Flex Fuel U.S.
Mitch Sremac

Watching a program on Brazil's ethanol-fueled cars one evening in his Streeterville home, Mitch Sremac wondered: What would it take for people in the U.S. to start running their cars on alcohol, too? For today's fleet, his answer was a fuel-conversion kit. After 18 months of tinkering and $1 million from friends and family, Sremac, 55, an auto-parts company president, built just such a device'the first to be certified by the U.S. Environmental Protection Agency'and established Flex Fuel U.S., with himself as chief executive, in October. The Flex-Box Smart Kit is about the size of an old Walkman and mounts under the hood of a car. It automatically sips the fuel to determine its alcohol level and throttles the fuel injector accordingly. The kit allows cars to drive smoothly on everything from E85, a blend of 85% ethanol and 15% gasoline, to pure gasoline. Flex Fuel is field-testing its product in a Chicago police car and hopes to begin retailing the kit at $1,295 in April.

—Chi-an Chang (posted on June 6, 2008)