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Iowa is the nation’s largest producer of corn ethanol

Iowa, sitting in America’s corn belt, has been the largest corn producer of any state for year after year.1 Not surprisingly, it also has the nation’s largest production capacity for corn ethanol,2 and according to the Iowa Corn Growers Association, the two billion gallons Iowa produced in 2007 led the nation.3 This is further supported by the federal Energy Information Administration (EIA), which doesn’t publish state-by-state figures, but which does name Iowa as the biggest producer.4

In 2005, the federal government enacted a law that effectively mandates a minimum level of ethanol production.  Many proponents felt this would increase energy security, and reduce carbon dioxide emissions and the global warming already underway. The idea is that the carbon in corn ethanol comes from corn, so when it is burned, it is just returning the CO2 to the atmosphere that was recently absorbed by the growing corn plant.  According to this logic, corn ethanol should not increase atmospheric CO2 the way burning gasoline does — it is just a kind of recycling.

However, because of the energy required to make corn ethanol in the first place, and because of changes in land use that farming corn for ethanol may trigger, the case is not so clear—and some scholars argue that corn ethanol leads to more CO2 emissions, net, than just burning gasoline.

  1. USDA ERS Browse - Corn & Feed Grains.”
  2. Renewable Fuels Association. “Biorefinery Locations.”
  3. Iowa Corn Growers Association/Iowa Corn Promotion Board. Iowa’s Ethanol and E85 Facts, (PDF) September 16, 2008.
  4. Energy Information Administration. “EIA-819 Monthly Oxygenate Report,” March 12, 2009.


2015 Summer Review Several cities in the Western U.S. had their hottest summer on record.

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