Arriva Group’s Chiltern Railways brings innovative emission-cutting train into service

Arriva Group’s Chiltern Railways train operating company is launching a new innovative train this week (w/c 7 February) which will significantly cut CO2 emissions, save fuel and reduce noise and air pollution, particularly around stations.

The train is known as 'HybridFLEX’ and is the result of a four-year partnership between Chiltern Railways, Porterbrook (the train owner) and the industrial technology giant, Rolls- Royce.  The companies worked together to convert a diesel train into one that now runs on both diesel and battery power.  The concept train is the first 100mph capable battery-diesel hybrid train to operate on the UK’s national rail network.

The train has been retrofitted with a Roll-Royce powerpack which means quieter and quicker journeys and a 25 percent reduction in CO2 emissions on every journey it makes. Nitrogen oxide and pollutants are also cut by 70 and 90 per cent respectively. The HybridFlex train substantially cuts fuel usage and reduces noise by up to 75 per cent in and around stations and urban areas. It also presents the opportunity for faster customer journeys in the future because the train will be able to accelerate away from a station more quickly.  

Arriva Group’s Managing Director for UK Trains, David Brown, commented: “Innovating for a sustainable future is at the heart of Arriva’s business and we’re incredibly proud of what has been achieved alongside Porterbrook and Rolls-Royce through a shared commitment to green technologies.  This ground-breaking concept-train will allow us to deliver cleaner, more sustainable rail services right now, further contributing to decarbonisation.”

Richard Allan, Chiltern Railway’s Managing Director, added: “Chiltern Railways is determined to operate a railway that is as sustainable and environmentally friendly as possible.

“We have worked hard with our partners to fit a powerful battery power pack underneath a 20-year old diesel train to make the train cleaner, quieter and quicker.

“We are really proud that this train is now carrying customers and look forward to assessing its performance in daily service.”

The HybridFlex train will initially operate between Aylesbury and London Marylebone with plans to bring the new type of train to the London to Oxford via Bicester Village route in the coming months.

Rolls-Royce’s ‘mtu‘ Hybrid PowerPack pairs a diesel engine with an electric unit that can function both as a motor and as a generator. The battery system stores power that is recovered during train braking.

The concept train will be assessed in customer service to understand if there is an opportunity to convert more diesel trains to use this innovative hybrid technology in the future.