A landmark agreement has been reached between a number of Government departments, including the Ministry of Defence, and industry which aims to remove aviation and radar barriers to the major expansion of wind energy.

Extensive MOD trials have proved that wind turbines can mimic, distort, mis-locate, duplicate or even temporarily conceal the smaller radar reflections from aircraft.

Representatives from the Department for Business, Enterprise and Regulatory Reform, the Ministry of Defence, the Department for Transport, the Civil Aviation Authority, NATS and the British Wind Energy Association signed a Memorandum of Understanding (MOU) on Friday 13 June 2008.

The signing reflects the Prime Minister's commitment to find a technical solution to aviation and radar objections to wind farms. One of the key National Security responsibilities of the MOD is to maintain the integrity of the UK's airspace. Complex airborne threats generate unprecedented challenges to Air Defence surveillance systems in order to maintain that integrity.

Furthermore the MOD, alongside the Civil Aviation Authority, is responsible for the provision of safe Air Traffic Control services to both military and civilian aircraft flying in some of the most congested airspace in the world.

Extensive MOD trials have produced clear evidence of wind turbine interference phenomena, with the most pressing concern being the significant interference caused to Air Defence and Air Traffic Control radar systems. The irregular energy patterns reflected from wind turbines can mimic, distort, mis-locate, duplicate or even temporarily conceal the smaller radar reflections from aircraft.

The growing number of windfarm developments increases the amount of clutter on radar screens. There is potential that this could create difficulty for Air Traffic Controllers within busy UK airspace to ensure safe separation between aircraft under their control and other unknown aircraft that could be hidden or obscured. Surveillance in support of the National Air Defence task is even more complex; operators looking for potentially hostile aircraft could be similarly hampered by the effects of windfarms on their radars.

The Ministry of Defence is committed to maintaining the safety and security of UK airspace, cooperating with industry on more trials and development work on radar and wind turbine technology in order to develop technical mitigations and increase our knowledge base.

Under Secretary of State for Defence Derek Twigg said: "This MOU reflects the proactive stance that the MOD is taking to progress and resolve the complexities behind wind farm projects, whilst ensuring that the nation's air safety and national security needs are not compromised. The agreement identifies future work streams that need to be undertaken in a collaborative manner across Government and Industry."