Site Selection

Wind is abundant, but intermittent. It varies day to day and season to season, and can differ by as much as 20% year by year. To harvest the best available wind, site location is critical. The following key factors are important considerations:

• Higher elevations produce better wind speeds and lower turbulence, and therefore higher annual power capacity. We recommend that your turbine is at least 10m above any obstacles within 100m. This may require additional permit consideration, but it’s well worth the effort.
• Turbulence reduces the effectiveness of blades, so avoid sites which are near woodland, buildings or sheer cliffs.
• Find a South West location, as this is the source of 80% of the UK’s prevailing wind.
• Air density and therefore wind turbine performance decrease with altitude. In the UK, this effect is however negligible (10% per 1,000m).
• Locate at least 10 rotor diameters from other residential dwellings.
• To minimise any noise disturbance, locate with the turbine to the NE side of your property.
• If you’re using more than one turbine, make sure that each one gets clean, turbulence free wind. As a rule of thumb, there should be a minimum of 5 x rotor diameter distance between turbines perpendicular to the prevailing wind direction, and 10 x rotor diameter between turbines in the prevailing wind direction.
• Larger turbines need a 3-phase electricity supply in order to sell power back into the Grid – ideally 11kv, not a 33kv line.
• The longer the distance from the turbine to the consumer unit or grid connection point, the longer and more expensive the cable will be. Typically distances are 100m – 150m, but distances of more than 300m will become more expensive.
• Access to the site will be needed for a lorry or crane in order to deliver and install the turbine and tower.
• Choose the right tower. Putting a wind turbine on a tower that is too short is like mounting a solar panel in the shade.