW to 10 MW capacity) may or may not incorporate dams. Mini- (100 kW to 1 MW), micro- (5 – 100 kW) and pico-hydro (less than 5 kW) are suited to run-of-river (no storage dam) installations for the provision of distributed electricity to areas remote from the electricity grid.
Hydropower is dependent on a reliable supply of water, and periods of drought have a detrimental effect on the availability of hydropower stations.
Large-Scale Hydro
Hydropower plant projects with a combined new capacity of 17 GW are currently under construction in Africa (Hydropower and Dams, 2014). Two projects of note are the Grand Inga project and the Great Millennium Renaissance Dam.
The Grand Inga Project on the Congo River envisages the installation of 40 GW of hydro generating capacity, which would make it the largest hydro facility in the world. It is to be developed in 8 phases. The current phase of development, Inga 3, has a total potential of 7.8 GW, and of that total 4.8 GW of capacity is under development. A significant share of electricity is destined for exports, which will go as far as South Africa. Transmission lines totalling 1 850 kilo- meters (km) are to be developed to support Inga 3 exports of electricity.
The Great Millennium Renaissance Dam, situated on the Nile River in Ethiopia is currently under construction and will add a further 6 GW to the grid. Ethiopia has ambitious plans for hydropower expansion including electricity delivery to neighbouring countries.
Hydropower currently offers the most economical solution for large-scale renewable electricity generation, as the technology is mature and the resources are very large in comparison with Africa’s current energy demand. It is less expensive than most technologies of any type for power production. The construction of dams associated with large hydro projects can present some problems.
Small-Scale Hydro
Small hydro is suitable for connection to existing grids or for the provision of electricity in remote areas. Given their smaller size, any dams associated with these plants will have a significantly smaller environmental impact. Africa already has a total capacity of 525 MW from hydro plants with individual capacities of less than 10 MW, with 209 MW in Eastern Africa alone (IRENA, 2015b). Mini- and micro-hydro offer cost-effective solutions to distributed power generation requirements, particularly when the supply is at the village or household level. For these installations, water may be diverted from a rudimentary dam to power a small water turbine.
Where available, the implementation of small hydro plants is a cost-effective off-grid solution for rural areas. Capacity factors are high and generation costs can be relatively low, with an average LCOE (levelised cost of electricity) of about USD 0.05/kWh. The weighted average installation costs for small-scale hydro in Africa is USD 3 800/kW (IRENA, 2015d).
Geothermal
Geothermal energy is a resource of considerable importance in East and Southern Africa. It is estimated that the continent has a potential of 15 GW, all of it found along the Rift Valley, which runs from Mozambique to Djibouti (Geothermal Energy Association, 2015). As of 2014 there was 606 MW of geothermal capacity installed in Africa, of which 579 MW was in Kenya (IRENA, 2015b). Kenya’s capacity more than doubled in 2014, an indication of the rapid rate of implementation of this technology in the country. Kenya has production experience and additional projects with a combined capacity of nearly 3 GW have already been identified. Some are also under development in Ethiopia and Tanzania and aim to increase the generating capacity of these countries by 640 MW by 2018. Djibouti is aiming for projects to come on-stream in 2020.
In December 2014, for the first time, power generation from geothermal sources in Kenya accounted for more than half of Kenya’s electricity output. Kenya is the main hub of the African continent in terms of geothermal technology capacity building and is considering to host the Centre of Excellence for Geothermal Development in Africa.
Geothermal plants are capital intensive and hence development costs have risen along with increasing engineering, procurement and construction costs. Capital costs for recent projects in East Africa have ranged from USD 2 700/kW to USD 7 600/kW, with a weighted average of USD 4 700/kW (IRENA, 2015d). The price tag for projects planned for the period 2015 to 2020 is expected to drop from current levels, but overall these high upfront costs, along with associated uncertainties, are the key barriers to the development of geothermal power plants. In many instances geothermal projects also require long-distance transmission lines. Suitable risk-mitigation and transmission-network development approaches are important for the development of these resources.
Geothermal heat could also be applied directly to industrial processes that require low-temperature heat. These processes dominate a large share of Africa’s manufacturing industry, and geothermal heat is a low-cost and secure substitute for fossil fuels. For example, in Kenya, geothermal direct heat is being successfully used in the flower industry. However, it is more likely that industrial demands will be met by electricity generated from geothermal resources, and then only in East Africa.
Woodfuel
Woodfuel is the single most important primary energy source across the African continent. With almost 15 EJ, it accounted for nearly half of total primary energy supply in 2013 (IEA, 2015). Woodfuel is primarily used for cooking and heating in the residential sector, though sizable amounts are also used by small and medium size industries for metal processing, food processing and brick making. Wood is used either directly as firewood or in the form of charcoal. It is estimated that about one fifth of harvested woodfuel is converted to charcoal.
Continuous trends of deforestation in many African countries over the past two decades, on the one side, and a growing energy demand on the other, point to an unsustainable level of forest harvesting. This is especially evident around densely populated peri-urban and urban areas. Governments are taking initiatives to slow down the speed of deforestation, but considering that 90% of final energy used by households comes from woodfuel, it is clear that a transition to sustainable bioenergy supply requires more effort.
Firewood is often the cheapest option for rural populations to satisfy their basic energy needs and it is also a source of income for those involved in the charcoal supply chain. In urban areas, charcoal is available on the market, and thus more accessible and often more preferred than firewood. Electricity, kerosene and liquefied petroleum gas (LPG) are alternative cooking fuels in these settings. Yet, without subsidies they are often more expensive and therefore not affordable for the urban poor.
In general, woodfuel-based products are commonly produced and used in traditional ways, characterised by low efficiency and adverse impacts on human health and living conditions. It is estimated that nearly 600 000 people died of indoor air pollution in Africa in 2012 (WHO, 2015), and women and children spend a few hours per day collecting firewood, deprived of time otherwise used for more productive activities.
More efficient end-use of traditional biofuels is a key part of the transition towards sustainable bioenergy supply. This should be coupled with sustainable forest management and efficient biofuel conversion technologies.
In addition to sustainable management of natural and planted forest, fast growing woodfuel plantations also provide feed stock for modern bioenergy production. IRENA estimates the wood supply potential from surplus forest (beyond what is needed for non-energy purposes) in Africa at around 1.85 EJ/yr. About 35% of this potential is situated in East Africa and a further 31% in West Africa (IRENA, 2014b). There are already 11 wood based power plants, with a total installed capacity of almost 30 MW, operating in Ghana, Congo, Ethiopia, Tanzania, Namibia and Swaziland, and a number of new plants are planned or under construction (Platts McGraw Hill Financial, 2015). There are also examples of co-firing wood-chips with coal.
Charcoal
Charcoal is a popular fuel because of its high energy content, clean burning characteristics, and easy storage. It is the main fuel of the urban poor and will probably remain so in the forthcoming period during the transition to modern fuels. Even though the use of charcoal seems insignificant compared with the use of firewood (1 EJ compared with 12 EJ in the final consumption), its relative importance has been rising. Over the past 40 years, charcoal annual production has grown at an average annual rate of 6.3% (FAO, 2015). Attempts to impose requirements for sustainable feedstock sourcing, and to formalise and/or control charcoal market have not always been successful. The reasons for that include poor enforcement, complex ownership rights and prevailing socio-economic conditions, in particular given the earning potential that charcoal affords rural households.
Charcoal is currently produced largely in traditional earth kilns with efficiencies of between 10% and 20%, while improved metal, brick and retort kilns offer efficiencies between 25% and 40% (UN-HABITAT, 1993). Even though the investment in higher efficiency kilns would be recovered through increased throughputs, the producers often have limited opportunities to access capital. Accessible funds supported with strong legislative framework on sustainable forest management will be needed to convince the producers of the long-term value to change to more efficient kilns.
Efficient Cooking Stoves
 |
Cooking in Africa is still widely done by placing a pot on top of three stones in a fire, particularly in rural areas. This traditional biomass use, however, is very inefficient and creates health hazards from inhalation of smoke and particulate matter.
Numerous projects have been undertaken to promote the use of efficient cookstoves. Besides the significant efficiency improvement (up to 50% in a modern and efficient cookstove) and the consequent reduction in fuel requirements, the smoke from these stoves can be vented outside, reducing the risk of adverse impacts on health. In addition, the risk of burns associated with open fires can be removed. Countries such as Somalia and Kenya have well-established cookstove programmes, and today similar programmes are implemented in most of Southern, Central and East Africa as well as some in West Africa. The penetration of efficient cookstoves is encouraging, having reached 36% in Kenya and 50% in Rwanda. As carbon-offset projects, 2 million efficient stoves have already been installed in Africa (Global Alliance for Clean Cookstoves, 2014a).
Even though the prices of efficient cookstoves range from USD 5 to USD 10, there is still a barrier to the uptake of efficient stoves in that poor households are the main users of biomass cookstoves and these low prices are still beyond the means of many. Costs can be further reduced by design and manufacture changes, or through subsidies. Alternatively, micro-financing schemes can help those unable to make a large lump sum payment. Some other issues that can result in the failure of cookstove projects include a failure of the stove to meet the cooking requirements for particular dishes, the non-availability of suitable fuels, and religious beliefs in which the traditional cookstove plays an important role in religious lore and practices (Global Alliance for Clean Cookstoves, 2014b)
.
Biomass Residues
Biomass residues are generated at various stages of agricultural and forestry production. They include:
Wood logging residue, i.e. parts of trees that are left in the forest after removal of industrial Roundwood and wood fuel
Crop harvesting residues generated in the fields, such as wheat straw, maize Stover, cassava stalk, etc.
Residues generated on animal farms, which may include manure and a mixture of manure and bedding materials
Agro processing residues generated at the agri-food processing plants, for example rice husk, sugarcane bagasse, etc.
Wood processing residues generated in sawmills, furniture production facilities, or similar, which include bark, sawmill dust, and cuttings
Biodegradable waste, including organic fraction of municipal waste, construction and demolition debris, etc.
The total supply potential of crop harvesting and agro processing residue in Africa is estimated at around 4.2 EJ in 2030. The West Africa region has 40% of this resource. Total supply potential of wood residues (including both logging and processing residue) and wastes and animal residues are estimated at around 1.1 EJ and 1.5 EJ per year, respectively. The North Africa region has 40% of the wood residue and waste resource, and the Central region has the lowest wood residue potential (IRENA, 2014b).
Collection and transportation of residues tend to constitute a significant part of the overall costs. Thus, it is most cost-effective to convert feedstocks into fuels or final energy forms as close as possible to the point of consumption. In the case of waste and residues that may have negative environmental impacts, bioenergy technologies provide a cost-effective solution for their treatment in addition to energy production (IRENA, 2014b).
Crop-Harvesting Residue: Briquettes & Pellets
Crop-harvesting residue can be used as feedstock for briquettes and pellets.
Briquettes have been successfully marketed as an alternative to wood and charcoal in countries such as Egypt, Sudan, Rwanda, Namibia and Kenya. Their greater density means reduced transport costs, a longer burning time and, depending on the type of biomass and processing method, less emissions. However, many briquetting projects have failed in the past due to poor project planning, marketing, low quality products and lack of availability of appropriate stoves. For example, it has been found that in some cases it was essential to locate points of supply and points of sale in proximity to each other, as small-scale producers and buyers may not have access to transport. In the future, creating a briquette industry and market will require addressing these issues and also benefit from creating economies of scale that can reduce prices, for example from the creation of feedstock collection points, where sufficient volume can be collected (ERC, 2012).
Agro and Wood-Processing Reside
Electricity Generation and Industrial Applications
 |
Sugarcane bagasse is widely used to generate the electricity and heat needed on-site. As elsewhere in the world, the African sugar industry has in the past made efforts to adjust the efficiency of combustion to utilise as much as possible bagasse and avoid its disposal. In regions where legal and technical conditions allow, such as Mauritius and South Africa, the industry is also moving toward selling any excess to the grid, which would eliminate the need to adjust combustion efficiency. Bagasse is particularly important in countries that produce large volumes of sugar cane, such as South Africa, Egypt, Sudan, Kenya, Swaziland and Zimbabwe (FAO, 2015).
Besides bagasse, there are several other biomass by-products that are typically generated in Africa which have energy value. For example, wood processing and logging residues in Africa could provide sufficient feedstock for up to 20 GW of power generation capacity (IRENA, 2015a). Generated electricity can be exported, or if dedicated clients are available, the residues could otherwise be processed and sold to them for purposes other than power generation.
In addition to power generation, biomass residues are suitable for a range of industrial applications, providing process heat, as well as heating and cooling of industrial facilities. Food processing is one of the most developed industrial activities in Africa, with typical products including sugar, dairy, baking, beer brewing, fish smoking, tea, coffee, and cocoa, among others. These industries sometimes use traditional methods of production, which are often inefficient. The use of modern renewable energy would modernise processes and provide opportunities to add more value to their products.
Biogas from Residue
 |
Biogas is primarily a mixture of methane and carbon dioxide, produced by the anaerobic digestion of biodegradable organic materials. Various feedstocks can be used for biogas production, including manure, food processing residues, waste water treatment sludge and energy crops. Biogas can be used for cooking and lighting, which is often the case in developing countries with biogas generated in small sized digesters, as well as for power and heat generation in industry facilities and on commercial animal farms.
Landfill gas is another gaseous fuel generated from the organic fraction of municipal waste. Landfill gas projects are becoming increasingly common in Africa. For example, in South Africa, the Durban municipality has implemented a land- fill gas-to-electricity project with an installed power generation capacity of 7.5 MW (IEA, 2014b).
A number of interesting biogas-generation projects have been initiated in Kenya, such as producing off-grid electricity from biogas generated by manure and sisal, utilising slaughterhouse waste to produce biogas for electricity production, and another producing 20 kW of electricity from vegetable waste (IRENA, unpublished).
Biogas is commonly used in rural areas of China and India, mainly for cooking. The estimated potential for biogas in Africa is significant, with 18.5 million households having sufficient dung and water, primarily in rural areas. A number of programmes are in place in Africa to increase the use of biogas in domestic applications. The Africa Biogas Partnership programme has already installed 46 000 digesters (Africa Biogas Partnership Programme, 2015) and intends to extend the programme to reach another 100 000 households by 2017, in Kenya, Ethiopia, Tanzania, Uganda and Burkina Faso (Africa Biogas Partnership Programme, 2014). Cameroon and Rwanda have initiated national programmes for the implementation of biogas.
Biogas digesters are typically designed to serve more than a single household and are thus a solution for urban peripheral and rural communities. However, costs are high, and subsidies are typically applied to encourage their use. In Kenya, for example, a EUR 240 per plant flat subsidy is provided, while in Cameroon 30% of the digester cost is subsidised. Without subsidies or innovative financing methods the availability of biogas facilities to the poor will be limited.
In industrial settings, dairy operations and other food-processing plants, technically all energy requirements could be met by converting manure to biogas. Several pilot and demonstration projects have been put in place in various African countries.
Energy Crops
Energy Crops for Liquid Biofuels
 |
The feedstock used for production of first generation liquid biofuels includes starch and sugar crops in the case of ethanol and oil crops in the case of biodiesel. The most common crops used for the production of liquid biofuels in Africa are sugarcane and molasses for ethanol, and oil palm, jatropha and to some degree soybean and sunflower for the production of straight vegetable oil and biodiesel. Advanced technologies also allow for production of ethanol and biodiesel from woody (lignocellulosic) biomass. Liquid biofuels can be used in the transport sector, pure or blended with fossil fuels, as well as in the industry, agriculture and residential sectors as engine, cooking or lighting fuels.
In many African countries there is a significant gap between the current and potentially attainable crop yields. Through sustainably improved productivity of agricultural production, sufficient crops would be produced to ensure food security while providing feedstock for production of liquid biofuels. Due to the lack of verifiable information and data on the current land use, agriculture production practices and foreseen food and feed needs, estimates for energy crops potential for the whole continent are highly uncertain, ranging from 0 PJ yearly to 13.9 EJ/yr., depending on assumptions (IRENA, 2014b). Southern and East Africa show the most promise for ethanol production, and Southern Africa has by far the greatest potential for plant oil crops.
IRENA estimates that the energy content of that potentially available for conversion into liquid biofuel by 2030 at about 4.8 EJ/yr. 3.6 EJ of this potential corresponds to crop for ethanol production. 65% of ethanol potential is found in Southern Africa and 20% is in East Africa, followed by Central Africa. West and North Africa contribute a negligible amount (IRENA, 2014b). Oil palm, the fruits of which are important feedstock for biodiesel, is produced widely in plantations in West and Central Africa and particularly in Nigeria, Ghana and Benin. For biodiesel, 41% of potential is found in Southern Africa and 22% each in Central and Eastern Africa, while West Africa accounts for 15% of the potential.
The total installed costs for biodiesel plants are generally lower than those associated with ethanol production. A study of North African and Middle East countries found the installed costs to be USD 0.25/litre/year of production capacity (IRENA, 2013b).