I think that those studies are full of ____.
Hydrogen has a negative EROEI. You can never recover as much energy from hydrogen as is expended in separating it from water. It is a terrible carrier of energy, packing about the lowest, when considering containment systems and the hydrogen itself, energy per pound. Yet it is praised by these two studies.
Most studies have given Ethanol a EROEI (energy Returned For Energy Invested) of at least 1.8:1 for corn as a feed stock. When other feedstocks are considered, corn stover, switchgrass, paper mill effluent (Xethanol), Rice Straw (Pacific Ethanol), Straw (Iogen), Forest waste products (Pacific Ethanol), Municipal Garbage and sewage. EROEI of as high as 8:1 has been quoted.
The article did not state what method is used for conversion of cellulosic material old methods used either acid and high heat, or high heat gasification and were very inefficient.
I am not sure what method Pacific Ethanol is planning to use, but Iogen is using enzyme reduction of cellulose at about 10 cents per gallon of ethanol produced. Xethanol is using a proprietary yeast found in wood borer beetle guts that converts cellulose to ethanol directly. (no extra cost).
Xethanol is building in conjunction with paper mills, using their effluent waste as a negative feed cost feed stock. The water from the paper process has short fiber cellulose in large quatities, the short fiber is not suitable for paper. It has been land filled up till now. Kind of like Veridium's DAF Oil Extraction Process, Veridium is paid both for the oil extracted and the reduction in waste that had to disposed of through land application.
Corn ethanol produces up to several hundred gallons of ethanol per acre. Utilization of the Stover can increase that to well over a thousand gallons per acre, competitive with sugar cane. I don't think that several hundred gallons of gasoline or diesel are used in the production of corn per acre. If it were farmers would be quite broke at $1500 for fuel per acre, and only $2.15 per bushel for 200 bushels.
Arguments of negative EROEI for biofuels just don't make real world sense. Maybe in academia .
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