General Motors introduced this week three additional models designed to burn high concentrations of ethanol, part of a major trend in the auto industry to offer flexible fuel vehicles.
Although ethanol has a low public profile as an alternative fuel in California, it is rapidly gaining attention in the Midwest, where the corn-based fuel is primarily produced and more widely available.
A blend of 85% ethanol (a form of alcohol) and 15% gasoline is sold as E85 fuel at 727 U.S. gas stations, mainly in the Midwest. The fuel contains about 25% less energy than traditional gasoline, so fuel mileage drops and the cruising range on a tank decreases.
But proponents say that it will eventually provide a cost-effective alternative to gasoline and will reduce U.S. dependence on foreign producers of crude, as well as creating an indigenous U.S. industry that supports farmers.
The E85 buzz in California is muted, reflecting that most E85 is made in the Midwest and that California air regulators are concerned the fuel has still unknown impacts on air quality. So far, only one retailer in the state sells E85, a gas station in San Diego, according to the National Ethanol Vehicle Coalition.
Some military and government facilities, however, are burning the fuel and California has a demonstration project for E85 in the Bay Area.
GM, perhaps reflective of its Midwestern roots, offers 17 vehicles with E85 compliant fuel systems and engines, one of the auto industry's largest lineups.
"It is a big deal in the Midwest, because of the farming industry here," said Andy Buczynsky, a GM fuels engineer. "It is considered very American."
Ethanol has had an uphill battle proving its validity. For many years, the product was pushed by politically powerful agriculture interests in the Midwest and supported by government subsidies. But in the past, more energy in the form of coal and oil was used to make ethanol than the ethanol contained.
The case for ethanol is getting better. New technology is helping to increase the efficiency of producing the ethanol.
Alexander Farrell, a UC Berkeley professor of energy and resources, said that on average, U.S.-made ethanol contains 25% more energy than is used to make it. Coal and natural gas are used to help distill corn into ethanol, meaning that E85 puts the sun's energy, coal and natural gas into vehicle fuel tanks.
The newest plants are putting 67% more energy into the product than used in the manufacturing, said Michelle Kautz, a spokeswoman the ethanol coalition, based in Missouri.
Brazil leads the world in ethanol use. It has the advantage of using sugar cane rather than corn, producing an ethanol that contains several times as much energy as is used to produce it. Eventually, U.S. scientists hope to make a breakthrough that would enable many kinds of organic farm waste and even trees to be converted to ethanol.
Ethanol does not yet make a lot of economic sense for U.S. consumers. To be economical, it should sell at 20% to 25% less than gasoline. In many locations, the E85 fuel costs the same as gasoline or even more. Kautz said she is aware of one station in Missouri that discounts E85 by 50 cents a gallon so that it should be at parity with gasoline for vehicle operation costs.
The high cost of E85 reflects the strong demand for ethanol. A lot of gasoline already being used in California and elsewhere contains up to 10% ethanol as an octane booster (to reduce engine knocking). The phasing out of MTBE, an octane booster that raised human health concerns, has increased the demand and price of ethanol. On average, about 5% of the total volume of gasoline sold in California is ethanol, said Farrell, the UC Berkeley professor
Supporters of E85 say eventually the production of ethanol will meet demand and it will be at least as cheap as gasoline. And E85 may have other benefits.
"Producing flexible fuel vehicles is part of GM's effort to reduce America's dependency on foreign oil," said GM spokesman Tom Read. "For every 37 gallons of E85 used, one barrel of oil is saved. Because E85 ethanol is a renewable fuel made from U.S. grown bio material it helps reduce greenhouse gas emissions."
But if you want to use E85, even if you can find it, you need a special E85 compliant vehicle. An E85 car or truck is a flexible fuel vehicle, meaning it can burn regular gasoline or 85% ethanol. Engine sensors determine what percentage of the fuel is ethanol and adjust fuel injectors to squirt more or less fuel into the engine, Buczynsky said. Because ethanol has less energy content, the injectors must put in more fuel per cylinder.
You should not try to burn E85 in a vehicle designed only for gasoline, because it can cause engine damage. Compared with gasoline, ethanol has less of what engineers call lubricity, the ability to help lubricate moving parts. So, E85 vehicles use tougher metal and plastic parts. E85 compliant vehicles either have a yellow fuel cap or a label on the fuel filler door.
Ralph Vartabedian can be reached at ralph.vartabedian@