Local Concerns: Property Values, Sound and Safety
The Sound of Wind Turbines
Many individuals are often concerned about the sounds that wind turbines generate. In reality, wind turbines generate about the same amount of noise you would hear from a kitchen refrigerator or a moderately quiet room.
Turbine sounds used to be a very serious problem for the wind energy industry. Some early-design turbines, built in the early 1980s, were extremely noisy to the point that it was annoying to hear them from as much as a mile away. The industry quickly recognized this problem and manufacturers went to work on making their machines quieter. Due to technological advances and pre-construction sound assessments, the sounds from wind turbines are no longer a serious problem.
Virtually everything with moving parts will make some sound and wind turbines are no exception. However, well-designed utility scale wind turbines are generally quiet in operation and the sound from such turbines is very low compared to that of road traffic, trains, aircraft and construction activities.
Below are some frequently asked questions about wind turbines and noise.
Is it healthy to live near wind farms?
The evidence says wind turbines are safe neighbors.
- 10,000+ wind turbines in North America
- Tens of thousands of people now live and work in proximity to these wind turbines.
- A small number of individuals have claimed that their health has been impacted by wind turbines,
- Surveys of peer-reviewed scientific literature have consistently found no evidence linking wind turbines to human health concerns.
The wind industry takes health concerns seriously. Any concern that wind turbines may impact someone negatively should be explored. For more on wind turbines and health see this fact sheet:
http://www.awea.org/pubs/factsheets/Wind_Turbines_and_Health.pdf
Q: What have manufacturers done to reduce the sound of wind turbines?
A: Manufacturers have taken numerous steps to reduce turbine sounds. Some of these initiatives include: creating “upwind” rotors, streamlining towers and nacelles, increasing the soundproofing in nacelles, making more efficient wind turbine blades that create less aerodynamic noise, and designing gearboxes specifically for quiet operation.
Q: What about small wind turbines for household or battery-charging use?
A: Small wind turbines tend to be louder than their larger counterparts. This is because the rotational speed of the blade tips is higher. Also, government and private industries have invested more funding into research to reduce the sounds emitted by larger turbines.
The manufacturer of a small wind turbine can provide you with information about its sound levels, based on standard measurement techniques.
Q: What other sounds are associated with large wind projects?
A: Large wind projects also produce sounds associated with construction. Trucks and heavy equipment are generally used for wind farm construction. Of course, construction activities that produce noises are often scheduled during business hours as not to disturb nearby residents.
Q: What can be done to reduce the likelihood of a noise problem from a wind project?
A: A sound analysis can be done based on the operating characteristics of the specific wind turbine that will be used, the type of terrain in which the project will be located, and the distance to nearby residences.
For more on sound see AWEA’s fact sheet here, http://www.awea.org/pubs/factsheets/Utility_Scale_Wind_Energy_Sound.pdf, and chapter 5 of the AWEA Siting Handbook
Wind Turbines and Safety
Modern wind turbines are safe. Utility-scale wind turbines are certified to international engineering standards, and include ratings for withstanding different levels of hurricane-strength winds and for other criteria. Agricultural activities can occur right up to the base of the turbine.
Modern wind turbines are so safe they successfully operate near schools, in urban settings and densely populated areas, and in rural communities. Blade throws occurred in the industry's early years, but are unheard-of today because of better turbine design and engineering.
Ice throw is of little danger. Setbacks typically used to minimize noise are sufficient to protect against danger to the public. Fundamentally, ice buildup slows a turbine's rotation and will be sensed by a turbine's control system, causing the turbine to shut down. Ice is not thrown, but may drop from a still wind blade as the ice melts.
Property Values – Will Wind Turbines Make a Difference?
There is no evidence that the presence of a commercial windfarm within sight of a property systematically decreases that property’s value. In fact, a nationwide study conducted in 2003 surveyed property near multiple wind farms and found that not only do wind farms not harm property values, but that in some cases the values increased.
Preliminary results from a new nation-wide study by the Lawrence Berkeley National Laboratory show no statistical evidence that homes within the wider area around a wind facility are affected adversely based simply on proximity. They also show no statistical evidence that homes with a view of turbines have different values than homes without. The final study is expected to be out in the Fall, 2008.
For a fact sheet answering questions about common myths around wind energy, see http://www.awea.org/pubs/factsheets/050629_Myths_vs_Facts_Fact_Sheet.pdf.
Additional fact sheets on a variety of topics may be found here: http://www.awea.org/pubs/factsheets.html. |
