Landfill gas to energy
The EPA-licensed Melbourne Regional Landfill (MRL) collects residual waste from residential, commercial, and industrial customers. Australia produces 50 million tonnes of waste every year, with 51% being recycled and the rest of the waste going to landfill. The by-product of the residual waste is processed to safely and effectively power communities with renewable energy. In FY18, MRL powered over 28,000 Victorian homes.
Key features
MRL is a highly engineered and regulated facility that operates to the highest environmental standards to minimise impact on the community. As an EPA-licensed landfill, MRL follows stringent standards and processes. As well as household waste, solid inert waste and shredded tyres, MRL can accept quarantine waste such as food from international flights and ships. This waste is managed via deep burial into defined pits in active landfill cells.
MRL captures landfill gas from unrecyclable waste and turns it into electricity to power more than 28,400 homes in Melbourne. Our landfill gas generators combust the gas, destroy the methane, before converting it into electricity to be sent to the national grid. They have an uptime rate of 90%, which means we’re providing renewable energy into the electricity grid 24 hours a day, all year round.
How we do it
A landfill is an area divided into cells, about the size of a large swimming pool. Each cell is filled and sealed before a new cell is begun. Active landfill cells, where the compacted waste is buried, have special liners and covers to contain the gases and liquids produced by the decomposing waste so they do not pollute the surrounding area.
The decomposing waste often produces methane, carbon dioxide and a liquid called leachate. It is methane gas that we use. Methane is collected via gas collection wells that are deeply embedded into a landfill cell. The wells are kept in a vacuum state, encouraging the landfill gases to travel up the wells to the next stage.
The landfill gases are then sent to a nearby gas conditioning facility. This facility treats the collected landfill gas, removing moisture and other contaminants. Once treated, the gas is sent to our gas engines and electric generators (GenSets), to be transformed into electricity.
The generated electricity is then sent through our transformers, which increases its voltage in preparation for the next step. The generated electricity is now sent to the grid, ready to be delivered and used in your home