North Hoyle Windfarm Report

6 MCA Radar trials

6.11 Sea and rain clutter within the wind farm

High winds and swell will produce sea clutter within the wind farm which will itself interfere with the detection of targets. The presence of WTGs against which waves might break may increase the overall sea clutter, which can be reduced by the swept gain control on basic radar equipment. Again, however, the reduction of gain may reduce detection and tracking abilities.

Tripod foundations may produce greater sea clutter than monopiles.

Rain clutter is produced by reflection from water droplets and, again in simple radar systems, its effect is reduced by employing fast time constants (FTC). There is generally a noticeable reduction in detection abilities when FTC is employed. An example of a radar display showing rain clutter near to the wind farm is shown in Figure 6-19.

At all times when the trials were being undertaken, there were light winds, calm seas and clear visibility. This had some advantages in that the vessels involved were able to look at effects close to turbines. However, because of these conditions, the effects of sea clutter and precipitation in combination with the wind farm’s own interference effects were not able to be examined.

Benchmarks for the range of first detection in clutter conditions are to be included in the MCA project mentioned above, clutter environments for both sea state and rainfall and as combinations of these being defined.

Figure 6-19: Precipitation effects