Congress has established a goal of replacing 30% of U.S. petroleum consumption with biofuels by 2030. A DOE/USDA report (feedstockreview.ornl.gov/pdf/billion_ton_vision.pdf) identifies 1.3 billion tons of annual dry biomass production potential from US forests and cropland. By mid-21st century, this would be converted into cellulosic ethanol by biorefineries.