I’ve discussed research on biofuels in earlier posts, including one from last summer. Now Prof. David Tilman at the University of Minnesota and others have published another study that demonsrates the advantages of prairie grass over corn as a crop for producing ethanol. Here are some quotes from a December 7 StarTribune story, “Grass beats corn in ethanol study“:

University researchers, led by Tilman, think they’ve found a solution — supply the facilities that make ethanol with a diverse mixture of prairie grasses instead of corn. The grasses not only can produce more net energy per acre than corn but they also act as a sponge for greenhouse gases before being harvested, soaking them out of the air and into their roots and surrounding soil, the researchers found.

The last trait could prove an economic bonus for farmers if businesses one day are able to cash in “credits” for removing greenhouse gases from the air, as many predict. Clean air credits already are traded in Europe….

In a cover story published today in Science magazine, the researchers reported that a field planted with a medley of prairie grasses and flowering plants packed more than triple the energy of single-variety grasses. The study also estimated that mixed prairie grasses grown on marginal farmland would yield 51 percent more energy per acre than corn cultivated on fertile land.

The prairie grasses were grown on depleted land without fertilizers and pesticides commonly used for corn. The grasses require almost no maintenance, so less gasoline and diesel fuel would be burned tending to fields….