# Top 50 Cleantech Startups in the United Kingdom by Funding (2026)

> The 50 best-funded cleantech startups in the United Kingdom, ranked by total funding raised: $8.9B combined.

Source: https://millionrounds.com/top-lists/cleantech-startups-united-kingdom (Millionrounds; every figure on the page links to its filing or article)

- 1 [**SSE**](https://millionrounds.com/company/sse) *Founded* 1998 Perth, United Kingdom **$2.7B** last round Jun 2026
- 2 [**CuspAI** CuspAI is an innovative artificial intelligence company based in Cambridge, United Kingdom, with additional teams in Amsterdam and Berlin.](https://millionrounds.com/company/cuspai) CuspAI is an innovative artificial intelligence company based in Cambridge, United Kingdom, with additional teams in Amsterdam and Berlin. *Founded* 2024 Cambridge, United Kingdom **$950M** last round Jul 2026
- 3 [**Octopus Energy Group** Octopus Energy Group is an England-based holding company that operates businesses in areas such as energy generation and electric vehicle sales.](https://millionrounds.com/company/octopus-energy-group) Octopus Energy Group is an England-based holding company that operates businesses in areas such as energy generation and electric vehicle sales. *Founded* 2016 London, United Kingdom **$681M** last round Dec 2025
- 4 [**Newcleo** Newcleo is an atomic energy company that focuses on developing advanced nuclear energy technologies.](https://millionrounds.com/company/newcleo) Newcleo is an atomic energy company that focuses on developing advanced nuclear energy technologies. *Founded* 2021 Paris, United Kingdom **$563M** last round Sept 2026
- 5 [**Zenobē**](https://millionrounds.com/company/zenobe) *Founded* - United Kingdom **$382M** last round Jul 2025
- 6 [**Atrato Onsite Energy** Atrato Onsite Energy is a commercial rooftop solar funder.](https://millionrounds.com/company/atrato-onsite-energy) Atrato Onsite Energy is a commercial rooftop solar funder. *Founded* - London, United Kingdom **$327M** last round Apr 2025
- 7 [**Ichthion** Ichthion engaged in Development of cutting-edge technology to restore the ocean environment.](https://millionrounds.com/company/ichthion) Ichthion engaged in Development of cutting-edge technology to restore the ocean environment. *Founded* 2017 United Kingdom **$271M** last round Jan 2024
- 8 [**Field** Field is Strava for football, tennis and padel.](https://millionrounds.com/company/field) Field is Strava for football, tennis and padel. *Founded* 2019 United Kingdom **$265M** last round Sept 2024
- 9 [**AMPYR Distributed Energy** AMPYR Distributed Energy designs, constructs, owns, and operates sustainable energy technology.](https://millionrounds.com/company/ampyr-distributed-energy) AMPYR Distributed Energy designs, constructs, owns, and operates sustainable energy technology. *Founded* - London, United Kingdom **$229M** last round May 2025
- 10 [**EVC** EVC's core focus is on providing convenient, practical and reliable 'destination' charging options for its growing customer base](https://millionrounds.com/company/evc) EVC's core focus is on providing convenient, practical and reliable 'destination' charging options for its growing customer base *Founded* 2020 United Kingdom **$199M** last round Feb 2023
- 11 [**GeoPura** GeoPura is enabling the production, transport, and use of zero-emissions fuels with innovative and commercially viable technology.](https://millionrounds.com/company/geopura) GeoPura is enabling the production, transport, and use of zero-emissions fuels with innovative and commercially viable technology. *Founded* 2019 Wysall, United Kingdom **$194M** last round Aug 2026
- 12 [**Highview Power** Highview Power is a renewable energy company that develops liquid-air energy storage solutions for grid applications.](https://millionrounds.com/company/highview-power) Highview Power is a renewable energy company that develops liquid-air energy storage solutions for grid applications. *Founded* 2005 London, United Kingdom **$171M** last round Nov 2025
- 13 [**Ampergia** Ampergia Limited is a UK-based renewable energy company founded in 2021 by Sandip Sali.](https://millionrounds.com/company/ampergia) Ampergia Limited is a UK-based renewable energy company founded in 2021 by Sandip Sali. *Founded* 2021 Milton Keynes, United Kingdom **$168M** last round Jan 2022
- 14 [**First Light Fusion** First Light Fusion is a British company based in Oxfordshire, focused on developing innovative solutions for fusion energy through inertial confinement.](https://millionrounds.com/company/first-light-fusion) First Light Fusion is a British company based in Oxfordshire, focused on developing innovative solutions for fusion energy through inertial confinement. *Founded* 2011 Yarnton, United Kingdom **$167M** last round Apr 2026
- 15 [**BBOXX** Bboxx manufactures plug and play solar systems.](https://millionrounds.com/company/bboxx) Bboxx manufactures plug and play solar systems. *Founded* 2010 London, United Kingdom **$167M** last round Apr 2025
- 16 [**Mytrah Energy** Mytrah Energy (India) Limited (MEIL), a wholly owned subsidiary of Guernsey based and AIM/LSE listed MEL in India,](https://millionrounds.com/company/mytrah-energy) Mytrah Energy (India) Limited (MEIL), a wholly owned subsidiary of Guernsey based and AIM/LSE listed MEL in India, *Founded* 2009 Hyderabad, United Kingdom **$130M** last round Apr 2015
- 17 [**Connected Kerb** Connected Kerb Limited is an electric vehicle (EV) infrastructure company based in London, UK, founded in 2017.](https://millionrounds.com/company/connected-kerb) Connected Kerb Limited is an electric vehicle (EV) infrastructure company based in London, UK, founded in 2017. *Founded* 2017 London, United Kingdom **$123M** last round Jan 2025
- 18 [**GMT** GMT is an advertising company that provides media buying, user acquisition, retention, and marketing solutions with data-driven technology.](https://millionrounds.com/company/gmt) GMT is an advertising company that provides media buying, user acquisition, retention, and marketing solutions with data-driven technology. *Founded* 2012 United Kingdom **$108M** last round Apr 2026
- 19 [**Nexeon** Nexeon is a leading international developer and manufacturer of breakthrough silicon-based anode materials for lithium-ion batteries.](https://millionrounds.com/company/nexeon) Nexeon is a leading international developer and manufacturer of breakthrough silicon-based anode materials for lithium-ion batteries. *Founded* 2006 Abingdon, United Kingdom **$97M** last round Mar 2026
- 20 [**Notpla** Notpla is a London-based sustainable packaging startup founded in 2014 by Rodrigo García González and Pierre Paslier.](https://millionrounds.com/company/notpla) Notpla is a London-based sustainable packaging startup founded in 2014 by Rodrigo García González and Pierre Paslier. *Founded* 2014 London, United Kingdom **$89M** last round Jul 2026
- 21 [**Oxford PV** Oxford PV is a provider of perovskite solar cells.](https://millionrounds.com/company/oxford-pv) Oxford PV is a provider of perovskite solar cells. *Founded* 2010 Oxford, United Kingdom **$84M** last round Jul 2019
- 22 [**Hubber** HUBBER is an IT company that has created an online platform for trading platforms (online stores, marketplaces) and suppliers of goods.](https://millionrounds.com/company/hubber) HUBBER is an IT company that has created an online platform for trading platforms (online stores, marketplaces) and suppliers of goods. *Founded* 2016 United Kingdom **$81M** last round Aug 2025
- 23 [**Corio Generation** Corio Generation is a London-based offshore wind developer, established in 2022 and part of the Macquarie Group.](https://millionrounds.com/company/corio-generation) Corio Generation is a London-based offshore wind developer, established in 2022 and part of the Macquarie Group. *Founded* 2022 London, United Kingdom **$70M** last round Mar 2023
- 24 [**ARC Ride**](https://millionrounds.com/company/arc-ride) *Founded* - United Kingdom **$57M** last round Sept 2026
- 25 [**OLIO** Olio is a Digital Agency specialising in bespoke web development and provision of web services.](https://millionrounds.com/company/olio) Olio is a Digital Agency specialising in bespoke web development and provision of web services. *Founded* 2008 United Kingdom **$54M** last round Sept 2021
- 26 [**Rivan**](https://millionrounds.com/company/rivan) *Founded* 2026 United Kingdom **$47M** last round Apr 2026
- 27 [**BioticNRG** BioticNRG is a UK-based bioenergy platform focused on converting organic waste into renewable energy through anaerobic digestion and composting.](https://millionrounds.com/company/bioticnrg) BioticNRG is a UK-based bioenergy platform focused on converting organic waste into renewable energy through anaerobic digestion and composting. *Founded* 2022 Ipswich, United Kingdom **$46M** last round Jul 2024
- 28 [**Oxford Flow** Oxford Flow is a British valve manufacturer and technology innovator, established in 2015 as a spin-out from the University of Oxford.](https://millionrounds.com/company/oxford-flow) Oxford Flow is a British valve manufacturer and technology innovator, established in 2015 as a spin-out from the University of Oxford. *Founded* 2015 Witney, United Kingdom **$38M** last round Dec 2025
- 29 [**Rivan Industries** Rivan Industries is a London-based startup focused on renewable energy and synthetic fuels, founded in 2024 by Harvey Hodd.](https://millionrounds.com/company/rivan-industries) Rivan Industries is a London-based startup focused on renewable energy and synthetic fuels, founded in 2024 by Harvey Hodd. *Founded* 2023 Lewisham, United Kingdom **$36M** last round Dec 2025
- 30 [**Geothermal Engineering** Geothermal Engineering is engaged in the development of deep geothermal heat and power projects.](https://millionrounds.com/company/geothermal-engineering) Geothermal Engineering is engaged in the development of deep geothermal heat and power projects. *Founded* 2008 Redruth, United Kingdom **$35M** last round Aug 2025
- 31 [**EO Charging** EO Charging designs smart electric vehicle chargers and intelligent software for homes, workplaces, and destinations.](https://millionrounds.com/company/eo-charging) EO Charging designs smart electric vehicle chargers and intelligent software for homes, workplaces, and destinations. *Founded* 2015 Stowmarket, United Kingdom **$33M** last round Nov 2025
- 32 [**4New**](https://millionrounds.com/company/4new) *Founded* 2017 United Kingdom **$31M** last round Dec 2017
- 33 [**Aquamarine Power** Aquamarine Power is a wave energy company developing a hydro-electric wave energy converter called Oyster.](https://millionrounds.com/company/aquamarine-power) Aquamarine Power is a wave energy company developing a hydro-electric wave energy converter called Oyster. *Founded* 2005 United Kingdom **$28M** last round Sept 2011
- 34 [**Altilium**](https://millionrounds.com/company/altilium) *Founded* 2022 United Kingdom **$25M** last round Apr 2026
- 35 [**Anaphite** Anaphite is a technology company based in Bristol, specializing in solvent-free, dry coating precursor (DCP®) powders for lithium-ion battery manufacturing.](https://millionrounds.com/company/anaphite) Anaphite is a technology company based in Bristol, specializing in solvent-free, dry coating precursor (DCP®) powders for lithium-ion battery manufacturing. *Founded* 2018 Bristol, United Kingdom **$24M** last round Apr 2026
- 36 [**Open Energi** Open Energi enables public and private sector to commercialize their energy loads, improve their energy management and support their goals.](https://millionrounds.com/company/open-energi) Open Energi enables public and private sector to commercialize their energy loads, improve their energy management and support their goals. *Founded* 1999 London, United Kingdom **$22M** last round Jun 2023
- 37 [**Odqa Renewable Energy Technologies** Odqa Renewable Energy Technologies is an engineering spin-out from Oxford University, established in 2017.](https://millionrounds.com/company/odqa-renewable-energy-technologies) Odqa Renewable Energy Technologies is an engineering spin-out from Oxford University, established in 2017. *Founded* 2017 Oxford, United Kingdom **$21M** last round Mar 2026
- 38 [**Rendesco** Rendesco's mission is to transform the heating business by creating geothermal networks using ground-source heat pump technology.](https://millionrounds.com/company/rendesco) Rendesco's mission is to transform the heating business by creating geothermal networks using ground-source heat pump technology. *Founded* 2012 London, United Kingdom **$21M** last round Apr 2026
- 39 [**Nuada** We help hard-to-abate industries to decarbonise by vacuuming CO2 out of flue gas](https://millionrounds.com/company/nuada) We help hard-to-abate industries to decarbonise by vacuuming CO2 out of flue gas *Founded* 2012 Newtownabbey, United Kingdom **$19M** last round Oct 2026
- 40 [**Smarter Grid Solutions** Smarter Grid Solutions is a grid tech company that offers sustainable ways to help power companies meet the high demand for electricity.](https://millionrounds.com/company/smarter-grid-solutions) Smarter Grid Solutions is a grid tech company that offers sustainable ways to help power companies meet the high demand for electricity. *Founded* 2008 Glasgow, United Kingdom **$19M** last round Oct 2021
- 41 [**Gridcog** Gridcog is a B2B SaaS energy technology company based in London, United Kingdom, founded in 2020.](https://millionrounds.com/company/gridcog) Gridcog is a B2B SaaS energy technology company based in London, United Kingdom, founded in 2020. *Founded* 2020 London, United Kingdom **$18M** last round Jul 2026
- 42 [**Altruistiq** Altruistiq is a London-based climate technology company that offers a SaaS Sustainability Intelligence platform designed for large enterprises with complex supply chains.](https://millionrounds.com/company/altruistiq) Altruistiq is a London-based climate technology company that offers a SaaS Sustainability Intelligence platform designed for large enterprises with complex supply chains. *Founded* 2020 London, United Kingdom **$18M** last round Jul 2022
- 43 [**Tonik Energy** Tonik Energy was a UK-based renewable electricity and gas supplier founded in 2015 and headquartered in Birmingham.](https://millionrounds.com/company/tonik-energy) Tonik Energy was a UK-based renewable electricity and gas supplier founded in 2015 and headquartered in Birmingham. *Founded* 2015 Birmingham, United Kingdom **$17M** last round Feb 2019
- 44 [**Azuri Technologies** Azuri Technologies is a renewable energy company based in Cambridge, founded in 2012.](https://millionrounds.com/company/azuri-technologies) Azuri Technologies is a renewable energy company based in Cambridge, founded in 2012. *Founded* 2012 Milton, United Kingdom **$16M** last round Sept 2025
- 45 [**Eco Plastics** ECO Plastics is a reprocessor of recyclable materials sourced from waste contractors and local authorities in the UK and Ireland.](https://millionrounds.com/company/eco-plastics) ECO Plastics is a reprocessor of recyclable materials sourced from waste contractors and local authorities in the UK and Ireland. *Founded* 2000 United Kingdom **$16M** last round Jul 2008
- 46 [**Founders Factory** Founders Factory builds and funds startups together with exceptional entrepreneurs and the world's leading companies.](https://millionrounds.com/company/founders-factory) Founders Factory builds and funds startups together with exceptional entrepreneurs and the world's leading companies. *Founded* 2015 London, United Kingdom **$15M** last round Jul 2023
- 47 [**Exergy3** Exergy3 is clean-tech spinout from the University of Edinburgh.](https://millionrounds.com/company/exergy3) Exergy3 is clean-tech spinout from the University of Edinburgh. *Founded* 2023 Edinburgh, United Kingdom **$15M** last round Apr 2026
- 48 [**Samudra Oceans** Samudra Oceans is a London-based climate technology startup founded in 2022, focused on advancing ocean farming and blue carbon capture.](https://millionrounds.com/company/samudra-oceans) Samudra Oceans is a London-based climate technology startup founded in 2022, focused on advancing ocean farming and blue carbon capture. *Founded* 2022 London, United Kingdom **$14M** last round Jun 2025
- 49 [**Pandas** Pandas is a B2B platform that provides quality inventory and financing to +10M local non-grocery retailers.](https://millionrounds.com/company/pandas) Pandas is a B2B platform that provides quality inventory and financing to +10M local non-grocery retailers. *Founded* 2022 London, United Kingdom **$13M** last round Mar 2023
- 50 [**Spotless Water** Spotless Water is a UK-based company that operates the country's first self-service network for ultra-pure water dispensing.](https://millionrounds.com/company/spotless-water) Spotless Water is a UK-based company that operates the country's first self-service network for ultra-pure water dispensing. *Founded* 2016 Frimley, United Kingdom **$13M** last round Jun 2026

**Total funding** how the list is ranked

**15 November 2026** updated nightly

**Rounds we track** source: Millionrounds

Companies whose funding rounds we classed in this sector, ranked by the total they have raised in rounds we hold. Nobody pays to be on a list.

## Who backed them?

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## More cleantech lists

[See all](https://millionrounds.com/top-lists?t=Cleantech)

[*C* *AR* *E* **Cleantech startups in the United States** 480 companies · $50B](https://millionrounds.com/top-lists/cleantech-startups-united-states)[*C* *AR* *S* **Cleantech startups that raised in 2026** 276 companies · $37B in 2026](https://millionrounds.com/top-lists/cleantech-startups-raised-2026)[*C* *AR* *FE* **Cleantech startups in the United States that raised in 2026** 108 companies · $31B in 2026](https://millionrounds.com/top-lists/cleantech-startups-united-states-raised-2026)[*E* *GF* *EF* **Cleantech startups in Canada** 88 companies · $2.4B](https://millionrounds.com/top-lists/cleantech-startups-canada)[*1* *N* *P* **Cleantech startups founded in 2021** 83 companies · $3.7B](https://millionrounds.com/top-lists/cleantech-startups-founded-2021)[*FF* *S* *E* **Cleantech startups founded in 2020** 76 companies · $8.3B](https://millionrounds.com/top-lists/cleantech-startups-founded-2020)[*KF* *A* *PC* **Cleantech startups founded in 2019** 70 companies · $4.5B](https://millionrounds.com/top-lists/cleantech-startups-founded-2019)[*RE* *RP* *SE* **Cleantech startups founded in 2022** 68 companies · $3.7B](https://millionrounds.com/top-lists/cleantech-startups-founded-2022)

## More lists for United Kingdom

[See all](https://millionrounds.com/top-lists?r=United%20Kingdom)

[*SC* *N* *F* **Startups in the United Kingdom** 8,355 companies · $79B](https://millionrounds.com/top-lists/startups-united-kingdom)[*IL* *CS* *ON* **Health startups in the United Kingdom** 1,094 companies · $17B](https://millionrounds.com/top-lists/health-startups-united-kingdom)[*N* *AA* *IL* **AI startups in the United Kingdom** 835 companies · $32B](https://millionrounds.com/top-lists/ai-startups-united-kingdom)[*C* *T* *K* **IT Services startups in the United Kingdom** 816 companies · $5.3B](https://millionrounds.com/top-lists/it-services-startups-united-kingdom)[*IL* *CS* *ON* **Healthcare startups in the United Kingdom** 608 companies · $14B](https://millionrounds.com/top-lists/healthcare-startups-united-kingdom)[*IL* *CS* *ON* **Biotech startups in the United Kingdom** 588 companies · $15B](https://millionrounds.com/top-lists/biotech-startups-united-kingdom)[*F* *FC* *R* **Financial Services startups in the United Kingdom** 472 companies · $26B](https://millionrounds.com/top-lists/financial-services-startups-united-kingdom)[*FC* *R* *C* **Fintech startups in the United Kingdom** 342 companies · $23B](https://millionrounds.com/top-lists/fintech-startups-united-kingdom)