As Gas Prices Rise, UF Researcher Crafts Alternative Power Plant

April 3, 2000

GAINESVILLE, Fla. — With prices at the gas pump hovering around $1.60 a gallon, a University of Florida researcher is improving on a new technology that could make cars three or four times more efficient without sacrificing comfort or power.

Eric Wachsman, an associate professor of materials science and engineering, recently received a $450,000 grant from the U.S. Department of Energy to build on promising research results involving fuel cells. The three-year project could hasten commercial application of a type of fuel cell known as the solid oxide fuel cell that would replace the internal combustion engine as the automobile’s power plant.

“There’s no question that the fuel cell is going to play a role in the automobiles of the future,” he said. “The question is which type of fuel cell will be used.”

Automakers and university researchers are pursuing the development of two main types of fuel cells: proton exchange membrane fuel cells and solid oxide cells, Wachsman said. Both rely on an electrochemical reaction to produce electricity, which then is used to provide power for the vehicle motor. Solid oxide cells have the potential to convert available fuels, such as gasoline, directly into electricity. Proton exchange membrane cells, by contrast, require another step: an on-board fuel processing unit to convert the gasoline or other fuel into hydrogen, which then is converted into electricity.

Wachsman said the conversion process is complex and decreases the efficiency of the power system. It also adds significant cost, in part because it seeks only to produce hydrogen, rejecting other ingredients in the gasoline or other fuel, such as carbon. The alternative to the conversion process, however — powering cars with tanks of highly explosive hydrogen — is potentially dangerous and impractical.

“If you go to a hydrogen-based system, you’ve got to store hydrogen and that would require a whole new transportation infrastructure,” he said. “The cost to convert every gas station in the U.S. to dispense a gaseous hydrogen instead of a liquid fuel would be a major impediment.”

Besides not requiring hydrogen, solid oxide fuel cells are nonpolluting and highly efficient. But they also have a major downside: They require an operating temperature of over 1,800 degrees Fahrenheit, far higher than the 220 degrees required by the proton exchange membrane fuel cell. For this reason, most research involving solid oxide fuel cells to date has focused on development of the cells for stationary power generation. “If you wanted to start the car with the current generation of solid oxide fuel cells, you would have to wait an hour or so for it to start up,” Wachsman said.

Wachsman and colleagues in fuel cell research have demonstrated and patented an electrolyte, a major component of the solid oxide fuel cell, that can operate below 1,000 degrees. The goal of his current research is to reduce that temperature to about 500 degrees while improving the electrolyte’s performance and reliability. “If we can achieve this goal the start-up time will be comparable with the proton exchange membrane fuel cell,” he said.

Wachsman said he can’t say when the solid oxide fuel cell might appear in cars, in part because consumer application of the technology depends on the decisions of policy-makers, the automobile industry and the price of gasoline. Whatever the date, the likely application for the fuel cell will be a fuel cell-battery combination known as a hybrid, he said. The fuel cell will constantly charge the battery, which will run the electric motor powering the car.

“Fuel cells give you a lot of energy density, or the ability to travel long distances, while batteries give you power density, or the ability to accelerate quickly,” he said. “A hybrid allows you to have both at the same time.”

Wachsman added the start-up time would be less of an issue with a hybrid car, because the car would start immediately on battery power while the fuel cell warms up.

Wachsman is not alone in pursuing the solid oxide cell for automobiles. BMW, Toyota and Nissan all have solid oxide fuel cell programs. “If gas prices in the U.S. were the same as in Europe and Japan, we would see fuel cell powered automobiles here very soon,” he said.