What is an AD Plant?

Housed in a specially-designed building, most of the plant consists of a large, airtight digestion chamber heated to approximately 38-40°C. A carefully balanced mixture of organic matter is pumped into the chamber – this can include quite a range of different materials, including food waste and cooking oil, but here at Willowglen we use a 50/40 mixture of cattle dung (and straw) from our farm and maize or whole-crop rye and grass. The organic matter is liquidised by the addition of stored rainwater, and the AD process turns this mixture into gas (known as biogas), a highly versatile renewable fuel. The biogas is piped to the plant’s cogeneration unit, where it’s used to produce heat and electricity for Greendale Business Park and Farm Shop. The solid byproduct of the AD process is used as organic fertiliser on our farmland. In other words, an AD plant is a great way to convert waste materials into clean energy.