A first-of-its-kind waste-to-energy scheme has been successfully implemented in Addis Ababa, empowering a new era of sustainable waste management for Sub-Saharan African cities.
Image Credit: Belish/Shutterstock.com
Launched by Cambridge Industries, alongside a consortium of international experts in waste management, the plant is set to transform the city’s historic waste crisis into an economy-boosting industry through the conversion of 1400 tons of rubbish per day into renewable electricity. Implementing a process specifically designed for the unique composition of the sub-Saharan waste stream, it is hoped that the facility will act as a feasible blueprint for neighboring countries to follow.
Why is Power Generation and Waste Management a Challenge in Sub-Saharan Africa?
Africa currently has the fastest rate of urbanization of all continents, witnessing a staggering population growth from 27 million in 1950 to 567 million today. With no signs of hindrance, it predicted that the consequential energy demand will rise by 127% in the next 20 years.
However, developments in urban infrastructure have not been able to keep up with such drastic rates of expansion. Power generation and waste management are two of the greatest challenges faced by this rapidly urbanizing continent.
According to the World Bank, 1 in 3 people do not have access to electricity, while municipal solid waste (MSW) collection in Sub-Saharan Africa (SAA) stood at only 44% of all waste generated in 2012. Add to this the low calorific value and high moisture content of this waste stream, and the challenge to implement waste-to-energy solutions, as has been done across many other continents, becomes even greater.
Addis Ababa in particular was victim to a sprawling mass of waste, accumulating in a landfill site the size of 36 football pitches. Leaking toxic substances into nearby rivers and releasing constant plumes of methane gas into the atmosphere, the breaking point came in 2017 when a landslide of rubbish from the site killed 114 people.
The Reppie Waste-to-Energy Solution
In 2018, a novel waste-to-energy power plant rose from this scene of devastation, with the mission to transform the waste crisis into a sustainable source of energy and economy for the area. With a capacity to process 1400 tons of waste per day, the plant, dubbed “Reppie”, generates 185 GWhr of renewable electricity per year; sufficient to supply 25% of the city’s total households.
The seven-hectare facility commenced construction in 2014, with holistic waste management and renewable energy generation company Cambridge Industries Ltd leading the project in partnership with China National Electric Engineering Co (CNEEC) on behalf of its employer Ethiopian Electric Power Company.
Due to the unique consistency of SAA waste, the key to the success of this project was a further collaboration with CNEEC’s affiliate, China Urban Construction Design and Construction Institute Co, Ltd (CUCD). Having determined that China produces a waste stream very similar in composition to that found in Africa, CUCD employed its extensive expertise in the design of a system appropriate to the city’s unique waste requirements.
The general process overview is however similar to the majority of thermal power plants. Once the waste is delivered to the site, it is combusted in a chamber to convert water to steam, which subsequently drives a turbine generator, resulting in the impressive power outputs reported. To comply with the strictest European environmental emissions standards, Reppie has installed a back-end flue gas treatment process preventing almost any production of nitrogen oxides, sulfur dioxide, heavy metals, and dioxins.
This is however not good enough for managing director and co-founder of Cambridge Industries, Samuel Alemayheu.
“We want to create value from everything within the waste stream. The leachate treatment facility treats toxic water from the garbage and converts it into clean water that can be used to water plants or wash the streets. And the super magnets in the ash treatment area sort scrap metal for recycling. The residual bottom ash can be used for construction purposes including brick making,”
Hence, the Reppie plant truly delivers its mission to provide a waste-to-energy solution specific to sub-Saharan Africa, and to transform this waste management into a source of sustainable wealth.
Addis Ababa Reppie Waste-to-Energy Project
Video Credit: Cambridge Industries/YouTube.com
How is this Solution Scalable Across Other Sub-Saharan Cities?
Although the waste-to-energy scheme has been implemented with evident success in Addis Ababa, this is by no means the project complete. Reppie was fostered as part of Ethiopia’s wider strategy, “climate-resilient green economy”, with the objective to boost living standards while reducing its emissions.
To achieve this, the goal has been made to invest $2 billion annually into the expansion of the country’s renewable energy until 2030. This funding is outlined as being sourced from various streams, crucially private investments, climate funds, and through clean energy sales to surrounding countries.
From its initial concept, Reppie was custom-made to the generic waste stream of SAA, and hence, once the identified funding has been secured, the demonstrated technology is ready to be rolled out across other Ethiopian cities. Alemayehu has grander hopes that this will then also inspire other SAA municipals to adopt this circular waste management strategy.
“We believe these plants will create for African megacities a modern, multipurpose infrastructure, using new technology, which will enable them simultaneously to dispose of waste, generate sustainable energy, clean and reuse water, recycle valuable resources, generate industrial grade steam for use by other businesses and, most importantly, do all this in one facility located safely within city limits.”
This could be particularly poignant for Africa’s largest economy Nigeria who, in response to the 2015 Paris agreement, have stated their commitment to tackling the severe levels of greenhouse gas emissions from municipal solid waste.
It is worth discussing however whether this solution is indeed economically feasible for other such cities. Although by law it is the responsibility of Nigerian city councils to implement waste collection services, many of the municipals are bankrupt and simply do not have the resources to build such an infrastructure. Without reliable waste collection as has been achieved in Ethiopia, Alemayehu himself admits that the Reppie structure would prove financially unstable.
He, therefore, highlights that successful implementation depends upon forming key collaborations from the offset to obtain the necessary private sector investments. This has indeed been a fundamental aspect from the initiation of Reppie, and hence there is hope that this approach to financial negotiations within the renewable energy sector can still form an example for other Sub-Sahara African cities to follow.
References and Further Reading
Cambridge Industries. (n.d) Reppie Waste to Energy. [online] Cambridge Industries. Available at: http://cambridge-industries.com/ (Accessed on 2 July 2021)
Cambridge Industries. (n.d) Technical Information. [online] Cambridge Industries. Available at: http://cambridge-industries.com/info (Accessed on 2 July 2021)
Davis, C. (2019) Tipping Point: Turning Africa’s Waste into Energy. [online] FieldFisher. Available at: https://www.fieldfisher.com/en/insights/tipping-point-turning-africa-s-waste-into-energy (Accessed on 2 July 2021)
Gray, A. (2018) This African City is Turning a Mountain of Trash Into Energy. [online] World Economic Forum. Available at: https://www.weforum.org/agenda/2018/05/addis-ababa-reppie-trash-into-energy/ (Accessed on 2 July 2021)
Godfrey, L. et al. (2019). Solid Waste Management in Africa: Governance Failure or Development Opportunity? Regional Development in Africa, Norbert Edomah, IntechOpen. https://www.intechopen.com/books/regional-development-in-africa/solid-waste-management-in-africa-governance-failure-or-development-opportunity-
The World bank. (n.d.) Making Power Affordable for Africa and Viable for its utilities. [online] the World Bank. Available at: https://www.worldbank.org/en/topic/energy/publication/making-power-work-for-africa (Accessed on 2 July 2021)
Thomas, D. (2019). Rethinking Waste: Africa’s Challenges and Opportunities. [online] African Business. Available at: https://african.business/2019/01/economy/rethinking-waste-africas-challenge%ef%bb%bfs-and-opportunities/ (Accessed on 2 July 2021)
Unreasonable Group (n.d.) Meet an Unreasonable Company. [online] Unreasonable Group. Available at: https://unreasonablegroup.com/companies/cambridge-industries (Accessed on 2 July 2021)