Sunlight is one of the most promising sources of untapped energy. And, it is clean and seemingly limitless. However, the cost per watt of power generated from sunlight is five to 10 times more expensive compared to fossil fuels.
Part of the added cost is attributed to difficulties in storing energy collected from the sun so that it can be used at night, when there is no sunlight. The fuel cell holds promise in solving this problem.
At its core, a fuel cell requires hydrogen and oxygen to generate electricity with water as the only byproduct.
An electrolyzer conducts this reaction in reverse, with energy being used to revert water to hydrogen and oxygen.
The UC Riverside students' research focuses on combining the fuel cell and electrolyzer into what they call a regenerative hydroxide exchange membrane fuel cell system.
The electrolyzer splits water to generate hydrogen and the fuel cell generate power using the hydrogen. The water byproduct created by the fuel cell is spit back in the electrolyzer and the process starts again.
The key innovation is a newly developed quaternary phosphonium-based hydroxide exchange membrane that allows use of catalysts such as nickel or silver, which are thousands of times less expensive than platinum, a catalyst now commonly used.
By combining the membrane with a fuel cell/electrolyzer set up, a commercial prototype may only be a few years away. The students are now working on developing a prototype.
"This is not your normal fuel cell," Yan said. "This is really a new breed."
|Contact: Sean Nealon|
University of California - Riverside