The London Underground network is set to become even greener, as EDF Renewables UK, through its subsidiary Longfield Solar Energy Farm Limited, has been awarded a Power Purchase Agreement (PPA) to supply clean solar energy to Transport for London (TfL).
Construction work on the new solar farm in Longfield, Essex, is slated to begin next year. When completed, the facility is expected to provide 80 GWh of clean electricity to TfL annually, which is equivalent to powering over 29,000 homes. This initiative will not only supply green energy to the Tube but also contribute to decarbonising and increasing the capacity of the National Grid. The project is also set to improve local biodiversity and create new green jobs both directly and within the supply chain, bringing economic benefits to the wider region.
This announcement comes as TfL aims to source up to 70 per cent of its electricity from renewable sources through future PPAs, as part of its broader energy purchasing strategy to switch to a 100 per cent renewable electricity supply by 2030. The Mayor of London, Sadiq Khan, simultaneously launched a new climate finance taskforce, designed to unlock the £75 billion needed to achieve London’s ambitious target of net zero by 2030.
Under the 15-year PPA, the new solar facility in Longfield, Essex, will generate and deliver green electricity for the Tube. Approximately 20 per cent of its output, equating to about 80 Gigawatt hours (GWh) of electricity per year, or 1,200 GWh collectively over 15 years, will go to TfL. This amount of clean electricity could power the entire Tube network for a year, or run both the DLR and Tram network for 15 years. Construction is expected to commence in 2026, and once completed, the facility could contribute around 400 GWh per year to the national grid by the end of the decade. Over the 15-year contract duration, TfL anticipates saving over 28,000 tonnes of carbon in its operations, which is equivalent to 33,300 one-way trips between London and New York City. As London’s largest single consumer of electricity, using approximately 1.6TWh per annum, the contract also guarantees renewable power to TfL at a fixed price, protecting the organisation against market volatility and potential disruptions.
The approximately 400-hectare solar facility, for which EDF Renewables UK secured planning permission from the Department of State for Energy, Security and Net Zero in June 2023, will transform lower-quality farmland. The newly built facility will incorporate extensive tree and hedgerow planting, and allow for natural regeneration, enhancing the surrounding environment and attracting a greater variety of plant and animal species. It is expected to achieve a positive biodiversity net gain of 87.1 per cent, significantly exceeding the 10 per cent legal requirement under the Environment Act 2021, thereby supporting local biodiversity commitments. Looking after nature and protecting the environment are key criteria in TfL’s contracts, aligning with TfL’s broader goals to be greener, more sustainable, and well-adapted to climate change.
By leveraging TfL’s purchasing power, the PPA contributes to energy security and confidence, stimulating the renewable energy industry within Great Britain to generate energy from new purpose-built facilities and further decarbonise the central grid. This new partnership will also boost the wider UK economy by creating green jobs in construction and operation at the site, and generating local economic activity in the east and southeast of England. TfL’s entry into the PPA enables the wider development and construction of large-scale renewable assets, enhancing the security of the UK’s clean energy supply.
The energy required to power transport in London is equivalent to the electricity consumed by around 420,000 homes, accounting for 12 per cent of homes across the capital. TfL’s long-term Energy Purchasing Strategy aims to procure up to 70 per cent of its total electricity needs through PPAs, with the remainder primarily via a flexible green tariff. This will contribute to the wider ambition of using 100 per cent renewable electricity across TfL’s operations by 2030, supporting the Mayor’s goal for London to be a net zero carbon city by 2030.
This purchasing commitment coincides with the Mayor’s launch of a new climate finance taskforce, chaired by Dr. Rhian-Mari Thomas of the Green Finance Institute. Comprising investors and facilitators of investment in climate projects, the taskforce aims to unlock billions in long-term, flexible private finance.
Sadiq Khan, The Mayor of London, said: “London is already a world leader when it comes to addressing the climate crisis, so it’s only right that we continue blazing this trail when it comes to our transport system. This new agreement will enable us to power our transport network with clean, green, renewable energy and reduce TfL’s carbon emissions as we continue building a greener and better London for everyone.”
Lilli Matson, TfL’s Chief Safety, Health and Environment Officer, said: “As one of the largest electricity consumers in the UK, we are absolutely committed to doing what we can to decarbonise London through clean, renewable energy sources. This PPA is a landmark moment for us as this agreement enables EDF Renewables UK to invest in a brand new facility for clean electricity supply for our Tube network and GB’s grid – a significant step in our mission to make all our services powered this way by 2030 and a new green era for the Tube. We are using our purchasing power to make public transport the most environmentally sustainable choice Londoners can make. By giving EDFR the security to invest in new renewable energy sources in the UK, we are also creating new green jobs, improving the local biodiversity and wildlife, and stimulating the national economy. This will open doors to more public-private approaches to further accelerate the decarbonisation of GB’s grid.”
Matthieu Hue, CEO of EDF Renewables UK, said: “We are proud to partner with TfL on this PPA, which marks a significant step forward for the delivery of our Longfield solar farm. This agreement is built upon our shared commitment to sustainability and investing in clean energy, helping to power essential public services with low-carbon electricity and support the UK’s journey to net zero.”
Michael Shanks MP, Energy Minister, said: “Very welcome news to see TfL making huge strides to power its network with clean, homegrown energy – supporting local jobs whilst reducing their emissions. Getting more solar on the grid supports our clean energy mission and Plan for Change – ending our reliance on unstable fossil fuel markets, boosting our energy security, and bringing down bills for good.”
Rollo Maschietto, Interim Head of Power at the REA (Renewable Energy Association), said: “This is exactly the kind of leadership we need from major public bodies to unlock investment in clean energy infrastructure. TfL is helping to bring forward large-scale UK solar – the cheapest and quickest form of new electricity generation. The more solar we deploy, the lower bills will be and the less exposed we’ll be to volatile fossil fuel markets. This is a blueprint for how the public sector can get behind the energy transition while supporting green jobs and strengthening our energy security.”
Rachel Cary, Head of Industrial Strategy at Energy UK, said: “It’s great to see Energy UK member EDF partnering with Transport for London (TfL) to deliver locally sourced solar energy – a great example of how collaboration can help power London’s vital public transport network sustainably. As transport remains the UK’s highest-emitting sector, projects like this play a crucial role in cutting emissions while supporting local economic growth and creating green jobs. Power Purchase Agreements (PPAs) are a powerful tool to unlock investment in renewables. They help reduce system costs, improve air quality, and offer organisations like TfL long-term price stability – all while accelerating the transition to a cleaner, more secure energy system.”
TfL is also expanding its renewable energy portfolio by launching a tender for a delivery partner to collaboratively develop purpose-built solar farms connected directly to the London Underground network. In the long term, these private wire schemes could generate up to 64 megawatts (MW) of electricity for the network, approximately five per cent of the Tube network’s total electricity needs. The outcome of this tender will be announced once the process is complete.
