Ethanol Facts List

For those that argue the reason for ethanol is "energy independence" let's look at the extreme of replacing automotive gasoline with E-85

Summary
Replace USA 141 billion gallons of gasoline with E-85 fuel =>170 billion gallons of E-85
146 billion gallons ethanol
26 billion gallons gasoline
Require equivalent of 117 billion gallons of gasoline for production and distribution
440 billion gallons of water for processing
235 quadrillion gallons of water for processing
250 billion pounds of fertilizer
$182 billion in ethanol plant capital

Items
Gasoline usage July 2007 USA gasoline - 388.6 million gallons/day
=141 billion gallons of gasoline/yr

In a study on automobiles on E-85 and gasoline it was found that fuel efficiency was reduced 27 percent with ethanol (Sheehan, et al. 2004).
1.2 gallons of E-85 = 1 gallon regular unleaded gasoline
=170 billion gallons of E85

How much ethanol would be required for 170 billion gallons of E85
146 billion gallons ethanol/yr, growing at about 5 billion gallons/year
and 26 billion gallons of gasoline

Acres of Corn
Corn to ethanol yield about 280 gallon/acre
Corn average 113 bu/acre
2.5 gallon per bu
=280 gallon per acre=520 million acres of corn
This last year corn acreage = 80 million acres

Water usage
452,000 gallons per acre
=235 quadrillion gallons of water
Production requires about 3 gallons water/gallon ethanol
=440 billion gallons water processing

Fertilizer usage - 477 lb/acre => 250 billion lbs
Nitrogen 124 lbs/acre
Potash 53 lbs/acre
Phosphate 58 lbs/acre
Lime 242 lbs/acre

Production efficiency
The best case production of ethanol yields about 25% more energy than is used in growing the corn, harvesting it, and distilling it into ethanol. Others estimate that it takes more energy to create corn ethanol than it provides

Where would we get the energy for fertilizer, to produce the corn and refine/distribute the ethanol? The answer given is coal and natural gas.
To simplify the net energy balance, lets compare in gallons of gasoline. Assuming the best case above 25% energy yield, this would mean 117 billion gallons of gasoline to produce the corn. Add the 26 billion gallons in the E-85, the total is 145 billion gallons

Plant capital costs
Average about $1.25 per gallon/yr capacity
146 billion gallons/yr => $182 billion in capital facilities

Ethanol Distribution
Ethanol and e-85 are more corrosive than gasoline and soaks up water and impurities, they cannot be shipped through the existing gasoline pipeline network, trains, trucks or barges. This is also why vehicles need to be specially built to run on E-85.