APC has demonstrated a fuel cell unit that fits into a standard data centre rack, aimed at displacing traditional diesel generators whose job is to supply backup power. The fuel cell is aimed at installations where environmental concerns outweigh cost. It could also be a pointer for future, greener data centres.

Slotted into a black box that fits visually into APC's InfraStruXure product line - its data centre cooling and management system - the fuel cell we saw demonstrated, for its first outing in the UK, puts out 30kW. A pair of racks stuffed with blade servers could approach this level of power consumption.

The system consists of three modules in the lower portion of the rack, with cooling units above for the inverters that convert the cells' native 192V DC to 240V AC. Attached to the fuel cell is a 15mm pipe from a pressurised hydrogen tank that sits outside the facility, which we saw installed at communications systems integrator Comtec Enterprises. The outlet, which penetrates the external wall, emits only water. When running, the system emits a moderately loud hum, but is quieter than a generator by several orders of magnitude.

APC's UK VP Paul Tyrer said that the system was built by APC in its Danish labs. The company launched the fuel cell on the occasion of Comtec's launch of its new data centre demo suite and 24/7 network operations centre.

Demonstrating the unit's capabilities, Comtec MD Nick Ewing said that, in the event of mains power failure, the fuel cell takes about 30-40 seconds to kick in, about the same as a standard generator. It then keeps the data centre's UPS batteries supplied until either mains is restored or the hydrogen runs out.

The main drawback right now is the cost of being an early adopter. Ewing said the system demonstrated would cost about £35,000-£40,000, a bill that would pay for a generator with ten times the output.

He said however that a data centre in an area such as central London's Belgravia would have no choice because of strict planning legislation, and because local residents would not tolerate the noise and smoke emitted by a diesel generator on the roof of a facility.

"Some customers want this kind of technology, and fuel cells are now a growing market, for example in the automotive business," said Tyrer. "We want to take a lead in the battery/power market, and we see demand globally for the technology. The UK for sure is an early adopter - we've already sold a couple in Europe too."

Ewing said: "Integrating a fuel-cell into the data centre is the futurology element of the demonstration, but in reality, it won’t be too long before we start hearing of more fuel-cell implementations in the UK." He said that expected the price to fall as volumes rise.

While the production of hydrogen usually involves burning fossil fuels, APC is keen to present fuel cells as green technology, as the only emission at the point of use is water. If in future, hydrogen can be made without the production of greenhouse gases, the fuel cell could come into its own.