Waste to Wealth: Cape Town’s Innovative Approach

Key Takeaways

• The Coastal Park Landfill in Cape Town has been transformed into a gas-to-energy plant, generating electricity for over 4,000 houses.
• The project reduces air pollution and earns carbon credits, with over R36m worth of credits earned so far.
• The plant aligns with Cape Town’s goals to reduce greenhouse gas emissions and increase the share of cleaner energy in the city’s supply mix.
• The project has a limited lifespan, but the waste will continue to produce methane for some time after the landfill is closed.
• Renewable energy has more than tripled in South Africa in the past decade, with smaller-scale options like landfill gas-to-energy plants complementing larger wind and solar developments.

Introduction to the Gas-to-Energy Plant
Flocks of gulls and ibises wheel above the Coastal Park Landfill, where dump trucks tip out mountains of trash. The smell of rotting food escapes as compactors grind people’s garbage into the ground, where the waste will become a new source of electricity for Cape Town. The new gas-to-energy plant, officially opened on November 12, has multiple benefits, including less air pollution for surrounding communities. Cape Town mayor Geordin Hill-Lewis stated that the city is "just getting started with these win-win projects, which produce electricity, reduce emissions and generate carbon credit revenue to pump back into infrastructure and waste management."

The Benefits of the Project
The gas-to-energy project aligns with Cape Town’s goals "to reduce greenhouse gas emissions and increase the share of cleaner energy in Cape Town’s supply mix." Landfill gas contains methane, a potent greenhouse gas, 25 times more harmful than carbon dioxide in terms of global warming contribution. By extracting methane gas from the landfill to generate power, the project reduces the harmful emissions overheating the planet and earns "carbon credits" as a result. So far, more than R36m worth of carbon credits have been earned. The project also has a positive impact on the surrounding communities, reducing air pollution and improving the overall environment.

How the Plant Works
The power produced by the plant is small, but the impact is significant. Each of the two gas engines generates the same number of kilowatts as the height of Table Mountain: 1,067. The plant works by extracting methane from the landfill through deep "gas wells" and feeding it into the main line that runs to the gas engines. The flow and composition of the gas are constantly monitored, and oxygen content must stay low to avoid the risk of an explosion. The plant is designed to be efficient and safe, with a detection system constantly monitoring the air for methane and a red emergency stop button that can shut the whole operation down with a push.

The Future of Renewable Energy in South Africa
The Coastal Park Landfill gas-to-energy plant is one of the smaller-scale options for renewable energy in South Africa, complementing the massive development of wind and solar. Renewable energy has more than tripled in South Africa in the past decade, and this project demonstrates the potential for landfill gas-to-energy plants to contribute to the country’s energy mix. David Cornish, general manager of the city’s plant operations and maintenance contractor Energy Systems SA, estimates that roughly 40% of landfill gas sources have been tapped in South Africa, but there is still great potential for further development.

Challenges and Opportunities
Landfill gas-to-energy plants have a limited lifespan after a landfill is closed, however, the waste continues to produce methane for some time. The city plans to invest a further R82m to implement gas engines at Vissershok, another of the city’s major landfills, over the next three years. WWF-SA senior technical specialist for climate action, James Reeler, said that the project demonstrates how better waste management can benefit people and the climate. "First prize is always to divert waste from the landfill in the first place… and there is a large portion of waste that goes to landfill that can be profitably recycled and reused. However, capturing the methane and using it for energy is a good alternative." The project highlights the importance of innovative solutions to waste management and the potential for renewable energy to contribute to a more sustainable future.