Capture and Combustion of Landfill Gas from Willawong Landfill Project

The Capture and Combustion of Landfill Gas from Willawong Landfill Project is a waste management and energy generation initiative located in the industrial suburb of Willawong, approximately 16km south of the Brisbane CBD in Queensland. Registered in March 2013, the project operates on a site with a significant history; the Willawong Landfill was formerly a hazardous waste facility and putrescible landfill that closed to the public in the late 1990s. The site is now a remediated zone often associated with Brisbane City Council's waste services and transport depots.

This project operates under the "Electricity Generation from Landfill Gas" methodology. The primary activity involves an active gas collection system that extracts methane-rich biogas generated by the decomposing legacy waste underground. Instead of allowing this potent greenhouse gas to vent into the atmosphere, the system captures and combusts it in a generator to produce renewable electricity. This process converts the methane into carbon dioxide (which has a significantly lower global warming potential) and feeds dispatchable power into the local grid, displacing fossil-fuel-based energy.

The Willawong region experiences a humid subtropical climate with high rainfall, particularly in the summer months. The site itself sits within the low-lying floodplain of Oxley Creek, historically characterized by alluvial and heavy clay soils, a soil type that is often utilized in landfill capping to prevent leaching.

An interesting facet of this project is its adaptation to the lifecycle of the landfill. Originally commissioned by LGI Limited in 2011 with a 1MW generator, the equipment was downsized to a 600kW unit in 2019 to optimally match the naturally declining gas volumes from the closed site. Despite the landfill being closed for over two decades, it continues to produce enough biogas to power hundreds of homes, demonstrating the long-tail emissions profile of legacy waste. The project transitioned from the original Carbon Farming Initiative (CFI) protocols to the 2021 methodology, ensuring its continued compliance and credit generation.