A recent headline caught my eye, “Wind farms make climate change WORSE: Turbines actually heat up local areas.” This appeared in the London, England based Daily Mail. The article reported that air temperatures around four of the world’s largest wind farms had incresed over a decade by 0.72 degrees Celsius ( about 1.3 degrees Fahrenheit). It went on to provide a comparison to global temperature rise stating that Earth’s average temperature comparably had warmed by only 0.8 Celsius since 1900. Fox News picked up the article with its own headline, “Wind Farms are Warming the Earth, Researchers Say,” It therefore implied that wind farms were contributing to global warming. Is this good scientific analysis or an anti-wind farm statement?
Measuring local temperatures in a few specific areas, whether near wind farms, or near coal-fired power plants, does not provide evidence that wind farms or coal-fired power plants contribute to global warming, cooling or global anything. What is actually being measured is the local impact of machinery in operation and the movement of air caused by rotating blades that affects circulation in the immediate vicinity. Waste heat from a wind turbine has to go somewhere. Air currents are affected by turbines and may alter local ground temperature conditions either by making them warmer or cooler. (We’ll say more about this later.) On the other hand CO2 from coal-fired power plants does contribute to rising CO2 levels in the atmosphere and there is a direct correlation between global warming and elevated atmospheric CO2.
The original research that led to these screaming headlines comes from State University of New York – Albany where researchers conducted a study analyzing satellite data from 2003 to 2011 over large wind farms in Texas. The researchers concluded that wind farms were contributing to local warming of the air at ground level. The researchers stated that if these wind farms were even bigger they could impact local weather and climate. The operative word local should be noted.
It is worthwhile to compare this study to another reported in December 2010 in Discovery News in an article entitled “Wind Turbines Increase Crop Growth.” A University of Colorado study, as reported in this article, concluded that wind turbines improve the growth of nearby corn and soybeans by keeping the crops dry and reducing temperature extremes. The increased air movement caused by the turbines cools the crops just as a fan makes air feel cooler in a room on a hot day. The article stated that wind turbines are like trees in that they modify local weather conditions. I suspect that the Daily Mail and Fox News will soon provide us with a headline that states, “Trees Contribute to Global Warming – We Need to Cut Them Down.” The truth is that any time you operate machinery its emits heat. Put a lot of it in an area and the air heats up. Operate a fan in a room and it changes air flow which moves warm and cool air around. How difficult is this to understand?
Finally it should be stated that wind farms represent a renewable energy source making it possible to rely less on fossil fuel burning, CO2 emitting power plants for our energy needs. Whereas we know that rising CO2 correlates to rising temperatures on a global scale.