A 230ft wind turbine to supply energy to Glyndebourne could spoil the tranquillity of the South Downs, say conservationists.

Plans for the 850kw turbine on Mill Plain, between Ringmer and Glyndebourne, are being discussed at a public inquiry in Lewes.

The opera house says it forms part of its vision to cut carbon emissions by 71 per cent and make the venue more environmentally sustainable. But campaigners, including representatives from the Campaign to Protect Rural England who are due to give evidence to the inquiry, insist such an addition could harm the protected landscape.

Tom Oliver, the CPRE's head of rural policy, said: "This huge turbine would be clearly visible from a great tract of the countryside, including from the South Downs Way national trail.

"Its rotating, spiky blades would disrupt the magnificence of the broad horizon of the Downs and distract anyone seeking to find inspiration from the harmonious landscape of this special part of England.

"There is a growing consensus that the experience of tranquillity is beneficial to human health and well-being. Increasingly, this experience is threatened and diminished by poorly conceived and located development."

The proposal has gained support from unexpected quarters, including veteran wildlife broadcaster Sir David Attenborough, who told the inquiry he "greatly applauded"

it.

Jacquetta Fewster, director of the South Downs Society, said: "People come to the South Downs to get away from the rush and noise of modern life.

"They want to take in unspoilt views and listen to the wind in the grass. The challenge is to build renewable energy technology which doesn't destroy the tranquillity and beauty we all cherish so much."