Some see biofuel as a way to lessen our dependence on foreign oil and slow global warming, but a new study by economists at Oregon State seems to say: "Not so fast."

OSU publicized the study Monday. It says that when all the costs and subsidies are considered, biofuel is very expensive to produce and doesn't reduce greenhouse gas emissions nearly as much as slightly increasing vehicle mileage standards. The study was the work of economists in OSU's College of Agricultural Sciences including William Jaeger, Robin Cross and Thorsten Egelkraut.

Among the conclusions in the study's summary:

• "Per unit of energy, corn ethanol is estimated to cost 750 percent more than gasoline; canola biodiesel is estimated to cost 125 percent more than petroleum diesel; and the cost of cellulosic wood-based ethanol (which the researchers said is not yet commercially feasible) is nearly 200 percent higher than gasoline."

• Various methods of controlling emissions of the greenhouse gas carbon dioxide cost around $50 per ton. The cost estimate is $10,700 per ton by using corn-ethanol; $580 a ton for biodiesel, and $350 a ton for wood-based ethanol. "Hence, other policies aimed at reducing greenhouse gas emissions appear to be significantly more cost-effective than a shift to these three biofuels."

• If Oregon had plants making 50 million gallons each of corn and wood ethanol and 2 million gallons of canola biodiesel, the net energy they produce would amount to slightly more than 1 percent of annual consumption of oil energy. "Together they would reduce U.S. greenhouse gas emissions by one-eighth of 1 percent."

But, the report said, such plants would require lots of resources and have lots of bypoducts.

"To satisfy 1 percent of Oregon's current petroleum energy consumption with canola biodiesel would require over 400,000 acres, or 100 times the current canola acreage in Oregon.

"This amount of canola would generate 600 million pounds of canola meal, enough to feed five times the number of cows currently raised in Oregon."

The authors conclude: "For comparison, the degree of energy independence resulting from a one-mile-an-hour increase in average motor vehicle fuel economy in Oregon would be equivalent to three to four corn ethanol plants … or 13 biodiesel plants like the one evaluated here."

The full report, titled "Biofuel Potential in Oregon: Background and Evaluation Options," is available on the Web at arec.oregonstate.edu.