South West Trains to equip 200 trains for regenerative braking
Britain's biggest commuter rail franchise is investing £2.2 million in a major regenerative braking project.
More than 200 trains on the South West Trains network, which covers south-west England running out of London Waterloo, will be fitted with the energy-saving technology.
Energy produced by a standard train braking is currently lost, but the regenerative braking system returns electricity to the third-rail system used on that part of the network, allowing trains in close proximity to draw on the electrical supply.
The initiative when fully implemented is conservatively expected to save 15 million kWh of electricity a year, enough to power more than 3,500 UK homes (based on Government figures putting mean annual domestic electricity consumption at 4,200kWh per household).
The first two trains, part of the Class 458 fleet, are now starting to test the technology in passenger service on the London Waterloo-Guildford and London Waterloo-Reading routes.
The whole fleet of 30 Class 458 (Juniper) electric multiple units is expected to be fitted with the regenerative braking software by the end of May 2010. The system will then be rolled out to SWT's 172 Desiro trains.
South West Trains engineering director Christian Roth said: "The roll-out of the regenerative braking system will deliver a significant step-forward in the environmental performance of our trains. We estimate that our energy consumption on the Suburban network, where the first trials are taking place, will be reduced by up to 8 per cent. As well as the obvious cost-saving benefits, we are also ensuring that energy previously lost is being put to good use by recycling it and helping to power other trains."
The regenerative braking project, which is being carried out in partnership with Network Rail and rolling stock providers Alstom and Siemens, is part of a major £11 million investment across SWT's parent Stagecoach Group as part of its new sustainability strategy.
South West Trains has a total of 334 trains in its fleet. The regenerative braking system is being fitted to all of the company's modern trains - the Class 458s and the Desiros - which covers a total of 202 trains or 60 per cent of the fleet. Of the rest, 41 are diesel-powered rather than electric. The remainder, the Class 455s, were designed around 35 years ago and are not compatible with regenerative braking systems in their current form without expensive adaptation.