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Bat deaths down at wind farm

The number of bats killed by wind turbines at the Spring Valley Wind Farm in 2014 has been reduced by more than 75 percent compared to the same time frame last year. According to Ely’s BLM Field Manager Paul Podborny the reduction comes as a result of changes put in place at the beginning of the year by the company that owns the wind farm, Pattern Energy.

“The mortality surveys that have been done to date this year recorded only 23 bat fatalities. In the same time frame last year, there were 103 bat fatalities recorded,” Podborny said.

After 533 bats were recorded killed by the wind turbines in 2013, tripling the amount allowed by federal regulators, Pattern Energy implemented new “cut-in” speeds for the turbines, increasing the wind speed required to spin the turbine from 7 mph to 11 mph.

Podborny met with representatives from Spring Valley Wind on Aug. 25 to see how effective the required changes had been. Though he will continue to monitor the fatality rate through the end of the year, Podborny said that this “mid-stream check” has shown the changes are working.

“It appears to be working so we are going to continue with the increased cut-in speeds for the rest of the year,” Podborny said. “Based on full-year data, then we will make a determination if we need to change anything more.”

The Spring Valley Wind Farm produces 152-megawatts of energy, enough to power 40,000 homes, which it then sells to NV Energy. Opened on Aug. 8, 2012, the wind farm houses 66 turbines, standing 425 feet tall. Environmentalists opposed the project before it opened for fear that its environmental impact, such as killing bats, would be too great.

The bats killed by the turbines are Mexican free-tail bats, which migrate by the millions through Spring Valley each year. No threatened or endangered bats have been killed.