Draft PPS18: Renewable Energy
Annex 1 Wind Energy Planning Issues: Radar
A101. Any large structure is liable to show up on radar, but wind turbines can present a particular problem as they can be interpreted by radar as a moving object, which is only intermittently seen (as the nacelle rotates to face the wind). There is a consultation zone and an advisory zone around every civilian and military air traffic radar but objections may sometimes be raised in respect of developments further afield. Consultation by the developer will also be required in respect of any meteorological radar. Developers therefore need to carefully consider this matter and the British Wind Energy Association web site gives details of how adequate consultation can be achieved. In addition, developers may be required to contact the Irish Aviation Authority at the pre-planning stage with details of locations and proposed heights of turbines, to ensure that the proposed development will not cause difficulties with air navigation safety in the Republic of Ireland.
A102. Because topography, intervening buildings and even tree cover can mitigate the effect of wind turbines on radar, it does not necessarily follow that the presence of a wind turbine in a safeguarding zone will have a negative effect. However, if an objection is raised by either a civil aviation or Defence Estates consultee, the onus is on the applicant to prove that the proposal will have no adverse effect on aviation interests.
A103. The CAA has published a Civil Aviation Publication, CAP 764 CAA Policy and Guidelines on Wind Turbines (July 2006) to provide assistance to aviation stakeholders when addressing wind energy related issues. This seeks to ensure greater consistency across the whole aviation industry in the consideration of the potential impact of proposed wind turbine developments.