| ELM Solar Farms Ltd | London | 2023 |
| ELM Wind Farms Limited | London | 2013 |
| Elmec Installations Limited | Walsall | 2007 |
| Elmley Road Renewables Limited | Shepton Mallet | 2025 |
| Elms ISG Solar Limited | Cheltenham | 2020 |
| Elmya Energy UK 1 Limited | London | 2022 |
| Elmya Energy UK 17 Limited | London | 2022 |
| Elmya RPC UK Braybrooke Limited | London | 2022 |
| Elmya RPC UK Dover Limited | London | 2022 |
| Elmya RPC UK Grange Road Limited | London | 2022 |
| Elmya RPC UK Hunterston Limited | London | 2022 |
| Elmya RPC UK Melbourne Limited | London | 2022 |
| Elmya RPC UK Morningside Limited | London | 2022 |
| Elmya RPC UK Rednal Limited | London | 2022 |
| Elmya RPC UK Wadbrook Limited | London | 2022 |
| Elnath Solar Ltd | Bristol | 2020 |
| ELP Holdco Limited | London | 2025 |
| ELP Project CO2 Limited | London | 2025 |
| ELP Project CO3 Limited | London | 2025 |
| ELP PROJECTCO1 Limited | London | 2025 |
| Elslack Developments Ltd. | London | 2012 |
| Elstree Battery Storage Limited | London | 2024 |
| Elstree Flexpower Ltd | Cheltenham | 2016 |
| Elvanfoot Energy Storage 2 Limited | Motherwell | 2022 |
| Elvanfoot Energy Storage 3 Limited | Motherwell | 2022 |
| Elvanfoot Energy Storage Limited | Motherwell | 2020 |
| Elwy Clean Energy Limited | London | 2022 |
| Elyos Energy UK Ltd | Kings Langley | 2023 |
| EM Electrical Installation Ltd. | Leigh-On-Sea | 2014 |
| Emakare Electric Power Ltd | London | 2023 |
| Emakare Flaregas Ltd | London | 2023 |
| Emakare Ltd | London | 2022 |
| Ember Power Ltd | Belfast | 2013 |
| Embers Heating Solutions Ltd | London | 2024 |
| Emberton Solar Park Limited | London | 2013 |
| Emboe Energy Ltd. | Cookstown | 2017 |
| EMC2 Energy Ltd | Albourne | 2025 |
| Emce Solar Solutions Ltd | Scarborough | 2011 |
| Emdair Limited | Hastings | 1984 |
| EME Power Connections Limited | Sleaford | 2011 |
| EME Power Systems Limited | Sleaford | 2003 |
| Emea Energy Ventures Management Limited | London | 2006 |
| Emerald Green Power Ltd | London | 2021 |
| Emerald Holdco Limited | Buntingford | 2019 |
| Emerald Isle Solar Energy Limited | London | 2013 |
| Emerald Solar Energy Ltd | Solihull | 2024 |
| Emerald Solar Ltd | Solihull | 2026 |
| Emergent Energy PCC Ltd | Leeds | 2026 |
| Emergent Energy Systems Ltd | London | 2016 |
| Emerging Markets Power (Holdings) Limited | Belfast | 2016 |
| Emerging Markets Power (NI) Limited | Belfast | 2016 |
| Emik Sunny Days Ltd | Dunmow | 2020 |
| Emile Electrical Limited | Nelson | 2018 |
| Eminent Electrical Ltd | Harrow | 2024 |
| EML Electrical Contractors Limited | Peterborough | 2022 |
| EMO Electrical Limited | Glasgow | 2017 |
| Emotion Energy Solar One Limited | Glasgow | 2012 |
| Emotorparts Limited | Leicester | 2013 |
| Empire Air Conditioning Services Limited | Nottingham | 2022 |
| Empower Generation Ltd | Holywood | 2011 |
| Empower Renewables Limited | Greenside Place | 2020 |
| Empower Renewables Management Limited | Belfast | 2023 |
| Empoweru Limited | Cardiff | 2018 |
| EMS Incorporated Limited | Luton | 2026 |
| EMS Metering Ltd | Sunderland | 2021 |
| EMS Technical Services Limited | Hereford | 2012 |
| Emstream Limited | Walton-On-Thames | 2018 |
| Enbw UK Limited | London | 2021 |
| Enbw UK Renewables Limited | London | 2024 |
| Encapture Limited | Deeside | 2011 |
| Encompass Connections Limited | Knutsford | 2022 |
| Encompass Electricity Limited | Knutsford | 2021 |
| Encompass GAS Limited | Knutsford | 2021 |
| Encon Air Systems Limited | Moultonpark Industrial Estate | 1986 |
| Encyclis Earls Gate Holdco Limited | London | 2018 |
| Encyclis Europe Investments Limited | London | 2017 |
| Encyclis Ireland Assets Limited | London | 2017 |
| Encyclis Limited | London | 2006 |
| Encyclis Newhurst Holdco Limited | London | 2019 |
| Encyclis Protos Holdco Limited | London | 2019 |
| Encyclis Rookery Holdco Limited | London | 2018 |
| Encyclis UK Investments Limited | London | 2018 |
| Enderby Battery Storage Limited | London | 2019 |
| Enderby Bess Limited | Cheltenham | 2022 |
| Enderby Energy Limited | London | 2023 |
| Enderby Storage Limited | London | 2017 |
| Endine Solar Limited | London | 2022 |
| Endip International Development Ltd | London | 2012 |
| Endorpha Ltd | Ballyclare | 2022 |
| Endura GAS Limited | Bideford | 2015 |
| ENE Electrical Services Ltd | Wirral | 2014 |
| Eneco 365 Limited | Leeds | 2013 |
| Eneco Burn of Whilk Limited | Leeds | 2013 |
| Eneco MOY Limited | Leeds | 2010 |
| Eneco Oaklands Limited | Leeds | 2013 |
| Eneco Sevor Limited | Leeds | 2011 |
| Enel X UK Limited | London | 2009 |
| Enerdex Ltd | Scarborough | 2025 |
| Enerdom Limited | Lichfield | 2012 |
| Energ Electrical Services Limited | Ashford | 2023 |