Saturday, May 19, 2007

Water Use by Ethanol Plants: Potential Challenges

Water Use by Ethanol Plants: Potential Challenges

Written by Dennis Keeney, Ph.D., Senior Fellow and Mark Muller, Director, Environment and Agriculture Program. Institute for Agriculture and Trade Policy, October 2006.

Ethanol production using corn grain has exploded in the Upper Midwest. This new demand for corn, and the new opportunities for value-added processing and cattle production in rural communities, has created the best economic development opportunity in the Corn Belt states in a generation or more. Ethanol demand has increased rapidly recently because of favorable economics of ethanol vs. gasoline, and the need for a performance enhancer to replace MTBE (methyl tertiary-butyl ether)in gasoline. Ethanol’s growth has been so dramatic that there are now concerns about the amount of corn available to meet various demands, including food, animal feed and export.

Overall, with increased research and investment in the industry and the potential for energy-efficient cellulosic material to displace corn as the primary feedstock, the environmental footprint of ethanol is expected to markedly diminish. However, one of the most important emerging concerns is the consumptive use of water. Consumptive use of water is broadly defined as any use of water that reduces the supply from which it is withdrawn or diverted.

As would be expected, most ethanol plants are being sited in the Corn Belt. Many of these regions are also experiencing significant water supply concerns, particularly in the western portion of the region. Minimal data is available on groundwater depletion, and the scope of future water availability is not clear. It will be to the benefit of the ethanol industry, and rural development initiatives in general, to get more clarity on the relationship between ethanol production, water consumption, and impacts on water supplies. Otherwise, shortage of water could be the Achilles heel of corn-based and perhaps cellulose-based ethanol


No comments: