In the mid-2000s, ethanol was hyped as the panacea that would end U.S. reliance on foreign oil, bring jobs to the Great Plains as well as the industrial cities and reduce emissions of harmful pollutants and greenhouse gasses. That was soon deemed too optimistic by most impartial observers because of a number of significant problems inherent in the fuel and the production process it takes to get that fuel to market at scale.
A gallon of ethanol contains one third fewer BTUs than a gallon of gasoline, making it a less powerful fuel by volume. This results in lower mpg, more fill-ups and more miles driven to refuel. Corn ethanol is also energy intensive throughout production, and although the Environmental Protection Agency estimated a net energy gain (the amount of energy derived from the necessary input energy) of 5.9 percent, that study was widely criticized as underestimating input energies from facilities, refining equipment and machinery.
U.S. government incentives to producers of corn intended for fuel use exerts upward pressure on food prices overall, which has a regressive impact across the income spectrum in the U.S. and a disastrous impact on poor populations in places without arable land. Additionally, farmers cash in on the market pressure of corn farming for fuel by converting fields previously used for other food production.
The largest-scale source of ethanol production in the United States is corn. Other advanced procedures that develop fuel from cellulosic sources such as switchgrass do not yet have the technology or the infrastructure to produce at scale. Farming corn is water intensive and contributes more to soil erosion than other crops. Farming corn for fuel also incentivizes overworking the soil, leaving it less nutrient dense and less valuable for food production later. Ethanol production also uses more water in the refining process than other fuels, and most of the energy used in the farming, transporting and refining stages comes from fossil fuels.
