According to Conservation Magazine’s reporting of an Environmental Science & Technology publication, “It can take 800 gallons of irrigation water to produce the amount of corn necessary to make one gallon of ethanol.”
Here is a breakdown of the amount of water needed to produce the fuels needed to quench our energy needs (Liters per Megawatt hour):
Oil refining: 80-150
Oil Shale: 170-681
Natural Gas Combined Cycle power plants: 230-30,300
Coal: ~900
Nuclear, closed loop cooling: ~950
Geothermal, closed loop cooling: 1,900-4,200
Enhanced Oil Recovery: ~7,600
Natural Gas Combined Cycle power plants, open loop cooling: 28,400-75,700
Nuclear, open loop cooling: 94,600-227,100
Corn ethanol irrigation: 2,270,000-8,670,000
Soybean biodiesel irrigation: 13,900,000-27,900,000
Data: Conservation Magazine July/Sept 2009
