The Lawrence Berkeley National Laboratory released a study this month that's bound to generate some controversy: its authors are saying they found no evidence that the presence of utility-scale wind turbines causes a drop in nearby resiidential property values.
The study, with the imposing title "A Spatial Hedonic Analysis of the Effects of Wind Energy Facilities on Surrounding Property Values in the United States," analyzed more than 50,000 real estate transactions in nine states involving properties within 10 miles of wind turbines. The authors say they found no evidence that home values were affected by nearby wind turbines, either during the planning and construction phases or after the turbines go into operation.
None of the properties examined were in California. Texas, which has the most extensive wind turbine infrastructure in the U.S., was also omitted from the study.
Of the nine states included in the study, all but Washington and Oklahoma are in the northeastern U.S. and upper Midwest; Minnesota, Iowa, Illinois, Ohio, Pennsylvania, New York, and New Jersey rounded out the survey area.
In case you're wondering, the word "hedonic" in the study title means "having to do with pleasure": the study was intended to analyze the degree to which the aesthetic influence of wind turbines affected people's willingness to buy homes near those turbines. The authors didn't take concern over the alleged health effects such as Wind Turbine Syndrome into account.
The study's results showed a small effect on values of homes that were very close to wind turbines, within a half mile or so. But that difference was smaller than the study''s margin of error, causing the study authors to decide they couldn't distinguish that effect from statistical noise.
Previous studies with significantly smaller sets of data had suggested that wind turbines might reduce property values for adjacent homes by around 3 or 4 percent.
Aside from geographical omissions, the authors of the study concede that there are potential sources of error in their work. For one thing, though wind turbine installations are burgeoning across the country, finding trustworthy data on home sales nearby and then determining what those sales might have brought had there been no nearby turbines was a daunting project. As a result of wind turbines often being placed in relatively unpopulated areas, only about two percent of the sales studied involved properties a mile or less from the turbines.
The authors also used a mix of prior sales and local tax assessment data to come up with a baseline for home values pre-turbine, which introduces a whole range of possible monkeywrenches: assessors don't always get things right, and people short-sell or overpay for homes for a range of personal, subjective reasons.
On the other hand, the authors did take pains to exclude sales of homes where tthe homeowner was also the owner of the turbine, judging that potential revenue from the turbine might provide a sales incentive that would unfairly skew the overall results upward.
While the study is the broadest on the topic to date, with a larger dataset than those that have preceded it, the authors do suggest that their sampling may obscure specific geographic factors that would affect home values in the vicinity of turbines. which essentially means that if we want data on how California wind turbines affect the value of California homes, we're going to have to look at data from, well, you know.