Greentech is where climate policy meets private capital. The companies in this ranking are building batteries, charging networks, hydrogen plants, carbon capture technology and the materials meant to replace plastic.
And the funding has held up better here than in most sectors. The companies included in this ranking have raised £13.9b across 632 equity rounds, with 71% of it arriving since 2020.
In this ranking, we’ve used the Beauhurst platform to identify 100 UK-headquartered greentech companies that meet our methodology, then ranked them by the total equity funding they have raised.
That distinction matters. This is not a list of the UK’s largest energy companies. Instead, it provides a snapshot of the technology businesses working on climate and environmental problems that have attracted the most equity investment.
What is greentech?
Greentech, as the name suggests, refers to the use of technology to combat climate change and other pressing environmental challenges. Greentech (or cleantech) companies are focused on developing or deploying these technologies to reduce our negative environmental impact on the world.
This emphasis on innovative tech is what sets greentech companies apart from some of the UK’s other high-growth sustainable companies.
UK greentech companies: sector overview
The companies analysed for this article broadly fall into three groups.
The first is energy generation, storage and grid. These companies build batteries, storage projects, renewable generation and the software that balances it all against demand.
The second is transport and electrification. These companies make charging networks, electric motors and the systems that manage vehicle charging.
The third is materials, waste and carbon. These companies capture or convert carbon, recycle plastics and textiles, and build the measurement and ratings infrastructure that carbon markets depend on.
On the Beauhurst platform, 53 of the 103 companies analysed are classified as renewable energy businesses. Energy management and reduction applies to 37, energy storage to 31 and manufacturing to 27. Companies can operate across more than one classification.
There are 103 companies in this cohort, compared with 42 at the end of 2015. That is growth of 145% over a decade.
This is also the most physically substantial cohort we have ranked. Most of these companies manufacture something, install something or operate infrastructure, which shows in how they are funded and how long they take to scale.
Key findings
The greentech companies included in the analysis have raised £13.9b across 632 equity rounds.
Centrica leads with £1.13b, followed by GRIDSERVE (£623m), ITM Power (£521m), Highview Power (£507m) and OVO Group (£459m).
Funding is spread more evenly here than almost anywhere else in this series. Centrica accounts for 8% of the total, the top five for 23% and the top 10 for 38%. Thirty-six companies have raised more than £100m, and the hundredth company on the list has raised £35.0m — by some distance the highest entry bar we have recorded.
But who put the money in is more revealing than who sits at the top. In most of the sectors we have ranked the answer is venture capital. Here it is the state and the infrastructure market.
The sector’s funding profile is unlike anything else in this series. The largest backer by value is the National Wealth Fund, which has participated in rounds totalling £1.46b, followed by the infrastructure investor Infracapital at £1.25b and KKR Private Equity at £792m. Venture capital is not what is funding this sector at the top end.
The pattern holds further down. Legal & General Capital and Parkwalk Opportunities EIS Fund have each backed 13 rounds, ahead of Crowdcube on 12 — the only time a crowdfunding platform has appeared among the most active investors in any of our rankings.
Greentech is also the most mature cohort by stage, without being the oldest. Some 53 of the 103 companies are at growth stage, with 27 established and 20 at venture. Only two are at seed. No company in the ranking has died or stalled, and just one has exited.
That combination of infrastructure capital and growth-stage weighting describes a sector in build-out rather than discovery. These companies are largely past proving that the technology works, and are now funding factories, charging networks and storage sites.
Investment peaked in 2023 at £2.52b, the only sector in this series to peak that year. The pattern since has been steady rather than declining, with £2.14b in 2025 and £1.02b by 22 September 2026.
The geography is the broadest of any technology ranking we have produced. London accounts for 43 of the 100 companies named, the South East for 20 and the East of England for 11, leaving more than a quarter of the list outside the golden triangle. The sector reaches 12 regions, including eight companies in the South West and four in Yorkshire and the Humber.
Environmental credentials are, unsurprisingly, dense. Beauhurst records clean and renewable energy signals against 71 of the companies and environmental accolades against 66, with green transport and green infrastructure signals against 23 each.
