My favorite part of the State of the Union speech was when President Bush said the word “switchgrass.” I’ve mowed acres of the stuff, so there was a burst of familiarity like you would feel if you saw a former college roommate on “Jeopardy!” But perhaps even more important, it was encouraging to hear the big guy, who never saw a piece of land that didn’t deserve a test hole, say that we need to find better sources of energy.

Hmmm. Produce our own energy instead of pouring billions of dollars and thousands of lives into some of the most dysfunctional areas on the planet? Might be worth a try.

Now that ethanol has climbed to new heights of respectability, it’s comforting to believe that the future is bright here in a state that’s hip-deep in raw materials. Switchgrass aside, corn is the stuff we talk about when we talk about ethanol. And it’s reassuring to assume that all of the common-sense groundwork was done before ethanol production plants started sprouting up everywhere.

If you want to hang on to that warm, cozy feeling, whatever you do, don’t talk to David Pimentel.

Produce energy from corn? In the retired Cornell University professor’s view, that’s about as sensible as melting down six nickels to make a quarter.

According to his research, you have to expend 29 percent more fossil-fuel energy to make ethanol than you get out of the finished product.

Most interested observers who would really, really like to see more corn turned into ethanol – the U.S. Department of Agriculture, the Iowa Corn Growers Association, the Iowa Renewable Fuels Association, etc. – say Pimentel must be holding his calculator upside down. They point to a study that says you get 67 percent more energy out than you put in.

Negative 29 percent vs. positive 67 percent. This is the kind of mathematical discrepancy that emptied out the Enron office tower in Houston.

We called Pimentel and asked him if his critics have changed his thinking during a debate that has gone on for 20 years or so. “No, they really haven’t,” he said.

He says the Government Accountability Office and 26 top scientists all confirmed his figures long ago. Yes, it was long ago, say ethanol proponents; he hasn’t taken into account the greater efficiency of higher crop yields.

But the biggest leap in Pimentel’s logic might be the inclusion of everything that goes into manufacturing the farm machinery. Maybe some of those tractors and combines wouldn’t exist if we raised less corn, but they’re not built and bought just to raise corn for ethanol. Figures don’t lie, but sometimes they get kind of confused.

“(Critics) claim we’re using obsolete data and counting too many things,” Pimentel said. “But I’d say they’re not counting everything.”

Here’s another point Pimentel would like you to consider: U.S. ethanol makers produced 3 billion gallons last year, he said, which represents 14 percent of the corn crop and 1 percent of the fuel we used in our vehicles. If you used the entire crop – which you couldn’t; cows have to eat, too – it would fulfill a mere 7 percent of our driving-around needs.

But ethanol does help farmers, right?

Well, a little, said Pimentel, who grew up on a farm and wants to see farmers prosper. “ADM [Archer-Daniels-Midland] and Cargill are getting $7 per bushel of corn in subsidies,” he said. “Looking at it optimistically, farmers are getting 2 cents a bushel. It’s a real brainwash saying farmers are benefiting from this; it’s ADM that’s benefiting. It’s a real boondoggle.”

But then, science isn’t the issue here; it’s politics. So let’s plunge ahead and hope that ethanol is, at the least, not a bad thing for the U.S. economy. The corn is really starting to pile up around here.