Cornish geothermal project leads government heat scheme

The UK’s first deep geothermal heat network is one of seven new projects to receive funding as part of a new government programme to decarbonise buildings across England.

The United Downs geothermal site in Cornwall
The United Downs geothermal site in Cornwall - GEL

Located near Truro in Cornwall, the Langarth Deep Geothermal Heat Network will use a borehole drilled to a depth of 5,275m to tap into heat from granite rocks beneath the United Downs Industrial Site. The geothermal energy will be piped around the local region to provide hot water and heating for around 3,800 homes and public facilities.


The £22m Cornwall project is one of seven to share in £91m under the government’s Green Heat Network Fund (GHNF), a scheme which opened in March 2022 to public, private and third-sector applicants in England. Anticipated to run to 2025, the GHNF has a total funding pool of £288m.

"Continuing the legacy of the first GHNF projects to be announced in December, over £91 million more targeted support has been announced from the fund today to deliver low carbon heating across the country,” said Ken Hunnisett, programme director for Triple Point Heat Networks Investment Management, delivery partner for the GHNF.

“From Cornwall to London, Reading to Rotherham, funding announced today will go far to help us reach our net zero ambitions and provide clean heating across residential and commercial buildings.”

The United Downs site in Cornwall is already under development by Geothermal Engineering Limited (GEL), with the company planning to generate baseload electricity and heat energy from the granite deep below. According to GEL investors Kerogen Capital, the site should start producing power in 2024, with the first plant delivering 2MWe of baseload electricity and up to 10MWth of zero carbon heat. GEL has plans to expand its geothermal portfolio across Cornwall, aiming to power 70,000 homes by 2028.

“We are delighted by today’s news confirming the £22m DESNZ Green Heat Network funding for the heat network at Langarth Garden Village in Cornwall,” said Jason Cheng, CEO and co-founder of Kerogen Capital. “This will help deliver one of the UK’s largest zero-carbon heat networks, and the first supplied by geothermal energy from GEL’s United Downs development. The network will benefit thousands of local residents and businesses, and save an estimated 5,000 tonnes per year of CO2.

“Geothermal can play a critical role in decarbonising heat - which accounts for 50 per cent of the UK’s energy demand – and facilitate the UK’s ambitious Net Zero and Energy Security goals. We are confident that our and GEL’s expertise will help drive this exciting sector forward.”

The full list of projects to receive support today via the Green Heat Networks Fund are: 

  • Bradford Energy Limited will receive £20m to build an air source heat pump heat network, to supply businesses and other buildings in the city centre 
  • Cornwall Council will receive £22m to develop the Langarth Deep Geothermal Heat Network – the first of its kind in the UK that will use geothermal energy from hot granite rocks beneath Cornwall to heat 3,800 local homes and public facilities in the region 
  • East Riding of Yorkshire Council will receive £12m to create the new Goole District Energy Network, that will use waste heat from a manufacturing plant to power local homes and businesses. Cutting the town’s carbon emissions by 322,000 tonnes over 40 years and creating 40 new skilled jobs
  • Rotherham Energy Limited will receive £25m to build a new Rotherham Energy Network to deliver a heating and hot water to 34 homes and businesses in the town centre 
  • Kirklees Council will receive £8.2m to create the Huddersfield District Energy Network, that will provide low-carbon heat and electricity to public and private sector buildings in and around the centre of the town, helping the council reach its goal of net zero carbon emissions by 203
  • East London Energy will receive £1.76m to expand the heat network to supply more homes in and around the Queen Elizabeth Olympic Park in Stratford
  • The University of Reading will receive £2.1m to help decarbonise its Whiteknights Campus, currently powered by a combined heat and power led district heating network