An ancient volcano deep beneath Stoke-on-Trent could help to heat more than a thousand homes. Under a plan costing £52 million, a 2.5km (1.5 mile) borehole would be drilled to an aquifer in which the water is heated naturally to at least 85C (185F). The source of the heat is thought to be a volcano 350 million years old. Professor Peter Styles, of the University of Keele, told The Sentinel: “It’s a bit like having a hot water bottle in the ground.” Stoke City Council is preparing a business case for the project. The government has pledged £20 million.