In what LU claims is a world-first, an inverter system was installed at the Cloudesley Road substation for a five-week trial. According to LU, the reclaimed waste energy from Tube train brakes over a one-week period was enough to power Holborn station for two days. The technology has the potential to capture 1 Megawatt hour (MWh) per day – enough to power over 100 homes for a year.
“This…regenerative braking system has the potential to transform how we power stations across the TfL network, unlocking massive power savings and significantly reducing our energy bills,” said Chris Tong, LU’s head of Power and Cooling.
“We are committed to doing more to reduce our energy use, and this technology - a world first for metro railways - is one of a number of innovations we’re embracing to lower our environmental impact.”
As well as recycling energy, the system also reduces the amount of heat generated by trains when braking. This means less cooling is required in London Underground’s tunnel network, enabling increased energy efficiency. Overall potential savings are estimated to be in the region of £6m per year.
“The results of this project are really exciting and show huge potential for harnessing some of the immense energy in our Tube trains,” said Matthew Pencharz, Deputy Mayor for Environment and Energy
“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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