TotalSonic wrote on Wed, 23 June 2010 13:07 |
Problem is the EROEI (energy returned on energy invested) is actually a very poor ratio on ethanol - especially in comparison to more traditional fossil fuels.
|
Steve,
The EROEI for sugar cane Ethanol here is between 8 to 10:1, depending on several conditions. According to
www.theoildrum.com , the current EROEI for oil is at about 6 (2007 estimate; I have no idea how they arrived at this figure).
From actual experience in Brazilian sugar cane Ethanol plants, after you start the process the plant not only produces the Ethanol but also injects back into the grid excess electricity from its generators that run on the sugar cane residues; the corrosive byproduct is reprocessed, again using energy generated by the plant itself, into fertilizer.
When you burn the Ethanol in your car, the CO2 emissions can be no greater than the CO2 that was removed from the atmosphere by the sugar cane as it grew; basically Ethanol is liquid solar energy.
As for the concerns that there won't be enough area to grow all the sugar cane needed, well... oil will end sooner or later and we can't 'grow' it... some people will have to get used to the idea that they should not drive in their daily commute that 2-ton truck that can tow the boat they don't own up the hill that they don't live near.
Sugar cane Ethanol as produced today in Brazil has been called "a first-generation alternative fuel with the overall performance of a third-generation one" by foreign experts.