| Follow Us: Facebook Twitter RSS Feed

In The News

Viridity, on the fast track to green transit, partners up for SEPTA project

Viridity Energy partners with Saft and Envitech on the first trackside energy storage system in North America, recycling energy from braking SEPTA trains and trolleys, according to the New York Times.

Subway trains need a lot of electricity to get going, turning electricity into kinetic energy, the energy of movement. When they pull into a station, many of them can do the opposite: generate electricity from their momentum. They turn their motors into generators to slow the train, producing current.

But in many systems, some of that energy goes to waste because of a bottleneck: the third rail, which carries current to the train, cannot handle as much energy as the train is generating during deceleration. Too much current pushes up the voltage, and when the voltage gets too high, the electricity is dissipated by running it through a piece of metal that converts it into heat.

But in Philadelphia, on the Market-Frankford line of the Southeast Pennsylvania Transit Authority, a new company called Viridity Energy will install batteries to capture a lot of that electricity and hold it while the train is in the station. Then it can deliver the power when the train starts up again or store it for a time of day when it is needed more.

Source: The New York Times
Read the full story here.
Signup for Email Alerts
Signup for Email Alerts