German methanol unit wins Pentagon portable-power prize
Fuel-cell/battery combos sweep the rankings
The US defence department has announced the winner of its "Wearable Power Prize", a contest to develop a portable powerpack which could lessen the crippling load of batteries carried by modern soldiers. The $1m purse has been taken by US firm DuPont, partnered with Germany's SFC (Smart Fuel Cell).
The prize, inaugurated last year, initially attracted 169 competing teams. These were whittled down to twenty in preliminary testing. All the entries had to weigh less than 4kg, be suitable for attachment to a soldier's combat webbing, and offer energy density better than any available battery technology.
The surviving 20 contenders went forward to the semi-finals, a 92-hour bench test discharging 1,840 watt-hours of juice (20 watts output over time). Just six powerpacks made it through this test without running flat.
These six then went into the final event without being recharged. They faced a four-hour series of "field tests", with the systems worn by a team member and dispensing a further 80 watt-hours to power real equipment in typical military applications. These included running a laptop, a Land Warrior wearable-smartphone rig, a thermal scope, heated and cooled garments, a water purifier and an inflation pump.
Those which got through the final were then ranked by weight, with DuPont/SFC's "M-25" system coming in first at 3.76kg. The M-25 used a methanol fuel cell, hybridised with a battery pack to store the cell's output for better peak-load performance. Overall it held almost two kilowatt-hours.
Second and third places, winning a half-million and a quarter-million dollars, went to Adaptive Materials Inc (AMI)'s "Amie25" and Capitol Connections' "Jenny 600S". Both these systems - like all those which reached the final - used hybridised fuel cells too, though of different types to the winning M-25.
The winning methanol powerpack weighs a fifth what an equivalent amount of military batteries would, and its fuel is easily stored and handled in a military context. With a modern foot soldier's mission endurance typically limited much more by batteries than by food or ammunition, the technology would seem to have a bright future. Safety and heating concerns which have long delayed commercial applications will probably not be so much of a barrier in the military: soldiers who routinely carry grenades, demolition charges and even portable missiles will not find a methanol powerpack unacceptably hazardous.
"Fuel cells are the portable and off-grid power sources of the future," said Peter Podesser, CEO of SFC Smart Fuel Cell. ®