Blueprint for Viable Biofuels

Biofuels can be produced in large quantities and with a relatively small carbon footprint, but only if they are made from certain sources, according to a report in the journal Science. Authored by scientists from the University of Minnesota, Princeton University, and three other universities, the paper said that biofuels will only be sustainable if they are largely produced from non-food crops. The authors identified five types of biofuels that can be produced in volume and with minimal greenhouse gas emissions: perennial plants grown on degraded lands or abandoned agricultural lands, crop residues, sustainably harvested wood and forest residues, mixed cropping systems, and municipal and industrial waste. The paper said that these sources could yield 500 million tons of biomass per year, which would meet a significant amount of the U.S. demand for transportation fuels.