An approximate 40% increased energy return per gallon of ethanol over per gallon of gasoline is being claimed by numerous environmental groups and government organizations in efforts to save the environment from humans, all serving to fascinate me. How was this number arrived at? To account for only three major processes in ethanol production through farming machinery use, delivering a viable crop, and creating liquified alcohol based bio-fuel like ethanol requires increased fossil fuel use. Ethanol is also made of edible cash crops such as corn. Burning ethanol can be seen as literally burning away a food harvest.
David Pimentel of Cornell University and his colleagues offer ‘net energy’ as a simple measure of the viability of any fuel. Pimentel defines net energy as the fuel's heating value minus the sum of all the fossil energy required to produce the fuel, alternative fuel or not. Basically, to produce one gallon of ethanol requires use of more than one gallon of fossil fuels such as gasoline. To illustrate the point, it takes approximately 29% more fossil fuels use to produce and use one gallon of ethanol than one gallon of gasoline.
Burning a ‘clean’ alternative energy fuel that requires more fossil fuel energy to make than returned is not economical, environmentally beneficial, or the answer to U.S. energy needs and reduced CO2 emissions. This argument is not one of dollar expense only, rather one pleading that fossil fuel use rises with ethanol production. If Americans will pay more for an environmentally ‘friendly’ fuel, first the fuel has to be environmentally ‘friendly’ in production, with decreased use of fossil fuel based energy.
Actually using ethanol mixed with gasoline in a internal combustion engine is one major ethanol use issue. Ethanol can be seen as a viable low (stress low) blend fuel component for gasoline powered engines according to the American Petroleum Institute. Ethanol does burn more efficiently than gasoline, yet has far less lubricating properties than gasoline. This requires the blending of ethanol and gasoline. Friction on moving metallic engine parts alone rapidly increases wear, shortening the life of engines. Add in ethanol affects to engines such as component rusting and clogging and continued CO2 emissions from the blended fuel and ethanol becomes far less attractive to consumers.
The Renewable Fuels Association’s call for approval of E12 blends containing 12% ethanol mixed with gasoline is pushing the limit of blended fuels. Engines affected by ethanol blends are far from limited to personal passenger vehicles, numbering in the hundreds of millions. From massive generators to a gasoline powered lawnmower, ethanol is simply not suited for current operational requirements of most fossil fuel powered engines unless blended; when blended beyond 12% ethanol is risky according to the API and other sources. Plainly, ethanol as a bio-fuel has not provided substantial advantages in reducing CO2 emission.
Many brave souls question the wisdom in burning nutrient rich food for fueling a suburban work commute. Creation of ethanol requires the use of existing and expanded farm lands domestic and international. Food prices increase in 2008 when existing farm lands were devoted to growing bio-fuels, subsidized by U.S. tax dollars. Even the Willow tree touted as a better renewable energy bio-fuel source than corn and sugar cane requires growth time and human management.
If all the faults of ethanol are taken in stride by any organization it is the U.S. government. The Federal government offers massive tax incentives and support of carbon credit schemes for use of ethanol in place of other fossil fuels. Little to no consideration is given to the increased use of fossil fuels to produce ethanol. Bio-fuels are a politically advantageous topic for many politicians at this time. The last source to reference for the disadvantages and advantages of ethanol is the federal government. Federal agencies have received massive increases in funding to examine bio-fuels. Putting the bio-fuel options on hold for improved technology and further research would cease the need for massive economic and infrastructure change. Patience or reduced funding is not in the government's interests. Various watchdog groups relate that ethanol use would have long died had federal incentives not been offered. Private groups promoting and profiting from ethanol use are better sources for bio-fuel fact and fiction. As always, buyer beware, as not all eco driven trends will remain trendy.