Wind power will fail to reduce carbon dioxide emissions as much as claimed by wind power advocates, concludes a recent study in the Renewable and Sustainability Energy Review, published by Elsevier. The study, “Why wind power does not deliver the expected emissions reductions,” adds to the growing weight of evidence that the intermittent nature of wind power causes backup conventional power generation to operate less efficiently—and thus produce more carbon dioxide emissions per unit of power generation—than is currently the case.
Consistent Results in Several Nations
The study by Herbert Inhaber examines the real-world impacts of wind power on carbon dioxide emissions in several different nations. Inhaber, a Ph.D. physicist, is a former Senior Risk Assessment Expert at the Harry Reid Center for Environmental Studies at the University of Nevada, Las Vegas.
Inhaber includes data and analysis from wind power generation in Germany, Denmark, Ireland, Estonia, Colorado, Texas, and the U.S. Pacific Northwest. In each case, emission reductions were less, often much less, than forecasted by wind proponents, and in several, emissions reductions were zero.
A common theme among the different nations is that as the percentage of power provided by wind rises, the percentage of averted carbon dioxide emissions declines.
“As the proportion of renewable energy penetrating the electricity grid grows, the reduction of CO2 emissions drops sharply,” Inhaber told Environment & Climate News. “By the time wind power—and, by analogy, solar—reaches about 20 percent of the grid, the savings in CO2 emissions are negligible, of the order of a few percent.”
Like Stop-and-Start Driving
“[T]he reason for this finding can be found on the miles per gallon sticker on the windows of new cars. The mileage for highway driving is always greater than that for city—stop and go—driving. When we touch the brake pedal, we change the engine speed. The lower mileage for city driving means less efficiency from the gasoline and more pollution per mile driven,” said Inhaber.
“In the same way, when back-up electricity—mostly natural gas power plants—when the wind doesn’t blow and the sun doesn’t shine, is ramped up and down, there are more CO2 emissions compared to when the back-up is running full blast. Result: much of the emissions savings from using wind power or solar is lost,” Inhaber explained.
Tom Tanton ([email protected]) is principal of T2 & Associates, a California-based energy technology and policy consulting group.