Energizing Waste

By+Kiram+Tadesse

The 36-hectare Reppie Sanitary Landfill， also known as Qoshe， dirt in local slang， has been Ethiopias biggest rubbish site for more than half a century. The landfill， located on the outskirts of Addis Ababa， Ethiopias capital， has through the passage of time become surrounded by emerging city suburbs. It is however now being put to much better use in the form of Africas first garbage power plant， providing the city with a new concept of clean energy.

The Ethiopian Government decided to introduce the waste-to-energy （WtE） concept to the country at a cost of $100 million in recognition of the technologys widespread and increasing use in Europe， the United States and Asia to produce clean renewable energy. In so doing， it will convert a major burden， which is waste， into a much needed resource， energy.

To realize the new concept， the Ethiopian Electric Power （EEP）， a government corporation engaged in the production， transmission， distribution and sale of electrical energy， brought a consortium led by both China National Electric Engineering Co. Ltd. （CNEEC）， a company with a long record of executing terminal projects all over the world， and Cambridge Industries， an African-focused renewable energy developer， plus a group of investors who have years of experience in emerging markets in Sub-Saharan Africa.

Niklas Helsen， Project Site Engineer， told ChinAfrica that Reppie will be a milestone in Africas drive toward sustainability， especially in the field of waste management.

He said while it is not the only project in Africa that produces renewable energy， as there are also multiple solar， wind and hydropower projects， Reppies main environmental benefit is in its waste management concept.

“The alternative today is to pile up post recycle municipal waste， which is the situation in every major city in Africa， and this is one of the most exciting environmental projects in the world today，” said Helsen.

EEP has long sought to shift the balance of power generation in Ethiopia toward a reliance on renewable energy， as demonstrated in the countrys existing hydro and wind facilities.

Wondimu Tenkir， Deputy Project Manager， said the facility started construction at the end of 2014 and currently has completed over 90 percent of the project.

“When completed， the Reppie WtE facility will process 1，400 tons of municipal waste every day and has capacity to produce 185 million kwh of electricity a year，” he added.

Clean energy source

According to Ethiopias Ministry of Environment， Forest and Climate Change， the introduction of Reppie WtE project facility is a way to promote the countrys green economic strategy， as well as to manage pollution.

Debasu Bayleyegn， Director General for Climate Change Implementation Coordination at the ministry， told ChinAfrica that the project starts from waste management and hence it will have significant implications with regard to reducing pollution.

Bayleyegn said the facility helps produce energy that will meet one third of the energy demand in Addis Ababa.

“It will further create green jobs for employees who work with the facility，” he added.

Helsen stressed that the project has strict environmental standards that are followed in the facility and the extensive flue-gas cleaning system meets European emission standards.

In every uncontrolled dumping site， there is a local environmental catastrophe， with leaching going straight to the groundwater and the danger of a constant fire hazard because of the methane gas. Smoke that comes from uncontrolled landfill is also extremely toxic， Helsen explained.

Reppie is in the middle of the city and that makes it very dangerous， he added.

He said massive amounts of methane gas are produced in the landfill. About 1 molecule of methane gas is around 25-times as harmful to the climate compared to carbon dioxide. Every molecule of methane gas that goes out from the landfill is extremely harmful to the environment.

Economic benefits

Apart from the clean renewable energy generation， the facility can produce over 3 million bricks from the bottom ash every year. That by itself will create jobs for local people， said Ermias Alemayehu， Head of Human Resources at Cambridge Industries.

Furthermore， the facility is expected to treat more than 30 million liters of water a year from the leaching that pollutes groundwater. The treated water will have drinkable quality and the Addis Ababa City Administration is looking to use it for irrigation purposes. The landfill can also produce 2 million tons of steam， said Alemayehu， adding that the steam can be used for curing concrete along with other manufacturing uses.

The facility also has a unique way of collecting metals with a super magnet from the bottom ash to separate all the metals that comes out to the facility， and it is expected to separate more than 3.6 million kg of metal each year.

Unique project

It was clear from the outset that Reppie was going to be a unique facility， says the consortium of the project， not just because of its location at an altitude of 2，300 meters above sea level， a level at which few WtE facilities of its size have ever been built， but more importantly because of the lower heat value and higher moisture content found in the waste stream.

The facility was designed by a firm with extensive experience in constructing facilities with similar waste conditions to Addis Ababa. The consortium also engaged CNEECs affiliate， China Urban Construction Design and Research Institute （CUCD）. CUCD， Chinas vastly experienced national design institute， has been responsible for designing dozens of such facilities across China， a country with a waste stream composition that is very similar to that found in Africa.

Insiders believe that the Reppie project is an important diversification of EPPs renewable energy sources in Ethiopia. Ethiopia also realized that the technology is even more applicable to Africa where its rapid urbanization and economic growth are creating ever larger volumes of daily municipal waste， which its waste collection and disposal systems struggle to process.

Once operational， Reppie will be the first major WtE facility in Africa. The facility is expected to eliminate over 80 percent of the municipal solid waste delivered to the dump site， and at the same time maximize energy recovery， delivering much-needed power to the Ethiopian national grid.