Misrepresenting turbine impacts on property values

Iberdrola Renewables' Deerfield Wind application proposes to erect fifteen 2-MW turbines in Searsburg, Vermont. During technical hearings before the VT PSB this month a host of important topics were explored and tested including wildlife impacts, turbine noise, economic benefits, and transmission constraints. Evidence was also presented on the possible impact of turbines on property values.

Deerfield Wind's "expert" on economic impacts, Thomas Kavet, asserted in written testimony that "there is no objective empirical data that supports the contention that there will be negative aggregate property valuation impacts at the town, county, or regional levels as a result of the proposed wind farm." Kavet boosts that he conducted an "extensive literature review" of the topic and cites three reports to substantiate his conclusion of no negative impact as follows:

  1. The Effect of Wind Development on Local Property Values by the Renewable Energy Policy Project (REPP) - May, 2003
  2. Impacts of Windmill Visibility on Property Values in Madison County, New York by Ben Hoen - April 2006
  3. Lawrence Berkeley National Laboratory report by Ryan Wiser et. al. - Not released

Windaction.org, a party to the Deerfield proceedings before the VT PSC, cross-examined Kavet on his testimony and revealed several important omissions in his analysis.

REPP Analysis:

Kavet characterized the REPP report as "extensive and particularly relevant on this topic" since the study included the Searsburg wind facility, an existing project adjacent to the proposed Deerfield site. Quoting from the REPP report, Kavet states "there is no significant evidence that the presence of the wind farms had a negative effect on residential property values" and that "average sales prices grew faster in the viewshed than in the comparable area" following construction of the wind turbines.

Kavet's review, however, failed to uncover the flaws in the REPP report and why its results have been widely criticized as "extremely weak, if not entirely misleading [Hoen]." Key flaws of the REPP report include a) the authors make no attempt to discern those properties in the study which have a view of the turbines from those with no view. In fact, sixty-six percent of the homes sampled in the REPP report do not see the wind facility at all; b) the REPP analysis makes no distinction between homes near the turbines and those five miles away thus assuming the effect of the turbines was equal on all properties regardless of proximity; and 3) the sales transactions studied in the REPP report included all transactions including those where the buyer, seller, or both may have been unwilling parties (divorce, estate sales, sales between family members).

Hoen Analysis:

Kavet praised Ben Hoen's analysis of property valuation changes associated with the Fenner wind facility (Madison County, NY) as "the most rigorous, unbiased study on this topic to date". Kavet quotes from the report as follows: "Contrary to the notion that adverse effects are universal, this report did not produce any significant relationship between distance from, or visibility of the windfarm and sale prices of homes." Although Kavet liberally applies Hoen's conclusions to the Deerfield project site, he omits one important point: Hoen's report makes clear that his analysis only applies to Fenner NY and communities similar to Fenner. Nowhere in Kavet's analysis does he raise this point nor does he try to justify how the Fenner study might apply to Searsburg, Vermont. 

Wiser Analysis:

Finally, Kavet hails the Wiser report as conclusive proof that properties are not negatively impacted by wind turbine development. He briefly acknowledges that Wiser's report has not been released yet, but that does not stop him from asserting: "There is no statistically significant evidence that views of wind turbines have a measurable impact on property resale values, even among properties in relatively close proximity to wind turbines."

In fact, Windaction.org is scheduled to be a reviewer of the Wiser report prior to its release. To date, all that's been circulated is a preliminary Powerpoint (PPT) presentation. In an e-mail correspondence between Ryan Wiser and Windaction.org (Oct 12, 2008), Dr. Wiser stated:

"Whenever we have given a [PowerPoint] PPT, we have carefully couched it as representing preliminary results that may or may not change. ...I have no real control over how our PPTs are being used and circulated. I would not personally distribute them widely, as I do not consider them the final word. That said, I am not surprised that others are using them, and I guess I have no real problem with it as long as it is couched as preliminary, intermediate findings; findings that may well change. Of course, I also understand that some wind developers may not offer those caveats, and am sorry."

It astonishes us how an 'expert' testifying under oath can draw such misleading conclusions from reports that have been widely criticized, are not transferable, and whose own authors insist are preliminary and inconclusive.

DEC 15 2008
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