There are two iron laws of energy policy in the United States. Iron Law No. 1: A higher federal excise tax on fuel would efficiently reduce gasoline consumption and its negative side effects (air pollution, traffic congestion, carbon emissions, dependence on foreign oil).
Iron Law No. 2: Although economically rational, gas taxes are politically unpopular, so Congress will go to almost any length to avoid raising them, even if that means resorting to far less transparent policies.
Hence we have Corporate Average Fuel Economy (CAFE) standards for cars, which take a Ph.D. in mathematics to comprehend — and increase the price of a new automobile by hundreds of dollars.
Hence, too, we have elaborate government mandates and subsidies for blending ethanol into gasoline, which cause farmers to divert land, water and capital into growing corn and other crops for fuel rather than food.
True, ethanol policy became somewhat less irrational at the end of 2011, when Congress finally allowed a $6 billion annual tax credit to expire.
But a 2007 federal law mandating ever-greater ethanol consumption remains on the books, and it is starting to create the economic equivalent of a multi-car freeway pileup.
Known as the Renewable Fuel Standard (RFS), the law requires refiners to blend 36 billion gallons of ethanol and the like into transportation fuels by 2022.
Alas, like many previous attempts at central planning, the RFS has run afoul of changing realities in the marketplace — specifically, a seemingly permanent leveling-off of motor-fuel consumption due to changing driving habits, the sluggish U.S. economy and CAFE standards, among other factors.
As it happens, gasoline consumption hit an all-time high of nearly 9.1 million barrels a day in the year that Congress passed — and President George W. Bush signed — the RFS. It has since dropped by half a million barrels a day, and the Energy Department forecasts that the downward trend will continue through 2040.
The result is that the fuel industry is about to hit a "blend wall." The 2007 standard calls for producers to blend more ethanol into gasoline than the market can absorb at the current standard rate of 10 percent per gallon.
Producers can still meet their regulatory obligations by buying obscure, tradable credits known as Renewable Identification Numbers, or RINs.