Uninterruptible power supplies (UPS) from MGE UPS Systems Inc., Costa Mesa, Calif. (www.mgeups.com/us), can now be fitted with something new: Fuel-cell modules from Ballard Power Systems, Burnaby, B.C. (www.ballard.com). The new rack systems, dubbed Pulsar EX RT, target high-density IT applications and servers.

The fuelcell UPS provide backup times of 4 to 24 hr or more as long as hydrogen fuel is available. Hydrogen in replaceable containers pipes directly to the fuelcell module. Like a battery, the fuel-cell module produces dc voltage that is then bused to the UPS.

Installed in an industry standard 19-in. rack, the fuel-cell power modules include electrical connections, N+1 redundancy capability, and various safety features. The 1-kW fuel-cell modules operate in parallel for power levels up to 50 kW. Three 85-lb fuel-cell modules are used in the UPS configuration.

MGE says scalable fuel-cell modules are particularly suitable for UPS and telecommunication markets. Batteries are problematic in these areas because of inadequate run times, excess weight, and a need for a lot of floor-space when backup times exceed 1 hr.