On the eve of San Miguel Board of County Commissioners' vote on a wind farm policy, a Los Alamos National Laboratories engineer working on wind turbine design tried to dispel myths about the technology's drawbacks.
Curtt Ammerman addressed a large crowd at James A. Little Theatre last night to discuss the lab's effort, which he said complements Sandia National Laboratories' and National Renewable Energy Laboratories' work in this area. Ammerman said that New Mexico currently generates 1 percent of the nation's wind energy, but has the capability to generate 40 percent.
The information Ammerman presented is of particular interest in light of an ordinance being put to a vote in San Miguel County today. A final ordinance prescribing requirements for wind energy facilities will be put to a vote at the Board of County Commissioners meeting, after extensive public hearings were held last year. Some community members had argued that a proposed wind farm to be built by Invenergy, a Chicago-based company that has leased land on Bernal Mesa since 2008, should be a minimum of 3 miles from residences; the project may be sited as close as 1,500 feet from residences instead.
Ammerman said that at a distance of 300 meters from a wind turbine, the noise is comparable to a refrigerator hum (40-50 decibels). He also addressed concerns about the hazard wind farms pose to birds, citing research that shows that while wind farms kill approximately 110,000 birds per year, domestic cats kill 10 million, power lines kill 130 million, and buildings kill 550 million. Although wind turbine blades may not appear to be moving quickly enough to pose a threat to birds, the blade tips on a turbine with a 77 meter diameter rotor move at 180-200 miles per hour, he said. Ammerman said no similar research evaluating the threat wind turbines pose to bats is available.
Audubon New Mexico Vice President and Executive Director Karyn Stockdale tells SFR that wind farms on mesas pose particular risks to raptors, which is especially concerning for less-commmon species like Swainson's hawk and bald and golden eagles. However, Stockdale acknowledged that wind turbine technology has evolved to pose less risk to birds than it used to.
"There's a lot of things that the industry has learned over the years of how to reduce those impacts," Stockdale says. "As long as [Invenergy] is being cognizant of the impact to wildlife, we support it."
Ammerman said the reason modern wind turbines are so large (200 to 300 feet tall) relates to a physics equation: when the diameter of a rotor is doubled, the power it puts out is quadrupled. In addition, since wind speed is faster higher off the ground, taller turbines get hit with higher-speed air, which also translates into more power.