Engineer Poet -

That was a very good rejoinder to Mr. Khosla's lengthy ethanol apologia. You hit upon many of the same things that bothered me about his arguments, most of which are very pursuasively put forth but based on some highly dubious premises.

The thing that immediately told me he was on the wrong track was his blatent comment that EROEI is irrelevant. This was shortly followed by two highly erroneous statements about the EROEI of making gasoline in a refinery and the EROEI of electricity.  Mr. Khosla appears to be highly technically savvy, so I doubt these statements were made out of ignorance.

He also makes much of the fact that the he is not only invested in ethanol but also in a variety of other good things. Of course we don't know what his investment portfolio actually looks like, so we don't know to what extent ethanol dwarfs these other investments. If one were to go by how hard he's been pushing ethanol, one could probably safely conclude that ethanol is what he is really all about these days.

I was also a bit lost when he started talking about
'trajectories' and ethanol having the best trajectory. Trajectory toward what? I hate buzz words!

Then, like you, I felt that if ethanol is so great, why does he think we'll gradually transition away from it toward some of the alternatives mentioned?

The bottom line is that Mr. Khosla is selling something (i.e., the idea that ethanol is a great thing that will help us solve our energy problem). And like all good salesmen, he is arguing as strenuously and pursuasively as he can that you should buy what he's selling. I for one am not.

You mention corn as America's most productive crop.

I think it's important to note that the level of productivity we have achieved is sutained by a massive use of fossil fuel and ff products for fertilization, pest control and planting/harvesting.

I have seen figures suggesting that this energy input at the front end is tripling the productivity of the modern American acre.  If we lose the cheap oil, what is the next best source of fertilizer and how intensively can we farm using it?

If we are trying to replace gasoline, then the corn/biomass production is going to be gas-free or limited.

I am willing to bet that all current production estimates are including all of the productivity advantages that cheap oil has bestowed on us.

Funny you should ask.  I wrote an essay on nitrate production from corn stover last November.  I concluded that the Rentech plant under construction could take corn stover (or charcoal derived from it) and produce more than enough nitrogen to fertilize the corn, plus several times the diesel required to cultivate it.

The "balance of system" probably wouldn't be doing quite so well, though.