Sunderland City Council has extended by a month a tender for drilling of pilot boreholes for a planned heat network that will make use of heat from the flooded Wearmouth Colliery.
The project, which has support from the Green Heat Network Fund, will lift and return the mine water, which is at 200degC, from 600m below the surface. It will use heat exchangers and a heat pump to provide water at 700degC to users, which will include an 8.1km district heating network.
It is seeking a drilling contractor with a demonstrable track record of successfully drilling through and into mine workings at up to 600m depths for the development and the exploration phases, consisting of the drilling and testing of the boreholes.
The project won GHNF funding in 2021 and the initial schedule planned to drill test boreholes in the second half of 2022 so that the first phase of the heat network would start up in autumn 2024.