HOMER analysis of the water and renewable energy nexus for water-stressed urban areas in Sub-Saharan Africa

Caterina Brandoni, Branko Bosniakovic

Research output: Contribution to journalArticlepeer-review

34 Citations (Scopus)
147 Downloads (Pure)


Climate change, population growth and rapidly increasing urbanisation severely threaten water quantity and quality in Sub-Saharan Africa. Treating wastewater is necessary to preserve the water bodies; reusing treated wastewater appears a viable option that could help to address future water challenges. In areas already suffering energy poverty, the main barrier to wastewater treatment is the high electricity demand of most facilities. This work aims to assess the benefits of integrating renewable energy technologies to satisfy the energy needs of a wastewater treatment facility based on a conventional activated sludge system, and also considers the case of including a membrane bioreactor so treated wastewater can be reused for irrigation. Using HOMER, a software tool specifically developed for optimal analysis of hybrid micro-generation systems, we identify the optimal combination of renewable energy technologies for these facilities when located in a specific water-stressed area of Sub-Saharan Africa and assess whether the solutions are cost-effective. The analysis shows investment in renewable technologies is cost-effective when the true cost of electricity or average days of power outages per year are considered. Integration of photovoltaic panels, a wind turbine and internal combustion engine fuelled by biogas produced by anaerobic digestion can cover between 33% and 55% of the electricity demand of the basic wastewater facility, at a levelised cost of energy lower than the true cost of electricity. In the case of water reuse, the techno-economically viable solutions identified by HOMER can cover 13% of energy needs. Finally, we discuss how the proposed solutions could provide a large contribution to socio-political security, in both domestic and cross-border contexts.
Original languageEnglish
Pages (from-to)105-118
Number of pages14
JournalJournal of Cleaner Production
Early online date25 Jul 2016
Publication statusE-pub ahead of print - 25 Jul 2016

Bibliographical note

Reference text: Ali SM, Sabae SZ, Fayez M, Monib M, Hegazi NA. The influence of agro-industrial effluents on River Nile pollution. Journal of Advanced Research. 2011 Jan 31;2(1):85-95.
Bekele G, Tadesse G. Feasibility study of small Hydro/PV/Wind hybrid system for off-grid rural electrification in Ethiopia. Applied Energy. 2012 Sep 30;97:5-15.
Bodik, I. and Kubaská, M.I.R.O.S.L.A.V.A., 2013. Energy and sustainability of operation of a wastewater treatment plant. Environment Protection Engineering, 39(2), pp.15-24.
Brandoni, C., Marchetti, B., Ciriachi, G., Polonara, F. and Leporini, M., 2016. The impact of renewable energy systems on local sustainability. International Journal of Productivity and Quality Management, 18(2-3), pp.385-402.
Capra A, Scicolone B. Recycling of poor quality urban wastewater by drip irrigation systems. Journal of Cleaner Production. 2007 Nov 30;15(16):1529-34.
Castellano A, Kendall A, Nikomarov M, Swemmer T. Brighter Africa: The growth potential of the sub-Saharan electricity sector. Johannesberg: Mckinsey and Company. 2015.
Chauhan A, Saini RP. Techno-economic optimization based approach for energy management of a stand-alone integrated renewable energy system for remote areas of India. Energy. 2016 Jan 1;94:138-56.
Chellaney B. Water: Asia's new battleground. Georgetown University Press; 2011.
Chen S, Chen B. Net energy production and emissions mitigation of domestic wastewater treatment system: A comparison of different biogas–sludge use alternatives. Bioresource technology. 2013 Sep 30;144:296-303.
Climate Investment Funds, https://http://www.climateinvestmentfunds.org/cif/node/4. Last access (January, 2016)
Energypedia, 2016. Ethiopia Energy Situation. Available at: https://energypedia.info/wiki/Ethiopia_Energy_Situation Last access (June, 2016)
Escapa A, San-Martín MI, Morán A. Potential use of microbial electrolysis cells in domestic wastewater treatment plants for energy recovery. Frontiers in Energy Research. 2014 Jun 6;2:19.
European Commission. (2013). Future Brief: Bioelectrochemical Systems. Wastewater Treatment, Bioenergy and Valuable Chemicals Delivered by Bacteria. Available at: http://ec.europa.eu/environment/integration/research/newsalert/pdf/FB5.pdf Last access (January 2016)
FAO, AQUASTAT country fact sheet. Ethiopia. 2015. Available at: http://www.fao.org/nr/water/aquastat/data/cf/readPdf.html?f=ETH-CF_eng.pdf Last access (January 2016)
Foster V, Morella E. Ethiopia's infrastructure: a continental perspective. World Bank Policy Research Working Paper Series, Vol. 2011 Mar 1.
Freitas, A., 2013. Water as a stress factor in sub-Saharan Africa. European Union Institute of Security Studies Brief, (12).
Gallagher J, Styles D, McNabola A, Williams AP. Life cycle environmental balance and greenhouse gas mitigation potential of micro-hydropower energy recovery in the water industry. Journal of Cleaner Production. 2015 Jul 15;99:152-9.
Gikas P, Tchobanoglous G. The role of satellite and decentralized strategies in water resources management. Journal of Environmental Management. 2009 Jan 31;90(1):144-52.
Gil-Carrera L, Escapa A, Moreno R, Morán A. Reduced energy consumption during low strength domestic wastewater treatment in a semi-pilot tubular microbial electrolysis cell. Journal of Environmental Management. 2013 Jun 15;122:1-7.
Hao X, Liu R, Huang X. Evaluation of the potential for operating carbon neutral WWTPs in China. Water research. 2015 Dec 15;87:424-31.
Henze M. Wastewater treatment: biological and chemical processes. Springer Science & Business Media; 2002.
Home B, Sale O. The State of the World's Land and Water Resources for Food and Agriculture Managing Systems at Risk. 2011.
Hove M, Ngwerume E, Muchemwa C. The urban crisis in Sub-Saharan Africa: A threat to human security and sustainable development. Stability: International Journal of Security and Development. 2013 Mar 11;2(1).
International Energy Agency. World Energy Outlook 2015 – Energy Access Database,
Available at: http://www.worldenergyoutlook.org/resources/energydevelopment/energyaccessdatabase/
Intergovernmental Panel on Climate Change. Climate Change 2014–Impacts, Adaptation and Vulnerability: Regional Aspects. Cambridge University Press; 2014 Dec 29.
International Bank for Reconstruction and Development, IBRD. Sub-Saharan Africa: From Crisis to Sustainable Growth: a Long-term Perspective Study. World Bank; 1989. Available from: http://www-wds.worldbank.org/servlet/WDSContentServer/IW3P/IB/1999/12/02/000178830_98101901364149/Rendered/PDF/multi0page.pdf Last access (January 2016)
Johnston RM, McCartney M. Inventory of water storage types in the Blue Nile and Volta river basins. IWMI; 2010 Oct 8.
Kebede KY. Viability study of grid-connected solar PV system in Ethiopia. Sustainable Energy Technologies and Assessments. 2015 Jun 30;10:63-70.
Khiewwijit R, Temmink H, Rijnaarts H, Keesman KJ. Energy and nutrient recovery for municipal wastewater treatment: How to design a feasible plant layout?. Environmental Modelling & Software. 2015 Jun 30;68:156-65.. 68: p. 156-165.
Krzeminski P, van der Graaf JH, van Lier JB. Specific energy consumption of membrane bioreactor (MBR) for sewage treatment. Water Science and Technology. 2012 Jan 1;65(2):380.
Lambert T, Gilman P, Lilienthal P. Micropower system modeling with HOMER. Integration of Alternative Sources of Energy. 2006;1(15):379-418.
Lazarova V, Choo KH, Cornel P, editors. Water-energy interactions in water reuse. IWA Publishing; 2012.
Li W, Li L, Qiu G. Energy consumption and economic cost of typical wastewater treatment systems in Shenzhen, China. Journal of Cleaner Production. 2016 Jan 8.
Li, Xin, et al. "Energy-water nexus of wind power in China: the balancing act between CO 2 emissions and water consumption." Energy policy 45 (2012): 440-448.
Libralato G, Ghirardini AV, Avezzù F. To centralise or to decentralise: An overview of the most recent trends in wastewater treatment management. Journal of Environmental Management. 2012 Feb 29;94(1):61-8.
Logan BE. Microbial fuel cells. John Wiley & Sons; 2008 Feb 8.
Maton L, Psarras G, Kasapakis G, Lorenzen JR, Andersen M, Boesen M, Bak SN, Chartzoulakis K, Pedersen SM, Kloppmann W. Assessing the net benefits of using wastewater treated with a membrane bioreactor for irrigating vegetables in Crete. Agricultural Water Management. 2010 Dec 30;98(3):458-64.
Matthew, R., ed. Climate Change, and Conflict. In: Political Demography (J. A. Goldstone, E. P. Kaufmann, M. Duffy Toft, Eds.) p. 133-146. 2012, Oxford University Press. 133-146.
Morris ML. Fertilizer use in African agriculture: Lessons learned and good practice guidelines. World Bank Publications; 2007.
Mo W, Zhang Q. Energy–nutrients–water nexus: integrated resource recovery in municipal wastewater treatment plants. Journal of Environmental Management. 2013 Sep 30;127:255-67
Morera S, Corominas L, Poch M, Aldaya MM, Comas J. Water footprint assessment in wastewater treatment plants. Journal of Cleaner Production. 2016 Jan 20;112:4741-8.
Mushir A, Terfa AB, State of Water Supply and Consumption in Urban Areas at Household Level: A Case Study of East Wollega Zone, Ethiopia. British Journal of Humanities and Social Sciences. 2012 May 5;2:1-15.
Nowak O, Enderle P, Varbanov P. Ways to optimize the energy balance of municipal wastewater systems: lessons learned from Austrian applications. Journal of Cleaner Production. 2015 Feb 1;88:125-31.
Nyenje PM, Foppen JW, Uhlenbrook S, Kulabako R, Muwanga A. Eutrophication and nutrient release in urban areas of sub-Saharan Africa—a review. Science of the Total Environment. 2010 Jan 1;408(3):447-55.
Peterson, P.P. and Fabozzi, F.J., 2002. Capital budgeting: theory and practice (Vol. 10). John Wiley & Sons.
Pan, L., Liu, P., Ma, L. and Li, Z., 2012. A supply chain based assessment of water issues in the coal industry in China. Energy Policy, 48, pp.93-102.
Pfister, S., Saner, D. and Koehler, A., 2011. The environmental relevance of freshwater consumption in global power production. The International Journal of Life Cycle Assessment, 16(6), pp.580-591.
Plappally AK. Energy requirements for water production, treatment, end use, reclamation, and disposal. Renewable and Sustainable Energy Reviews. 2012 Sep 30;16(7):4818-48.
Qasim SR. Wastewater treatment plants: planning, design, and operation. CRC Press; 1998 Oct 5.
Reij CP, Smaling EM. Analyzing successes in agriculture and land management in Sub-Saharan Africa: Is macro-level gloom obscuring positive micro-level change? Land Use Policy. 2008 Jul 31;25(3):410-20
Rockström J, Karlberg L, Wani SP, Barron J, Hatibu N, Oweis T, Bruggeman A, Farahani J, Qiang Z. Managing water in rainfed agriculture—The need for a paradigm shift. Agricultural Water Management. 2010 Apr 30;97(4):543-50.
Satterthwaite D, Urbanization in Sub-Saharan Africa: Trends and Implications for Development und Urban Risk. Urban Transformation. University of Oxford and ESRC (Economic&Social Research Council), December 14, 2015. Available at http://www.urbantransformations.ox.ac.uk/blog/2015/urbanization-in-sub-saharan-africa-trends-and-implications-for-development-and-urban-risk/ Last access (January 2016)
Schäfer M, Gretzschel O, Schmitt TG, Knerr H. Wastewater Treatment Plants as System Service Provider for Renewable Energy Storage and Control Energy in Virtual Power Plants A Potential Analysis. Energy Procedia. 2015 Jun 30;73:87-93.
Scheren PA, Zanting HA, Lemmens AM. Estimation of water pollution sources in Lake Victoria, East Africa: Application and elaboration of the rapid assessment methodology. Journal of Environmental Management. 2000 Apr 30;58(4):235-48.
Shao, L., Wu, Z., Zeng, L., Chen, Z.M., Zhou, Y. and Chen, G.Q., 2013. Embodied energy assessment for ecological wastewater treatment by a constructed wetland. Ecological modelling, 252, pp.63-71.
Shao, L. and Chen, G.Q., 2015. Exergy based renewability assessment: case study to ecological wastewater treatment. Ecological Indicators, 58, pp.392-401.
Shao, L. and Chen, G.Q., 2016. Renewability assessment of a production system: Based on embodied energy as emergy. Renewable and Sustainable Energy Reviews, 57, pp.380-392.
Shoener BD, Bradley IM, Cusick RD, Guest JS. Energy positive domestic wastewater treatment: the roles of anaerobic and phototrophic technologies. Environmental Science: Processes & Impacts. 2014;16(6):1204-22.
Silvestre G, Fernández B, Bonmatí A. Significance of anaerobic digestion as a source of clean energy in wastewater treatment plants. Energy Conversion and Management. 2015 Sep 1;101:255-62.
Skouteris G, Arnot TC, Jraou M, Feki F, Sayadi S. Modeling energy consumption in membrane bioreactors for wastewater treatment in North Africa. Water Environment Research. 2014 Mar 1;86(3):232-44.
Sowers J. Water, Energy and Human Insecurity in the Middle East. Middle East Research and Information Project (MERIP). 2014;44:271.
The World Bank. Carbon finance for sustainable development: 2015 annual report. Available at:
www- wds.worldbank.org/external/default/WDSContentServer/WDSP/IB/2016/04/19/090224b0842a9358/1_0/Rendered/PDF/Carbon0finance0t0annual0report02015.pdf
Theregowda RB, Vidic R, Landis AE, Dzombak DA, Matthews HS. Integrating external costs with life cycle costs of emissions from tertiary treatment of municipal wastewater for reuse in cooling systems. Journal of Cleaner Production. 2016 Jan 20;112:4733-40.
Tiffen M. Transition in sub-Saharan Africa: agriculture, urbanization and income growth. World Development. 2003 Aug 31;31(8):1343-66.
Todaro, M. P., Smith, S. C., Economic Development, Eleventh Edition, p. 317. Addison-Wesley 2012.
UNFPA State of World Population 2007. Unleashing the Potential of Urban Growth. Available at: https://www.unfpa.org/sites/default/files/pub
-pdf/695_filename_sowp2007_eng.pdf Last access (January 2016)
United Nations Development Programme: Human Development Report, 1994.
Available at: http://hdr.undp.org/sites/default/files/reports/255/hdr_1994_en_complete_nostats.pdf
(Last access: June, 2016)
Unicef and World Health Organization, 2015. 2015 Update and MDG Assessment. World Health Organization.
Wang, Y., Chen, R., Chen, T., Lv, H., Zhu, G., Ma, L., Wang, C., Jin, Z. and Liu, J., 2016. Emerging non-lithium ion batteries. Energy Storage Materials, 4, pp.103-129.
Wells EC, Zarger RK, Whiteford LM, Mihelcic JR, Koenig ES, Cairns MR. The impacts of tourism development on perceptions and practices of sustainable wastewater management on the Placencia Peninsula, Belize. Journal of Cleaner Production. 2016 Jan 16;111:430-41.
World Energy Outlook 2016. Available at: http://www.worldenergyoutlook.org/publications/weo-2016/
Wosnie A, Wondie A. Assessment of downstream impact of Bahir Dar tannery effluent on the head of Blue Nile River using macroinvertebrates as bioindicators. International Journal of Biodiversity and Conservation. 2014 Apr 30;6(4):342-50.
Wirkus, L. and Böge, V., 2006. Transboundary water management on Africa’s international rivers and lakes: current state and experiences. Editors, p.11.
Zeyringer M, Pachauri S, Schmid E, Schmidt J, Worrell E, Morawetz UB. Analyzing grid extension and stand-alone photovoltaic systems for the cost-effective electrification of Kenya. Energy for Sustainable Development. 2015 Apr 30;25:75-86.


  • Water energy nexus
  • Renewable technologies
  • Wastewater treatment
  • Sub-Saharan Africa
  • Socio-political security


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