Khosla is a super-salesman. You have to take him as such. However, Jeff Broin says he can make cellulosic from corn cobs for $2.50, Now, and he says he's pretty sure he can do it for $2.00/gal when his Emmetsburg, Ia, "project Liberty" starts producing in 2011. I gotta take him pretty seriously. He's "earned" the respect.

Mascoma's made some waves in the last couple of days with their announcement that they've developed an enzyme that will combine, IIRC, 3 processes into one.

Plus, Khosla's "Range Fuel's" Soperton, Ga. plant will be kicking off in 2011; so we might not want to Completely disregard Everything he says.

The trick in cellulose, I think, will be their ability to get "efficiency" in smaller plants. Transport looks to be a stumbling block if they can't.

I agree with RR that cellulosic ethanol is a pipe dream. Poet which is a large ethanol producer with a plant 14 miles from my house, plans to use corn cobs. Their Emmetsburg pilot plant is an add on facility to their regular ethanol plant if I am not mistaken. It is I believe funded by a government grant.

I have a hard time with their estimate of costs to arrive at the $2.50/2.00 for cellulosic ethanol. As was the case with corn, as the use of corn cobs ramps up, so will the price. Even now I do not understand how they price cobs as a feed stock. There is no futures market. Feed stock is the most important cost in making ethanol.

When/if ramped up cobs use happens the price of cobs will skyrocket. It has to as cobs are not something that is suited to current infrastucture like corn. They require unique equipment to gather and store in large quantities. They are also very bulky. Our local elevator estimates that to keep a typical local 100 million gallon ethanol plant running on corn cobs would require a semi load arriving every 8 minutes around the clock.

This, if it were happen, means that the price of cobs must be high for farmers to buy the combine gathering attachments, semi's, storage facilities and equipment to handle them. If the price of cobs should stay low or "free" (since they are now waste) farmers will not invest and there will not be enough supply. I believe this to be more or less true for other cellulosic ethanol schemes.

Those other sources of cellulose which look so tempting are probably in fact expensive even if the technical problems are solved. Trees may look like a gift the first time they are used, but then it takes years to replenish the supply. Money, land and labor costs have to be taken into account.

The final nail in the cellulosic ethanol coffin is the questionable wisdom of growing a single use crop in the first place. Suppose down the road push comes to shove and animal/human food demands price corn such that ethanol is truly uncompetitive as most on this site hope. What then? If corn is the feed stock, the solution is to shut down some plants as is happening now due to low liquid fuel prices.

If those corn acres or other acres are diverted to single use cellulosic ethanol feed stocks this can not happen. We are stuck. I read yesterday where a proposed plant in Mississippi was to convert pasture to biomass cane for ethanol. Clearly this is sacrificing food for biomass feed stock. Those cattle that were grazing on the supposedly unproductive pasture were in fact part of the nation's food supply even more than corn.

Dual use crops such as corn for ethanol make more sense than cellulosic ethanol.