Researchers make breakthrough on storing energy for fuel cells4/2/2013
CALGARY - Researchers at the University of Calgary say they've made a breakthrough that could make renewable energy much more practical and affordable.
Their paper published in the journal Science says they've found a much easier and cheaper way to build an electrolyzer, which uses electricity to break up water into hydrogen and oxygen, the basic requirements of fuel cells.
Fuel cells take those gases and generate energy by recombining them. Water is the only waste product. The cells are seen as a possible source of clean, reliable power that could be built on almost any scale required.
Electrolyzers depend on rare, difficult-to-work-with and sometimes toxic metals, but the method developed by Curtis Berlinguette and Simon Trudel uses metals as common as rust.
It delivers results comparable to current techniques but costs about 1,000 times less.
That could make it easier to use hydrogen to store intermittent energy produced by renewable sources such as wind or solar generators — cheaper, more efficient and with fewer toxic materials than the batteries currently used.
"We're pretty excited about this," said Berlinguette.
A major problem, until now, has been producing the needed oxygen and hydrogen in electrolyzers. Current methods depend on the use of expensive rare earth metals in precise crystalline arrangements to catalyze, or speed up, the reaction.
Berlinguette and Trudel found a way to build catalyzers out of common metals without the need for the crystal structure.
The implications are potentially enormous.
One of the problems with renewable energy is that it's not necessarily generated when it's needed, but whenever the wind blows, the sun shines or the tide turns.
"If you think of a wind turbine producing electricity at two o'clock in the morning, there's no one around to actually use that electricity, so it just gets dumped," said Berlinguette. "If you could set that up with an electrolyzer, you could convert that electricity into hydrogen, then the next day, when there is demand, you can sell that electricity at a premium during periods of high demand."
Hydrogen energy storage could also replace bulky, inefficient, expensive and often toxic batteries.
"Wherever you can conceptually think of a battery having use, that's really where hydrogen comes into play."
Berlinguette envisions isolated northern communities powering themselves through fuel cells instead of diesel. Households could run off a system about the size of a beer fridge.
Fuel cells could even make conventional fossil-fuel-fired generators more efficient by allowing them to run at a constant pace regardless of demand. Excess power could be diverted to an electrolyzer and the hydrogen stored until needed.
"The nice thing about electrolytically produced hydrogen is that they can scale to the consumer," Berlinguette said.
Electrolyzers are between 70 and 90 per cent efficient at converting electricity into hydrogen and oxygen.
Berlinguette and Trudel have already formed a company called FireWater Fuel Corp. to market their work and expect to have a commercially available electrolyzer by next year.
Berlinguette estimates there's already a $250-million global market for electrolyzers.
Note to readers: This is a corrected story. An earlier version named one of the researchers as
(The Canadian Press)