Hydrogen trains in the UK could be a reality sooner rather than later after train giant Alstom confirmed its plans to introduce the technology in the UK.

The pledge by the French firm comes in response to the UK government’s desire to phase out diesel trains in favour of hydrogen by 2040, which means nearly a third of the trains in the country will need to be replaced or refurbished. Alstom has announced it is working with Eversholt Rail to convert Class 321 electric trains to hydrogen.

The proposed move to hydrogen comes in the wake of growing concerns about pollution from diesel emissions at railway stations. The Rail Safety and Standards Board is currently studying concentrations of toxic nitrogen dioxide and particulates at London's King's Cross and Edinburgh's Waverley stations in a bid to understand the scale of the issue.

Rail minister Jo Johnson in February revealed government’s ambition for all the UK's 3,900 diesel trains to be scrapped by 2040. Johnson called on Britain to be “more environmentally ambitious” because increased travel has resulted in greater carbon emissions.

The new hydrogen fleet could even be on the network within three years with Alstom saying trains operating will be almost silent and with the same range and speed as traditional diesel and electric trains.

Commenting on the prospect of hydrogen trains in the UK, Nick Crossfield, managing director of Alstom UK and Ireland, said: “Not only are hydrogen trains zero carbon, they are near-silent and emit no particulates, which means they offer substantial air quality and noise pollution benefits too. On cost, hydrogen trains can help to avoid the necessity for line electrification, which represents a significant investment for customers.”

On April 30, during a transport select committee evidence session, the rail minister told MPs that a hydrogen train was on trial in the Lake District with trains being trialled in Germany, where Johnson said he would be visiting.

“We think the potential long-term application of hydrogen in the UK is very significant,” Crossfield added. “Less than 50% of the UK network is electrified, and much that isn’t electrified is unlikely ever to be so. Starting with this conversion, we think hydrogen could offer the right zero carbon solution for many parts of the network.”