Here's the webpage on a National Academy of Sciences study on the comparative
benefits of ethanol (from corn) vs. biodiesel (from soy beans), i.e., using
ethanol as a fuel, not just as an oxygenator. Biodiesel beats ethanol hands
down. See http://www.pnas.org/cgi/content/abstract/0604600103v1 The
conversion of farm lands that would otherwise produce food to feed a starving
world is a downside, and if all were converted, it would end up only
satisfying a small portion (12%) of our energy needs. The study looks at the
total energy budget from the use of ammonia-based fertilizer (which takes
loads of natural gas to manufacture) to production and distribution.
In Brazil, they extract the sugar from sugar cane for ethanol and then use the
byproducts to fuel power plants. Ethanol from sugar is many times more
efficient than corn. So efficient that we have a high tariff on imported sugar
from Brazil. Since this note is non-political, I won't say why. The Brazilians
now have ethanol and conventional fuel at stations and since ethanol is only
70% as efficient as gasoline, they let the market decide. I don't know how
they mitigate the effects of ethanol on conventional fuel systems, unless they
use specially designed cars (E-85). See Tom Friedman in the Sept. 15th & 20th
edition of the NYTimes.
The breakthrough that is anticipated is using the remaining cellulose
(portions of the stalks left in the field) to greatly increase ethanol
production. This technique would apply to corn, too, but more importantly,
would allow the use of marginal lands not used for food production.
The other downside of ethanol as an oxygenator is it does little to reduce
smog. Again, the National Academy of Sciences
http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=9461
The bottom line is that 10% ethanol is probably okay for our non E-85 LBCs,
but still adds to smog, and there is, as yet, no great economic advantage in
using ethanol as an alternative fuel.
Maybe we should convert our LBCs to biodiesel (:-)
Jerry
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