Using subways as an energy source
PHILADELPHIA, PENNSYLVANIA - Subway trains in Philadelphia may soon help generate electricity using new braking systems and a smart-grid technology.
The Southeastern Pennsylvania Transportation Authority is piloting the system that converts kinetic energy into electricity as the train slows down. A battery installed at a substation will store electricity to help power the subways.
Experts said the system could generate extra power that could be sold back to the regional power grid, according to MIT Technology Review.
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