In a leaflet distributed at a local meeting, West Coast Energy said there was no evidence wind turbines reduced nearby property values and they could even have a positive impact.
However, following a complaint, the ASA ruled the company must stop using the leaflet and not repeat the claims without more robust evidence.
West Coast Energy took its claims from a 2007 research paper by the Royal Institute of Chartered Surveyors (RICS) and a 6-year study from the USA.
The ASA said that the RICS research was out of date, “largely speculative” in its findings and showed a negative impact on house prices in some cases. As for the US study, it said there was not enough evidence the findings applied to the UK.