What is meant when referring to the “generation” of biofuels?
First generation biofuels are primarily created from feedstocks that have also been used as food sources, e.g. ethanol from corn and biodiesel from soybean vegetable oil or animal fats. Second generation biofuels are made from nonfood feedstocks. e.g. cellulosic ethanol made from the cellulose or cell wall of plant cells. Feedstocks for this next generation of biofuels include forest residues (sawdust), industry residues (pulp and paper waste), agriculture residue (corn stover), municipal waste and biomass (wheat straw and switchgrass). Third generation biofuels will be nonfood-based feedstocks and indistinguishable from their petroleum counterparts, e.g. algae.
