Commentary by
Peter Maldonado
RENEW Wisconsin
September 25, 2009

A document released by the wind opposition group Coalition for Wisconsin’s Environmental Stewardship (CWESt) claims to find a cause-effect link between wind turbines and reduced property values, but the self-described study fails to provide significant statistical data supporting its contention. The document, titled “Wind Turbine Impact Study,” also contains a “literature review” that turns out to be nothing more than a Google search trawling through opposition web sites for subject matter.

Given CWESt’s opposition to expanding wind generating facilities in Wisconsin, one can understand the organization’s decision to release a preliminary draft of this paper only a few days before the Legislature’s vote on Senate Bill 185, a bill directing the Public Service Commission to develop uniform permitting standards for wind energy systems. As stated in the cover page, the author, Appraisal Group One (AGO), specializes in “forensic appraisal, eminent domain, stigmatized properties and valuation research.” Our aim here is not to criticize the stated purpose of the report, merely to assess the validity of its methods and results. As the old adage goes, “garbage in, garbage out.”

The first part of the study is an opinion survey of realtors including salespeople, brokers, appraisers, and land developers. The study lists the number of titles represented, not the actual number of people surveyed, and therefore the number sounds inflated. “Licensed Real estate salesperson” comprised the largest group at 34, yet a later figure shows that only 18 respondents actually listed and sold a property with a view of turbines. This survey records every realtor’s opinion on this matter even though only half of them have had direct experience with properties near wind turbines.

The problem posed by a sparse sample size has a more profound effect on the ensuing study of property values. The paper looks at transactions near the Blue Sky Green Field (Fond du Lac County) and Forward (Fond du Lac and Dodge counties) wind farms and compares them with areas without wind turbines. Curiously, Alliant’s Cedar Ridge project was not assessed due to lack of data, so the paper states, even though that project also went on line in 2008. There were only six sales of properties recorded within the area of each wind farm. AGO’s graphs point out how far below the curve the values of the properties within the wind farm are, but six is hardly a significant number to sample. The samples of out-of-area sales that form the curves for Blue Sky Green Field and Forward are small in their own right (62 and 28, respectively). Compare those small data sets with the 811 transactions within Kewaunee County alone that factor into the forthcoming Lawrence Berkeley National Lab (LBNL) analysis at ten different sites nationwide.

The final section, the literature review, attacks wind turbines from all angles, straying from the paper’s ostensible purpose of analyzing property values. In a nutshell, this section surveys a broad range of impacts, including health, safety, wildlife, land use, quality of life, technological performance, tax policy and local economic effects. We tried an experiment and found that most of the bibliography contents can be located by using Google and searching for “property value impact wind turbine.” Not surprising, most of the web sites that appear in the search results are operated by groups opposed to wind development, presumably to support additional restrictions on windpower development. Nearly all of the citations can be found on these websites. To the extent the references include studies that were not negative to windpower development, they are dismissed in the CWESt paper as examples of propaganda underwritten by the wind industry. Moreover, one of the studies that found no significant impacts was brushed off as a masters thesis of an environmental science graduate student, a detail that might lead a reader to question the credibility of the source material.

As it turns out, the graduate student in question is Ben Hoen, whose novel and methodologically rigorous study of wind turbine impacts in New York state took into account viewshed effects. This approach is one of three tests incorporated in the aforementioned LBNL study. One line of research examines to what effect distance from turbines may have on property values after the facility was constructed. Another compares viewshed impacts on home sales and property values. The third test attempts to detect nuisance effects on property values. Expected to be released later this year, the LBNL report shapes up to be the most rigorous study on the subject of property values and wind turbines. Compared with the robustness of this forthcoming report, bolstered by 811 transactions in Wisconsin, the CWESt paper is weak tea, light on data and lacking in scientific integrity. Even though the data collection and analysis process is complete, LBNL will not publish its report until its findings have been thoroughly peer-reviewed. Until CWESt’s paper goes through a similarly rigorous review process, its findings should be taken with a grain of salt.

Peter Maldonado is a volunteer for RENEW Wisconsin, a sustainable energy advocacy organization. Peter holds a B.A. in Environmental Policy from Lawrence University. These commentaries also posted on RENEW’s blog: