Ohio Gov. Bob Taft is expected to sign into law a bill mandating state vehicles run on a cleaner-burning mix of gasoline and ethanol, but rising prices and lack of suppliers are obstacles, according to the Associated Press.Ohio owns 11,500 vehicles, not including law enforcement vehicles or state cars for elected officials. The state’s 6,700 biodiesel and ethanol-ready vehicles, mostly owned by the Department of Transportation, would be required to buy alternative fuels when “reasonably available and reasonably priced.” Of that number, 2,100 of the state cars and light trucks can run on a gasoline mix with 85 percent ethanol, called E85. While biodiesel is more readily available, lack of production and rising demand are limiting the ethanol supply. Supplies are expected to increase, with a plant to open next year in Lima and developers hoping to build four more. In addition, incentives in the bill would help retailers cover the cost of installing E85 pumps at gas stations.The bill would require the state to use 1 million gallons of biodiesel and 60,000 of E85 in 2006 as a means of setting an example for the retail market. The fleet is close to meeting the biodiesel usage goal, but is 43,200 gallons away from meeting the E85 goal.