Transport for London has announced a plan to make its tube train system even more efficient by recycling braking energy.

The plan is to harvest wasted braking energy from Victoria line trains. Captured energy could be enough to power the entire Holborn station for more than two days a week.

The London Underground has already tested the inverter system for a five-week trail. The results show that a saving of as much as £6million every year could be made. This is on top of the reduced carbon footprint of the service.

On top of that the system also means less heat produced from the brakes of trains. This means cooler stations without the need to spend as much on artificially cooling them. The saving equates to 1MWh per day which is real terms is enough to power 104 average homes per year.

This trial comes as a part of a wider system put in place by the Mayor to make the Tube greener. Greenwich Power Station will also be remodeled to convert it into a low-carbon power generator that will juice-up the Tube network. This will use six gas engines to replace boilers with waste heat being channeled into a new local heat network for residents.

Matthew Pencharz, deputy mayor for environment and energy, said: "The results of this project are really exciting and show huge potential for harnessing some of the immense energy in our Tube trains. The trial puts London at the cutting edge of this kind of technology and clearly demonstrates how energy from trains can be recovered to power Tube stations, making the network more environmentally friendly and cost effective."

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