The government must allow wind farms to be built closer to the shore if project developers are to build a robust business case for investors, according to a new study from The Carbon Trust.

Under proposals, the next generation of offshore wind farms proposed by the government will have to be built in deep water a minimum of 70 miles from the shore.

However, while the policy is expected to ensure that the developments face minimal opposition from local residents concerned about the visual impact project, it is expected to add significantly to construction costs.

According to the Carbon Trust study, allowing more wind farms to be built nearer the shore would cut costs by £16bn while also allowing developers to complete projects in shorter time frames.

Relaxing planning rules for near shore sites would be key in helping the UK to meet its 2020 renewable energy targets, said Tom Delay chief executive of The Carbon Trust.

"The government must use the upcoming consultation on this important issue to unlock the most economically attractive sites for development," he said. "This would dramatically reduce the cost of development – essential if we are going to meet our 2020 renewable targets and deliver significant reductions in our carbon emissions."

Other recommendations in the report, Offshore wind: big challenge, big opportunity, include removing grid and planning regulatory barriers, increasing public R&D funding and modifying the current incentive mechanism.

The report argues that, if adopted, the recommendations could cut the cost of developing offshore wind by up to 40 per cent, slashing £30bn from the total bill.

"We've laid out a series of measures to ensure the offshore wind industry delivers at scale over the next 12 years," said Delay. "With the right innovation and manufacturing strategy, the UK could see up to 70,000 jobs created and up to £8bn in revenues generated every year.”

Duncan Ayling, head of offshore at the British Wind Energy Association, said the report makes a clear case for getting the regulatory framework governing offshore wind development right.

"The outcome could be a revolution in the way electricity is produced and distributed in this country, with potentially 25 per cent of UK electricity demand being powered by offshore wind," he said.

The report was also welcomed by John Sauven, executive director of Greenpeace, who argued that offshore wind energy should form a vital component of a low carbon economy.

"We need to promote a massive redirection of investment away from the speculation that has caused the bursting financial and housing bubbles and into new green industries and job-creating programmes that will help us tackle climate change," he said.

The Crown Estate, which is responsible for the areas on which the next generation of offshore wind farms are to be built, recently issued an invitation to registered developers to bid for the rights to develop up to 25GW of new offshore windfarm sites by 2020.

Rob Hastings, director of the Marine Estate for The Crown Estate said it supported the recommendations of the report.

"We support the report's dual priorities to reduce project costs and to align the UK's planning and grid regulatory regimes with the country's renewable energy targets for 2020," he said. "We are confident that opportunities to find solutions to these challenges and to deliver the potential of offshore wind are presented by the Round 3 programme."

The government will now consider the recommendations of the report, according to Energy and Climate Change Minister Mike O'Brien. "The issues of fairness and cost-effectiveness, along with effects on the environment and on other users of the sea will be considered carefully in the lead up to our renewable energy strategy to be published next spring," he said.