Scotland could generate enough "green" energy to meet its own needs and supply other parts of the UK, a new report has said.

Scotland has the largest potential supply of wind-generated energy in Europe, and adding to this the possibility of producing wave and tidal stream energy could generate up to 60 gigawatts of electricity, a figure equivalent to three quarters of Britain's current capacity.

The energy could be generated on a cheaper basis than nuclear, oil or coal power, says a report for the Scottish executive.

Playing down fears that large numbers of wind farms could detract from scenic areas, the report also said that Scotland's peak winter energy demand could easily be met without building in designated areas of natural beauty.

Ross Finnie, the Scottish environment minister, described Scotland's green energy potential as "breathtaking".

"This hugely significant study outlines the breathtaking scale of Scotland's renewable energy potential and vindicates our strongly-held belief that we are ideally placed to benefit from the sustainable energy revolution," he said.

Another report said there was enough capacity in the national grid to transport the green energy, but the infrastructure was not yet in place to connect new wind farms to the grid.

"But both reports demonstrate that Scotland, both in environmental terms and in economic terms, stands to gain hugely from this potential energy resource," said Finnie.

Meanwhile in Wales, ministers said they were leading the UK in supporting wind power.

Assembly environment minister Sue Essex has said that Wales contains over 40 per cent of UK wind turbine capacity. And there will be a review of planning guidance to make future wind farm developments easier, she said at the opening of the Parc Cynog Windfarm, Carmarthenshire.

"The assembly government wants to see a renewable energy industry which will flourish in Wales. There is great interest and potential," she said.

The focus on green energy comes as ministers at Westminster prepare to publish their review of Britain's future energy needs.

Number 10's Performance and Innovation Unit is reported to have rejected calls for an expansion of nuclear power and will instead concentrate on meeting future energy requirements from green sources, ensuring Britain still meets its Kyoto targets on cutting greenhouse gases.