Wednesday 1st October 2025, 1:17pm
The University of Edinburgh's renewable energy spinout, SeaWarm, has secured £550,000 in funding to expand its heating system to cut fossil fuel use and slash CO2 emissions by up to 90% in Scotland’s communities.
The investment includes £250,000 from Equity Gap, one of Scotland’s leading angel investment syndicates, £250,000 from Scottish Enterprise, and £50,000 from Old College Capital, the University of Edinburgh’s in-house venture investment fund.
The Scottish clean-tech company is born out of research at the University, and is now based at Roslin Innovation Centre's Agri Field Station.
SeaWarm is developing modular, low-cost heat exchangers that harness renewable energy from rivers, lochs, seawater, and minewater.
The technology adapts traditional heat pump principles to water sources rather than air or ground, offering a more stable, efficient, and resilient solution for challenging environments.
Its systems are specifically designed for rural and coastal communities, helping to cut heating bills and reduce carbon emissions while supporting the transition to net zero.
SeaWarm was co-founded by Professor Christopher McDermott, of the University of Edinburgh’s School of Geosciences, former University hydrogeologist Dr Gus Fraser-Harris, and CSM Plumbing and Heating’s Cameron Muir.
The system works like a conventional heat pump, but instead of using air, it uses water, which provides more stable temperatures, greater efficiency in cold weather, and reliable performance.
SeaWarm’s pods capture the natural energy released when water freezes, making them highly efficient even in the coldest conditions. Its modular units are compact, cost-effective to install, and designed to overcome coastal challenges such as salt corrosion, expensive drilling, and noise.
Each modular unit is roughly similar in size to a domestic oil tank, being two metres in diameter and 1.5 metres high, making it easy to install, simple to scale, and cost-effective for a wide range of sites.
They are resilient in icy conditions, deliver warmer heat on cold days, and can be easily self-serviced by owners. By drawing just 3°C from about one litre of water per second, the unit produces 13 kW of heat, enough to comfortably warm most small and medium-sized homes.
Compared with oil and gas, SeaWarm’s technology cuts CO2 emissions by up to 90 per cent, and around 70 per cent versus electricity. Over the next five years, the company aims to help minimise fuel poverty in coastal communities, reduce emissions by 20,000 tonnes, and save 10 MWh of electricity annually.
The company is targeting high heat demand commercial sites such as marinas, hotels, leisure centres, ferry terminals, museums, community buildings, and horticulture facilities, with the long-term aim of expanding into domestic markets. Demonstration sites already include Port Edgar Marina, LAR Housing Trust in South Queensferry, Growforth Ltd in Hillend, and the Museum of Lead Mining in Wanlockhead.
“Our mission is to bring affordable, renewable heating to communities most exposed to rising costs and carbon-intensive systems. Scotland’s coastal communities are our immediate focus, where we aim to establish a strong track record before expanding across the UK, Europe, and internationally.
"This funding allows us to accelerate growth, build partnerships, and deliver practical, cost-effective solutions that cut emissions by up to 90 per cent while lowering bills for households and businesses. While our near-term focus is heating, the same technology can also deliver cooling, a huge global opportunity as demand rises toward 2050.”
Professor Christopher McDermott, the University of Edinburgh’s School of Geosciences“Heating and cooling are among the largest contributors to household costs and carbon emissions. SeaWarm’s technology provides a practical, scalable solution with strong potential to make a measurable difference. We are delighted to support the company’s next stage of growth alongside Scottish Enterprise and Old College Capital, and to continue Equity Gap’s track record of backing innovative Scottish businesses with global potential.”
Fraser Lusty, Managing Director at Equity Gap“We previously supported SeaWarm through our High Growth Spinout Programme aimed at academic teams with strong commercially viable propositions. Our additional support now as an investor really underscores our commitment to creating an internationally competitive energy transition industry in Scotland.
"By investing in technologies such as clean heat we can help Scottish companies drive innovation and capitalise on the significant economic opportunities linked to the shift from fossil fuels to renewable energy.”
Derek Shaw, Director Entrepreneurship and Investment at Scottish Enterprise“It’s a fantastic team effort when a company spins out, involving EI’s business development support, technology transfer and early-stage funding from OCC, as well as, of course, the cutting-edge research and inventions of the University’s academics.
“Investment from Scottish Enterprise and Equity Gap now enables SeaWarm’s team to go on to help meet the world’s sustainable energy challenge, starting with Scotland’s coastline, with this exciting new technology.”
Lizzie Withington, Director of Venture Creation at Edinburgh InnovationsHeating and cooling account for over 40 per cent of UK energy consumption, yet many rural and coastal communities remain reliant on costly, carbon-intensive systems. SeaWarm addresses these challenges with a modular, low-impact design tailored for the unique demands of coastal environments.
The Scottish market is estimated at £340 million, with global heating and cooling demand expected to exceed £100 billion by 2028, providing strong growth potential for SeaWarm as it scales production, strengthens installer and distributor partnerships, and expands internationally.