Subways could soon be a source of energy

Subway systems consume enormous amounts of energy. To further complicate things, they usually require energy in short, intense jolts. 

For example, to get a ten-car subway train moving from a standing start might require a 30-second charge of three to four megawatts. Now, a company says they’ve come up with a new technology to harvest the wasted energy consumed by these systems.

Vycon Energy, a California-based company that specializes in energy storage systems, says that their advanced industrial flywheel technology could help subway and light rail systems save energy and money while also smoothing out the surges in the grid caused by these systems.

According to sources, the technology works on the same principal as regenerative braking — the system used in many electric vehicles. 

When the trains slow down, that energy is captured and stored by one of Vycon’s flywheels. A decelerating train can generate four MW of electricity. That energy could be used to get the train moving again.

The flywheels are not located in the trains, but at the station. Trains would send the energy to the bank of flywheels via a third rail system.

Vycon says they are also developing systems that will combine the flywheel technology with batteries for extended delivery of power.

Steve Duda, EarthTechling