Energy consultancy TNEI Services has tackled the issue of wind shear head-on by developing their own method of modelling and assessing turbine noise which takes account of wind shear at individual wind farm sites. The method is founded on bespoke software designed in-house by TNEI’s noise experts in conjunction with colleagues in the Wind Resource Assessment team.
Recent research has shown Wind Shear to be an important consideration for wind farm planning and noise assessments because failure to consider wind shear can, on certain sites, lead to under prediction of levels of wind turbine noise.
The team is confident that its new method will improve the accuracy of wind turbine noise assessment providing developers, local planning authorities and wind farm neighbours with confidence that wind turbine noise has been comprehensively considered.
Wind shear is the relationship between wind speed at different heights above the ground, and in particular between the ground and hub-height of a wind turbine. This can vary depending on surrounding terrain, time of day and season.When assessing the noise emissions from a turbine, the noise team calculate wind shear using on-site measured wind mast data.
TNEI’s new modelling capabilities provide developers with a more accurate and robust picture of wind shear and potential noise on sites, allowing them to design and build wind farms that maximise potential power without compromising the amenity of wind farm neighbours.
TNEI’s wind shear model incorporates recent industry guidance and adds significant value by using detailed site-specific large wind mast data, already used to predict annual energy production for wind farm financing. The influence of topographic, diurnal and seasonal effects on wind shear are also fully considered.
In the past, TNEI has adopted a cautious approach to the issue of wind shear when performing its calculations. With the benefit of the in-house developed wind shear analysis software, the team has validated its previous assumptions and is offering clients a more accurate prediction of what noise will be emitted from turbines chosen for a particular site.
TNEI’s noise experts have worked closely with members of the wind resource team to develop the new software models. By combining the expertise of the two teams, TNEI has taken a multi-disciplinary approach to the issue of wind shear and produced software that offers comprehensive modelling assessments and solutions.
Notes on wind shear
Noise from wind turbines and how to calculate wind shear are key issues for developers and planners when considering wind energy projects.
Renewed debate has been sparked by the release of expert guidance on how to conduct noise and wind shear assessments on wind energy projects.
Leading noise specialists recently issued guidance via the Institute of Acoustics which outlined the guidance and assessment calculations recommended, to supplement existing ETSU-97 noise legislation.
TNEI’s Planning and Environmental Group employs a team of 6 noise specialists who worked closely with the company’s Wind Resource Assessment Team to create the new modelling software.