Stock Photo - The control panels for the biogas boilers at Daveyhulme wastewater treatment plant in Manchester, UK United Utilities Daveyhulme plant process´s all of Manchester sewage and deals with 714 million litres a day The sewage sludge from the plant is put in huge biodigesters which produce biogas from the human waste This biogas is 70 methane a potent greenhouse gas that is more than 20 times efficient as a greenhouse gas than C02 The biogas is burnt on site in a heat and pwer plant, preventing its release into the atmosphere The plant generates around 7 megawatt of electricity per day from the renewable biogas