Sunday, May 21, 2006
Forked-tongue arguments for ethanol
Not long after the seminar, I wished I had a recording of my question and the exchange and Dale's response. Then, when I found these comments, I immediately said "That's him!" (Which, of course, may actually not be the case at all.)
I'm posting the comments here rather than just a link because I don't want them to disappear, as I intend to come back to them at some length. These comments are exquisitely deceptive and misleading, and they merit detailed analysis. I especially like the subtle suggestion that people who question ethanol might not like capitalism.
I think you're wrong about ethanol and that EROEI analysis is a waste of time. Somewhere in your education you learned that energy was conserved when it was converted from one form to another. Many people seem to think that this means that the economic value of energy is conserved as it is converted from one from to another. They act as if 1 million BTU of energy was equally valuable regardless of the form it is in. Wrong! 1MMBTU in the form of coal costs about $1.50. In the form of natural gas it costs $6.55 today. In the form of wholesale gasoline you will pay about $16 today. Ethanol at $2/gal works out to be $26 / MMBtu. The high price is likely due to ethanol's value as an oxygenate and octane enhancer. Using 2 MMBtus worth of coal to make 1 MMBtus worth of ethanol makes sense when you understand that clean transportation fuels are much more valuable than power generation fuels. Although an economic analysis is the best way to evaluate ethanol, if you don't like capitalism then you could just look at MMBTU's of transportation fuel consumed versus MMBTU's of transporta[t]ion fuel produced. That ratio is around 1:8 if I remember rightly. Consult the recent article in Science about biofuels if you want the exact number.
There's another reason I dislike EROEI analysis which is that I have always suspected that it would be very difficult to do such an analysis accurately and fairly. It depends too much on details of farming and industrial practise which are subject to change and for which accurate data is hard to find. It seems that the biggest energy input is the distillation step. As ethanol distillation is a fairly low temperature process, it is a good candidate for the use of waste heat from some other industrial process like power generation. If that became standard practice, then it would make a big difference to the EROEI calculation.
Speaking of power generation, the EROEI for operation of a modern coal burning power plant is about 0.36! Most of the input energy ends up in the cooling water. Maybe we should stop making electricity! I'm sure candle making has a better EROEI than that!