Pilot study tracks big returns for recycling braking energy and offering grid support
CARY, N.C. – ABB has released the results of a six-month pilot program of an innovative public transit energy storage system (ESS) designed to transform the Southeastern Pennsylvania Transit Authority (SEPTA) from an inefficient energy consumer into both a smart consumer and producer of energy.
Partnering with smart grid technology firm Viridity Energy and Saft Battery, ABB led the design, supply and integration of the “Wayside Energy Storage Project” within SEPTA‘s aging transit infrastructure. Originally installed in April 2012, the system captures braking energy for redistribution into the SEPTA power network while generating revenue with behind the meter load response to sustain the local grid and the wholesale energy market.
Results achieved to date show that the single substation system on the Market-Frankford Line in North Philadelphia generates over $250,000 of annual energy savings and earned revenues. The initiative supports SEPTA’s Sustainability Program goal of reducing energy intensity (energy use per passenger mile) by 10 percent by 2015.
“Recovering energy lost during braking is one of SEPTA’s primary energy-saving initiatives,” said Jacques Poulin, Product Manager of Energy Storage, ABB Rail Transportation. “Eventually, the industry-wide deployment of these smart grid technologies will deliver substantial economic and environmental benefit to public transit systems.”
The transit authorities are uniquely positioned to forever change their cost structure by harnessing regenerative braking. “Regenerative braking” captures the kinetic energy of the decelerating vehicle and converts it into electricity. ABB deployed the ENVILINE™ ESS which connects to the catenary or “third rail” of the train system to recover this otherwise wasted energy. In this project, the functionality of the ESS was expanded to feed the energy back to the trains, while additionally modulating the load of the substation as a revenue generating asset connected to the PJM network, the regional transmission organization (RTO) that coordinates the movement of wholesale electricity.
The groundbreaking initiative shows how SEPTA and other transit authorities
to can participate in two key energy markets: frequency regulation (helping PJM maintain desired grid frequency) and economic load response (reducing consumption during peak demand when prices are high).