AN independent body advising the Government on climate change has criticised the controversial Severn Barrage plan as "not clearly attractive".

The independent Committee on Climate Change said onshore and offshore wind farms, nuclear power stations and carbon capture technology were more viable alternatives than harnessing power the Severn estuary tides.

Plans for the Severn were "relatively expensive" compared to other low-carbon options currently available, although it may become an attractive option in the future if "other technologies fail to deliver".

The committee's report came as energy minister Lord Hunt told MPs that a decision on the Severn could be delayed.

The Department for Energy and Climate Change is expected to decide next year whether it will press ahead with any of the proposed plans, which could generate as much as 5 per cent of the UK's energy needs.

Lord Hunt admitted to an Energy Select Committee that one option being considered was to wait for fledgling technology to develop.

Meanwhile, officials admitted building the controversial Severn Barrage would cost far more than the £21 billion price tag currently put on the controversial scheme.

Connecting the 10-mile-long energy- generating development between Cardiff and Weston-super- Mare, Somerset, to the National Grid would alone add an extra £2 billion to the cost.

In its report, the Committee on Climate Change said generating electricity by way of a Severn Barrage would be "more costly than the leading low-carbon alternatives".

It added: "Investing in a barrage is therefore not clearly attractive if these alternatives are available.

However, we note that nuclear, carbon capture and other renewables carry their own delivery risks, and the option of constructing a barrage at the Severn in future should therefore be kept open.

"As such, even if building a smaller barrage or lagoon proves more cost-effective, it may not be desirable to proceed with this option if it rules out the addition of a large barrage in the future."

In the report to Parliament, entitled Meeting Carbon Budgets, the committee highlighted wind power as offering the "best opportunity" low-carbon energy, adding that it was the "only low-carbon technology that is ready for deployment now".

But if planning decisions remained at the current sluggish speed – two years to approve a large onshore wind project – only a fraction of new wind capacity could be added by 2020.

There were jeers when controversial plans to build 20 wind turbines in Davidstow, near Camelford, were approved by Cornwall Council's strategic planning committee this week.