Ethanol’s Not So Great
Ethanol, a growing industry in areas like the U.S. Midwest, uses massive amounts of water in the fermentation and cooling stages of production. According to the Minnesota Department of Natural Resources, an average of 4.3 gallons of water is used for every gallon of ethanol produced.
In the U.S., there are 16 ethanol facilities and another five under construction in Minnesota alone. In 2008, Minnesota’s annual ethanol production capacity will rise above one billion gallons. That yield will consume more than 4.3 billion gallons of water. Experts say that there’s a significant risk that the increasing ethanol production could suck regional sources of groundwater dry, a warning that has officials in and around the Midwest delaying or denying approval of permits for ethanol plants.
In Canada, the energy industry is facing a different water challenge. Oil sands extraction and production in Alberta more than doubled between 1995 and 2004, to 1.1 million barrels a day. Predictions have the region producing five million or more barrels per day by 2030.
The water-based extraction process for the tar-like oil sands uses between two and four barrels of water for each barrel of oil produced. The oil sands industry also uses large quantities of energy and produces massive amounts of wastewater and solids, known as “tailings.” Between surface and groundwater extraction, a five million barrel industry will use between 50 and 100 trillion gallons of water per day.
In the September/October issue of ReNew Canada, the national infrastructure renewal magazine, Curt Sparks says, “In contrast to the ethanol industry, the oil sands industry already practices significant reuse. Industry has long been, and must continue to be, a model for water reuse. But much more needs to be done to call industry practices sustainable.”