A ground-breaking project in Philadelphia is capturing energy from trains and sending it to the grid.
The Southeastern Pennsylvania Transportation Authority (SEPTA) is doing a pilot project on one of its train lines that captures the regenerative energy from braking trains, stores it in megawatt-scale batteries and then sends it to the regional grid.
Besides providing significant energy savings it will be a new source of revenue for SEPTA.
When SEPTA's trains brake at each stop to load and unload thousands of Pennsylvania passengers, the kinetic energy of the train is converted into electricity.
But without a method to capture that excess electricity, it can't be stored and used later.
The new technology demonstrates a first-in-the-world achievement for public transit, and showcases the potential of the smart grid, they say.
SEPTA is working with Viridity Energy, a smart grid technology firm that specializes in electric market integration, and Saft is designing and manufacturing the batteries. Envitech Energy, owned by ABB, is providing power controls, power conversion and system integration.
Viridity Energy's VPower optimizer enables simultaneous regenerative capture, regulation performance, and energy market participation by selecting which market to participate in based upon market pricing, battery state of charge, and availability of regenerative energy from the trains.
The pilot is partially funded through a 2010 Pennsylvania Energy Development Authority grant program and through Ben Franklin Technology Partners.