NAS on Wind Farms
Matthew L. Wald has a story in May 4's New York Times entitled "Wind Farms May Not Lower Air Pollution, Study Suggests." The subtitle is: "A new report says that wind-generated electricity can probably not reduce smog and acid rain but may slow the growth of heat-trapping gases."
Building thousands of wind turbines would probably not reduce the pollutants that cause smog and acid rain, but it would slow the growth in emissions of heat-trapping gases, according to a study released Thursday by the National Academy of Sciences.
The committee concluded that use of wind energy to generate electricity probably would not significantly reduce emissions of two other pollutants, sulfur dioxide and nitrogen oxides, because current and expected regulations of these are largely based on cap-and-trade programs. The degree to which emissions would be further reduced through special provisions to encourage wind-energy use -- such as set-asides, in which a percentage of emissions allowed under the cap are retired to the extent they can be offset by wind energy -- is uncertain, the committee added.
Though there are caps on these 2 pollutants, I have to think that increasing wind power will allow us to reduce those caps more quickly than if we continue ramping up coal production. The less coal we burn, the cheaper it is for industry to abide by lower caps - therefore nasty emissions will decrease.
As for a popular anti-wind claim, that the turbines kill birds and bats,
Wind facilities can have certain adverse environmental effects on a local or regional level, by damaging habitat and killing birds and bats that fly into turbines. Among birds, the most frequent turbine fatalities are nocturnal, migrating songbirds, probably because of their abundance, the report says. However, the committee saw no evidence that fatalities from existing wind facilities are causing measurable changes in bird populations in the United States. A possible exception is deaths among birds of prey, such as eagles and hawks, near Altamont Pass, Calif. -- a facility with older, smaller turbines that appear more apt to kill such birds than newer turbines are.
Too little information is available to reliably predict how proposed new wind projects in the mid-Atlantic highlands would affect bird populations, the report says. As for bats, turbines placed on ridges -- as many are in the mid-Atlantic region -- appear more likely to kill them than turbines sited elsewhere. In fact, preliminary information indicates that in the mid-Atlantic highlands more bats are killed than expected based on experience with other regions, the committee said. Although scarce data make it hard to say how these deaths affect overall bat populations, the possibility of population effects is significant, especially if more turbines are added, given a general decline in several species of bats in the eastern United States.
Note the results - birds are not impacted outside of one area in California and there is not yet enough evidence (especially on modern turbines) to judge the effect on bat populations.
This study did not look at offshore wind - which may soon be a significant contributer to electricity production. Between Cape Wind in Massachusetts (468 MW) and Texas (at least 150 MW), major offshore wind farms will soon be a reality.
The important thing to remember is that wind power will play a role in the future but it must be coupled with things like energy efficiency and reduced consumption in order to actually decrease greenhouse gas emissions rather than merely slowing the rate of increase.