Network Rail, the operator of Britain's railway infrastructure, has entered into a 10-year deal with the French-owned EDF Energy to provide low-carbon electricity to the railways.
Under the £3bn ($4.8bn, €3.6bn) contract, EDF will supply around 3.2 terrawatt hours of energy per year to the railway network for the next decade. EDF will provide low-carbon energy generated from its eight nuclear power stations.
"The deal places nuclear energy at the heart of the UK's infrastructure for the next 10 years and serves to underline that nuclear power is part of everyday life in Britain," Vincent de Rivaz, CEO of EDF Energy, said in a statement.
The supplied electricity will primarily be used to power electric trains, which accounts for 55 percent of the traffic. Network Rail is looking to electrify more than 2,000 track miles across Britain over the coming years.
The main electrification schemes include the Great Western Main Line, Liverpool to Manchester and the line from Southampton docks to the West Midlands and Yorkshire.
Following the completion of the schemes, which are part of Network Rail's major expansion plan for the 2014-19 funding period, 75 percent of Britain's rail traffic will be electric-powered.
Network Rail earlier proposed a £37.5bn strategic business plan to operate and expand Britain's railway over five years to 2019.
"Rail is already the greenest form of public transport and this partnership with EDF Energy will help us make it greener still. Our work to electrify hundreds of miles of railway represents the biggest programme of rail electrification in a generation and will provide faster, quieter and more reliable journeys for millions of passengers every week while cutting the cost of the railway," said David Higgins, Network Rail chief executive.
Network Rail is the single biggest consumer of electricity in Britain. It uses electricity for more than 20,000 miles of railway, tens of thousands of signals and hundreds of signal boxes controlling 25,000 trains a day.
By 2020, 54 percent of Britain's rail network will be electrified, compared to the 40 percent at present. Electric trains are considered as more environment-friendly than their diesel counterparts.
EDF Energy has already won supply contracts for the UK Government, including the National Health Service, Highways Agency and the Metropolitan Police, in addition to a deal agreed last year to provide electricity to the majority of Scotland's public bodies.