UK startup HexSeed Technology raised over €700k (£600k) in early-stage funding led by Carbon13, with Net Zero Technology Centre and Vento Ventures also participating.
The raise unlocks a previously provisional Partnership Grant from Innovate UK and will fund development of diamond-coating technology for gallium nitride (GaN) chips used in AI data centers.
The IEA projects data center electricity consumption could reach 945 terawatt-hours (TWh) by 2030 as AI-optimized facilities scale up.
AI’s insatiable appetite for power has a heat problem, and a small UK startup just landed real money to help fix it. HexSeed Technology has raised over €700k (£600k) in early-stage funding, led by climate-tech investor Carbon13, with additional backing from Net Zero Technology Centre and Vento Ventures. The raise also unlocks a previously provisional Partnership Grant from Innovate UK, awarded on a provisional basis earlier this year — meaning the grant funding is now confirmed as accessible rather than merely pledged.
Chasing the Heat Draining AI’s Power Grid
Gallium nitride (GaN) transistors convert power far more efficiently than the silicon devices they’re replacing, but they run hot, and heat is the main barrier keeping GaN from reaching its full potential. Diamond is the best-known thermal conductor, but growing it conventionally requires temperatures that would destroy a finished semiconductor device. Working with University of Bristol researchers Paul May and Martin Kuball, HexSeed — founded in late 2025 by CEO Mark Tandy, CTO Dr Leonardo Santoni, and COO Dr Michael Glerum — is developing a low-temperature microwave plasma process to grow diamond coatings directly onto finished GaN devices. The company notes data centers already consume a significant share of global electricity, with the IEA projecting that figure could hit 945 TWh by 2030 as AI-optimized facilities scale up.
What This Means for Your Portfolio and Wallet
Rising data center energy costs are a real margin risk for cloud and AI companies, costs that can eventually filter down to consumers through pricier subscriptions or services. Efficiency technologies like HexSeed’s diamond coating represent an emerging niche within the broader AI infrastructure buildout that investors tracking the sector may want to watch, even at this early, pre-revenue stage.
Strategic Positioning & Defense Ideas
Early-stage startup investments carry high risk, so diversification across the broader AI and tech infrastructure sector — rather than concentrated bets on single unproven names — remains a standard educational approach, alongside maintaining adequate cash reserves. Disclaimer: This analysis is for educational and informational purposes only and should not be construed as financial or investment advice.
What to Watch Next
Watch for HexSeed’s progress moving from lab demonstration to working GaN devices, further Innovate UK grant disbursements, and broader trends in AI data center energy consumption. Full details via EU-Startups.
