South Western Railway completes trial of Class 159 emission reducing technology

SWR train
Credit: SWR

South Western Railway has confirmed it has completed a trial of new emission-reducing technology.

In partnership with Porterbrook and Eminox, South Western Railway has trialled a new system that has real-world reductions in pollution from nitrous oxides (NOx) by over 80% and hydrocarbons, carbon monoxide and particulate matter (PM) by over 90%.

The EMxS5 system by Eminox was fitted to the exhaust of a Class 159 train in full passenger use between London Waterloo and Exeter and is the first successful transfer of the technology into a rail environment.

The trial was funded by the Department for Transport through InnovateUK’s first of a kind funding. The trial was completed in March this year following six months of testing.

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.”

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.”

Mary Grant, CEO of Porterbrook, said: “As a rolling stock asset management business, Porterbrook takes seriously its responsibility to develop innovative ways of reducing emissions. We are particularly pleased to be able to do this by drawing on proven technologies from other sectors. Porterbrook believes by partnering with South Western Railway and automotive after-treatment specialists, Eminox, we can accelerate the delivery of cleaner and more environmentally friendly trains to Britain’s railways.”

Carlos Vicente, Retrofit and Aftermarket Sales Director for Eminox, said: “Here at Eminox we are wholly committed to using innovation and technology to improve air quality and tackle climate change. For more than 20 years we have developed cutting-edge retrofit technology, which has significantly reduced diesel exhaust emissions from public transport and commercial vehicles helping to improve air quality. We have worked in partnership with both South Western Railway and Porterbrook to adapt our technology for the rail sector. This ground-breaking trial demonstrates how it is possible to dramatically reduce rail emissions in a timely and cost-effective way.”

Neil Drury, Engineering Director for South Western Railway, 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.”

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  1. South Western Railway should still continue on refurbishing their Class 158, Class 159, Class 444 and Class 450 units with the new SWR livery. Along with the Class 701 being delivered and to enter service next year which is to replace the Class 455, Class 456, Class 458 and Class 707 (Class 707 cascaded to Southeastern).

  2. These test results are good; I understand a similar programme is being undertaken on a 170 dmu. If we cannot electrify the Uckfield line then reducing pollution from the Southern 171s will be a step in the right direction.


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