How far can you drive on a bushel of corn?
Crunching the numbers on alternative fuels.
On the outskirts of Garnett, Kan. (pop. 3362), the horizon is broken by what at first sight seems to be a grain elevator rising above the cornfields. But closer inspection reveals a tall, skinny distillation column among the silos and fermenters, identifying the complex as part of the nation's energy future: It is East Kansas Agri-Energy's ethanol facility, one of 100 or so such heartland garrisons in America's slowly gathering battle to reduce its dependence on fossil fuels. The plant processes about 13 million bushels of corn to produce approximately 36 million gal. of ethanol a year. "That's enough high-quality motor fuel to replace 55,000 barrels of imported petroleum," the plant's manager, Derek Peine, says.
Given that 1 barrel (42 gal) of crude yields 19.5 gal of gasoline,
36m gal of ethanol = 55k barrels of crude = 1.07m gal of gasoline
Given that 13m bushels = 36m gal of ethanol
1 bushel = 2.8 gal of ethanol = 0.08 gal of gasoline
So gasoline is 34x more potent than ethanol?? And each bushel of corn (70 lbs) only produces an equivalent of 0.08 gallons of gasoline? (Conversely, it takes 875 lbs of corn, or 12.5 bushels, to produce the equivalent of 1 gallon of gasoline).
For such a wonder fuel, it seems remarkably inefficient.
Ace also brings up a good question when he wonders what the relative costs (financial and energy) of production between the two are.
Blatantly stolen from Ace of Spades