What’s more, fuel cells produce energy without combustion – heat and water vapor are the only byproducts – so the technology holds great promise for reducing greenhouse gases responsible for global warming.

“Propulsion experts agree that cars in the near future will be electrically-driven and fuel-cell powered to satisfy the need for environmentally responsible transportation,” said Robert C. Stempel, former chairman and CEO of General Motors and current chairman of Energy Conversion Devices, Inc.

“A consensus is also forming, in both the automotive industry and energy supply sources,” Stempel wrote, in an article for the North American Precise Service, “that hydrogen will be the ultimate fuel of the 21st century.”

In its natural form, hydrogen is bulky and can be hazardous. Liquefying it uses a lot of energy and requires exotic storage tanks. According to technicians at Sarkeys Energy Center at the University of Oklahoma, the most significant obstacles still to be overcome in efforts to put fuel cells to practical use are storing and delivering hydrogen gas to the cell. Until recently, the most promising means for real-world use seemed to be extracting hydrogen from methanol – a complex and expensive process.

However, Stempel’s company has developed a metal-hydride storage system that, he says, “offers a cost-effective, safe, and efficient means of transporting the energy necessary for vehicles of the future.

“A metal hydride system,” Stempel explained, “consists of hydrogen gas, engineered metallic material, and the space where they interface.” The powdered metal absorbs the hydrogen gas. When the mixture is heated, the hydrogen gas comes out and can then be fed directly to a fuel cell which provides the electric energy to power the car.”

According to Stempel, recent advances in metal-hydrides make storing sufficient hydrogen to power a fuel cell-driven electric vehicle several hundred miles much easier. “Unlike alternative methods under consideration for future cars, carrying hydrogen as a solid in a metal-hydride is by far the safest approach,” Stempel said.

“In addition, ECD has recently found a way to more than double the amount of hydrogen that can be carried this way, making the whole system much smaller than earlier ones. The company’s researchers have also resolved the problem of getting the hydrogen out of the hydride again, so a typical fill-up would require only three or four minutes.”

Stempel added that recent tests suggest that metal-hydride systems will provide more than 2,000 refills, or hundreds of thousand of miles, with no fall-off in performance.