Water and Ethanol
New reasons to be suspicious of
OFFICIALS in Tampa, Florida, got a surprise
recently when a local firm building the state's first ethanol-production
factory put in a request for 400,000 gallons (1.5m litres)
a day of city water. The request by US Envirofuels
would make the facility one of the city's top ten water consumers overnight,
and the company plans to double its size.
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, said 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 fivefold increase in biofuels production, to 36 billion gallons by 2022.
This is controversial for several reasons. There are doubts about
how green ethanol really is (some say the production process uses almost as
much energy as it produces). Some argue that using farmland for ethanol pushes
up food prices internationally (world wheat prices rose 25% this week alone,
perhaps as a side-effect of
A typical ethanol factory producing 50m 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
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