Suspicious of Suspicions

Last week's Economist has a piece bashing ethanol as biofuel.

No problem with that; it seems very unlikely that biofuels can produce enough fuel to make a detectable impact on fossil fuel consumption without causing huge impact on food production. The arguments are familiar.

But this piece concentrates on another issue: "A typical ethanol factory producing 50m gallons of biofuels a year needs about 500 gallons of water a minute... All this is putting a heavy burden on aquifers in some corn-growing areas."

Yeah, another reason, see? Government programmes, blah, picking winners, blah, public choice theory, blah blah blah, I'm right as usual.

Wait a sec. Gallons per minute? How many minutes are there in a year? Hmm, about half a million. So the processing for a gallon of ethanol uses 5 gallons of water.

Is the Economist really trying to tell me that using 5 gallons of water to produce a gallon of ethanol is a big deal? I mean, you get 3 molecules of water back when you burn a molecule of ethanol, anyway. How much water does it take to grow the damned stuff in the first place?

Being right isn't enough, one needs also to be selective in the arguments one employs. Stuff like this actually makes me suspicious as to why biofuel is being attached. Is it just for the good reasons, with this bad reason being picked up by accident, or is there something else to it? Come to think of it, didn't I read somewhere that the "Indonesian deforestation due to palm oil biofuel cultivation" story was rubbish too? Maybe that's another bad argument.

The Economist's source is the Institute for Agriculture and Trade Policy, "a non-profit, tax-exempt organization, with the mission of fostering sustainable rural communities and regions". They sound a little dodgy, but I'd expect their bias if anything to be pro-Ethanol rather than anti. They seem to have a small-farmer slant; maybe they're worried about biofuel production bidding up resources (like water) used by their constituency.

Now this is odd. Their recent publication on the issue is Biofuels and Global Water Challenges. But that is, as the title suggests, concerned with global biofuel production, notably in the developing world. The "Achilles heel" quote in the Economist is quoted in this, but originates in a 2006 report by the same organisation, Water Use by Ethanol Plants: Potential Challenges. The "Global Challenges" report estimates the crop water requirement for producing a gallon of ethanol in Iowa to be about 1100 gallons - which would make the demands of processing about half a percent of the total. "Compared to feedstock production, water use in corn-based ethanol plants itself is negligible".

The Economist article also refers to a court case over the building of an Ethanol plant in Missouri. In that case also, it is the use of water in growing the corn that is causing the most concern:
"Frankly, not so much worried about this plant using 1.5 million gallons of water a day, even though we live in a semi-arid area," said Lowell Brakey, spokesman for a group of Wright residents who filed a lawsuit over the new plant and lost. "We're worried about the corn."
So what is this article up to? Is it just sloppy reporting? Is it plugging a product? (it refers to "Delta-T Corp, a Virginia company which has designed a system that does not discharge any waste water"). More here.

Beats me. I think there's another source to this article which I haven't found. If someone could isolate where the "gallons per minute" figure is coming from, that might be the key: it seems to have been expressed in that way to make it seem like a lot of water without putting it in context.