Heat from London Underground tunnels will be used to keep homes in Islington warm under a new scheme, it is a joint project between Islington Council, TfL and engineering firm Ramboll. Warm air from a disused Northern Line station will support a heat network supplying up to 1,000 homes and businesses by the end of the year.

A heat pump will capture "waste heat" from a ventilation shaft on City Road, which currently pumps out air at 18C to 28C (64F to 82F). This will then be used to supply heat and hot water to properties.

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