A small town located in the West of England is lighting the town’s streets through an innovative solution of converting dog excrement into biogas.
Retiree Brian Harper has developed a 100 per cent circular solution to recover the dog excrement deposited on the pavements in his home town of Malvern to produce the biogas used to power the town’s streetlights.
Anaerobic digestion of waste, especially animal excrement, is not new, but the peculiarity of Harper’s solution lies in its local scale.
Since November 2017, residents of this Worcestershire town are invited to drop bags of dog excrement down a hatch at the bottom of the town’s streetlights. All they need to do is pull a level to lower the package into a sealed tank about the size of a washing machine, which is an anaerobic digester.
Through the oxygen-free decomposition process in this tank, the excrements generate biogas composed of 60 per cent methane. The digester is directly connected to streetlights to power them with the methane produced and light up at dusk.
The initiative has already seen success thus far, with 10 small bags of excrement are enough to supply the streetlights with enough energy for two hours of lighting every evening, significantly reducing the town’s gas costs.
The town estimates that the streetlights will consume 70 per cent less gas by the end of 2018.
Neighbouring farmers also recover the digestate left behind from the process to use as fertiliser.