Thousands of homes in south-west London could soon be warmed by the waste from their local sewage works as part of England’s first poo-powered district heating scheme.
Thames Water hopes to harness the heat of human waste from its treatment plant in Kingston upon Thames to warm more than 2,000 new homes that form part of a regeneration plan for the borough’s Cambridge Road estate.
Typically, the water company flushes the clean warm water that remains after it has treated its customers’ sewage back into a local river system as effluent. But under the new plan it will funnel the warm water to an energy centre where the effluent will help heat the water destined to warm local homes.
The new Thames Water energy centre will use heat pumps to boost the temperature of the water higher, and heat exchangers to transfer the heat of the waste water to a separate system of water pipes which will carry hot water to the district heating scheme.
Caroline Kerr, the leader of Kingston council, described the scheme to turn waste into clean energy as a “groundbreaking” step to help make the homes on the Kingston estate some of the greenest in the country.
By using renewable poo-powered heating in place of fossil fuel gas, the scheme could save 105,000 tonnes of carbon dioxide emissions over 30 years, according to Thames, the equivalent of 157,000 return flights from London to New York or more than 15,000 car journeys around the world.
“It’s a first for England and shows we are serious about reducing carbon in the borough. This is a real opportunity to be bold and ambitious for future generations,” she said.
The district heating scheme could be expanded so that public and commercial buildings in Kingston town centre also feel the warmth of human waste.
Sarah Bentley, the new chief executive of Thames Water, said the renewable heat from the water company’s sewer network is “a fantastic resource, so it’s vital we are a leading player in energy transition and unlock the full potential of ‘poo power’.”
She said she was confident that the Kingston project could help unlock the heating potential of sewage across the country as the government prepares to ban gas boilers in new housing developments from 2025.
The UK’s first district heating scheme to be warmed by human waste was set up in 2015 by Scottish Water to provide 95% of the heat required by Borders College in Galashiels.