Developers plan private tidal power project for UK's Severn

LONDON (Reuters) - A group of developers is attempting to revive plans to harness tidal energy from Severn estuary between England and Wales to produce 5 percent of Britain's power in a private project, after the government rejected publicly funded proposals two years ago.

The Corlan Hafren consortium, made up of four companies including construction consultants Arup and Mott MacDonald, has presented new plans for a barrage in the Severn to the energy ministry, a spokesman for the government said.

A barrage would stretch across the estuary, like a dam, and use sluice gates to channel water, which turns turbines as it flows inland during high tide and back out during low tide.

"We have only seen a very draft and high-level outline business case from the consortium. Even if this proposal can meet our criteria, it has a long way to go in development," the spokesman said.

Corlan Hafren said its proposed barrage would generate 16 terawatt-hours of electricity a year and could operate for 120 years, but it gave no price estimate.

The Department of Energy and Climate Change (DECC) rejected a series of Severn project proposals in October 2010, saying a dam of up to 13,500 megawatts in capacity, bigger than the current proposal, could cost as much as 34 billion pounds ($53.4 billion), too much for the public purse.

In a report last year about Britain's future renewable energy market, the ministry said that even though it had rejected the Severn proposals for public funding, developers were assessing a number of privately funded projects in the area.

Environmental groups are in two minds about the tidal project, saying that even though they support the generation of renewable energy, more studies were necessary to establish the impact on fish populations. ($1 = 0.6368 British pounds)

(Reporting by Karolin Schaps; editing by Jane Baird)