Fuel cells for transportation

Within five years, luxury cars and recreational vehicles on the showroom floor may be equipped with solid oxide fuel cells. That's the prediction of Subhash Singhal, director of Pacific Northwest National Laboratory's fuel cell program. Fuel cells will use the vehicle's existing fuel supply to provide auxiliary power for creature comforts, such as air-conditioning, keeping drinks cold in mini-refrigerators and viewing DVDs--all without running the vehicle's engine or draining its battery.

Fuel cells also could power refrigeration units in semi-trucks during rest stops, instead of idling engines which is responsible for about 90 percent of a semi's emissions.

PNNL is developing solid oxide fuel cells (SOFC) for military applications, such as powering individual soldier's equipment, as well as for commercial power plants, distributed generation for residential and commercial use and auxiliary power units for public and personal transportation. SOFCs also may be clustered for large-scale stationary power generation.

Similar to batteries, SOFCs convert chemical energy into electrical energy. However, fuel cells never require charging and don't run down as long as a fuel supply is available. SOFCs are fuel flexible, meaning they can use a variety of fuels, including natural gas, gasoline, diesel or hydrogen.

"Not only can SOFCs use traditional fuels, with the absence of a combustion process the fuel is used more efficiently with little to no emissions," Singhal explained. Once fuel cells are in place, combustion engines would be used solely for driving the vehicle. PNNL and Delphi Corp. have successfully demonstrated an auxiliary system for a BMW sedan that required no major modifications to the vehicle.

A team approach

PNNL helps lead the Solid-State Energy Conversion Alliance (SECA), an alliance of U.S. industry, universities and other research organizations. Its goal is to create an SOFC technology by 2010 that will offer a low-cost, high-efficiency system for less than $400 per kilowatt for stationary, transportation and military applications.

The National Energy Technology Laboratory coordinates SECA's Industrial Teams, which develop SOFC systems for specific markets and products. PNNL coordinates SECA's other key area, the Core Technology Program, which provides technical solutions to overcome barriers identified by the industrial development teams.

"Relying on the 40 to 60 percent increase in fuel efficiencies of individual electric systems powered by fuel cells, the U.S. can extend the use of fossil fuels, reducing dependence on imported oil," said Prabhakar Singh, who manages and directs the Core Technology Program for PNNL.