Sunday, July 24, 2005

"Going [Nowhere] With The Wind"

To the editor, Tom Paine:

In "Going With The Wind" (July 21), George Sterzinger [executive director of the Renewable Energy Policy Project] writes, "Every kWh of wind avoids on average 1.3 pounds of CO2 emissions from natural gas generation and is therefore at least a step towards a prudent climate stabilization policy."

There are a number of unmentioned considerations in this example that mitigate wind power as "prudent."

According to the Lawrence Livermore National Laboratory, natural gas is the source of only about 21% of our CO2 emissions and only about 25% of that fraction is from generating electricity. Replacing that 5% of emissions would indeed be slightly significant. According to the Energy Information Agency the electricity used from natural gas in 2002 was 691 TWh. The electricity from wind power was about 5 TWh, with an installed capacity of about 4,480 MW in 2002. The amount of wind power, therefore, to theoretically displace the 5% of CO2 emissions from natural gas burned for electricity would be almost 620,000 MW, requiring more than 48,000 square miles of newly industrialized landscape.

Even then, however, perhaps a third of the time, as in Searsburg, Vermont, the wind turbines would not be producing any electricity at all; in any case, because of the cubic relationship between wind speed and production, two-thirds of the time they would be producing at far less than their average rate -- so other sources, i.e., just as many fossil and nuclear plants, would still have to be operating as before. And because they would have to be run less efficiently to respond to the variability of the wind, their emissions might even increase.

categories:  ,