The technology group Wärtsilä will supply its Puregas CA50 biogas upgrading plant for an innovative green gas mill project in the UK. According to Wärtsilä, the project will turn grass into gas that can be used to heat homes. The project is being led by Ecotricity, a British energy company dedicated to fighting climate change by ending the use of fossil fuels.
The order with Wärtsilä was placed in April 2022. When operational in 2023, this will be the first green gas mill in the UK, making it an important step towards creating a green economy. The proven technology process works with grass that has been broken down in a silage container for approximately two months. It is then put into a digester where it gives off a methane-rich gas, which is then fed into the domestic gas network.
The Wärtsilä biogas upgrading plant refines the gas before it is sent to the grid.
Green grass is carbon neutral in that the CO2 it absorbs whilst growing is released back into the atmosphere when the methane is burned. Fossil gas, by comparison, releases CO2 that is not in the atmosphere now, meaning that it is a net addition to atmospheric CO2. Ecotricity plans to build many more green gas mills in the future. The company calculates those 3000 installations would provide enough gas to fuel all 22 million homes that are currently on Britain's gas grid.