Water and Whine
Posted: March 18, 2008
If you are going to talk about water use, at least put it in perspective.
The hue and cry over ethanol’s water use has been led by the claim that one gallon of ethanol requires 1700 gallons of water to produce. That figure, as Ken pointed out in the previous post, counts the water used to grow the corn, most of which comes in the form of rainfall. That recurring figure of 1700 gallons, which originated in the infamous Pimentel study, continues to be bandied about by naysayers who don’t even bother to compare it to anything else. How about the fact (according to these EPA Water Trivia Facts) that one acre of growing corn actually gives off an estimated 4,000 gallons of water PER DAY in evaporation? That means that corn actually gives back more water than it uses to grow!
According to the same trivia facts, it takes 44 gallons of water to refine one gallon of crude oil (actually 1851 gallons to refine one barrel, which is 42 gallons). That could be legitimately compared to the 3-4 gallons of water it takes to process corn into a gallon of ethanol. According to the St. Petersburg Times, a typical 40-million-gallon-a-year ethanol plant uses almost exactly the same amount of water per as an average 18-hole municipal golf course. Why aren’t we seeing any editorials claiming that golf courses are going to drain the aquifers?
Here are a few other bits of trivia regarding “how much water it takes to….”
Process a quarter pound of hamburger - one gallon
Brush your teeth - two gallons
Make one board foot of lumber - 5.4 gallons
Process one can of fruit or vegetables - 9.3 gallons
Make one gallon of paint - 13 gallons
Make one pound of wool or cotton - 101 gallons
Make one barrel of beer - 1500 gallons
Make four new tires - 2,072 gallons
Manufacture one new car, including tires - 39,090 gallons