UA prof’s research could advance fuel cell technology
Breakthrough could boost hydrogen vehicle program
Dusty Compton
By Wayne Grayson Staff Writer
Published: Friday, March 18, 2011 at 3:30 a.m.
Last Modified: Friday, March 18, 2011 at 1:34 a.m.
Last Modified: Friday, March 18, 2011 at 1:34 a.m.
University of Alabama professor David Dixon, a hydrogen fuel cell researcher, is shown in his lab at Shelby Hall on the UA campus.
Published: Friday, March 18, 2011 at 3:30 a.m.
Last Modified: Friday, March 18, 2011 at 1:34 a.m.
Last Modified: Friday, March 18, 2011 at 1:34 a.m.
TUSCALOOSA | Because of support for electric cars from the current presidential administration and competition between automakers to bring more such cars to market, hydrogen fuel cell technology has fallen far behind electricity in the minds of most Americans as a feasible replacement for gasoline.
But a University of Alabama professor’s recent findings could bring hydrogen back into the discussion.
In a paper published in this week’s Science magazine, researchers from Los Alamos National Laboratory and UA chemistry professor David Dixon detail a process for recycling ammonia borane, a material used to store hydrogen in fuel cell vehicles.
After former President George W. Bush focused heavily on hydrogen fuel cell research in his State of the Union Address in 2003, ammonia borane quickly became a popular choice among researchers as the safest way of storing hydrogen inside a vehicle, Dixon said.
To create ammonia borane, hydrogen must be produced first. This is done by mixing natural gas or oil with water at a high temperature, Dixon said. The hydrogen is then combined with boron and nitrogen compounds to form ammonia borane, a colorless solid material, he said.
In a vehicle equipped with a hydrogen fuel cell, think of that block of ammonia borane as the gas tank. The hydrogen inside the ammonia borane stays put until the vehicle heats it up. Once the ammonia borane is heated, the hydrogen flows from it into the vehicle’s fuel cell, which powers the vehicle by combining the hydrogen with oxygen to produce electricity.
Once hydrogen leaves ammonia borane, the rest of the block stays behind as waste.
“Which is very different from a regular car, where gasoline simply leaves the tank and leaves nothing behind,” Dixon said. “There is still waste from gasoline, but that waste is let out into the environment as exhaust. With this fuel cell vehicle, we don’t let any of the waste into the environment.”
For years, researchers have been trying to find a more cost-efficient way of taking the ammonia borane waste from a vehicle and recycling it by regenerating hydrogen within it. Dixon said hydrogen is regenerated within that waste by combining it with the compound hydrazine.
Until now, that process has been so expensive it has hurt hydrogen’s economic feasibility in powering the nation’s cars. In the newly released findings, Dixon and his colleagues say that they have made the process of recycling ammonia borane much cheaper.
“In the past, doing this was a complicated and expensive process that involved a lot of mass being moved around a plant,” he said. “But we’ve simplified the process to two reactors. The hydrazine is made in one, and in the other it’s combined with the ammonia borane waste.”
Progress toward these findings has been hampered since President Barack Obama took office.
In 2009, Obama’s Energy Secretary Steven Chu proposed $100 million in cuts to hydrogen fuel cell research and announced a massive shift in the type of research the Department of Energy would pay for. Hydrogen-powered cars were not on the list.
Chu’s proposed cuts did not make it into the final 2010 budget, but on Monday the Energy Department released its proposed fiscal 2012 budget, which increases funding for solar, wind, geothermal and battery technologies but again seeks to cut the hydrogen program’s funding — this time by $70 million, which would be about
40 percent of the program’s 2010 budget allocation.
Since Obama took office, federal funding for hydrogen research at UA’s Center for Advanced Vehicle Technology has dried up. Dixon’s latest findings were funded by the final year of available funding.
Nevertheless, Dixon said he hopes he and his colleagues’ recent findings change the government’s mind about hydrogen.
But what do these findings mean for fuel cell vehicle owners of the future? Dixon said the process of refueling could look very similar to how it does today.
“The first way would be pulling up to a service station and popping off a bolted-on container of ammonia borane in back and popping a new one in,” Dixon said. “But we’re also trying to make ammonium borane liquid, which would allow us to use the same pump infrastructure.”
Dixon said drivers would pull up, pump out the ammonium borane waste and pump in recycled ammonium borane.
“Using that existing pump infrastructure with service stations would keep the capital cost down in terms of the total investment,” Dixon said. “And this way we’re actually able to regenerate and recycle what fuels our cars.”
As it stands, the technology is still not ready to bring to market. Dixon said the hydrogen equivalent of a gallon of gasoline costs roughly $8.
“But really, if you think about it, that price is pretty competitive in Europe,” Dixon said. “Ten years from now it’s going to be a totally different economy for hydrogen, though, and you could see that price get cut in half by then or sooner.”
For that to happen, Dixon said he and his colleagues will need to find a cheaper way to produce hydrogen.
“If you’re making hydrogen with natural gas, that can be expensive and if you’re doing it with oil you’re not solving the problem of our dependency on foreign oil,” Dixon said. “We’re currently working to find a way to provide a very cheap source of hydrogen by splitting it from water molecules using solar energy.
“I think as we build a foundation of good work that will show the viability of the processes, that will hopefully change the minds in Washington.”
