SOUTH Western Railway says it has completed a 'revolutionary trial of new technology' that will reduce harmful emissions from diesel trains by more than 90 per cent.

The company has been working with the company Poterbrook and emissions specialist Eminox on the new system, which cut pollution from nitrous oxides (NOx) by more than 80 per cent and hydrocarbons, carbon monoxide and particulate matter (PM) by more than 90 per cent.

Neil Drury, engineering director for South Western Railway (SWR), said: "We’re rising to the challenge of tackling climate change by developing innovative technology that minimises the impact of air pollution from diesels trains on passengers and the communities we serve.

"We’re serious about sustainability, and determined to use expertise and technology from inside and outside the industry to help clean-up older trains and deliver greener, cleaner journeys.”

The technology will be able to be fitted to existing trains, as a third of the UK's rolling stock remains powered by diesel engines.

Electrification and bi-mode trains provide more long-term environmentally friendly solutions, says SWR, but the new retrofitted tech can deliver immediate air quality benefits for passengers.

Rail Minister Chris Heaton-Harris said: " The success of this trial in reducing harmful emissions underlines the importance of the First of a Kind competition, which funds pioneering projects to support better, more environmentally friendly rail journeys.

“Reducing the railway’s environmental impact and supporting decarbonisation is a priority for this Government. Harnessing innovation like this will be crucial in making our railways greener and cleaner in the future.”

Meanwhile, Kelvin Davies, innovation lead - Rail at Innovate UK, said: “Working with the Department for Transport, Innovate UK has sought the best ideas from innovators to make our railway ever greener. Technology such as that developed by Eminox and deployed by Porterbrook and SWR delivers a win-win.

"Not only will people and the environment benefit from greatly-reduced emissions but also the commercial opportunities and export potential is clear too.”