The City of Cape Town is nearing the production of electricity from landfill gas, also known as waste-to-energy.
Although only a small amount of electricity will be produced at this stage, the successful implementation of this project is an important milestone in the journey towards overall sustainability, the city says.
Urban Waste Management MMC Alderman Grant Twigg and Energy MMC Councillor Beverley Van Reenen, on March 15 visited the Coastal Park Landfill site to check on progress at the city’s waste-to-energy project.
Engines have been delivered to site and are being connected to the landfill gas extraction system that has been operational since March 2018.
It is expected that the project will generate about 2 MW that will be added to the city’s grid, and offset some demand from State-owned utility Eskom.
As 2 MW is only a very small fraction of the city’s total demand, it is unlikely to provide extra protection from load-shedding or enable a reduction in tariffs.
It is, however, noted as an important step forward in the city’s mission to reduce reliance on the State-owned power utility and meet emission reduction targets.
HOW IT WORKS
The project works on the combustion of landfill gas, which is primarily made up of methane, which has a global warming potential 25 times greater than carbon dioxide. Perforated pipes, or “wells”, are dug into the landfill site to extract the gas.
The wells are then connected to the flare compound, where it is combusted or diverted to a gas engine to generate electricity.
If gas were not used in the engine, it would be flared.
The project has also been designed in such a way that the city can earn carbon credits. A carbon credit is earned when an entity destroys 1 t of greenhouse gas that would otherwise be released into the atmosphere, and they can be sold as emission offsets under the carbon tax through the Carbon Offset Administration System.
“We definitely have a long way to go as a society before we reach sustainability, but projects like this give hope that with human creativity anything is possible,” said Twigg.