We know local residents will have questions about the proposed wind farm development. There are a number of principal issues that will be considered by Bord na Móna during its environmental impact assessment.
Bord na Móna will ensure that setback distances from residential dwellings will be in line with current guidelines and are cognisant of the 2017 draft preferred approach to the amendment of the existing Wind Energy Development Guidelines, This will ensure that the setback distance will therefore be sufficient to meet all noise criteria.
We will ensure that there are no shadow flicker impacts from Derryadd Wind Farm by using an engineering solution that has been successfully demonstrated at the Bord na Móna Mountlucas Wind Farm in Co. Offaly.
Recent international medical studies have indicated no adverse health effects on the general health of residents in the vicinity of wind farms.
Property prices and values are driven mainly by macroeconomic conditions. The impact of wind farms on property prices has been the subject of many peer reviewed studies internationally, none of which show any sustained negative impact on property prices.
In order to reduce the visual impact a number of mitigating measures will be used:
- Use of matt, non-reflective finishes.
- All connecting cables underground.
- Colour harmony and screening of substations.
The existing Wind Energy Development Guidelines published in 2006 do not have a prescribed setback distance but do indicate that a 500m setback distance should be sufficient to prevent any significant noise impact arising from the operations of wind turbines.
The draft preferred approach outlined in a recent press release propose a “visual amenity setback of 4 times the turbine height between a wind turbine and the nearest residential property, subject to a mandatory minimum distance of 500 metres”. The distance to the nearest house from a turbine will vary for each project depending on the various constraints applied to each design and the scale of the project. As turbine layout(s) are developed Bord na Móna will inform the local community through project specific information material of the setback distance for the project. However, it will never be less than 500m.
“Setback distance” is a term used to describe the distance between a residential property and the nearest turbine of a proposed development. The existing Wind Energy Development Guidelines (2006) do not have a prescribed setback distance. They instead rely on the noise limits outlined in the guidelines to determine the appropriate setback distance for each specific wind farm development.
The 2017 draft preferred approach propose a mandatory minimum distance of 500 metres between a wind turbine and the nearest residential property and four times the tip height, whichever is greater.
Wind turbines can generate two types of noise: mechanical noise from the generator in the nacelle (the cover which houses the generator, gearbox, drive train, and brake assembly), and aerodynamic noise from the blades. Turbine design has evolved to minimize both of these, through improved soundproofing of the nacelle and through streamlining and refinement of the turbine blades.
The Department of the Environment, Heritage and Local Government in 2006 published “Wind Farm Planning Guidelines” which set noise limits detectable at dwellings adjacent to wind energy developments. The guidelines state that “in general, noise is unlikely to be a significant problem where the distance from the nearest turbine to any noise sensitive property is more than 500 metres”. The limits set were 45 dB (A) or a maximum increase of 5 dB (A) above background noise during the day; and 43 dB (A) at night time. The 2017 preferred draft approach to wind energy development proposes “the application of a more stringent noise limit, consistent with World Health Organisation standards, in tandem with a new robust noise monitoring regime, to ensure compliance with noise standards”. It is expected that further detail on the specific noise limits will be forthcoming in late 2017 and early 2018. Noise levels are monitored at Irish wind farms, and if you have concerns, visit Mountlucas Wind Farm, stand 500m downwind and listen.
Shadow flicker is an effect that only occurs at certain times of the year and under certain conditions. The rotating wind turbine blades may cast shadows over the windows of houses that are closest to the turbines. Generally residences further than 2km away from a turbine are not affected by this. The effect lasts only for a short period and happens only in certain specific combined circumstances such as when:
The sun is shining and is at a low angle (i.e. very early in the morning after sunrise or late in the evening before sunset) during the winter months; The turbine is located directly between the sun and the affected property; Wind direction (position of turbine blades): the turbine blades are facing directly toward or away from the sun; There is enough wind energy to ensure that the turbine blades are continually rotating.
Any obstacles such as trees or buildings located between a property and the wind turbine will reduce or eliminate the occurrence and/or intensity of the shadow flicker.
Modern wind turbines can be fitted with shadow flicker control units that allow a wind farm’s SCADA control system to turn the turbine off if necessary when shadow flicker is likely to be an issue at properties surrounding the wind farm. The strength of direct sunlight is measured by way of photo cells, and if the sunlight is of sufficient strength to cast a shadow, the shadow flicker control mechanisms come into effect. Wind speed and direction are measured by anemometers and wind vanes on each turbine and on the wind farm’s met mast, and if wind speed and direction is such that a shadow will be cast, the shadow flicker control mechanisms come into effect. Bord na Móna’s Mountlucas Wind Farm uses the turbine control software to automatically shut down a turbine during periods of likely occurrence of shadow flicker.
No. Modern wind farms started to appear just over 30 years ago. Since then 314,000 have been built in the world and “there is no reliable or consistent evidence that wind farms directly cause adverse health effects in humans” (As advised to the Irish Government in April 2014 by the Irish Deputy Chief Medical Officer). Recent international medical studies have indicated no adverse health effects on the general health of residents in the vicinity of wind farms.
Property prices and values are driven mainly by supply and demand and by macro-economic conditions. The impact of wind farms on property prices has been the subject of many peer reviewed studies internationally, none of which show any sustained negative impact on property prices.