Ethanol: How the Fuel is Produced, Growing Corn and Other Feedstocks, and More
Switchgrass and other sources of cellulosic ethanol
Moving forward, cellulosic ethanol has the potential to make ethanol a much more energy-efficient fuel, with yields that about double what the starch-based processes yield today. Because every plant contains cellulose, a huge variety of feedstocks -- some that would otherwise be wasted, like corncobs, straw or sawdust -- could be used. Switchgrass (pictured at left) is one such feedstock, and was thrust into the energy spotlight when it was mentioned in President Bush's 2006 State of the Union address. It grows eight or nine feet tall and is native to the US. Generally, it's very hearty and will grow in nearly any climatic variation, from the Gulf Coast into Canada. As a crop, it has a very high yield per acre (five to tens tons) with little use of pesticides, and a low production cost, which are two keys for economical production of alternative fuels. However, until very recently, the cost for producing cellulosic ethanol has been prohibitive, and the process has yet to hit mainstream ethanol production.
More ethanol information
Read more about ethanol at How Stuff Works, and check the American Coalition for Ethanol and the US Department of Energy's Energy Efficiency and Renewable Energy Alternative Fuels Data Center entry for ethanol.
More ethanol reading in TreeHugger
Here at TreeHugger, it's been a hot topic of discussion; we've covered rice-based ethanol, noted that America is drunk on the stuff, checked out a car conversion kit and pondered the life cycle impacts of both ethanol and biodiesel. We even got the Car Talk guys to weigh in on the efficiency debate.
Distill more green goodness with our Green Basics column, which appears regularly here at TreeHugger.