'Autos on steroids' keep US gas thirst super-sized

Rising levels of obesity and the McMansion trend of the real-estate bubble era already provide evidence enough that the US has a “Super Size Me” problem. But the love of bigness has also derailed efforts to curb the nation’s thirst for imported oil.

Between 1980 and 2006, cars sold in the US could have seen their fuel economy rise by a whopping 60 percent, thanks to technology and design improvements by automakers. However, in real life, the average real mileage on the roads improved by a little more than 15 percent. The rest of the fuel-saving benefits, new research from the Massachusetts Institute of Technology (MIT) has found, was lost to ever-growing auto weights (26 percent) and increased horsepower (107 percent).

MIT economist Christopher Knittel dubs the effect, “Automobiles on Steroids.”

Knittel doesn’t blame the auto companies. If anyone’s responsible for failure of improved auto efficiency to translate into real-world energy savings, it’s Adam Smith’s infamous “invisible hand” of the marketplace.

“I find little fault with the auto manufacturers, because there has been no incentive to put technologies into overall fuel economy,” Knittel said. “Firms are going to give consumers what they want, and if gas prices are low, consumers are going to want big, fast cars.”

While the price for crude oil — as well as gas at the pump — hit new highs in 2008, the cost of fuel had before that been trending downward. Adjusted for inflation, gas prices dropped by 30 percent between 1980 and 2004.

If more efficient vehicle designs alone aren’t the cure for the US’ oil addiction and global climate change, what is? Knittel sees the solution in a higher tax on gas consumption. Only then will motorists begin to value fuel as the valuable resource it is, and start making efforts to use a whole lot less of it.

“When it comes to climate change, leaving the market alone isn’t going to lead to the efficient outcome,” he said. “The right starting point is a gas tax.”