- The Washington Times - Friday, March 9, 2001

In a 34-year career with General Motors, Robert C. Stempel directed numerous innovative engineering projects, including creation of the Oldsmobile Toronado the first modern-era front-drive American car the all-plastic Pontiac Fiero sports car and GM's first catalytic converter.
Mr. Stempel, who retired as chairman of GM in 1992, is now a principal player in helping to steer the automotive industry into the hydrogen age. Hydrogen is seen by many experts as the most desirable fuel for vehicles because it produces only trace amounts of emissions that make many urban areas foul places to live. But using hydrogen is fraught with major problems.
Energy Conversion Devices Inc. (ECD) , a company Mr. Stempel now heads, has created a unique hydrogen storage system for fuel cells that solves many of these complex problems. The fuel cell was invented in the 19th century, but had little practical use until it was employed on the Apollo space missions. Fuel cells now offer the most promising technology for pollution-free auto propulsion. In fact, most of the world's leading carmakers promise to have fuel-cell cars for sale by 2004.
Fuel cells create electrical energy by combining hydrogen and oxygen. The reaction of the two elements creates power for an electric motor and the only emission is water vapor. That's the ideal case when pure hydrogen is used to combine with oxygen. But storing pure hydrogen is a difficult engineering feat and most carmakers use fuel cells that get energy from liquid hydrocarbon fuels such as methanol or gasoline.
Separating hydrogen from these sources, however, is complicated and difficult. It requires a reformer, a device that uses steam to free hydrogen atoms from the fuel. In addition, the carbon atoms in the fuel combine with oxygen to form carbon dioxide, an undesirable greenhouse gas. The amount of CO2 is far less than that normally created when you burn fuel in an internal combustion engine, but not really desirable.
ECD has invented a solid hydrogen storage system that's well suited for fuel cells. The system stores hydrogen atoms in a metal and the product is called metal hydride. It looks like a powder but can also be made as a solid. It is perfectly safe to store aboard a vehicle compared to liquid or gaseous hydrogen.
In addition, ECD's proprietary technology enables more hydrogen to be stored per liter of hydride than either gaseous or liquid hydrogen. ECD's metal hydride provides 103 grams of hydrogen per liter. Liquid hydrogen contains only 71 grams per liter and compressed hydrogen (at 5,000 psi) provides only 31 grams. What's more, once an infrastructure for distributing the hydride is created, the car can be refueled in about the same time it takes to fill a gasoline or diesel fuel tank.
Mr. Stempel's company is also using metal-hydride technology to create a new generation of batteries that produce triple the voltage of today's conventional 12-volt batteries. ECD announced its solid-state storage system two years ago. It is now building a plant in Ohio with a capacity to produce at least 30,000 36-volt batteries annually by 2003. Carmakers are planning on introducing 36- and 42-volt electrical systems within a couple of years to meet the increasing demand needed to run electrical systems in vehicles.
The metal-hydride batteries are substantially smaller than batteries made with conventional chemistry systems today. That means the batteries will occupy less space in cars and trucks. These batteries will also be substantially lighter in weight.
The technologies Mr. Stempel is helping to steer toward the marketplace may seem less exciting than producing powerful vehicles like the Oldsmobile Toronado or stylish sports cars like the Pontiac Fiero, but unless the auto industry can produce cleaner-burning vehicles, the emphasis will always be more on fuel economy than performance. Electric vehicles with limited performance and range certainly haven't excited drivers up to now. Clean-burning hydrogen can help fuel a new breed of exciting cars and trucks in this century.



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