New energy source in old mines 

DISUSED mines in the area could start providing energy again – without removing a single lump of coal.

South Gloucestershire Council is investigating the potential use of former mine workings in the district as a source of renewable heating and cooling for buildings. 

And old workings around Lyde Green, Emersons Green and south of Staple Hill are among those identified as “areas of interest” by the government’s Coal Authority. 

Old mines are flooded with water, which is naturally heated by underground geological activity. 

The council believes the heat could be tapped, to supply either “single buildings such as schools, hospitals and offices, or a heat network serving multiple buildings or a district”.

The process would involve using pumps to raise the temperature to the level required for heating and hot water.

The Coal Authority has made an initial study of records of local disused and abandoned coal mines, which “identified a number of areas of interest”.

The first two it will investigate are between Easton, Speedwell and Fishponds in Bristol, and between Hanham and Oldland Common in South Gloucestershire.

The third and fourth include Kingswood and Soundwell, up to the fringes of Staple Hill, and an area around Lyde Green and Emersons Green, which covers the Parkfield and Brandy Bottom collieries that were in use up until the 1930s.

South Gloucestershire Council is now looking for funding to undertake a further study of the areas believed to have the greatest potential, to “better understand the size of the energy resource and investigate how it could be best utilised”. 

The council believes up to 26,000 homes and businesses are near to former mine workings: it says there are 42 coal seams and more than 1,000 mine entrances in the area between Mangotsfield, Westerleigh and Kingswood alone.

Council climate emergency manager Barry Wyatt said: “We know there are extensive mine workings across South Gloucestershire – what we need to understand now is just how big the energy resource is and how we could make best use of it.”

Council leader Toby Savage said: “One hundred years after South Gloucestershire’s mines closed, they may yet be part of the solution to the climate and our move towards becoming carbon neutral.”

The Coal Authority has used written records such as maps of mine workings, geological and water data to assess which mines are likely to have flooded since closure. 

As yet, there has not been any physical investigation of any of the mines. 

A council spokesperson said more work now needs to take place to understand how much heat is available and whether future demand would make it economically viable, including looking at experiences elsewhere in the UK and Europe.