Biofuels: A Home-Grown Response to the Energy Crisis
by David Tenenbaum
In the early 1900s, inventor Rudolph Diesel built an engine that ran on vegetable oil. But crude oil was cheap, and diesel engines are fueled entirely from petroleum.
The pendulum is swinging back. Rising petroleum prices and tightening supplies have sparked a flurry of interest in "biofuels"--fuel derived from biological sources. The most promising are biodiesel, extracted from plant oils and burned in diesel engines, and ethanol, fermented from corn and other biological materials, and burned in gasoline engines.
Ethanol is surging in Brazil, where it powers 40% of the vehicle fleet. However, Brazil has a much smaller auto fleet, and has a climate suited to growing sugar cane, an ideal source of ethanol. While only about 2% of American gasoline contains plant-derived alcohol, within five years, 5% of road fuel is expected to contain biofuel in the U.S., India, and Europe.
Because biofuels are domestically produced--literally home grown--they could reduce or stabilize oil imports. They reduce pollution. And they could ease the global warming crisis. The carbon dioxide they release is taken up by growing plants in a closed loop that could reduce the earth-heating impact of transportation. Eventually, cheaper and more abundant biofuels may help solve some of the worst drawbacks of our highly motorized lifestyle, without reducing mobility.
What do you need to know about biofuels? Let's look first at ethanol--an industrial version of the kick in beer, wine, and whiskey.
Not yet hooked on alcohol
Gasoline companies have been blending a small amount (usually 10%) of ethanol into some gasoline for years, largely to reduce air pollution. Ethanol is made for fuel just as it is for whiskey: by fermenting organic material and distilling the alcohol to concentrate it.
Ethanol usually is made from corn grain, and while any increase in demand gratifies farmers, ethanol has not revolutionized the economics of farming or driving. Now, with global oil supplies maxed out and the slightest interruption of supplies--whether from a hurricane or unrest in the Mideast--causing price hikes, ethanol looks to some like the fuel of the future.
Ethanol contains about 30% less energy per gallon than gasoline.
While 10% ethanol can be burned in most cars, 85% ethanol (called "E85") requires "flexible-fuel" vehicles built to handle the fuel. After years of quietly making flex-fuel cars (to get a break on federal mileage requirements, not to push biofuels), car makers suddenly are swilling at the ethanol tap. GM, for example, plans to sell more than 400,000 E85-capable vehicles in 2006. (Is yours a flex-fuel car? See the sidebar.)
The car companies are catching the ethanol train. Ford has signed an agreement with ethanol-maker VeraSun Energy to establish an "ethanol corridor" E85 pumps through Illinois and Missouri. GM, which expects worldwide ethanol production to triple by 2020, is collaborating with VeraSun to open ethanol stations in the Twin Cities. The oil industry also is high on ethanol (get it?). In January, BP's chief scientist wrote that it is time to "get serious" about biofuels.
To decide if flex-fuel is worth factoring into a future purchase decision, consider these ethanol pros and cons:
Pro:
Reduced air pollution. Ethanol cuts emissions of carbon monoxide and carbon dioxide. The fuel evaporates slowly, reducing the escape of volatile compounds from the tank and while refueling.
Reduced dependence on foreign oil. Biomass (plant materials used for fuel) for ethanol is domestically produced, and some waste material can be fermented to make ethanol.
Possible cost saving. Some states offer tax credits for purchasing a flex-fuel vehicle (see sidebar).
Biofuel is renewable (grown above ground, not pumped from declining underground sources).
Biodiesel is getting attention from country-music legend Willie Nelson, who is pushing "Biowillie" at some truck stops.
Con:
E85 is scarce. About 150 stations sell it in 20 states, but that number is rising, and flex-fuel cars run fine on unleaded gasoline or gasoline containing 10% ethanol.
Biofuels may not be sustainable. Some scientists calculate that ethanol contains less energy than the amount of energy used in making it; growing corn for ethanol uses a great deal of tractor fuel and fertilizer, which often is made from fossil fuel. If they are right (and the debate is heated over this point), the more ethanol we use, the worse our fuel situation actually becomes.
Lower mileage. Ethanol contains about 30% less energy per gallon than gasoline. According to the Department of Energy (DOE), a 2006 Ford Taurus gets 27 mpg on the highway with gasoline and 20 mpg on E85. But Gary Schmitz, spokesman for the National Renewable Energy Laboratory, notes that fuel prices inevitably change. "If we project higher gasoline prices, and gradually declining ethanol prices ... in the future, ethanol will be a viable option" in terms of price, he says.
Interest in ethanol certainly is fermenting at the federal government. The DOE has embarked on a "billion tons of biomass" project to multiply the supply of biomass from farms and forests. And in March, the DOE "committed to build the first commercial ... plant," to make ethanol from cellulose, says Schmitz. Ethanol presently comes from corn grain, he adds, but the DOE wants to "use corn stover; things that are now plowed into the ground."
Blending biodiesel
While the biofuel ethanol traditionally has been made by corporate giants like ADM (Archer Daniels Midland), biodiesel was a product of small fry. Indeed, a favorite raw material was restaurant grease, which can be refined into a biodiesel that burns with a whiff of French fries, fried fish, even egg rolls. (Larger biodiesel refineries generally use soybeans as a feedstock.) Biodiesel burns in any conventional diesel vehicle.
Ethanol cuts emissions of carbon monoxide and carbon dioxide.
Biodiesel is getting attention from country-music legend Willie Nelson, who is pushing "Biowillie" at some truck stops. Nelson, a small-farm advocate, notes that biodiesel could strengthen the American farm economy while petroleum fuels serve as a siphon for exporting American dollars.
Biodiesel has advantages over conventional diesel, which biodiesel advocates sometimes call "dino-diesel." Plant-derived diesel lubricates engines better than some new low-sulfur dino-diesel fuels. Biodiesel is less flammable, and thus safer to handle. It biodegrades faster, so spills are less likely to pollute groundwater. It makes less soot and no sulfur oxides, a key cause of acid rain. And biodiesel produces fewer of the organic compounds that form ozone, a major lung irritant.
Biodiesel often is mixed with conventional diesel into a blend called B20 (with 20% biodiesel). Either B20 or pure biodiesel can fuel a standard diesel engine, and biodiesel recently has received federal certification as motor fuel.
Home & Family Resource Center could not find firm data on mileage from biodiesel, but a test in school buses in Kentucky found no change in mileage after changing from conventional diesel to B20.
July 24, 2006
|