Re: Energy Cost of Ethanol
- From: "cnctut" <cnctutwiler@xxxxxxxxxxxxx>
- Date: 28 Jun 2006 20:46:02 -0700
Timo A. Nieminen wrote:
On Thu, 28 Jun 2006, glhansen@xxxxxxx wrote:
cnctut wrote:
Certainly there are many side issues with corn to ethanol. Greg
Hansen's original post was aimed at a statement seen on the web
frequently--"1.5 gals petrol needed to make one gal ethanol." We could
have used any variety of crops to address that statement from beets to
cellulose--but since corn issues are in the news, I chose that product.
The article said that figures range from 1.4:1 to 1:1.5, so whether
corn fuel even breaks even still seems to be in dispute. Too bad it
didn't have citations. There are other, more distant approaches, like
breaking down cellulose. But one at a time.
The economics are interesting, too. Like the price of ethanol going
from (what was it..?) $2.45 per gallon to $4.60 per gallon when it
started being added to fuel. Something similar would surely happen to
the price of sugar of whatever origin if it became the common feedstock
for fuels. But that's not "Would it reduce our reliance on fossil
fuels?", it's "Is it worth it?"
Given that ethanol can be bought for $0.35/litre or so, and people are
making money from it, $0.35 worth of fuel input is an absolute upper
limit. (Btw, my earlier sugar-based upper limit should have been about
$0.70/litre - I used the higher $500/ton white sugar price rather than the
lower $350/ton raw sugar price. Yeast is not that fussy.)
There are two separate components of the fuel input: that required to grow
the corn/sugar/beets etc, and that required to convert it to ethanol. The
first can be estimated from the prices for corn, sugar etc - generally the
farmer is making some money from it, so the cost of fuel used can't exceed
the selling price. Apparently ethanol prices are driven mostly by supply
and demand of ethanol, and are quite resistant to changes in corn prices
(where made from corn); this suggests that the cost of corn isn't that
large a part of the overall final price.
--
Timo Nieminen - Home page: http://www.physics.uq.edu.au/people/nieminen/
E-prints: http://eprint.uq.edu.au/view/person/Nieminen,_Timo_A..html
Shrine to Spirits: http://www.users.bigpond.com/timo_nieminen/spirits.html
Timo--good points--and if anyone has purchased a small bag of corn meal
anytime over the last 10 years, you should be wondering why that bag
was so expensive knowing the farmer was paid 15 cents for the only
ingredient.;-)) Those darn ag subsidies--hehe!
.
- References:
- Energy Cost of Ethanol
- From: Greg Hansen
- Re: Energy Cost of Ethanol
- From: cnctut
- Re: Energy Cost of Ethanol
- From: Greg Hansen
- Re: Energy Cost of Ethanol
- From: cnctut
- Re: Energy Cost of Ethanol
- From: cnctut
- Re: Energy Cost of Ethanol
- From: cnctut
- Re: Energy Cost of Ethanol
- From: cnctut
- Re: Energy Cost of Ethanol
- From: cnctut
- Re: Energy Cost of Ethanol
- From: glhansen@xxxxxxx
- Re: Energy Cost of Ethanol
- From: Timo A. Nieminen
- Energy Cost of Ethanol
- Prev by Date: Re: Nonrenormalization vs Renormalization 79.1: Superposition, Phases, Linearity As A Causal "Boundary Value Problem"
- Next by Date: Re: WTC explosion-plume TRAJECTORY -- 911
- Previous by thread: Re: Energy Cost of Ethanol
- Next by thread: Re: Energy Cost of Ethanol
- Index(es):
Relevant Pages
|