Agricultural land in the United States, generally that which is corn producing, is being converted on a large scale from food to biofuel production. Originally envisioned as a greener substitute for traditional fossil fuels, recent research has shown that biofuels actually have a larger carbon footprint than previously thought. Additionally, the reduction of American corn used for food has increased the price of food worldwide. The United States government continues to support increased biofuel production for national security reasons and to help sustain American agriculture. The result will be more land conversion to biofuels in the years to come (Westcott 2009).
Conversion of Corn Production from Food to Ethanol
From 2000 to 2008, corn used for ethanol rose from 6% of the total corn harvest to 24%, and is expected to exceed 30-35% by the next decade (Westcott 2009).Food prices have increased as a result of production shifting towards biofuels (Searchinger 2009a).
Only 8% of world ethanol and 12% of biodiesel are used outside of the country where they are produced, primarily due to tariffs and other restrictions (Searchinger 2009a).
Compared to traditional gasoline, the use of corn-based ethanol may emit as much as 93% more greenhouse gases over the next 100+ years, considering the entire lifecycle of ethanol production (Searchinger et al. 2008).
The Energy Independence and Security Act of 2007 will require 36 billion gallons of biofuel to be on the market by 2022, a dramatic increase from legislation passed only two years prior.To meet this goal, a continued expansion of American biofuels production will be required (Westcott 2009).
U.S. government subsidies and tax credits are two of the primary drivers of biofuel production in the US.Since 1978, Congress has passed numerous laws encouraging enhanced biofuel production on America's already heavily-subsidized farmland (Tyner 2008). The rationale for increasing biofuels production has been to reduce dependence on foreign oil with a renewable energy source, as well as to support America's farmers. The most recent law passed in 2007 is the aforementioned Energy Independence and Security Act, which will require an approximate 13% biofuel substitution of all transportation fuel by 2022 (Howarth et al. 2009a). The US government also phased-out and replaced the gasoline oxygenator Methyl Tert-Butyl Ether (MTBE) in 2005 with an ethanol product, which has increased ethanol demand drastically (Searchinger 2009a).
High fossil fuel prices have also increased the demand for American biofuels and other alternative energy sources.Insatiable demand from developing nations such as China and India has placed a major burden on the energy market, reducing supplies and driving up prices of fossil fuels. However, high fossil fuel prices can also raise grain prices, thereby damaging profits for the biofuels market. Government guarantees and incentives can ensure a more stable market (Searchinger 2009a).
World grain supplies are at their lowest levels since 1982 due to widespread conversion of corn from food production to ethanol.From 2006 to 2008, corn prices rose from $87 to $217 per metric ton. Increasing food demand from developing nations has also contributed significantly to these high prices (Fargione, et al. 2008, Tyner 2008).
Biofuels production may also produce significantly more greenhouse gases than traditional gasoline, if indirect land use conversions and soil types are considered.Biofuels were originally envisioned as a greener alternative to fossil fuels, but this perception may be flawed. In fact, when comparing the carbon footprints of ethanol and gasoline, ethanol may have up to a 93% larger footprint. Indirect land use conversions that are a result of the original conversion to biofuel production and the exploitation of marginal lands are likely to blame. (Searchinger et al. 2008). Even in the existing Kyoto Protocol of climate emissions reduction, there is no accounting for direct bioenergy emissions from smokestacks and tailpipes (Searchinger et al. 2009b).
Increasing ethanol use is driving direct land cover and land use change in the Midwestern United States.Agricultural acreage is increasing, and farmers are switching their fields corn production. The crop most affected by changing land use has been soybeans, which have dropped in acreage since the beginning of the ethanol boom in the mid-2000s, though cotton has also seen a considerable decline in acreage (Westcott 2007). Besides causing higher prices for soybeans, this land use change will also increase runoff pollution since corn requires large amounts of fertilization.
There are numerous other environmental problems which may be exacerbated by the production of biofuels in the central United States.Biodiversity loss, both in the US and abroad due to land use change, is a major risk. Fresh water will also be needed for irrigation of biofuels crops, further limiting an already finite and dwindling resource for many areas of the world. Water pollution due to fertilizer runoff will increase since corn is a particularly demanding crop to fertilize (Howarth et al 2009b).
Biofuel production in the United States is expected to continue growing.Congressional mandates, high oil prices, and the goal of energy independence are all driving this increase.
Based on available farmland, ethanol production will likely peak at around 57 million barrels per year, which is only slightly higher than the capacity at which current planned and constructed biofuel processing plants will be able to handle.Additional factors limiting ethanol producers are economical, whereby the price of food may be driven so high due to farmland conversion to biofuels production that even biofuels producers cannot afford to buy the crops (Howarth et al. 2009a, Searchinger 2009a).
If efforts are made in the US or EU to facilitate free trade of biofuels, production may also increase in the developing world. Currently, very little biofuel is traded on the world market due to tariffs, meaning the highest profits for Americans can be obtained by producing biofuels in the central US. However, production costs are much lower in developing nations, which could mean a global shift of ethanol production away from the central US to those areas if free trade of biofuels were to begin. While this may be advantageous economically, many of these nations are already struggling to feed their populations, a problem which may worsen if their farmland is changed to fuel production (Searchinger 2009a).
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