Building a 230ft (70m) wind turbine to supply energy to the Glyndebourne Opera House could spoil the tranquility of the South Downs, conservationists said today.

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

Officials at Glyndebourne - famous for its production of Mozart operas - say the turbine forms part of their 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 (CPRE), who are due to give evidence to the inquiry today, 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 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."

He said the urgent need to combat climate change should not be at the expense of landscapes which we are seeking to protect.

Mr Oliver added: "It is a sad irony that Glyndebourne, which is rightly renowned for creating one kind of beauty, should care little that their scheme could deprive so many people of another precious experience."

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

He said: "That such a celebrated institution should pay such regard to its environmental responsibilities seems to be wholly admirable, demonstrating as it does that some communities really do take the ecological challenge seriously and do not simply utter pious words and leave it to others to take action."

Sir David, 81, attacked the Nimby (Not In My Back Yard) attitude, a tag which those opposed to the turbine insist is not applicable to the way they feel.

He said: "It is difficult to predict the effect that climate change might have in the coming decades... But the larger picture cannot but be very alarming, with rising sea levels, increasingly severe storms and dislocation of ecological relationships on a major scale.

"These changes can only be minimised if people everywhere recognise their communal responsibilities."

David Murray, countryside campaigner for the Ramblers' Association, said findings by the CPRE highlighted an inappropriateness in both scale and location for the turbine.

And 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."

The proposal gained approval from councillors on Lewes District Council last year despite recommendations from their officers for the plan to be rejected amid concerns about its visual impact.

The inquiry inspector will report to the Government for a decision later in the year.

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