Trade and industry secretary Patricia Hewitt has announced a huge expansion of offshore wind farms.

Hewitt has revealed plans for firms to build enough wind generators to provide energy for up to one in six of Britain's homes.

The projects will focus on three UK coastal regions of Thames Estuary, Greater Wash and the North West and could involve investment of up to £6 billion.

Ministers also believe that the project could create an estimated 30,000 jobs.

With North Sea oil running out and Britain's older nuclear power stations nearing closure dates, ministers have been searching for new ways of providing the country's growing energy needs.

Hewitt said there was strong public support for renewable energy based on a new opinion poll that showed 74 per cent of bill payers supported the increased used of wind power.

"This announcement is good for the environment, good for Britain's energy needs and good for jobs," Hewitt said.

"Offshore wind has potential to provide a significant proportion of the UK's energy needs.

"It will help the UK renewables industry to grow, building on our world leading expertise in offshore manufacturing, creating over 20,000 new jobs in manufacturing, installation and maintenance, as the windfarms take shape."

News of the announcement received a broad welcome with the caution that it is a long-term initiative.

Vince Cable, the Liberal Democrat DTI spokesman, said the government should see the intiative as a first step towards diversifying into alternative energy sources such as wave and solar power.

"The is a significant sign that the government is getting behind renewable energy in a big way by taking wind power above the threshold of commercial viability," he said.

"If Britain is to meet its targets for renewable energy we should not put all our eggs in one basket by backing one technology above all others."

Experts cautioned against the idea that the initiative would be a replacement for nuclear fuels.

"We must not lose sight of the fact that the wind only blows a third of the time and cannot ever be expected to supply the major proportion of the nation's energy requirements," said Tom Foulkes of the Institute of Civil Engineers.

Environmental campaigners at the Royal Society for the Protection of Birds, said it was vital environmental concerns stayed high on the government's agenda.

"In principle we support the use of offshore wind to power our homes and industry and reduce the dangers of climate change. And by locating wind farms away from important areas, they will help reduce greenhouse gas emissions and minimise the risk to birds posed by climate change," said spokesman Mark Avery.