Pop quiz on driving costs

Without resorting to cheating-via-Google, and without putting a lot of thought into it, what do you think it would do to the per-mile cost of owning and driving a car in the US if we added a 100% tax to gasoline. That’s right, not a piddling little 10 cents here or 50 cents there, but a big, hairy-chested, visible-from-space, smack-you-in-the-face-with-a-2×4 100% tax on top of the current cost and existing taxes.

Would you believe that for the average American driver and the average car it would increase the per-mile cost by only 20%?[1]

Before anyone leaps to the (wrong) conclusion that I’m advocating an instant 100% tax on gasoline, let me explain my point: People have a very skewed idea of what it costs per mile to own a car. The total is much higher than most people realize, simply because so many large contributors to that figure are paid very seldom, but in much large increments. Insurance, maintenance, license and registration fees, loan interest, and depreciation don’t come to mind nearly as quickly as does the price you paid at the gas pump two days ago.

This is far more than a charming little observation about market psychology; this perception issue has very significant public policy ramifications in the US (and likely many other countries, I’d guess). The painful truth is that a sizable portion of our CO2 emissions come from the transportation sector (one third, in fact, just over two billion metric tons/year), and trying to give people enough incentive to drive less and drive more efficient vehicles, at least to the extent needed to make a big dent in that 2 gigtons of CO2 will almost surely entail higher gasoline prices. But how do we get a public policy in place if every politician who decides to support such a measure is sure to be carpet bombed with ads from his or her opponent in the next election that scream about the ravages of paying an extra 50 cents (or however much) per gallon?

Yes, in the grand scheme of things it’s not the most important point, I suppose. But it’s yet another example of the kind of myopia and misunderstanding that will slow or block us from taking the needed steps to minimize the impacts of climate change.

[1] This calculation is based on the latest edition of AAA’s “Your Driving Costs” [PDF]. That booklet shows that for 15,000 miles/year, the average car has a per mile cost of 56.6 cents, with gasoline being 11.36 cents/mile.