No fast solution

I wrote about "The coming 500 mpg car" earlier this month to explore whether the technology presently exists to improve fuels efficiencies enough to obviate the need for significant amounts of imported petroleum.

The 500 mpg car is more accurately the "500 miles per gallon of gasoline" car, since as envisioned it would use a lot more than one gallon of fuel to go 500 miles. But only one gallon would be gasoline. The rest would be E85 ethanol or electricity, the key feature being a long-range battery that can be recharged by a wall outlet as well as by the gasoline motor in the car.

The main fuel problem, though, is producing the ethanol to make E85, a combination of 15 percent gasoline and 85 percent ethanol. Despite the genuflection of the Congress and the Bush administration to agri-business and the legendary family farmer, making ethanol from corn (maize) is non-cost-effective. A enormous amount of energy is used to plant, fertilize and harvest the corn plants and transport the crop to a conversion plant, where nothing is used but the kernels. There simply is not enough energy in corn kernels to make it work. In fact, it has never been demonstrated with high assurance that corn ethanol consistently yields more energy than it takes to make it. Then there is the moral issue of reducing food production to make corn ethanol. Corn is not just a table staple, it is a crucial feedstock staple; growing corn for ethanol rather corn feeds will make food the next global crisis.

An excellent primer on ethanol economics, and biofuels in general, is, "Biofuels: Doing the Math."

There are, fortunately, other ways to make ethanol than using corn, and these other methods not only promise positive energy ratios, they promise lopsided ratios. Switchgrass, which once covered the Great Plains, has been under testing by the Dept. of Energy for a few years. Researchers now believe that its energy output can be up to 540 percent of the energy inputs needed to produce it.

But that's not the best news. What if we could use ordinary garbage to make ethanol? General Motors is betting it will work. GM has partnered with Coskata Inc. of Chicago to run test activities to determine whether it's possible to convert "renewable carbon-rich materials ranging from cornstalks and woodchips to old tires and city trash into clean-burning ethanol at a cost of roughly $1/gallon." That, I assume, means a production cost of $1 per gallon, not the retail price. Even so, it is much cheaper than any other ethanol so far.

Even though GM intends 50 percent of its new auto production to be flexfuel capable within five years, "GM research suggests that by 2030, one-third of transportation fuel needs can be met by biofuels." Make that "only" one-third. So the idea that we can quickly wean ourselves off oil-driven transportation is not realistic.

But the idea of turning eyesores like this into auto fuel is very appealing, yes?

The United States throws away 250 million tires every year,more than one per driver. Recycling them into ethanol is a really good idea.