A conservation charity has attacked the decision to approve Scotland's third largest windfarm in the Shetland Islands, warning it could herald "industrialisation on a massive scale."

The windfarm will consist of 103 turbines and will be run by Viking Energy, a partnership between Shetland Islands Council and power giant Scottish and Southern Energy (SSE).

The development has been controversial in Shetland and has met with bitter local opposition, with 300 people marching in capital Lewick in protest at the plans. 

Supporters of the scheme argue it will raise money and help meet renewable energy targets, while the developers have claimed it could be the world's most productive windfarm.

Responding to the Scottish Government's decision to authorise the scheme on April 4, chief executive of the John Muir Trust Stuart Brooks said: “This is quite possibility the largest industrial development in the history of Shetland. The scale of impact on the world renowned natural landscape of these islands is unimaginable.

“I’m extremely disappointed that the application has been approved by the Scottish Government. We felt a Public Inquiry was necessary to fully examine the application given the scale of local and national opposition.

“Our objection also included major concerns over the impacts on peatland and wildlife and there’s little indication that these have been adequately addressed. Restoration of peatlands is a highly cost effective means of mitigating global warming – it makes little sense to be digging them up to build wind farms.

“In addition to the environmental impacts, it was clear from the outset that this development did not have the full support of the local community. It has received more than twice as many objections as letters in support, despite a well-funded PR campaign to convince Shetlanders of its merits.

 “This decision sends a very clear signal that any wild landscape is vulnerable to industrialisation on a massive scale without statutory protection. I genuinely fear for the future of one of Scotland’s and the UKs most important economic assets if the Scottish Government continues on this path.”

The RSPB were also critical of the decision, expressing concern the scheme will damage breeding sites for rare birds such as red-throated divers and whimbrel.

Supporters of the scheme argue it will raise money for the islands, create jobs and help meet renewable energy targets.

The moors of Shetland's main island, where the windfarm will be built, experience the highest wind speeds in Europe.

The developers claim it could be the world's most productive windfarm, with a capacity of 370MW. They say it could power more than 175,000 homes (despite Shetland having a population of about 22,000) and bring about £30 million in annual income for the local community.

Bill Manson, chairman of Viking Energy Partnership, said: "An enormous amount of effort and extensive consultation resulted in us creating a project which is comprehensive, thorough and designed with Shetland's unique environment in mind.

"This is good news for Shetland, good news for Scotland and good news for the fight against climate change."

The project received 2,772 objections, more than 10% of Shetland's 22,000 total population. It was supported by 1,115 people.

The developers had initially proposed to build a 150 turbine windfarm, but scaled back its plans from 150 to 127 last September. The Scottish Government withheld permission for a further 24 turbines.