More than meets the eye – Carbon efficiency isn’t the whole story for biofuels

In Wisconsin, a study from researchers at the University of Wisconsin–Madison and the Great Lakes Bioenergy Research Center compared two processes for producing biofuels from corn stover: biological conversion to ethanol (BCE) and catalytic conversion to alkenes (CCA) and found that carbon efficiency isn’t the only factor for determining promising strategies for the production of biofuels.

Their results show that three parameters – carbon efficiency, process energy requirements (the energy required to produce the fuels in a biorefinery), and fuel efficiency in a vehicle’s engine – are important, and that the most carbon efficient strategy may not automatically be the most effective strategy overall.

They found that the CCA strategy, despite being less carbon efficient, achieves better results overall because it produces more mechanical energy from both electricity and fuel. The paper suggests that research on optimizing strategies to produce alternative biofuels and bioproducts remains important, even if it does not achieve the high carbon efficiency of strategies like BCE that produce ethanol.