[Greenbuilding] bio fuels and ethenol

[YankeePerm at aol.com]

Soybeans, corn (maize) and sugar cane are the big three soil destroyers.   
Better to exhaust the petroleum supply than destroy the soil. Petroleum has much 
less intrinsic value. It matters not whether the soybeans are grown 
organically.   They just destroy soil at a slightly slower rate.   Of course it is 
POSSIBLE to grow soybeans in a way that does not destroy soil, but nobody does.   
This also requires much less fossil energy to produce the beans.   However, 
this topic is already far afield for this list and I'll not push it further with 
agronomic discussions.

I am extremely skeptical that soybeans produce more diesel fuel energy than 
it takes to grow them, not even including energy embedded in farm equipment and 
infrastructure.   One of my students in our online class reported that 
ethanol from corn now has been tweaked up to a 20 percent margin above direct energy 
used in cultivation and processing...nothing to get excited about but better 
than I expected.   Since maize is several times as productive as soy, or any 
nitrogen fixer, I doubt if you are not consuming more petrol by using soy than 
if you just bought gasoline.   Plus you are diverting food for your private 
transportation. My guess is that it would take something like double the energy 
in a gallon of soy diesel to produce it, but that may be too generous.   Of 
course you get a feed supplement from the mash, but on an energy basis that will 
not compensate for the conversion.

Dan Hemenway



---------------------------------------------------------
Barking Frogs Permaculture Center
www.barkingfrogspermaculture.org

Our 12th Annual Permaculture Design Course Online begins Oct. 14, 2007. The 
protocol for our Annual Permaculture Design Course Online is at 
http://www.barkingfrogspermaculture.org/Protocol7_05_06.pdf
Our next live program is Aug. 17-26th on Nantucket, Massachusetts. Contact 
Dylan at dryfly2000 at yahoo.com for details.

A list by topic of all Yankee Permaculture titles also may be found at

http://www.barkingfrogspermaculture.org/YPCpublicationsbycategory.pdf

 





**************************************
 See what's free at http://www.aol.com.