The shift toward renewable energy extends far beyond individual consumer choices, it now defines entire industries. Britain's clean energy sector continues evolving, with startups and scale-ups addressing decarbonisation challenges across offshore wind, fusion research, and beyond.

The UK hosts a dynamic ecosystem of climate innovation companies. Active clean energy businesses have doubled from 6,345 (2013) to 11,841 (2024) previously, reflecting substantial sectoral expansion.

Government policy reinforces this trajectory. The Clean Energy Industries Sector Plan targets doubling annual clean energy investment beyond £30bn by 2035, with £40bn in private capital already committed.

Global Investment Context
The necessity for green technology commands widespread recognition. The IEA projects global energy investment reaching $3.3 trillion, with approximately $2.2 trillion directed toward clean sources, nearly doubled fossil fuel allocation.

BloombergNEF reports renewable energy investment hit a record $386bn in H1 2025, driven by small-scale solar and offshore wind expansion.

Energy storage innovation accelerates rapidly. Global capacity additions are projected at 222 GWh, a 26.5% year-on-year increase, with emerging technologies like hydrogen and liquid-air storage enhancing grid flexibility. UK-based Highview Power raised £300m to construct a pioneering 50 MW / 300 MWh liquid-air energy storage facility in Manchester, scheduled for early 2026 commissioning.

Global renewable capacity additions reached 582 GW in 2024 (19.8% annual increase), with solar PV comprising 78% of installations. Total global capacity stands at 4,443 GW, led by China and other Asian nations.

UK Green Energy Sector Overview

Beauhurst currently tracks nearly 16,000 UK green energy companies, concentrated in London (3,268), the South East (1,696), and South West (1,489). Scotland, with its robust offshore wind industry, hosts 1,094 clean energy businesses.

Development Stages

High-growth UK clean energy companies skew early-stage: 31% at Seed, 24% at Venture, 27% at Established, and 11% at Growth stage. These distributions reflect the sector's comparative youth following rapid startup formation over the past decade.

Investment Trajectory

A decade ago (2015), renewable energy companies raised just £437m annually. By contrast, 2024 delivered 252 completed deals totalling £1.27bn. In 2025, £1.29bn was deployed into renewable energy companies.

Top Ten UK Green Energy Companies by Equity Raised

Rankings reflect seed, venture, growth, and established-stage private companies by total equity raised.

10. Renewable Power Capital
Founded: 2020 | Base: London | Capital Raised: £180m
This pan-European investment platform, backed by CPP Investments, develops, constructs, and owns solar, onshore wind, and battery storage projects accelerating Europe's energy transition whilst delivering stable returns.

Funding milestones include £68.4m at seed stage (2022, 56% stake), £87.8m at venture stage (2023, 38% stake), and £23.4m at growth stage (September 2024, 10% stake).

9. Venterra Group
Founded: 2021 | Base: London | Capital Raised: £219m
Venterra accelerates the global energy transition through offshore wind power, acquiring and integrating specialist firms whilst adding management expertise and capital to support scaling.

Capital deployment comprises £37.4m at seed (2021), £51.5m at venture (2022), and £100m at growth stage (2023) from First Reserve, BeyondNetZero, and others, plus £29.8m in October 2024. Funding has supported six acquisitions strengthening engineering, construction support, and consultancy capabilities.

8. Tokamak Energy
Founded: 2015 | Base: Abingdon | Capital Raised: £222m
Pioneering commercial fusion power development, this Oxfordshire company (a UK Atomic Energy Authority spin-off) targets clean, secure, affordable energy delivery by the 2030s through spherical tokamak technology and high-temperature superconducting magnets.

Across 11 equity rounds and 13 grants, major backers include British Patient Capital (Future Fund: Breakthrough), Legal & General Capital, BW Group, and Furukawa Electric. Recent rounds delivered £94.9m at growth stage (December 2023, 33% stake), following £67.1m (2020) and £19.2m (2018). Ongoing government support includes Innovate UK and US Department of Energy grants.

7. Field
Founded: 2020 | Base: London | Capital Raised: £282m
Field develops battery energy storage systems (BESS), storing renewable power and releasing it during peak demand to create greener, more flexible, reliable energy infrastructure.
Funding progression: £5.7m at seed (2021, from Giant Ventures and angels), £32.4m at venture (2022, LocalGlobe and Plural), £200m at venture (2023, led by DIF Infrastructure), plus a £42m loan facility (2025, ING Bank and Rabobank) for portfolio expansion.

6. Fidra Energy
Founded: 2023 | Base: Edinburgh | Capital Raised: £445m
Developing and operating large-scale energy storage projects supporting clean, renewable power transition, this Edinburgh company raised £445m in its inaugural September 2025 round from EIG Partners and the UK's National Wealth Fund. Capital supports the Thorpe Marsh Battery Energy Storage System (Doncaster) and additional projects including a Nottinghamshire site.

5. OVO Group
Founded: 2015 | Base: Bristol | Capital Raised: £459m
Among the UK's largest energy companies, OVO powers homes and businesses with clean, affordable energy focus. Founded in 2009, recent funding includes £200m (July 2023) from Mayfair Equity Partners and Morgan Stanley Investment Management.

Active acquisition strategy includes SSE's retail arm (£500m, 2020), CORGI HomePlan, VCharge, and EV charging app Bonnet (2023). Seven grants from Innovate UK and Sky Zero Footprint Fund support low-carbon heating, energy flexibility, and innovation projects.

4. ITM Power
Founded: 2001 | Base: Sheffield | Capital Raised: £481m
This global hydrogen energy solutions leader manufactures integrated systems for clean fuel production and storage. Founded in 2001 and AIM-listed in 2004 (first UK fuel cell company public listing), ITM Power operates from Sheffield with offices across Germany, France, USA, and Canada.

Major raises: £61.1m at growth (2019, Linde-led), £172m (2020, Snam and others), £250m (2021, BofA Securities and Investec). The company has received 39 grants from Innovate UK and UK energy sector bodies. In 2021, ITM spun out Motive Fuels; in 2025, it featured on the FT1000 as one of Europe's fastest-growing companies.

3. GRIDSERVE
Founded: 2016 | Base: Iver | Capital Raised: £623m
This sustainable energy supplier operates the GRIDSERVE Electric Highway featuring Electric Forecourts® and Electric Hubs, making zero-carbon transport accessible whilst running an EV leasing business supporting clean mobility transitions.

Funding includes £16.7m (2021, Novuna), £346m equity (2022, Infracapital-led), £300m loan facility (2023, NatWest, Lloyds, Santander, National Wealth Fund), and £55.8m (March 2025, Infracapital, Mitsubishi HC Capital UK, TPG). Multiple Innovate UK grants include £5.1m (2019) and a record £33.5m (2023) supporting solar, storage, and EV charging projects.

2. Zenobē
Founded: 2016 | Base: London | Capital Raised: £1.02bn
A leading UK battery storage and EV charging infrastructure provider, Zenobē delivers clean power and sustainable transport through large-scale batteries supporting grid decarbonisation and transport electrification.

Early investment: £37.6m at seed (2017, Tiger Infrastructure Partners), venture-stage rounds from JERA, TEPCO, and Infracapital. December 2023 brought a £476m growth-stage round from KKR and Infracapital, among the largest UK energy transition private capital injections. Recognition includes HolonIQ's Europe Climate Tech 2023, Sifted 100: UK and Ireland 2024, BusinessCloud FactoryTech 50 2024, and The Sunday Times Tech 100 2025.

1. Octopus Energy
Founded: 2015 | Base: London | Capital Raised: £1.22bn
Part of the broader Octopus Group, Octopus Energy ranks among Britain's largest energy transition companies, delivering affordable, sustainable power whilst reshaping global energy systems.

Key fundraisings: £182m (2020, Origin Energy and Tokyo Gas), £636m (2021, CPP Investments, Generation Investment Management, others), £631m (December 2023). Government and Innovate UK grants include £2.8m (2018) for clean energy innovation. The company has completed 20+ global acquisitions including Exagen Group (UK), Kwest (Germany), Jedlix (Netherlands), and Energetiq (Australia).

High-growth recognition includes E2E Job Creation 100 (2023), Lazard T100 European Venture Growth Index (2024), and BusinessCloud's EnviroTech 50 (2024).

Sector Outlook

The net zero sector expanded 10.1% in 2024, contributing £28.8bn to the economy whilst supporting nearly one million jobs with above-average wages. Government policies continue reinforcing growth in 2025. The Clean Energy Industries Sector Plan's "build it in Britain" approach pairs £700m in supply-chain investment with mandates to double annual clean energy investment to £30bn by 2035.

Great British Energy's establishment via the Great British Energy Act 2025 signals strategic commitment to embedding renewable generation throughout the national energy system. Contracts for Difference scheme reforms, including extended contract lengths and a £544m Clean Industry Bonus, aim to maintain offshore wind targets whilst attracting investor interest.

Energy security strengthens through nuclear extensions and flagship projects. Heysham 1 and Hartlepool plants operate until 2028, delivering an estimated 12 TWh. Sizewell C advances with £14.2bn government funding, promising power for six million homes and 10,000 jobs.

Challenges persist: policy uncertainty and contract stability concerns may deter investment and slow progress. Skills retention worries emerge as sector specialists leave amid stagnating renewable projects and high taxation. Nevertheless, strong growth, public-private investment, and sector-wide momentum position the UK favourably to lead the green energy transition.

GS Verde Group: Strategic Advisory for Clean Energy Growth

Britain's green energy sector expands rapidly through sustainability targets, investor demand, and technological innovation. Beauhurst research confirms that green energy businesses face significant opportunities alongside growth challenges.

GS Verde Group helps clean energy businesses navigate competitive markets with clarity and confidence. Our integrated team delivers corporate finance, legal, tax, accountancy, and communications expertise, providing seamless end-to-end service for investment raising and successful exits.

Further insights: Explore the UK green energy landscape at: https://www.beauhurst.com/blog/green-energy-companies-uk/