The U.S. Senate passed the much-debated Energy Bill this morning, which Iowa’s senators say could mean a huge economic boost for the Hawkeye State. Republican Senator Chuck Grassley says one amendment would more than double the production of renewable fuels like corn-based ethanol and soy-based biodiesel to eight-billion gallons a year by 2012. We only produce three-and-a-half billion gallons now so there’ll be a phase-in period. Grassley says the mandate is there to encourage investment in ethanol in case there’s a slow-down in use. Iowa is the nation’s leading ethanol producer. Grassley says several elements are included in the massive bill that would help Iowa farmers and others. Grassley says they include tax credits for wind, biodiesel, ethanol, biomass and conservation tax credits for fuel cell cars. He expects the conference committee meetings with the House on the Energy Bill will be taking place over the next month while the legislation should be before President Bush by August first. Democrat Iowa Senator Tom Harkin says the doubling of ethanol production within seven years is key. Harkin says “The eight-billion gallon renewable fuel standard is an important milestone but it’s not our final destination.” He says in the coming years, the nation must be more aggressive in promoting the “bio-economy.” Harkin says fellow Democrat Senator Charles Schumer of New York was mistaken when he said the ethanol plan would ultimately raise gas prices.Passage of the Energy Bill would set the stage for what could be a spirited conference with the House, which passed its version of the measure earlier this spring. The House version does -not- include the mandate for eight-billion gallons of ethanol, nor any of the renewable energy production tax credits on wind and biodiesel.