Researchers debate what we know about green fuelsby Stephanie Hemphill, Minnesota Public Radio
St. Paul, Minn. — The debate over biofuels continues. About 40 people met at the University of Minnesota Tuesday to discuss the state of knowledge about how much ethanol and biodiesel can reduce greenhouse gas emissions.
Speakers included one of the coauthors of a controversial paper released last February on the so-called carbon debt from converting wild land to produce corn ethanol and a visiting researcher from the Argonne National Laboratory.
They said scientists don't know enough about many aspects of ethanol production to fully analyze its impacts.
Researchers use models to predict land use changes, but the models are designed for other purposes, so they're not accurate for predicting life-cycle greenhouse gas emissions.
They agreed the most promising raw material to fuel cars and trucks and cut down carbon emissions at the same time is cellulosic material, waste from forestry, agriculture and perennial grasses.