In his recent State of the Union address, President Bush advocated reducing U.S. gasoline consumption by 20 percent in 10 years: "20 in 10." This is a goal that could easily be attained through increased fuel economy standards. However, the Bush administration instead chose to focus on biofuel development to displace 15 percent (or 35 billion gallons) of our unchecked petroleum consumption. Unfortunately, the nation currently produces only a fraction of this much biofuel and environmental concerns are not being considered. Since Montana is poised to play a major role in biofuel development, we must take a good look before we leap.
To date the only significant biofuel infrastructure in the United States is corn grain ethanol. In 2006 we produced more than 5 billion gallons of ethanol (less than 3 percent of transportation fuel demand) from corn produced on 9 million acres prime farm land. That is a lot of corn, but not much fuel. Even if every single acre of corn in the United States were put into ethanol production it would only satisfy 14 percent of our projected fuel consumption.
The other major biofuel slated for development is cellulosic ethanol which is produced from logging residues and biomass crops. Cellulosic ethanol has a positive energy balance (about 5:1 units of ethanol per unit of fossil fuel), stores carbon, and can be produced from crops that actually protect soils. Unfortunately, cellulosic ethanol is not yet commercially available, thus the nation must go from near zero to 25 billion gallons cellulosic ethanol in 10 years.
Cellulosic ethanol requires a lot of biomass and thus a lot of land. It would take approximately 306 million tons of cellulosic biomass to produce 25 billion gallons of ethanol. If Montana supplied just 10 percent of this biomass from logging residues or grasses, then
3 million to 6 million acres of land in Montana would be employed in annual biofuel production. Interesting idea; however, only about 400,000 acres of timbered lands are currently harvested each year in the whole Rocky Mountain West. Furthermore, biomass can only be hauled about 50 miles economically, thus grass crops in Scobey or logging residues in Yaak may be an unrealistic endeavor.
The environmental impacts of cellulosic ethanol plants are unknown. Some potential impacts include: (1) Ethanol plants require about four gallons of water per gallon of ethanol produced (that's a lot of water in a dry state); (2) The use of crop or logging residues denies soils of carbon and nutrients; (3) Ethanol plants require a constant flow of biomass (will fuel demand drive timber harvest?).
Biofuels certainly hold an important a place in our country's fuel mix. However, in a nation that insists on driving large vehicles that average less than 21 miles per gallon, the production of grain ethanol at the expense of soil resources and in the face of increasing global populations is, at best, irresponsible. Cellulosic ethanol has a bright future, but source volumes and impacts must be scrutinized. As a society, it is our responsibility to learn to conserve fuel before we are entitled to the consumption of soil degrading fuels produced from food of fiber resources.
Tom DeLuca is a senior scientist with the Wilderness Society in Bozeman, specializing on issues in forest ecology, land resources and environmental sustainability.
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