The amount of noise two proposed 100-metre wind turbines would generate has been understated by developers, a planning inspector was told.
A fourth public inquiry into plans to build the structures in Church Lane, Shipdham, got under way today.
Ecotricity has had its proposals refused four times by Breckland Council over nearly 12 years.
The energy firm, which has seen its previous appeals taken to public inquiries and the High Court, appealed once again after its latest planning application was turned down in August 2012.
The planning inspector John Watson ruled in March that it would have to be taken to an inquiry – and this time the decision will be made by the Secretary of State, Eric Pickles.
Opening the inquiry, which is expected to last six days, Mr Watson said the key issues were to determine the extent to which the proposed development conforms to the development plan and the national planning policy framework, and whether any permission should be subject to conditions.
Under the plans, the two wind turbines would be built at Wood Farm.
Giving evidence on behalf of the residents of nearby Daffy Green, Lee Hoare explained to the inquiry how, according to her research, the closer the turbines are together, the greater the noise they will generate.
Dr Hoare said: “Noise impacts have been understated in this application.
“Predicted noise levels understate real noise levels once the wind turbines are built, despite the government being told that the predictions are robust.”
The Shipdham wind turbine dispute has rumbled on since Ecotricity, which runs the Swaffham turbines, lodged their first application in 2002. It has split the local community with groups in favour and against set up.
On previous occasions, the plans were twice turned down on noise grounds and once quashed on noise conditions.
John Campbell QC, representing opposition group Campaign Against Turbines in Shipdham, said: “Several hundred people will have to suffer significant visual impact.”
During his opening speech, Jeremy Pike, representing Ecotricity, said: “The local landscape isn’t any more significant than any other areas where wind turbines have been approved and built.
“None of the properties will have an open view of the wind turbines and the turbines will not change the landscape so much to make it an unattractive place to live.
“Not only are schemes like this needed to reduce carbon emissions and to secure the electricity supply but also, the impact of these proposed turbines is something which can and should be considered as acceptable.”
The inquiry continues.