SolarSub Announces £1.34 Million Funding Round to Advance Passive Solar Cooling Technology
Edinburgh, UK - September 2026 - SolarSub Ltd, a UK solar technology company developing passive cooling solutions for photovoltaic modules, has completed a £1.34 million funding round to accelerate the development and commercialisation of its technology.
The round was led by Sustainable Ventures, with participation from Zinc VC, Scottish Enterprise, Old College Capital - the University of Edinburgh’s venture investment fund, SFC Capital and the British Business Bank, alongside support from Innovate UK’s Investor Partnership programme.
Solar PV has a heat problem. As solar panels become hotter, they generate less electricity and degrade more quickly, reducing both energy output and lifetime value.
SolarSub is developing passive cooling technology designed to keep solar modules closer to their optimal operating temperature. Requiring no pumps or moving parts, the technology increases energy generation, reduces temperature-driven degradation and improves the long-term economics of solar projects.
The funding will support the next phase of SolarSub’s technical development and real-world validation programme, including further product development, independent testing and deployments with research, utility and industry partners.
Over the coming months, SolarSub, which was founded by two University of Edinburgh Engineering graduates, will undertake trials across multiple international locations as it works towards commercial-scale deployment.
Previous testing has demonstrated significant performance improvements under high-temperature conditions. Trials at the University of Edinburgh’s FloWave ocean energy research facility recorded an energy uplift of up to 17.5%, while outdoor testing at Heriot-Watt University’s Dubai campus recorded peak gains of up to 19%.
Sebastiaan Schalkwijk, CEO and Co-Founder of SolarSub, said:
“I’d like to thank all of our investors and supporters for backing us as we move into the next stage of SolarSub’s development. It’s been great to see the technology progress from the early days of research at the University of Edinburgh to the point where we’re now preparing for larger-scale trials and commercial deployment.”
James Taylor, Co-Founder and COO of SolarSub, said:
“I am immensely proud of the team in getting to this point. This investment allows us to move from successful technical validation into the next stage of real-world deployment. Our focus will now shift to demonstrating the technology at increasing scale and building out our commercial adoption with industry partners.”
Joshua Armistead-Wood, Investor at Sustainable Ventures, said:
“The challenge of energy generation is one that, unsurprisingly, remains at the top of our agenda, particularly at a time of increasing price volatility. The solution the SolarSub team is developing stood out to us because, instead of trying to reinvent the wheel, they are focused on one simple root of inefficiency within existing solar systems: excess heat. We have been impressed by what the team has achieved to date and are excited to work with them as they deliver the next stage.”
Derek Shaw, Director Company Funding & Investment at Scottish Enterprise, said:
“Our investment in SolarSub Ltd underscores our commitment to creating an internationally competitive energy transition industry in Scotland. By supporting ambitious companies in areas such as clean energy technology, we can help them drive innovation and capitalise on the significant economic opportunities linked to the shift from the production and consumption of fossil fuels to sources of renewable energy.
The company is initially targeting the floating solar market, where direct access to water provides a strong environment for passive thermal management, before expanding the technology into the wider utility-scale solar market.
SolarSub has already worked with organisations across the solar, utilities and research sectors and is progressing further validation programmes in the UK and internationally.
The funding will also support the expansion of SolarSub’s engineering capability as the company develops the technology for manufacture, certification and commercial deployment.
About SolarSub
SolarSub is a UK solar technology company developing passive cooling technology for photovoltaic modules. Its technology is designed to reduce module operating temperatures without pumps or moving parts, increasing energy yield while reducing heat-related degradation.
SolarSub is initially focused on floating solar applications, with a longer-term objective of integrating its technology into utility-scale photovoltaic modules globally.
Media enquiries:
James Taylor
Co-Founder & COO, SolarSub
jamestaylor@solarsub.co.uk
www.solarsub.co.uk
About Scottish Enterprise
Scottish Enterprise (SE) is Scotland’s national economic development agency and a non-departmental public body of the Scottish Government. It supports businesses to innovate and scale to transform the Scottish economy by focusing on new market opportunities through targeted investment, innovation and internationalisation. Follow us on LinkedIn.
