Waste heat from Scottish supercomputer to be reused to warm homes

Image: Neil Hanna. Pictured: A disused, flooded mine.

According to the University of Edinburgh, where the supercomputer is based, it currently releases up to 70GWh of excess heat per year. This level of heat wastage could almost quadruple once a next-generation supercomputer is installed in the coming years.

The University is keen to see this heat reused. This would provide benefits including lower heating bills for the user of the reused heat, plus lower greenhouse gas emissions.

“With more than 800,000 households in Scotland in fuel poverty, bringing energy costs down in a sustainable way is critical, and using waste heat could be a game-changer,” said Professor Christopher McDermott, who works on geoscience in his day-to-day role and is the lead academic for the project.

The University is working with industry and academic partners from elsewhere in Scotland, plus the US and Ireland, to trial an innovative heat capture, storage, transportation and reuse system.

This trial will cost around £2.6m to deliver and will be spearheaded by TownRock Energy. The funding is coming from a mix of sources including Scottish Enterprise and the USA’s Department of Energy.

The system set to be used in the trial will augment the cooling process for the supercomputer to transfer wasted heat into mine water within disused mine networks under Edinburgh. This heated water could then be transported around the mine system at a maximum of 40C.

Heat from the water will be used to serve heat pumps within homes or other buildings. Preliminary calculations show that the waste heat could serve at least 5,000 buildings across the city.

If successful, the study could provide a global blueprint for converting abandoned flooded coal, shale and mineral mine networks into underground heat storage. One-quarter of the UK’s homes are sited above former mines.

“This project opens up the potential for extracting heat stored in mine water more broadly. Most disused coalmines are flooded with water, making them ideal heat sources for heat pumps,” said Professor McDermott.

Heat pump picture

The UK Government is aiming for annual heat pump installation rates to reach 600,000 by 2028, up from 55,000 in 2021.

It has repeatedly been warned by its own climate advisors that it is not on track to deliver, and Ministers must make more concerted efforts to grow the UK’s skills base and manufacturing capacity to bring down costs.

Last month, the Government almost quadrupled funding available through its Boiler Upgrade Scheme, which provides homes with grants to switch from fossil fuel heating to heat pumps, in a bid to address some of these issues.

This change came after Prime Minister Rishi Sunak expanded the maximum amount of grant funding each household could claim under the Scheme earlier this year, from £5,000 to £7,500.

Sunak stated at the time that the upfront cost of a heat pump was still a deterrent to many homes and argued that the general public should not have to bear the burden of net-zero transition costs – particularly in a cost-of-living crisis.

Heat pumps typically cost at least £10,000 upfront for a UK household.

Related news: Octopus Energy invests £200m in data centre heat recycling technology