Because the environmental benefits of wind energy are significant, public support for expanding wind energy development is widespread. The impacts of wind projects, however, are predominately local and can concern some individuals in the affected communities and landscapes. A primary challenge in achieving 20% of U.S. electricity from wind by 2030 is to maximize the overall benefits of this form of energy without disrupting or alienating specific communities, especially prospective communities that do not have experience with wind turbines.
Wind energy development receives considerable general support among the U.S. population. Of those polled in a study conducted by Yale University in 2005, more than 87% want expanded wind energy development (Global Strategy Group 2005). Only a minority of the U.S. population appears to oppose wind energy, but that opposition can strengthen when particular sites are proposed. Some evidence indicates that, over time, opposition might decrease and support might grow. Surveys commissioned in the United Kingdom and Spain have found, for example, that local support for a wind project increased once it was installed and operating.
Communities must be consulted about the global impacts of wind, and this must include addressing their concerns early on. Involving affected communities early is critical to identifying concerns and addressing them proactively. Stakeholder concerns must be taken seriously, and a long-term commitment to understanding stakeholder interactions must be made.
Wind turbines can be highly visible because of their height and locations (e.g., ridgelines and open plains). Reactions to wind turbines are subjective and varied. The best areas for siting wind turbines tend to be those with lower population densities. Although this can minimize
the number of people affected, less populated areas may also be prized for tranquility, open space, and expansive vistas. Some people feel that turbines are intrusive; others see them as elegant and interesting. In either case, the visual impacts of wind energy projects may well be a factor in gauging site acceptability.
Discourse with communities about the expected impacts is important. Wind project developers can conduct visual simulations from specific vantage points and produce maps of theoretical visibility across an affected community (Pasqualetti 2005). With this information, a developer can make technical adjustments to the project layout to accommodate specific concerns, relocate wind turbines, reduce the tower height, or even propose screening devices (such as trees) to minimize visual impact. All of these steps can, of course, affect the economic feasibility of a proposed project, so they should be weighed carefully in siting and development decisions.
Because almost all commercial-scale wind turbines rise more than 60 m above the ground, proposed wind projects must be reviewed by the Federal Aviation Administration (FAA). In February 2007, the FAA updated an advisory circular (FAA 2007) dealing with obstruction lighting and marking, including new uniform recommendations for lighting wind energy projects. The new FAA suggestions are designed to allow pilots flying too low to be warned of obstructions and minimize intrusion to neighbors. The guidance recommends that wind energy projects should be lit at night, but now the lights can be up to 0.8 km apart and be placed only around the project perimeter, reducing the number of lights needed overall. The guidelines recommend red lights, which are less annoying than white lights to people nearby. No daytime lighting is necessary if the turbines and blades are painted white or off-white.
All machinery with moving parts make some sound, and wind turbines are no exception, though advances in engineering and insulation ensure that modern turbines are relatively quiet; concerns about sound are primarily associated with older technology, such as the turbines of the 1980s, which were considerably louder. The primary sound is aerodynamic noise from the blades moving through the air— the “whoosh-whoosh” sound heard as the blades pass the tower. Less commonly heard in modern turbines are the mechanical sounds from the generator, yaw drive, and gearbox. When the wind picks up and the wind turbines begin to operate, the sound from a turbine (when standing at or closer than 350 m) is 35 to 45 decibels. This sound is equivalent to a running kitchen refrigerator.
The primary asset for many families is their home, so property values are a serious concern. Residents can become particularly concerned about possible declines in local property values when wind energy projects are proposed in their community. To ascertain what effects they are likely to experience, they may look to other communities with existing wind facilities.
Studies of the effects of wind projects on local property values should be done with great care, even though extensive studies have already been conducted on other energy facilities, such as nuclear plants. Because home values are a composite of many factors, isolating the effects of proximity to a wind project is important (though only a part of the full picture). Wind projects also tend to be located in areas of low residential density, which further compounds the difficulties of controlling the impact on property value. To date, two studies have examined these issues in the United States. Though neither is definitive and additional work in this area is needed, both studies found little evidence to support the claim that home values are negatively affected by the presence of wind power generation facilities.
Individuals with turbines on their properties might actually see an increase in their property values because of the lease payments paid by the wind project owner. Lease payments tend to be $2,000 to $5,000 (US$2006) per turbine per year, either through fixed payments or as a small share of the revenue.
In 2003, the Renewable Energy Policy Project (REPP) conducted a study of 24,000 home sales surrounding 11 wind projects in the United States. It compared the average selling price over time of homes near the wind project with a nearby control area that was at least 8 km from the project. No clear evidence of adverse effects on property values was found. In some communities, home values near the facilities rose faster than properties in the control group (Sterzinger, Fredric, and Kostiuk 2003).
In April 2006 a Bard College study focused on a 20-turbine wind project in Madison County, New York. Researchers visited each home, measured the distance to the nearest turbine, and ascertained to what degree the home could see the wind facility. This study also concluded that there was no evidence that the facility affected home values in a measurable way, even when concentrating on homes that sold near to the facility or those with a prominent view of the turbines (Hoen 2006).