There is an article in the January - February Issue of
Foreign Affairs ("The New Petroleum", by Richard G. Lugar and R. James
Woolsey) which argues that, given some support, cheap ethanol produced from
"cellulosic biomass" (rather than feed grains, as at present) could
greatly reduce American reliance on fossil fuels and dependence on Middle East
producers. Part of the argument reads as follows:
Renewable fuels produced from plants are an outstanding way to substantially reduce greenhouse gases. Although burning ethanol releases carbon dioxide into the atmosphere, it is essentially the same carbon dioxide that was fixed by photosynthesis when the plants grew. Burning fossil fuels, on the other hand, releases carbon dioxide that otherwise would have stayed trapped beneath the earth.
If one looks at the complete life cycle of the production and use of ethanol derived from feed grains, the only addition of carbon dioxide to the atmosphere results from the use of fossil fuel products in planting, chemical fertilizing, harvesting, and processing. But this fossil fuel use can be substantial—up to seven gallons of oil may be needed to produce eight gallons of ethanol. When ethanol is produced from cellulosic biomass, however, relatively little tilling or cultivation is required, reducing the energy inputs. It takes only about one gallon of oil to produce seven of ethanol. There is a virtual consensus among scientists: when considered as part of a complete cycle of growth, fermentation, and combustion, the use of cellulosic ethanol as a fuel, once optimized, will contribute essenfially no net carbon dioxide to the atmosphere.
According to a1997 study done by five laboratories of the U.S. Department of Energy, a vehicle powered by biomass ethanol emits well under one percent of the carbon dioxide emitted by one powered by gasoline. More surprising, however, is that ethanol produced from biomass emits only about one percent of the carbon dioxide emitted by battery-powered vehicles, since the electricity for those is com-monly produced by burning fossil fuels at another location. Although local air quality is improved, total carbon dioxide emissions are not curtailed; they are merely exported—for example, from Los Angeles to the Four Corners. Unless the electricity to charge the car’s batteries is produced by renewable fuels or nuclear power, electric vehicles are only 20 to 40 percent better as carbon dioxide emitters than gasoline-powered cars. Biomass ethanol beats both by a factor of about 100, fundamentally changing the global-warming debate.
The authors further suggest enormous economic
benefits for declining agricultural areas as petroleum stocks decline and
efforts to find biomass based replacements intensify. Perhaps the
next back to the land movement will be based on economic reality, not
ideology?
A couple of interesting points: Brazil already has
3.6 million pure ethanol driven vehicles on the road, and (the authors
argue) Henry Ford saw ethanol as the fuel of choice for automobiles.
Ed Weick
