OT ---Energy requirements of Ethanol Production
As a long-time chemical engineer manque and applied agro-energy economist (farmer), I can tell you that it is very difficult to do an an accurate energy balance calculation for ethanol. As you know, sugar or starch must be grown, using persticides, fertilizers, mechanical cultivation, weeding, using energy intensive machinery and fuel , the crop harvested, juices pressed, fractionally crystallized, and wastes (fibre) disposed of, molasses distilled into rum or vodka, products and by-products packaged, shipped, as sugar, rum, and fibre f.i. The point in this process where biomass (other than molasses) should be fermented, fractionally distilled, and standardized into fuel is the outcome of complex maximizing analysis. The cheapness of petroleum now, prevents production of cheap ethanol even from cheap corn or sugar, certainly not from American corn and sugar. Subsidization of ethanol to conserve petroleum is absurd. To reduce pollution is a weak objective -- because ethanol is in terms of pollutants per mile much worse than many of approaches (electric car), especially if gasohol rather than alochol is used a fuel.
Few generally truthful statemens can be made except that it present detailed technical problems for economists, agronomists, mechanical, electrical, chemical engineers, that are very sensitive to small changes in systems parameters. Lay people without specialized know are wasting their time in research these problems, becausr the can hardly understand the problems until they have studied the basics for which they lack the time or opportunity. Modelling alternative energy systems requires guesses about gigantic systems even small examples of which have not been built. Off and on for 54 years I have speculated about the cost of (hot) fusion plants. I don't think anyone knows anything worth knowing about the economics of fusion energy now, so that nothing resembling rational planning for future energy can be done. My own guess is that we will go through at least five different energy regimes before the first fusion plants gat a chance. They will not be economical. I help study the energy-economics of a gigantic seaweed farm GE Systems was planning. No one knew what the cable would ne (we liked kevlar but who knew how long it would hold together in saltwater. The whole thing collapsed when the Iran excitement blew over. I know that hundreds of independent engergy groups are working on totally wild, totally weired technologies and products. The are "surprises" and no one can predict with any confidence what effect they will have on the energy future. We believe that ethanol, fusion, coal, liquefaction, gasification, biomass, kelp, corn, shale, tidal, OTEC, frozen gas, etc. etc. are all reserve technologies, but the R&D to bring them to market and the capital investment to recover and refine the fuels will not be available until $10/bbl oil is gone. IMO, there is a real possibility that pig and chicken excrement are more likely to be successes than many others because these are a waste product, easily gasified, and must be disposed of sofely at all costs.
As for foreseeing $10 oil, I and many others did. I tried to persuade DOE-NSF to allow me to use $10 (1985 c.d. price), but they laughed me to scorn in a large energy-employment model we were doing for them. Many economists (Adelman and many non-industry petroleum and mineral economists) during the 70's and 80's argued that the oil price crisis was temporary and would dissipate steadily, but with interuptions.
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