Yesterday I came across a head-turning new biofuels study by researchers at the University of Minnesota that found that planting a mixture of native grassland perennials produces biofuels more efficiently than corn and soybeans (no surprise) and even more efficiently than any single-grass plots (hmm, interesting).

According to team leader David Tilman, the most diverse plots produced 238 percent more bioenergy yield than the average plot containing a single species.

As I was going back to post on this, however, I saw that biofuels made the cover of Science this week, due to back-to-back publication of the above study and one on carbon-negative biofuels. The latter describes efforts by researchers at MIT, the Whitehead Institute, and the Berlin Institute of Technology to engineer yeast with increased tolerance and production of ethanol. The outcome, the authors project, will be that ethanol could go from being highly resource intensive (and net carbon positive) to “carbon-negative.”

I have a lingering question, which I didn’t see addressed in the abstracts: does this research apply equally to corn-based ethanol and cellulosic ethanol? Because while this could be a great boon to cellulosic production, I am afraid that any improvement in the corn ethanol process will just fan the flames of its supporters. Because ethanol is ethanol no matter from whence it derives, I have a feeling it could be applied to both processes … which of course puts the onus on us to devote these engineered tools to the best of the biofuels. As the first study points out, the “best” is clearly not corn or soybeans, but grasses — most likely a patchwork quilt of them.

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