Tag Archives: Sub-Saharan Africa

Solar Water Heating as an Energy Service – Part 1 – Technology Choices and Markets

Solar water heaters as a product have the potential to contribute considerably to energy demand reduction in developing countries. This exists both as a household-scale technology, and in industrial applications such as desalination in countries such as the UAE and Saudi Arabia, and industrial process heat in both developed and developing countries. A number of developing countries around the world, notably those in Sub-Saharan Africa, have had success in disseminating solar water heating products on a commercial basis, in addition to a number of large-scale government dissemination programs. Countries such as South Africa (with around 500,000 systems installed as of 2016) and China (which has over 85 million installed SWH units as of 2016) have developed a robust network of commercial installers and manufacturers of solar water heating units and parts, selling products on a market basis to households and businesses.

Solar water heater installed by ESKOM, South Africa. Image: gmourits, Flickr, via http://inhabitat.com/eskom-installs-solar-powered-heaters-on-south-african-roofs/

 

There are a number of opportunities in developing country markets to develop a solar water heating sector. A number of developing countries, particularly those in Sub-Saharan Africa, have high levels of insolation (sunlight kWh/m2/day), and a consistent demand across income segments of the population for water heating. Industrial process heat is another sector where solar water heating could have an impact, as is institutional process heat, for example heat exchangers for hospital refrigeration, and hot water for use in health centres and schools.

Entrepreneurs and companies looking to enter the solar water heating market space need to consider a number of questions before starting their operations. Firstly, an appropriate technology choice is essential for succeeding in the SWH market, perhaps more so than many other renewable energy technologies. Deciding which consumer segment or income bracket to target informs the technology decision somewhat, but thorough research needs to be done on what the market and consumers can afford before deciding on a technology. Main technology streams for SWH include flat-plate solar collectors, and evacuated tube solar collectors. Both work on similar principles, heating water that passes through the collector, either through capillary action or through the use of an electric pump. Flat-plate collectors can be slightly less efficient than evacuated tube designs due to heat loss through convection, however they are also less expensive and simpler to produce. Evacuated tube designs are generally more efficient at heating water, but are also more expensive to compensate for the increased complexity in manufacture.

Flat-plate solar collector installed on a house in the United Kingdom. Image: uk.solarcontact.com

Flat-plate solar collector efficiency vs evacuated tube efficiency at various temperature ranges for a typical North American location. Source: https://blog.heatspring.com/solar-thermal-flat-plate-or-evacuated-tube-collectors/

 

When designing a new solar water heating business or intervention, therefore, it is important to consider which variant on the technology is to be used, and at what scale (household, institutional, industrial etc.), in order to plan dissemination based on affordability for the consumer. The next blog in this series will investigate business and financing models that can assist in improving the sustainability and replicability of solar water heating energy service companies.

– Daniel Kerr, UCL Energy Institute

References

Clean Technica (2015) World’s Largest Solar Powered, Jellyfish-Fightin’ Desalination Plant To Be Built in Saudi Arabia. Available at: https://cleantechnica.com/2015/01/22/worlds-largest-solar-powered-desalination-plant-under-way/

Urban, Geall & Wang (2016) Solar PV and solar water heaters in China: Different pathways to low carbon energy. Renewable and Sustainable Energy Reviews, Vol. 64, pp. 531 – 542

EE Publishers (2016) Solar water heater rollout programme gains momentum. Available at: http://www.ee.co.za/article/solar-water-heater-rollout-programme-gains-momentum.html

Advertisements

Why Isn’t There Greater Adoption of Biogas Technologies in Sub-Saharan Africa?

There are issues surrounding the lack of willingness to finance biodigester projects at all scales in many SSA countries particularly at the household level, lack of financial arrangements for poorer households where technology is most viable, prevailing climatic conditions beneficial but socio-economic conditions (particularly availability of feedstock and financial capacity of rural users) can be problematic.

Household-scale biodigesters can be an effective solution to providing thermal energy services to rural poor communities in the developing world. However, successful examples of biodigester programs in the past at a government or development-agency scale have mostly been confined to China, India and South-East Asia more widely. Notably, there has been a distinct lack of experience of successful biogas projects in Sub-Saharan Africa. The STEPs research project aims to address some of the reasons behind this, and propose potential solutions.

In theory, the prevailing conditions in Sub-Saharan African countries are mostly beneficial for the introduction of biogas digesters. Climatic conditions, on the whole, are suitably warm, with minimal cold periods to impact digester efficiency. In addition, target users are in abundance in rural areas, if considering the local feedstock regime. Small cattle farming is prevalent in a number of SSA countries, and subsistence farmers in rural areas often keep a small head of cattle. Given also the distributed nature of rural populations in a number of SSA countries (particularly, for example, in Eastern South Africa), household-scale biodigesters are an excellent solution for providing thermal energy services to households.

Sovacool Kryman & Smith 2015

Potential uses for biogas and waste products. Sovacool, Kryman & Smith (2015) Scaling and commercializing mobile biogas systems in Kenya: A qualitative pilot study. Renewable Energy, Vol. 75, pp 115-125, http://dx.doi.org/10.1016/j.renene.2014.10.070

However, the lack of successful experience of biogas dissemination programs or businesses can be attributed to a number of factors, first and foremost of which is the cost of biodigesters (ranging from US$30 for a rudimentary drum-type system to over US$700 for a larger household system) [1] [2], and the lack of credit facilities/service regimes to enable access to the technology for the poorest consumers. Biodigester technology still represents a significant upfront cost to a typical rural household, and micro-credit services for clean energy technologies are still in their infancy in SSA countries, with some successful experiences in countries like Kenya or South Africa for solar home lighting or electricity systems in Kenya for example, but little widespread knowledge.

This lack of end-user credit is mirrored in a general lack of energy service companies or institutions offering biodigester services, with the cost issue again a driving factor behind this. Given how critical the maintenance factor is in biodigester installations (an issue which will be explored in the next blog), this lack of service companies, integrating credit or fee-for-service business models with a maintenance and servicing regime, has hampered uptake significantly in the region. The final negative factor is in fact the converse of an advantage: whilst some households will have suitable feedstock availability, compared to average heads of livestock or agricultural waste availability in South-East Asia, SSA has a much lower proportion of households with viable feedstock availabilities. Targeting consumers and areas where feedstock regimes are good is a critical step in ensuring the success of programs or business around biogas digesters in SSA.[2]

The next post in this series will investigate maintenance of biodigesters, and the necessity of maintenance and service arrangements with end-users to ensure efficient and successful operation of biodigesters.

– Xavier Lemaire & Daniel Kerr, UCL Energy Institute

[1] Hojnacki et al, MIT (2011) Biodigester Global Case Studies. Available at: https://colab.mit.edu/sites/default/files/D_Lab_Waste_Biodigester_Case_Studies_Report.pdf

[2] Raha, Mahanta and Clarke (2014) The implementation of decentralised biogas plants in Assam, NE India: The impact and effectiveness of the National Biogas and Manure Management Programme. Energy Policy, Vol. 68, pp. 80-91

What Could the Energy Transition Be for Thermal Energy Services in the Global South

The STEPs project (Sustainable Thermal Energy Service Partnerships) funded by Dfid-DECC-EPSRC is about the design of public private partnerships for the provision of thermal energy services targeting the poorest in developing countries.  The STEPs research focuses on thermal energy services for households and small producers.  The following posts describe what the main needs are in terms of thermal energy services, and with which technologies they could be provided.

Households and small producers in developing countries have needs in terms of cooking, heating/cooling, refrigeration and drying which vary according to the geographical, socio-economic and cultural conditions found in their locations, and can be satisfied in a very different manner than in industrial countries.  Not only can the technologies used be different, but the entrepreneurial model which can help to disseminate these technologies is particular to the Global South: social entrepreneurs, cooperatives, informal groups or established small rural companies acting like utilities have to be involved.

The sustainability of their business models implies the need to find the right mix between different technologies and services provision adapted to the context they evolve in.

Cooking

Currently cooking in developing countries is mainly done using non-efficient cook stoves using traditional biomass (wood, charcoal) or fuels like coal or paraffin. More infrequently efficient cook stoves, bio-digesters or more rarely LPG (Liquefied Petroleum Gas) are used for cooking in rural areas.

Improved cook stoves have been tried to be disseminated for several decades now with mixed results. It seems cook stoves of all kind of shapes and made of all kind of materials have been conceived without being able to reach their intended market. Improved cook stoves fall broadly into two categories – cook stoves that use traditional wood fuels more efficiently, or cook stoves that use improved fuels such as unprocessed charcoal, briquettes or pelletised fuelwood.

600px-GIZ_Diversity_of_improved_cook_stoves_2011

A small selection of the diverse design options for clean cookstoves. Image credit: GIZ 

One of the aims of the STEPs project is to understand if public-private partnerships similar to the ones established for rural electrification could facilitate the dissemination on a very large scale of improved cook stoves. This is done by reviewing the (few) successful experiences of large-scale dissemination of improved cook stoves, for example the National Biogas Cookstoves Program (NBCP) in India (http://www.mnre.gov.in/schemes/decentralized-systems/national-biomass-cookstoves-initiative/), and determining how private business can take charge of the distribution and the marketing of improved cook stoves.

Another way of facilitating the energy transition in terms of cooking facilities is to encourage the use of LPG (Liquefied Petroleum Gas). LPG may not be a very low-carbon energy but it is considered a lot cleaner/less damaging for the environment and efficient than the use of traditional fuels. Unfortunately, the logistics of distribution in remote places makes it unaffordable for the poorest unless a program of subsidies is also implemented, which experiences show are difficult to target. For example, the Ghanaian LPG distribution and promotion program started in the 1990s, and continuing today, has experienced difficulties through cross-subsidising LPG, intended for cooking, through gasoline sales. This led to a rise in LPG transport use and conversions, particularly in urban taxis, skewing sales towards transport use and not rural cooking use as intended by the government program.

Bio-digesters can produce methane for cooking. This technology is widely disseminated in few countries like China or India, but not so much in sub-Saharan African countries. Various reasons have been invoked to explain this situation – low density of population/small size of holdings notably. It seems nevertheless than even if conditions may be less favourable in African countries than Asian countries, there could be specific services organised around collective use of bio-digesters (e.g. cooking in a school by collecting waste from a community).

There are two main approaches to household biodigester construction. The traditional technology is a dome-type biodigester, with the digesting chamber constructed from compacted earth or brick. These are cheap and easy to construct, but are prone to failure and require significant maintenance for good efficiencies. Modern household biodigesters are made from prefabricated plastic digesting chambers, which only require maintenance to maintain the digestion process, and are significantly more durable than the traditional type.

biodigester in cantonment

Biogas construction in cantonment (4971874669)” by SuSanA Secretariat – https://www.flickr.com/photos/gtzecosan/4971874669/. Licensed under CC BY 2.0 via Wikimedia Commons

africa biodigester

Prefabricated biodigester being installed in South Africa. Image: popularmechanics.co.za

agama biogas

Prefabricated biogas digester being constructed by AGAMA Bioenergy worker in South Africa. Image: Agama Biogas PRO via Youtube

Solar cooking and solar ovens are another technology that can be used for cooking in rural areas of developing countries. The Global South, and Sub-Saharan Africa in particular, generally has a good level of insolation for the use of solar technologies. Solar cooking technology however has struggled to find a foothold in Sub-Saharan African markets, and is at a low level of dissemination despite the maturity of the technology. A number of factors could be behind this, most notably the lack of convenience associated with solar cooking and the long cooking times and forward planning associated with using the technology.

ikiwaner solar oven 2008

A solar oven being demonstrated in Ghana. Credit: Ikiwaner / Licensed under CC BY 2.0 by Wikimedia Commons

– Xavier Lemaire & Daniel Kerr – UCL

Indicators of Access to Modern Thermal Energy Services from the Perspective of Households in West Africa

Luc Tossou from Econoler writes on the importance of data collection in assessing clean energy access project performance.

An estimated 2.6 billion people do not have access to clean thermal energy services and rely on solid fuels (wood, charcoal, crop residues and animal dung) to meet their thermal energy needs. Most of these people live in South Asia and Sub-Saharan Africa (SSA). According to a projection by the International Energy Agency (IEA), the situation will worsen in SSA, resulting in a 20% increase by 2030 in a business-as-usual scenario [1]. Several ongoing initiatives have therefore been established to improve access to clean thermal energy services. Clear and relevant indicators must be developed to adequately measure progress in SSA, especially in West Africa with which I am more familiar than the rest of SSA.

Presently in West African countries, quantification of access to clean thermal energy services only focuses on the percentage of households using clean fuels for cooking, such as liquefied petroleum gas (LPG) and biogas. In fact, national surveys and censuses only provide data on types of cooking fuel and disregard conversion technology efficiency (stoves), indoor air pollution levels, along with fuel collection and stove preparation time. Furthermore, national statistics do not provide data on access to clean thermal services such as water and space heating, since these are much less needed than cooking.

In addition to simply representing a measure of access to clean cooking fuels, aspects such as the technical performance of stoves and the time needed for fuel collection and stove preparation must also be considered in determining indicators for projects aiming at promoting access to clean thermal energy services. Integrating all these aspects in such projects is likely to effectively reduce indoor air pollution and alleviate households’ exhausting, lengthy traditional fuel collection and stove preparation effort.

In conclusion, to determine whether or not projects designed to improve access to modern thermal energy services have achieved their goal from the perspective of West African households, key indicators that should be measured include the number of households with access to both clean fuels and efficient stoves, the time spent by households on fuel collection and on stove preparation, as well as indoor air pollution levels. Data on these indicators can be collected by integrating relevant questions in regularly conducted censuses and household surveys.

– Luc Tossou, Econoler

[1] Koffi Ekouevi, 2013, « Scaling Up Clean Cooking Solutions » at http://www.ifc.org/wps/wcm/connect/84f1630042bd9584b2e3be0dc33b630b/Scaling+Up+Clean+Cooking+Solutions+-+Koffi+Ekouevi.pdf?MOD=AJPERES