Apparently ethanol and water don’t always mix, and local residents are taking sides, according to a report from The Economist.
Officials in Tampa, FL, got a surprise recently when a local firm building the state’s first ethanol-production factory put in a request for 400,000 gallons a day of city water. The request by U.S. Envirofuels would make the facility one of the city’s top 10 water consumers overnight, and the company plans to double its size. However, Florida is suffering from a prolonged drought. Rivers and lakes are at record lows and residents wonder where the extra water will come from.
They are not alone. A backlash against the federally financed biofuels boom is growing around the country, and "water could be the Achilles heel" of ethanol, says a report by the Minneapolis-based Institute for Agriculture and Trade Policy.
The number of ethanol factories has almost tripled in the past eight years from 50 to about 140. A further 60 or so are under construction. In 2007 President George Bush signed legislation requiring a five-fold increase in biofuels production to 36 billion gallons by 2022.
Ethanol is controversial with the general public for several reasons, including doubts of how green ethanol really is and that using farmland for ethanol pushes up food prices internationally. However, one of the least-known but biggest worries is ethanol’s extravagant use of water.
A typical ethanol factory producing 50 million gallons of biofuels a year needs about 500 gallons of water a minute. Most of that goes into the boiling and cooling process, which is similar to making beer. Some water is lost through evaporation in the cooling tower and in waste discharge. All this is putting a heavy burden on aquifers in some corn-growing areas.
Residents went to court in Missouri to halt a $165 million facility being built by Gulfstream Bioflex Energy LLC. The facility was projected to draw 1.3 million gallons of water every day from the Ozark aquifer. Projects are being challenged in Minnesota, Iowa, Nebraska, Kansas, and in central Illinois, where eight ethanol facilities are situated over the Mahomet aquifer. Demand for corn is such that more land is also being plowed up in drier regions of the Great Plains states to the west of the Corn Belt, where irrigation in required, increasing water demand further.
The good news is that ethanol plants are becoming more efficient. They now use about half as much water per gallon of ethanol as they did a decade ago. New technology might be able to halve the amount of water again, says Mike Fatigati, vice president of Delta-T Corp, a Virginia company which has designed a system that does not discharge any waste water. But others are skeptical. "There are things you can close loop [i.e., recycle efficiently] and things you can’t," says Paul Greene, a senior director for biofuels with Siemens Water Technologies, designers of the water-purification technology used in ethanol factories.
(Source: The Economist)
