A POPULAR scheme to harness a massive chunk of the UK's energy needs from the Severn estuary is back on track after receiving a "milestone" endorsement.

Cornwall engineer Rupert Armstrong-Evans says he is "delighted" the hydraulic principles behind his tidal "reef" concept have been given the thumbs-up by a panel of Government officials and technical experts.

The "reef", which Mr Armstrong-Evans conceived while in the bath, is one of a handful of schemes being considered by the Government for the Severn estuary, which has enough power locked within its tides to generate 5 per cent of the UK's energy needs.

As such, it would be the biggest renewable energy scheme in the world.

He feared the project would crumble as, 12 months ago, the scheme which could be the biggest civil engineering project in Europe was merely "sketches scribbled on the back of an envelope".

He was so frustrated with difficulties in getting to a £500,000 funding pot to develop the scheme that he considered handing over the intellectual property rights to the Government, making it a publicly owned asset.

His idea exploits the Severn's massive 45ft tidal range in a different way to other energy schemes. Put simply, it only uses a small difference in water level and so generates less power, but over a much longer period, causing less damage to wildlife.

A number of simple, low-head turbines would be placed along the 12-mile width of the Severn from near Minehead, West Somerset, to Aberthaw, Wales.

The principle has now been endorsed by the Severn tidal projects technical advisory committee, as well as engineering giant Atkins and a growing number of academics.

Conservation groups including the Royal Society for the Protection of Birds (RSPB) and the Wildlife Trust have put their weight behind the "reef".

When designing the wall of turbines, Mr Armstrong-Evans took into account the possible loss of thousands of hectares of natural habitat, the impact on fish and the costly time delays to ships travelling into Bristol port.

He is "more positive" about securing funding from the South West Regional Development Agency as talks continue. Money is needed to complete environmental research and expensive computer modelling, which could cost as much as £50,000.

A number of big-name engineering consultants are thought to be interested in taking the idea to proof of concept stage.

Mr Armstrong-Evans said: "I'm delighted it has got to this stage. I now know that if I dropped dead tomorrow, people could still take the idea forward.

"There is a long way to go. But now the baseline has been established I don't see why it can't go all the way. Unlike the other projects, it overcomes all the issues."

Mr Armstrong-Evans has also had a lift from a report by Atkins, commissioned by groups including the RSPB and the National Trust, suggesting the "reef" could generate more power than even he anticipated.

The Department for Energy and Climate Change is compiling a feasibility study which will inform Mr Miliband's decisions over whether or not to proceed. Estimates suggest it could cost up to £22 billion to build.

Mr Armstrong-Evans said the vast scale of the project means its creation could have an inspirational quality in the economic downturn.

He said: "It is the biggest civil engineering project in Europe. It is 20 times bigger than the scale of the Thames barrier. It would be a great way of making people proud of British engineering."