General Motors Corp. demonstrated a gasoline-fed fuel cell vehicle, a prototype that could lead the way for future uses in cars, homes, and businesses. The Chevrolet S-10 fuel cell pickup uses a fuel processor, which reforms low-sulfur gasoline to produce electricity for the vehicle. The gasoline is mixed with air and water. The mixture then passes over catalysts that separate the hydrogen from the carbon. The fuel cell stack receives the hydrogen, producing electricity after combining with oxygen from the air. Using a reformer fuel cell, the pickup approaches 40 mpg, and boasts up to 40 percent overall energy efficiency. Except for trace amounts of carbon monoxide and hydrocarbons, regulated emissions are almost eliminated. The process could eliminate carbon dioxide emissions if the system was available at gas stations. In the next year, GM will continue to test the vehicle in numerous areas, including efficiency, emissions, and fuel-reforming qualities.