A report which has been commissioned by the government is expected to be approved this week and allow plans for the Swansea Bay tidal lagoon to go ahead. This will allow the pioneering project to unlock a series of other tidal electricity projects which are worth several billion pounds together.

Last year, ministers commissioned the review to see if wave and tidal energy could provide affordable clean energy to Britain. At the time, it was widely believed to be a means of killing off the ambitious tidal lagoon plans.

However, sources now believe that the conclusion will be 'broadly positive' and recommend progression of the £1.3 billion prototype build.

The Swansea project is viewed as being the pathfinder project before five other sizeable areas, in Colwyn Bay, Newport, Cardiff, Somerset and the Cumbrian Coast, develop their own wave and tidal power projects. If successful, these sites could generate up to 10pc of Britain's total electricity requirements and help to slash greenhouse gas emissions in the process.

£35 million has already been spent by Tidal Lagoon Power on the Swansea project. The development would involve installing a revolutionary new U-shaped breakwater across the waters of the bay so that the tide passes through a series of turbines, producing enough green energy to supply the electricity needs of 150,000 homes.

A guaranteed sale price for the power is yet to be agreed between the government and developer. The negotiations on this price are continuing, and David Cameron, the former prime minister, had said he had concerns over high costs.

The key to success will be for the project to demonstrate that the technology can be cost-competitive without the need for a subsidy to support it, especially as other renewables have already been forced to demonstrate market competitiveness.