A company in Geneva, Illinois, is building big, powerful engines used in agriculture, long-haul trucking, construction and more, but with a twist: Instead of being powered by diesel, the ClearFlame Engine Technologies engines are powered by 100% ethanol, which is made mostly from Midwest corn. ClearFlame was founded by Stanford grads BJ Johnson and Julie Blumreiter. Johnson says he expects a big rig putting on 100,000 miles a year will be able to save about $25,000 in fuel costs using ethanol. They’ll be ready to do long-haul road testing this summer, and an unnamed major manufacturer of farm tractors and machinery is already on board and ClearFlame is integrating its technology in new equipment coming off the production line.