| GPC Project 8 Ltd | Altrincham | 2023 |
| GPC Project 9 Ltd | Altrincham | 2023 |
| GPC SPV 1 Ltd | Altrincham | 2023 |
| GPC SPV 2 Ltd | Altrincham | 2023 |
| GPC SPV 4 Ltd | Altrincham | 2023 |
| GPL Specialist Ventilation Services Ltd | Sheffield | 2012 |
| GPS Renewables Limited | Glarryford | 2012 |
| GPV Rhynie Limited | Edinburgh | 2014 |
| GR Renewables 1 Limited | London | 2021 |
| GR Renewables 2 Limited | London | 2021 |
| GR Renewables 3 Limited | London | 2021 |
| GR Renewables 4 Limited | London | 2021 |
| GR Renewables 5 Limited | London | 2021 |
| GR5 Reseau GAZ Limited | London | 2014 |
| Gra-Conn Services Ltd | Sidcup | 2021 |
| Gracelands Complete Maintenance Services Limited | Cheshunt | 2003 |
| Graeme Richardson Limited | Paisley | 2018 |
| Grafton Underwood Solar Limited | London | 2018 |
| Graham Engineering and Facilities Services Ltd | London | 2026 |
| Graham for Electric Infrastructure Projects Ltd | Wembley | 2020 |
| Graham Price Electrical Limited | Milton Keynes | 2010 |
| Graig Fatha CE Turbine Ltd | Redruth | 2018 |
| Graig Isaf Hydro CYF | Llanbedr | 2018 |
| Grain LNG Limited | Rochester | 2002 |
| Grain North Power Limited | London | 2019 |
| Grainger Electrical Services Ltd | Sevenoaks | 2018 |
| Granada DC Power Limited | London | 2026 |
| Grand Solar Products Ltd | Bradford | 2021 |
| Grande Lago Holdco Limited | London | 2022 |
| Grandsam Investments Limited | London | 1999 |
| Grange Farm Energy Limited | Guildford | 2013 |
| Grange Farm Solar Limited | Kings Langley | 2012 |
| Grange Farm Solar Park Limited | Exeter | 2012 |
| Grange Farming (Barlings) Limited | Newark | 2010 |
| Grange Generation Limited | Worthing | 2016 |
| Grange Lane Bess Limited | London | 2025 |
| Grange Renewable Energy Limited | Kings Langley | 2011 |
| Grange Renewables Ltd | Cookstown | 2016 |
| Grange Solar Farm Limited | London | 2014 |
| Grange Solar Limited | Gatwick | 2011 |
| Grange Wind Farm Limited | London | 2007 |
| Grangemouth CHP Limited | Grangemouth | 1997 |
| Grangemouth Energy Company Limited | Lyndhurst | 2018 |
| Grant Airconditioning & Ventilation Limited | Newark | 2003 |
| Grantham Solar Farm Ltd | London | 2014 |
| Granville Energy Supply Limited | Dungannon | 2016 |
| Granville Road Solar Limited | Reading | 2015 |
| Grass Roots Renewables C.I.C. | Maghera | 2008 |
| Grasslands Solar Farm Limited | London | 2022 |
| Grastim UK Ltd | London | 2022 |
| Gravel Hill Farm Limited | Hull | 2011 |
| Graveley Bess Limited | London | 2025 |
| Gravelly Energy Storage Ltd | London | 2021 |
| Gravity Engines International Ltd | Callington | 2021 |
| Graylingwell Energy Services Limited | West Malling | 2010 |
| Grayside WF Ltd | Biggar | 2019 |
| Graythorp Energy Limited | Yarmouth | 2018 |
| GRC Hydro Limited | Brecon | 2012 |
| Greadon Power Ltd | Holsworthy | 2010 |
| Great County Energy Ltd | Birmingham | 2025 |
| Great Dunmow Power Limited | Salford Quays | 2023 |
| Great Gable Energy Limited | Edinburgh | 2015 |
| Great House Energy Centre Ltd | Rochford | 2015 |
| Great Oak Energy Ltd | London | 2026 |
| Great Oaks Renewable Energy Park Ltd | Chipping Norton | 2022 |
| Great Seabrook Solar Limited | Hove | 2012 |
| Great Wilbraham Solar Park Limited | London | 2013 |
| Greater Gabbard Offshore Winds Limited | Reading | 2003 |
| Greater Gabbard Ofto PLC | London | 2012 |
| Grebdlog Ltd | Lanark | 2024 |
| Green Air Renewables Ltd | East Boldon | 2012 |
| Green BIO Generation Limited | Belfast | 2016 |
| Green BIO Refinery Limited | Belfast | 2016 |
| Green Breeze Energy (Holdings) Ltd | Alloa | 2016 |
| Green Breeze Energy Ltd | Alloa | 2012 |
| Green Bulb Energy Birmingham Ltd | Birmingham | 2025 |
| Green Bulb Energy GMR Ltd | London | 2025 |
| Green Bulb Energy Ltd | Sandwich | 2024 |
| Green Carbon Chain Limited | Omagh | 2021 |
| Green Cedar Solar Limited | Rochdale | 2022 |
| Green City GAS Solutions Limited | London | 2017 |
| Green Compared Ltd | Romford | 2016 |
| Green Consult and Finance Ltd | Richmond | 2021 |
| Green Cool UK Ltd | Cardiff | 2014 |
| Green Create W2V Kent Ltd | London | 2018 |
| Green Current Energy Ltd | Antrim | 2025 |
| Green Dome Property Services Ltd | London | 2018 |
| Green Dragon Hydrogen Limited | Haslemere | 2022 |
| Green Earth Solar Farm Limited | London | 2024 |
| Green Eco Group Ltd | Waltham Abbey | 2022 |
| Green Eco Ltd | Pontefract | 2024 |
| Green Electricity Generation Limited | Norwich | 2011 |
| Green Empire Infrastructure Company Limited | London | 2026 |
| Green END Energy Centre Limited | Norwich | 2024 |
| Green END Renewables Limited | London | 2014 |
| Green Energy and Storage Systems Limited | London | 2023 |
| Green Energy Capital Advisors Limited | Sheffield | 2024 |
| Green Energy Connects Ltd | Ilford | 2025 |
| Green Energy Distributors Ltd | Lytham St Annes | 2025 |
| Green Energy Exim Ltd | Richmond | 2025 |