CPT has developed a patented photon-multiplier technology that enables existing silicon solar panels to generate more power by converting wasted sunlight into usable light. The drop-in solution fits into standard solar modules without any redesign or capital-intensive manufacturing changes, offering one of the most practical routes yet to increasing global solar efficiency.

The £926,000 equity investment round attracted international backing from Cambridge Enterprise Ventures, Spectrum Impact, Tybourne Capital, Providence Investment Company and SourceSquared. A £630,000 Clean Energy and Climate Technologies grant from the UKRI Innovate UK Investor Partnerships was also awarded, enabled by the participation of Cambridge Enterprise, an Innovate UK Investor Partner, in the investment round.

By converting each high-energy photon, normally lost as heat, into 2 infrared photons that silicon can absorb, CPT’s innovation can boost energy output by up to 15% while remaining fully compatible with existing solar infrastructure. It represents the first demonstration of this photon-multiplication effect at scale.

Dr Claudio Marinelli, CEO of Cambridge Photon Technology said: “This investment demonstrates strong private-sector confidence in CPT’s technology and vision. Attracting backing from leading investors across the UK, India and Asia underlines the global relevance of our approach and its potential to transform solar efficiency at scale. The Innovate UK programme provides a powerful layer of support, helping us bridge early-stage development and commercial readiness. Together, this funding positions CPT to accelerate product readiness and bring a breakthrough British innovation to the global clean-energy market.”

With this funding, CPT will expand its R&D operation in Cambridge, accelerate material testing with global industry partners, and prepare for a larger Series A raise ahead of pilot deployment. The company aims to bring its first product to market by 2028.

The Innovate UK's Investor Partnerships Programme: Clean Energy and Climate Technologies helped accelerate the commercialisation of breakthrough clean energy technologies by combining Innovate UK’s non-dilutive R&D grant funding with aligned investment from private investors.

As global solar demand accelerates and silicon PV nears its theoretical efficiency ceiling (around 28%), new solutions that enhance output power without redesigning the solar panels are urgently needed. CPT’s technology delivers that step-change – a frictionless upgrade to the world’s most established renewable energy platform.

Chris Gibbs, Investment Director at Cambridge Enterprise Ventures, said: “Cambridge Photon Technology exemplifies the kind of transformative innovation needed to accelerate the global transition to sustainable energy and address climate challenges. We are proud to have supported the company from the beginning and now in this next exciting phase of its journey.”

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