It is interesting to note that, although the energy return on investment (EROI) for corn-derived ethanol is way out of the ballpark of reasonableness (required benchmark of 5:1 versus an estimated 2:1 for corn ethanol), Bruce Dale still recommends pursuit of a vast increase in the use of ethanol to, as he says, leverage our liquid petroleum resources (C&EN, Feb. 14, page 11 and C&EN Online, cenm.ag/cov1). Whereas this may indeed prolong our dwindling, easily recovered petroleum supplies, it seems to me to be a very expensive and not very sustainable approach.
What about the tremendous water requirement to run these ethanol operations? What about the need for the very large amount of fertilizers to support all this new agriculture?I think that if the EROI is properly calculated to include all the direct and ancillary inputs and outputs, it should be a fine metric, but I question the appropriateness or the utility of the use of the liquid/liquid ratio. It seems more of a contrivance to make biofuels look more favorable than they really are.
Although I do not have sufficient hard data at this time, my general impression of the whole biofuel industry is that it is heavily subsidized and, if left to stand on its own, would quickly wither and die and that no amount of economy of scale would change that outcome.
Kenneth J. Caldwell