Fraunhofer Institute for Transport and Infrastructure Systems (IVI) in Germany has developed a fuel cell-flywheel hybrid trolley (tram). The fuel cell-based system is a derivative of an earlier diesel-powered hybrid version.
The two-car hydrogen AutoTram is powered by a 80kW Ballard fuel cell system and three electric motors. Roof-mounted tanks hold 10 kg of compressed hydrogen at 200 bar (2,900 psi).
The tram uses a 325 kW flywheel from CCM with a capacity of 4 kWh for energy storage, recharged through regenerative braking, power from the fuel cell or a quick plug-in at a station.
(Earlier post on flywheel hybrids here.)
With a top speed of 60km/h, the tram is optically guided and runs trackless.