Powering A City With Its Subways And Massive Spinning Wheels

Coming to a city near you soon: By adding giant flywheels to subway systems, cities are able to harness the power created by thousands of braking trains, using it to accelerate other trains or feeding it back into the grid. Every time a train starts and stops, it draws or dissipates several megawatts of energy, enough to power more than a thousand homes. This happens thousands of time per day, every day, in commuter rail systems across the country.

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Powering A City With Its Subways And Massive Spinning Wheels