Ethanol’s been in the news a lot lately, given a real boost by Bush’s mentioning it in his state of the union speech. Ethanol has a sketchy history. Production in the 70s and 80s was apparently a net energy loser (that is, more fossil fuel energy was required to create a gallon of ethanol than that gallon could displace), and while its reputation as an energy loser remains, more recent evidence seems pretty convincing that ethanol is now a net energy winner. There’s a rundown of the debate at the Institute for Local Self-Reliance’s “New Rules
” website. A recent analysis of ethanol energetics [175 kb PDF file]
was published in Science
. The authors come to a very interesting conclusion, that while producing ethanol is a distinct energy saver compared to producing gasoline, the net greenhouse gas release into the atmosphere is not much better for ethanol under current technology. Their model predicts that the adoption of “cellulostic” ethanol technology will lead to meaningful reductions in GHG releases, relative to gasoline. (Virtually all ethanol today is derived from corn because of corn’s high sugar content. Cellulostic ethanol is derived from plant materials, like the now fast-becoming-famous switchgrass, that don’t have much or any sugar content.)
One thing that I noted previously is that using plant cellulose for ethanol production means that plant material is not being allowed to return to the soil. This can result in reduced soil quality. It can also be a problem from the point of view of GHGs, because adding organic matter to soil is a terrific way to sequester carbon, removing it from the atmosphere. (Yet another reason to support farms that rely on compost and manure for their fertilizers instead of industrial NPKs.) I’m sure there’s some ideal balance between using some portion of a crop for ethanol and leaving the remainder on the farm, but it’s something that will have to be figured out.
The ILSR brings up another issue regarding ethanol: the changing status of its economics. Until now, ethanol has been only a moderately sized business, and many ethanol factories are relatively local facilities owned as farmer co-ops. That meant that the value-added in converting corn to ethanol went back, at least in part, to the farmers. However, with an ethanol boom in the offing, new facilities are planned that are mega huge, requiring outside investing. The result is likely to be that Wall Streeters will get the profits from the value-added, while the farmers will be back to square one as mere suppliers of a commodity input. ILSR’s David Morris writes on how to “ensure a biofuels industry that truly benefits rural America
.” [large file: 1.4 meg PDF]