The proposed wind farm will consist of ten wind turbines (with a power generation potential of 2.3MW each), appropriately spaced over the site, as well as the associated infrastructure for connection onto the existing power grid, and access for maintenance purposes, as required for the particular site selected. Each turbine will have a tower height of 80 meters, and a rotor diameter of 85 meters (total height is therefore 122.5 meters). Phase 1 of the proposed development will have a total power generation potential of 20MW, with possible future expansion to 40MW (by the addition of more turbines), depending on the area limitations of the site.
The three site alternatives (Figure 5) have been selected for their suitability with regard to wind, topography and conservation status, and will be examined in more detail in this report.
The proposed development falls within three quarter degree squares, namely 3325CC, 3325CD and 3325DC and the number of bird species recorded in these squares by the South African Bird Atlas Project (SABAP) range from 272 to 325 species. Of these species 36 are Red List species, with two classified as Endangered, 10 classified as Vulnerable and 24 classified as Near-threatened. One bird species is protected internationally under the Bonn Convention.
The proposed development can be built with acceptable impact on avifauna should the recommendations regarding site selection in this report be followed.
The Bushy Park site is the most preferred site alternative from an avifaunal perspective and the Driftsands site is least preferred. The Driftsands site should be discarded as an alternative from an avifaunal perspective.
With regards to bats, the Van Staden site is the most preferred site alternative with Bushy Park and Driftsands being least preferred.
In particular the following important points must be stressed:
- A Site specific EMP is strongly recommended to site the turbines correctly as well as to deal with the details of the associated infrastructure that was not provided at this stage of the process.
- A monitoring program is seen as critical in extending our knowledge of wind energy and avifaunal and bat interactions. Since this could be the first commercial wind energy facility in South Africa, it is recommended that a monitoring program be planned to collect data on a host of environmental factors, including avifaunal collisions and bat fatalities.
- Turbines must be painted as detailed in this report to mitigate for collision of bird species.
- If possible the wind turbines must be shut down in extreme wind and extreme low visibility events such as thick cloud or mist.
- If possible the wind turbines should be shut down in low-wind conditions at night when the bats are foraging.
- The wind energy facility should not be lit, if this is not feasible the lights must only be red strobe lights and lights that do not attract insects.
- The use of a radar to alert bats to the presence of wind turbines is strongly encouraged.
It must also be stressed that with wind energy and avifaunal interactions the cumulative impacts of multiple developments could be important. It is recommended that a national or at least municipal strategic study be undertaken to address this issue.