[CarlinsDarlin]

Federal agencies must prefer bio, not petroleum, products
http://www.newfarm.org/news/0105/011305 ... -pro.shtml

I read this today, and at first was delighted. Then I thought about it, and I'm not quite sure what difference it will make, since commercial farmers are putting in row crops/monocultures. Someone who knows a lot more about this than I do - please comment? Bytesmiths?

Besides the fact that these are renewable - and therefore potentially lessen the demand for oil in agriculture (which is in itself a big plus), what other benefits are there to using the biobased products? I mean, it seems to me, it would be healthier for the soil, for example. Perhaps I am wrong...

Regardless, I am really ignorant in this area, and would like to learn more. Thanks,
Kathy

[BabyPeanut]

The question is what is the EROEI.

http://www.eroei.com/

If you are using waste vegetable oil then the EROEI is good because you get quite nearly something for nothing.

If you grow corn deliberately just to make ethanol you are probably expending more energy than the ethanol is worth. Not to mention what corn does to the soil.

There are a lot of shades of gray in between.

[smallpoxgirl]

Recent lengthy (and rather acrimonious) discussion of the pros and cons of biodiesel here. http://www.peakoil.com/fortopic4379.html

My calculation of the EROI for canola biodiesel is about 3 to 1. By my reconing, the negative impacts of stripping off the existing plant cover from the land and planting it in monoculture, petrochemical canola vastly outweigh the benefits of a 3 to 1 EROI.

IMHO, it's mostly just green-washing.

[CarlinsDarlin]

thanks baby peanut and smallpoxgirl. That was kind of my take too - after I thought about it. Good PR for the masses, but no big difference in the long run. Oh well.
K

[smallpoxgirl]

$this->bbcode_second_pass_quote('BabyPeanut', 'I')f you grow corn deliberately just to make ethanol you are probably expending more energy than the ethanol is worth. Not to mention what corn does to the soil.