Wanna know why the wars in Iraq and Afghanistan are so expensive? Here's one big reason: The U.S. military consumes 22 gallons of fuel per soldier, per day. And each gallon costs $45 or more to haul to the battlefield.

That's according to a new Deloitte study, flagged by our friend Paul McLeary at Aviation Week.

Actually, $45 per gallon is a lowball estimate; according to the Navy, it's more like $300 to $400. (Talk about sticker shock.) But the costs of guzzling that much gas won't be measured just in dollars, the study warns. Fuel has to be driven in to Afghanistan's isolated bases. Which opens up U.S. convoy to improvised bomb attacks. Which invariably leads to troops dying. "Absent game-changing shifts, the current Afghan conflict may result in a 124% (17.5% annually) increase in U.S. casualties through 2014," according to Deliotte.

The Defense Department has all kinds of isolated initiatives to try to cut down its dependence on fossil fuels: massive solar arrays, hybrid rides, trash-powered generators. But most of these efforts are concentrated on making the Pentagon's domestic operations more energy efficient. For the troops in the field, it's still a steady diet of gas.

[Photo: U.S. Army]

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