Friday, March 28, 2008

Wednesday, March 19, 2008

They May Not Use Gasoline, but They Sure Burn Through Water

I think we need to probably change our lives (ride our bikes, walk more) to really make global change, just consuming different kinds of energy will not work!   This is an interesting look at something I haven't thought about with electric cars and makes my point:

http://www.nytimes.com/2008/03/18/science/18obelec.html?ex=1363665600&en=975260031e904abc&ei=5088&partner=rssnyt&emc=rss

They May Not Use Gasoline, but They Sure Burn Through Water
Published: March 18, 2008
Peter DaSilva for The New York Times
One way to reduce the world’s dependence on oil is to produce more cars that get their power from the electrical grid rather than the gas pump. In the United States, replacing a large percentage of the roughly 235 million cars, light trucks and sport utility vehicles with all-electric vehicles and plug-in hybrids (which have a supplemental gasoline engine) would make a big dent in gasoline consumption, currently about 380 million gallons a day.

Adding more plug-in vehicles would mean a sharp increase in water use.
But such a shift would have an impact on another of the world’s precious liquids water.
It takes a lot of water to produce electricity, both to mine and to process coal and other fuels and to cool power plants. Production of gasoline uses water, too, but in an analysis in the journal Environmental Science and Technology, Carey W. King and Michael E. Webber of the University of Texas found that adding more plug-in vehicles would result in a significant increase in water use because of the additional electricity that would have to be generated.

For every mile driven by a gas-powered vehicle that is displaced by one driven by an electric vehicle, the researchers report, about three times as much water is consumed (that is, lost to evaporation) and about 17 times as much is withdrawn (used and returned to its source).

The researchers say the impact on water use does not mean a shift to electric vehicles is a bad idea. But they say the impact would be severe enough, particularly in areas like the Southwest, that it should be considered in policy discussions about widespread use of electric vehicles.




Thursday, March 06, 2008