Many people concerned with wind turbines have a specific fear: that the equity in their properties will be reduced or eliminated. How real is this? What is the actual impact of wind farms on nearby property values?
Six major and statistically reliable studies covering almost 100,000 property transactions by different respected and independent organizations in different countries spread over fifteen years have found no correlation between operating wind turbines and negative property values (in fact, two found positive impacts).
- The prestigious US-based Lawrence Berkeley National Laboratory found no correlation in 2009 and 2013 studies.
- The respected UK-based Royal Institute of Chartered Surveyors in combination with the Oxford Brookes University found no correlation.
- The US-based Renewable Energy Policy Project found positive correlations between wind turbines and property value increases.
- A University of Illinois Masters in Applied Economics thesis found statistical evidence that fear of an impending wind farm affects property values, but that operating wind farms do not, and that property values near operating wind farms increase faster.
- A recent New Hampshire study found no correlation between wind farms and property values.
- Fear of wind turbines impact on property values before the wind turbines are erected and shortly afterward seems to have a short-term impact on property values and sales. If so, anti-wind advocacy groups are complicit in this – arguably intentionally — by publicizing and promoting fear of property value impacts.
Note: The LBNL just released an updated study covering a separate 50,000 transactions and found no evidence of property value loss. This blog post will be updated more completely with an analysis of the findings.
Respect the concern
To ensure that the seriousness of this organization and its devotion to academic excellence and scientific truth is understood, thirteen Nobel Prize winners have been associated with the Lab and thirteen have been awarded the US National Medal of Science, the top US honor for lifetime achievements in science. Dozens more have received other extraordinary levels of recognition. This is an organization that is not for sale. This is an organization that takes its independence and excellence seriously.Here’s what they found:
The present research collected data on almost 7,500 sales of single- family homes situated within 10 miles of 24 existing wind facilities in nine different U.S. states. The conclusions of the study are drawn from eight different hedonic pricing models, as well as both repeat sales and sales volume models. The various analyses are strongly consistent in that none of the models uncovers conclusive evidence of the existence of any widespread property value impacts that might be present in communities surrounding wind energy facilities.
It is worth noting and debunking the arguments used against the study:
- It doesn’t agree with what is obviously happening around the person observing; statistics have never had much success in convincing someone who believes something and receives sufficient evidence to support their confirmation bias.
- The Lab is government-funded; the bona fides and independence of the LBNL are top-notch and questioning them indicates the rhetorical or intellectual disposition of the questioner.
- The study excluded 34 statistical outliers; statistical studies of any size do this to eliminate unrepresentative data and 34 exclusions on a sample size of 7,500 is miniscule. This study is accurate and has not been gamed.
The next study is the 2007 study by the Royal Institute of Chartered Surveyors (RICS)  in conjunction with Oxfords Brookes University , .
These are serious, respectable and trusted institutes as well; RICS traces its history to chartering in 1792 and is a pre-eminent standards setting body world-wide. The researchers assessed property transactions within five miles (8 kilometers) of three wind farms from 2000 to 2007. This provides geographical, distance and time-frame perspectives. They eliminated transactions where significant other factors would impact prices: a large open cast slate mine, very expensive properties, very cheap properties and sea view properties. This was to provide a clear view of specifically wind turbines’ impact on property values. This left them with 919 transactions, which is statistically valid.
Despite initial evidence that there was an effect, when they investigated more closely, there were generally other factors which were more significant than the presence of a wind farm. Insofar as there was any impact on prices, the results seem to show that it is most noticeable for terraced and semi-detached houses, with there being a significant impact on properties located within a mile of a wind farm. The effect seems much less marked – if at all – for detached houses.
Regarding the terraced and semi-detached houses:
The view of the estate agents was that proximity to a wind farm simply was not an issue. What they did say, though, was that the properties close to one of the wind farms – St Eval – were, in fact, ex-Ministry of Defence properties, and so less desirable than similar properties.
To paraphrase, while people blamed wind turbines for property value decreases, other factors were much more significant, and detached homes, the dominant form of real estate near wind farms showed no price impacts.
Unfortunately, RICS has removed this survey from their available publications on their website and appear to not be standing by the results of their research.
The third major study worth assessing is the Renewable Energy Policy Project’s (REPP) 2003 study.
While the oldest, it also assessed the largest pool of data, more than 25,000 property transactions in the USA. They looked at every home within 5 miles (8 kilometers) of ten large (>10 MW) wind developments that came online between 1998 and 2001. They gathered sales data for the control regions near the wind turbines but outside of the 5 mile (8 kilometer) boundary to ensure that they could assess differences accurately. They gathered six years worth of data covering the years leading up to and following the wind farms’ online dates. 
It is worth noting that while this is by far the largest study with the least statistical adjustment of data, the creator of the study, REPP, is an organization whose public and stated goal is to accelerate the use of renewable energy.  As such, while the study design is arguably very good and sample size the largest, it is the easiest to discount due to the source.
What did they find:
- For 8 of the 10 of the wind projects, property values increased faster inside the five mile limit than outside of it over the six years.
- For 9 of the 10 wind projects, property values increased faster within the five mile limit after the wind projects came online than they had before.
- For 9 of the 10 wind projects, property values increased faster within the five mile limit after the wind projects came online than in the comparable communities.
Not only did this massive study not find negative impacts on real estate values, it found exactly the opposite: wind turbines have a positive impact on real estate values.
A fourth study is also worthy of inclusion: “Wind Farm Proximity And Property Values: A Pooled Hedonic Regression Analysis Of Property Values In Central Illinois” by Jennifer L. Hinman in partial fulfilment of a Master in Applied Economics with Illinois State University in 2010. Her study evaluated 3,851 residential property transactions from January 1, 2001 through December 1, 2009 from McLean and Ford Counties, Illinois around the 240-turbine, Twin Groves wind farm (Phases I and II) in eastern McLean County, Illinois.
Ms. Hinman’s study found no correlation between a working wind farm and decreased property values, in fact saw more rapid price increases nearer to the wind farm as was observed in the REPP report. Her study most clearly shows that there is a statistical correlation between fears about a wind farm before it is erected, temporarily depressing property values, and that this temporary dip is rapidly eliminated once the wind farm is in operation.
Ms. Hinman also did a literature review and found the same results: all major statistically valid studies find no negative correlation, but very small studies at or just above the level of the anecdotal do find negative impacts.
A New Hampshire, USA study published in December 2012 assessed another 4,600 property transactions and found:
While this study does not exclude the possibility of isolated cases of property value impacts attributable to the Lempster Wind Power Project, this study has found no evidence that the Project has had a consistent, statistically‐significant impact on property values within the Lempster region. This is consistent with the near unanimous findings of other studies—based their analysis on arms‐length property sales transactions—that have found no conclusive evidence of wide spread, statistically significant changes in property values resulting from wind power projects.
Two correlation graphs from this study paint a clear picture.
Note that distances are in kilometres.
Basically, there’s no variance on home prices due to distance from wind turbines, and a huge correlation to size of dwellings.
A preliminary Australian study indicates that this is also true south of the equator. While the sample size of sales transactions is low, they found that 40 of 45 sales transactions had no evident reduction in value in close proximity to wind farms and that properties that were in sight of wind farms found no reduction in value. 
They also did a literature survey and summarized additional references with similarly devastating results for studies showing negative impacts:
What is the evidence that shows negative impacts?
There is one statistically valid, methodologically sound, peer-reviewed study which contradicts the preponderance of evidence above. Martin Heintzelman and Carrie Tuttle did a study of 11,331 property transactions over 9 years in three counties in Northern New York, 461 of which were within three miles of wind turbines. They found that two of the three counties had significant property value decreases while the third had positive indicators. For context, this study is relatively equivalent in terms of organizational respect and depth to Ms. Hinman’s study from Illinois State University; credible but not from a world-class organization such as the Berkeley Lab or RICS.
A significant failing of the study that makes it difficult to trust compared to other studies is the short time frame of the data for the two counties with negative impacts. Their wind farms became operational in 2008 and 2009, basically in the last year of the data set. The county with positive impacts went live in 2006, in the middle of the data set, providing a much richer analysis space. There are several other significant differences between the two counties that showed negative results and the county with positive results as well.
- The two counties with negative impacts (Franklin and Clinton) had significantly fewer transactions — 210 between them — than the county with some positive impacts (Lewis) which had 251 transactions.
- The two counties with negative impacts had significantly higher resales of properties than the county with positive impacts, 75 to 65.
- The two counties with negative impacts are adjoining to one another with the third county two hours drive away, effectively in another community conversation region and making it possible for other local impacts to be masked; three completely separate or three completely co-located regions would have eliminated this oddity.
- The two counties with negative impacts had fewer wind turbines on average than the county with positive impacts (221 between them to 194 in Lewis).
This region also has a robust set of anti-wind activist groups. The 2011 anti-wind documentary, Windfall , is from upstate New York, and Lisa Linowes, a long term anti-wind advocate with ties to astroturf-supporters such as the Heartland Institute and the Koch brothers  was the sole technical advisor to the movie and has been active in the area.
Despite the largest county with the longest history of wind energy and the most transactions having positive indicators for property values, the authors focused their conclusions dominantly on the negative counties. The authors state in their preamble that they did not believe it possible that wind turbines didn’t negatively affect property values. They found the results they expected, ignoring the significant oddities in their results.
The examples listed in the question and others ,  represent real people telling the truth as they see it, which is to say, from a limited perspective in both space and time. What they are observing is accurate but restricted.
- Some people do not buy homes when they understand that wind turbines might be going up near by
- Some people do sell or try to sell their homes when they hear that wind turbines are going up
- Property prices do dip under those conditions: this is a real occurrence, supported by the Illinois statistical study.
What are the fears that are driving this?
- Fear of health is one, with the psychogenic Wind Turbine Syndrome and it’s equally fictitious cousin Vibro-Acoustic Disease. Note that these are not real diseases, but they are promoted by both the originators of the concept and by anti-wind advocacy groups as being real, and they are creating a health hysteria in English-language countries around wind energy., , 
- Fear of property value decreases, which this article is assessing.
- Fear of wind turbines collapsing, throwing blade parts or causing fires. These are so massively unlikely that no rational analysis would include them, but they are highly evocative. 
These are real fears of unreal things. They are strongly promoted by anti-wind advocacy groups. It is strongly arguable that anti-wind advocates drive down property prices in the run up to wind farms becoming operational just as they are creating the psychogenic health hysteria, “Wind Turbine Syndrome.:”
 The Impact of Wind Power Projects on Residential Property Values in the United States: A Multi-Site Hedonic Analysis
 “Wind turbine syndrome” is more wind than syndrome
 Wind farms don’t make people sick, so why the complaints?
 Humans evolved with infrasound; is there any truth to health concerns about it?
 Wind farms causing fires? All smoke, no flame