The facts about wind turbine sound

By JOHN DUNLOP

Last update: October 11, 2009 - 9:31 AM

Minnesota is one of the 10 windiest states in the country. It pioneered the new wave of wind power development in the 1990s. Today, it is the state that generates the largest share of its electricity from wind (7.48 percent in 2008, according to American Wind Energy Association), and it ranks fourth in installed wind-power generating capacity, after Texas, Iowa and California. Nationally, wind power has become one of our economy's mainstream electricity sources, accounting for 42 percent of the generating capacity added last year to power homes, offices and businesses. Yet it seems that when new wind farms are proposed, questions are still sometimes raised about the potential impact. We welcome the opportunity to set the record straight, based on the widespread experience that communities and the wind energy industry now have in the United States and across the globe.

Wind turbine sounds are no different from other sounds present in a suburban or urban environment. The sound of a turbine is mainly due to the aerodynamic swish of the blades rotating in the air.

Turbines can also emit some low-frequency sound. Acoustical experts agree there is no evidence that such sounds, which are emitted by a variety of sources, could be harmful to health -- indeed, if these levels were so harmful, urban dwelling would be impossible.

In short, turbine sound is quieter than many ambient sounds and is equally safe, and while some people may be disturbed by even a relatively quiet sound, the reality is that thousands of turbines have been successfully integrated with communities throughout the country.

Wind turbines are one of the most environmentally benign forms of electricity generation and allow most preexisting land uses -- typically ranching and farming -- to continue as before. As many farmers nationwide can attest, cows graze up to the foot of the turbines and on some days even use them for shade. Wind turbines safely operate on schoolyards.

Because turbines operate in so many locations and circumstances, the industry believes setbacks are best assessed on a case-by-case basis. Many permitting agencies have, however, established minimum required setbacks from residences, public roads and adjacent property lines. In instances where no required setbacks have been established, developers will work with local stakeholders during the siting and design phase of a project to determine what's appropriate.

Lights are needed on wind turbines to ensure air traffic safety under Federal Aviation Administration standards. The industry has worked with the FAA to develop guidelines aimed at reducing the number of lights while maintaining air safety. Typically, lights on the turbines around the perimeter of a wind farm will be sufficient.

As our economy grows and as we become ever more dependent on electricity for a range of uses, it's clear that our electricity must come from somewhere. Some of the best winds in the world blow across the American landscape, and installing wind turbines is an efficient way to capture that energy.

A report released just last year by the U.S. Department of Energy confirmed that wind power could generate 20 percent of the nation's electricity by 2030 -- a share as large as that of nuclear power today -- and that this level is not a limit. The report found no technical or macroeconomic barriers. The economic benefits alone include more income for landowners (and thus for communities) and more stability in electricity prices as a larger share of our electricity becomes immune to the impacts of fuel price volatility.

We invite people to stop at a wind farm to see and hear for themselves. You can find projects along Interstate 90 south of Rochester and further west, in southwestern Minnesota northwest of Worthington, or in numerous other spots around the country. Stop, shut off the car, get out, look and listen. You'll hear the gentle swoosh of the blades and see the power of wind in action.

Wind turbines are indeed a change in our landscape. They are the symbol of our clean and healthy energy future.

John Dunlop is a senior project engineer with the American Wind Energy Association.

Recent Commentary stories

Susan Reimer: Behind every philandering man, a willing woman - October 11, 2009

Susan Reimer: Behind every philandering man, a willing woman - The former never learns -- but what could possibly motivate the latter? More

Comment on this story | Read all 25 comments | Hide reader comments

New ideas for the public sector

THERE'S NEVER BEEN A BETTER TIME to create a more efficient Minnesota. Facing large budget deficits at the state, county and local levels, Minnesotans are seeing with new clarity that the public sector must adapt to new economic realities. Only the smartest, most strategic reinvention will ensure that our tax dollars are spent on the best programs and services. Read more

About Opinion Exchange

Opinion Exchange is produced by the Editorial Department, which is dedicated to hosting the discussion on a range of issues of interest to Star Tribune readers online and in print. In its new format, it's our hope that Opinion Exhange will create a more dynamic dialogue between Star Tribune readers and the Editorial Board. Many individual posts will be written and signed by members of the Editorial Board and will reflect their own opinions. Daily editorials will continue to represent the institutional voice of the newspaper and be researched and written by the Editorial Department, which is independent of the newsroom.

Subscribe to RSS|Learn more about RSS