Philadelphia Deploys Energy Storage Technology In Its Trains

I’m happy to report that my hometown of Philadelphia has recently implemented energy efficiency technology on the trains I ride virtually every time I go back.  The Southeastern Pennsylvania Transportation Authority (SEPTA), the nation’s sixth-largest public transportation system and the fifth-largest electricity user in the Philadelphia metro region, has cut a deal with Viridity Energy to install an advanced battery storage system to recapture and deploy power from the trains’ regenerative braking.

I’ve seen a variety of competitive energy storage concepts, designed to accomplish the same task, and I find it interesting that we’ve wound up, at least for now, with batteries. Notably, it appears that flywheels make sense in this environment; the angular momentum that makes them impractical in vehicles with low turning radiuses is not a significant factor on trains.

In any case, go Philadelphia!