Transport for London (TfL) has signed a landmark agreement with EDF Renewables UK to power the London Underground with solar energy, marking a major step in the capital’s transition to a net-zero transport system by 2030.
The 15-year Power Purchase Agreement (PPA) will supply TfL with around 80 gigawatt hours (GWh) of clean electricity annually—enough to power the entire Tube network for a year or more than 29,000 homes. The energy will come from a new solar farm to be built near Chelmsford, Essex, by EDF’s subsidiary, Longfield Solar Energy Farm Limited.
Construction of the 400-hectare facility is scheduled to begin in 2026, with full operations expected before the end of the decade. Once operational, Longfield Solar is set to deliver 400 GWh of electricity annually to the grid, with TfL receiving a fifth of its output.
As the UK’s largest single electricity consumer—using 1.6 terawatt hours annually—TfL is aiming to source up to 70 per cent of its power through direct agreements like this one, insulating itself from volatile energy prices while supporting renewable energy development.
“This deal marks the beginning of a new green era for the Tube,” said Lilli Matson, TfL’s Chief Safety, Health and Environment Officer. “We are using our purchasing power to make public transport the most environmentally sustainable choice Londoners can make.”
The solar farm is also set to deliver environmental benefits beyond energy production. EDF Renewables says the site will offer a biodiversity net gain of over 87 per cent—eight times the legal requirement—through tree and hedgerow planting, rewilding, and wildlife corridors.
EDF Renewables CEO Matthieu Hue described the deal as a “significant step forward” in decarbonising essential public services, while also creating green jobs and enhancing UK energy security.
The initiative was welcomed by political leaders and climate advocates. Energy Minister Michael Shanks MP praised the project for supporting “local jobs whilst reducing emissions”, while Mayor of London Sadiq Khan said it shows London is “leading the way in climate action.”
TfL has also launched a tender to find a partner to deliver further purpose-built solar farms, aiming to generate an additional 64 megawatts of electricity—around five per cent of the Tube’s annual needs—via direct private wire connections.
The announcement coincides with the launch of a new climate finance taskforce, aimed at unlocking £75 billion in private investment to help London reach its net zero target by 2030.
Industry experts called the partnership a blueprint for public sector decarbonisation. Rachel Cary of Energy UK said it shows how “collaboration can help power London’s public transport network sustainably,” while Rollo Maschietto of the Renewable Energy Association said the deal supports green jobs and energy resilience.
With this agreement and future renewable projects in the pipeline, TfL is positioning itself as a national leader in sustainable public infrastructure.
