Study finds wind farms have much higher environmental impact than thought

Wind farms are becoming common in many parts of the country, particularly those that commonly experience windy conditions- like the front range of Colorado. While green energy supporters claim that any impact to the landscape from ugly and gigantic farms of wind turbines is offset by the reduced environmental impact of coal and gas power generation, others disagree. A new study has found that the environmental impact of wind farms is higher than previously thought.

Details on the potential impact on the environment by wind farms were detailed in two papers published recently including one in Environmental Research Letters and one in Joule. Harvard researchers found that the transition to wind or solar power for the US would require as much as 20 times more land to meet requirements than previously believed. The studies also found that if these large-scale wind farms were built, they will warm average surface temperatures over the continental US by 0.24 degrees Celsius.

The data collected found that for wind power the average power density was 100 times lower than estimates by some leading energy experts. These experts arrived at such erroneous information by failing to consider the turbine-atmosphere interaction. Researchers claim that when considering a single turbine, this isn't an issue. However, when you are talking about wind farms more than 5-10km deep, the turbine-atmosphere interaction has a major impact on power density.

The scientists in the study based this on observation data rather than theory and proved that power density is much lower than important estimates from the US Department of Energy and the Intergovernmental Panel on Climate Change. The study also found that the average power density for solar energy is ten times higher than wind power. However, power density for solar energy is also much lower than estimates by leading energy experts.

The research suggests that wind farms will require much more land to hit proposed renewable energy targets and at the required sizes, the wind farms will themselves be an active player in the climate system. Researcher David Keith says that if you look at this over a decade wind power has more climate impact than coal or gas in some respects. However, looked at over the next thousand years wind power has "enormously less climatic impact than coal or gas."

SOURCE: Harvard