Severn Barrage: Not until after 2020 | Online news | New Civil Engineer

Energy minister Lord Hunt has said that any Severn Barrage scheme would be unlikely before 2020, and that costs for the shortlisted schemes could rise, with connections to the National Grid alone projected to cost some £2bn.

 

Speaking to the House of Commons’ energy and climate change committee, Hunt was answering questions about the proposed Severn Barrage schemes.

Hunt said that construction of a scheme by 2020 was unlikely. “You can construct a timetable for one of the smaller schemes so it could be operational by 2020,” but indicated that this would be tight, and committee member indicated their scepticism. Such a timetable would be simply impossible for the larger schemes, he said.

Hunt said that the five shortlisted schemes may not be a final list, and that rejected schemes could make it back on the shortlist once technology had caught up. “It might be that we have to go back to schemes in a couple of year to see whether the technology has caught up.

“But we want to see how far we can take this shortlist and move to a decision next year,” he said.

Hunt said that for some of the smaller schemes, private money alone fund them but the massive Cardiff-Weston barrage was simply too large. “Inevitably public finances would be used, especially for the Cardiff-Weston scheme because of the huge size and cost.”

Hunt added that existing subsidies for renewable energy schemes were not suitable for the Cardiff-Weston scheme, although one of the smaller schemes – presumably the Beachley Barrage – does fit existing criteria as its generating output is less than 1GW.

But the massive Cardiff-Weston Barrage would need a special kind of subsidy to work, as the costs are so high, Hunt said.

“The scale of the Cardiff-Weston Barrage is huge and would have great implications for grid infrastructure. Costs of conversion run to £2bn at least,” he said.

An aide to Lord Hunt indicated that a ‘smart grid’ would be needed to manage the times when the Barrage could produce power – determined by the tides, so often at inconvenient times.

She also said that the cost – approximately £21bn would; “Change because it would go up.” She said costs were based on studies carried out in the 1980s and 1990s and adjusted for today. A realistic cost would be calculated differently, and would be likely to increase outturn costs.

Hunt also said that the decision to build a Barrage would not determine whether the UK would meet its renewable power targets, and that: “I am confident we will meet the targets without this and we should not include a Severn scheme in planning to 2020.”

He said to include any scheme at the Severn would; “Preclude any decisions we make and we must decide this through the proper channels,” he said.

Hunt said other technologies such as carbon Capture and Storage (CCS) is; “Hugely important for this country,” and said he hoped a scheme would be in operation by 2020.

Finally Hunt said any scheme would carefully consider environmental impacts. “There will be impacts and if you cannot mitigate, then look at compensation. If that cannot be managed, then develop a scheme of equal environmental value. We could look at other parts of the country, with provision for species of equal value,” he said.

He said economic and environmental impacts would be given equal consideration, and that the ‘step change’ required by the Committee on Climate Change was already in action.

The five shortlisted schemes:

• 8.64GW Cardiff-Weston barrage, costing £20.9bn;
• 1.05GW Shoots barrage, costing £3.2bn;
• 0.625GW Beachley barrage, costing £2.3bn;
• 1.36GW lagoon at Bridgewater Bay costing £3.8bn
• 1.36GW lagoon at Welsh grounds, costing £4bn.

via Severn Barrage: Not until after 2020 | Online news | New Civil Engineer.

SETS Group selects SMEC Tidal Fence | tidal today

SETS Group selects SMEC Tidal Fence

The Severn Embryonic Technologies Scheme (SETS) Group has chosen VerdErg’s Spectral Marine Energy Converter (SMEC) for the Severn Estuary study.

The funding, to be matched by VerdErg, is supported by the Department for the Environment, Food and Rural Affairs, the Welsh Assembly Government, the South West of England Regional Development Agency, and the Department of Energy and Climate Change.

VerdErg has calculated that a SMEC Tidal Fence across the Severn Estuary will produce nearly as much electrical power as a full conventional Barrage, but at two thirds of the cost.

A full conventional Barrage, according to VerdErg’ MD Peter Roberts, is unsuited to the Severn Estuary because it permanently inundates three quarters of the intertidal wetlands behind it which are a vital habitat for millions of migratory birds.

“By complete contrast, an equivalent SMEC tidal fence preserves three quarters of this vital environmental resource. This is because the tidal flow is not trapped by a SMEC, as with a Barrage, but flows continuously through the device,” Roberts said.

Roberts believes that this development promises to be a major step in the development of the SMEC.

From VerdErg’s perspective, the ultimate aim of this work is to get to a point next Spring where SMEC has accumulated sufficient technical credibility to join the short list of candidate devices for an environmentally friendly source of renewable energy from the Severn Estuary.

“Part of this credibility will come from the experimental and analytical work we will do over the next six months and part from a “Road Map” which we will develop as one part of the study outlining our plans for subsequent development and commercial activity that will raise SMEC to a fully-established large-scale source of commercial renewable energy by around 2020, when the Severn Estuary installation is foreseen by the government,” Roberts told Tidal Today.

via SETS Group selects SMEC Tidal Fence | tidal today.

Severn tidal power scheme should not go ahead, warns Environment Agency | Environment | guardian.co.uk

Severn tidal power scheme should not go ahead, warns Environment Agency
The contentious Weston barrage would be the largest renewable energy project in Europe but comes with a huge ecological cost

John Vidal, environment editor guardian.co.uk, Friday 17 July 2009 15.01 BST Article history

A giant tidal energy scheme which the government is counting on to meet ambitious new green energy targets set this week should not be built because it would be so ecologically destructive, the chair of the Environment Agency has warned ministers.

The government’s roadmap to a low-carbon UK called for a 34% cut in emissions by 2020, with the power sector contributing the bulk of that saving. The Weston barrage, running 10 miles across the Severn estuary between Weston-super-Mare and Cardiff, is by far the largest of four tidal power schemes being considered by government and would be the centrepiece of the nation’s renewable energy plan.

It could generate 8.6 gigawatts of zero-carbon electricity from the Severn – the equivalent of eight large coal-fired power stations – and would be the single largest renewable energy project in Europe.

But the £5bn flagship scheme would permanently flood nearly 35,000 hectares (86,000 acres) of internationally protected wetlands. It would also destroy some of Britain’s most important fisheries in the Severn, Wye and Usk catchment areas, said Lord Smith in an interview with the Guardian.

“The great wall across the Severn channel poses the classic environmental dilemma. It would generate 5% of all the UK’s electricity needs but at a huge cost in terms of fishing and habitats. These immense environmental impacts outweigh the carbon reduction benefits which you would get. We are advising the government on this pretty strongly,” said the government’s chief environmental adviser.

“There must be ways of harnessing tidal power from the estuary without the gross impacts that the Weston scheme would have. I regret that we are not putting as much effort as we could into tidal reefs and defences. We should be addressing the possibility of tidal power around the country. Tidal energy should be one of the key ways of generating electricity”, he said.

Smith’s comments will not be welcomed by the government which this week committed itself to generating 20% of the UK’s energy from renewable sources within only 11 years, but it is meeting technical and planning delays with wind power.

A decision on the barrage will be given next year but ministers are keen to see it started because it would contribute more to emission cuts than any other scheme. The energy minister, Lord Hunt, said this week: “The Cardiff-Weston barrage has the potential to save the equivalent of the yearly CO2 emissions from all homes in Wales.”

The barrage, which would be a huge engineering feat on the scale of some of the world’s biggest construction projects, is shaping up to be one the most contentious environmental issues of the decade. The National Trust, the RSPB and WWF, together representing more than 5 million people, have said that a barrage would be “economically dubious” and “ecologically disastrous”.

They have also argued that 5m tonnes of CO2 would be emitted during construction and another 5m tonnes during transport of the materials, undermining claims that the barrage would help reduce emissions.

Smith also warned the nuclear industry, another part of the energy and climate change secretary, Ed Miliband’s “trinity” of low-carbon electricity plans, that climate change could seriously affect their costs. He said the agency would demand that nuclear power companies build major sea defences to protect nuclear power against the sea level rises expected over the next 100 years.

“Virtually all the new [nuclear] stations are by the sea. We will look at them on a case-by-case basis but all sites must be fully defensible. The power companies know that they will have to defend them on a very large scale. Protection against flood risk must be absolute.”

Smith also questioned Miliband’s intention to preserve low-cost mass air travel, revealed in the Guardian this week. Calling for a debate on the future of aviation, he argued that climate change made it doubtful people could fly so much in 40 years’ time. “By 2050 we should have reduced greenhouse gases by 80%, which means we will have 20% left. How much of that 20% should be taken by aviation?

“Aeroplanes will get more efficient but they will not be able to completely remove their carbon emissions. By 2050 we will need to have decided how much flying we can do. “

via Severn tidal power scheme should not go ahead, warns Environment Agency | Environment | guardian.co.uk.

Huge barrage plan makes estuary shortlist – Green Living, Environment – The Independent

Huge barrage plan makes estuary shortlist

By Emily Beament, Press Association – Monday, 26 January 2009

A 10-mile barrage across the Severn is among five projects on a shortlist for potential schemes to harness the tidal power of the estuary published by the Government today.

 

Two innovative “lagoon” schemes, which would impound a section of the estuary without damming it, and two smaller barrages are also on the list.

Publishing the proposed shortlist today, Energy and Climate Change Secretary Ed Miliband said ministers had not “lost sight” of other innovative plans, including a huge “reef” project and tidal fences, which had been on a list of 10 schemes under consideration.

He announced £500,000 of funding to develop the new technologies such as the tidal reefs, which supporters say could harness the power of the estuary without causing the environmental damage associated with a barrage.

And he said progress on those technologies would be considered before any final decisions on a tidal power scheme for the Severn estuary were made.

The proposed shortlist, which is now being put out to public consultation, is as follows:

* The Cardiff-Weston barrage – a 10-mile scheme stretching from near Cardiff to near Weston-super-Mare which could generate up to 5 per cent of the UK’s energy needs;

* Shoots barrage – a scheme further upstream which would generate around 1GW, equivalent to a large fossil fuel plant;

* Beachley barrage – an even smaller scheme, just above the Wye River, which would generate around 625MW;

* Bridgwater Bay lagoon – a proposal which would impound a section of the estuary on the coast between east of Hinkley Point and Weston-super-Mare, which could generate 1.36GW;

* Fleming lagoon – a similar scheme which would generate the same amount of power from a section of the Welsh shore between Newport and the Severn road crossings.

 

The Severn, which has the second-largest tidal range in the world, has the capacity to provide significant amounts of “green” electricity but conservationists fear some of the plans for the estuary could be hugely damaging to wildlife.

For example, the Cardiff-Weston barrage could destroy between 11,000 and 15,000 hectares of saltmarsh and mudflats, which under European law would have to be replaced with compensatory habitat elsewhere at an estimated cost of £1 billion to £3 billion.

Mr Miliband said there were tough choices to be made in fighting climate change, the “biggest long-term challenge we face”.

“Failing to act on climate change could see catastrophic effects on the environment and its wildlife, but the estuary itself is a protected environment, home to vulnerable species including birds and fish,” he said.

“We need to think about how to balance the value of this unique natural environment against the long-term threat of global climate change.”

He went on: “The five schemes shortlisted today are what we believe can be feasible, but this doesn’t mean we have lost sight of others.

“Half a million pounds of new funding will go some way to developing technologies still in their infancy, like tidal reefs and fences.

“We will consider the progress of this work before any final decisions are taken.”

A tidal fence project over part of the Cardiff-Weston line with tidal stream turbines to harness the ebbing and flowing tides, and a reef proposal on the line of the outer barrage, which would have included floating turbines, were on the long list but not today’s shortlist.

The biggest barrage proposal, an “outer barrage” which would have stretched from Minehead to Aberthaw, has not been included in the shortlist.

Neither has a barrage which would have been similar in size to the Cardiff-Weston scheme but would have landed at Hinkley rather than Brean Down on the English side.

And a 0.6-mile (1km) wide barrage on the Cardiff-Weston line, which would have had a wave farm and four marinas, has also been left off.

All 10 projects from the long list, and the proposed shortlist, will now be subject to a three-month consultation, after which the Government will publish a final shortlist.

Those five projects will be considered in more depth, with a view to making a final decision on how best to harness the energy of the Severn estuary in 2010.

 

The two-year multimillion-pound feasibility study by the Government aims to assess the costs, benefits and impacts of a tidal scheme in the Severn and identify a single preferred project from the options that have been proposed.

Welsh Assembly Government Environment Minister Jane Davidson said: “Harnessing the power of the Severn estuary ties could make a significant contribution towards achieving the UK targets for renewable energy and reducing carbon emissions, but we must ensure that environmental issues are taken fully into account.

“The shortlisted schemes are based on relatively well understood hydroelectric technologies, with a mix of existing and new engineering structures.

“It is proposed that the economic, social and environmental impacts of these be studied further in the second phase of the Government study.”

The barrage proposals in particular have attracted controversy, with conservation groups concerned over the level of environmental damage they could do.

A study for the RSPB suggested the 12-mile “reef” could be cheaper and less damaging to wildlife than a barrage.

While a barrage would effectively dam the estuary, flooding huge areas of tidal habitat upstream of the construction, the reef would not hold back the full height of the tide and therefor have less impact on those sites.

Martin Harper, head of sustainable development at the RSPB, said: “It is hugely disappointing to see Government still pushing forward with the environmentally destructive option of a Cardiff-Weston barrage.

“We believe the focus should shift to innovative and potentially less- damaging alternatives like a tidal reef or tidal fence.

“The announcement of £500,000 to develop these schemes is very welcome, but it makes no sense to leave them off the shortlist.

“By excluding them, Government is excluding what could be the most environmentally benign options from its assessment of environmental impacts.”

Natural England, the Government’s conservation agency, said it was right to consider harnessing the power of the Severn estuary.

But the project should not go ahead without a detailed consideration of its environmental impacts and and a wider assessment of whether there were better ways to meet the drive towards renewable energy.

Helen Phillips, Natural England’s chief executive, said: “We cannot sacrifice an environment as sensitive as the Severn estuary without resolving, once and for all, whether there are better alternatives.

“We need to look at renewable energy and energy conservation in the round and satisfy ourselves that tidal power in this area – with all the environmental consequences that go with it – really is the best route to take.”

The Wildlife Trusts expressed concern that schemes where shortlisted at an early stage in the feasibility study, warning that it favoured proven technology – barrages – which would be highly damaging environmentally.

The Trusts said a barrage would destroy habitat on which species of bird such as shelduck, dunlin, redshank, teal, European white fronted geese and pintail depend.

Migrating fish species, such as salmon, trout and eel, would also be at risk.

The Trusts acknowledged the Government’s commitment to funding for innovative technologies but said less environmentally damaging schemes such as the reefs should have made it on to the shortlist.

 

Mr Miliband and Ms Davidson presented the shortlist this morning at a stakeholders conference in the hands-on science museum in Bristol.

They were joined by minister of state for the DECC Mike O’Brien MP.

Addressing concerns that a number of the schemes would have a detrimental impact on the bio-diversity of the Severn estuary, Mr Miliband told a press conference: “The impact of catastrophic climate change, or dangerous climate change on biodiversity is extremely significant.

“If you had water levels rising by a metre for example, that would have a very bad, very negative effect on the Severn estuary.

“There are issues, of course, around the local environmental effects of the kind of technologies that are on the table.

“But I think you also have to take into account the wider climate effects and their potential impact on biodiversity. That’s part of the process we are embarking upon.

“Of course climate change is overwhelming and important, but part of the next stage of the process is specifically looking at the biodiversity impact and the compensatory measure that might be necessary.”

 

While coastal tidal lagoons were included on today’s shortlist alongside the more conventional barrage proposals, Friends of the Earth Cymru criticised the Government’s failure to pursue offshore lagoon proposals.

Friends of the Earth Cymru director Gordon James said: “Offshore tidal lagoons offer the best option for harnessing the huge renewable energy potential of the Severn estuary – their exclusion from the Government’s shortlist is utterly incomprehensible and raises serious concerns about the consultation process.

“The development of tidal lagoons would have delivered huge quantities of green power more cheaply and quickly than a barrage, and with less impact on the environment.

“Ministers must abandon their fixation with the Severn barrage and invest in more effective and less damaging alternatives instead.”

via Huge barrage plan makes estuary shortlist – Green Living, Environment – The Independent.

Barrage plan gets mixed reaction from environmental groups – New Civil Engineer – 29 Jan 2009

• Published: 29 January 2009 11:31
• Author: John McKenna

The Severn Barrage’s inclusion on the government shortlist of tidal power schemes being considered for the Severn Estuary this week got a mixed reaction from green groups.
The Green Party and the Royal Society for Protection of Birds (RSPB) criticised the government for backing the scheme which they claim will destroy the natural habitat of thousands of birds.  But the Sustainable Development Commission (SDC) welcomed the shortlist.
The 8.64GW Cardiff-Weston scheme could potentially provide 5% of the UK’s electricity as renewable energy. But it would also destroy up to 60% of the estuary’s 20,000ha inter-tidal habitat – according to Friends of the Earth Wales.

“Harnessing the tidal power of the Severn has to be right, but it cannot be right to trash the natural environment in the process,” said RSPB head of sustainable development Martin Harper. “We know the Cardiff-Weston Barrage would destroy huge areas of estuary marsh and mudflats used by 69,000 birds each winter and block the migration routes of countless fish.”

But SDC chairman Jonathon Porritt said the barrage’s environmental benefits could outweigh  wildlife considerations. “Faced with the problem of decarbonising our energy supply, the potential prize to be gained from harnessing the power of the Severn in terms of secure and low-carbon energy is one which we cannot afford to ignore,” he said. “The draft shortlist contains an imaginative but feasible list of proposals, combining a range of smaller options which could be realised sooner, and larger ones which could provide more energy, but take longer to become reality.” “The final scheme must be the one that generates as much clean energy as possible while minimising harm to the estuary and its wildlife.

Friends of the Earth criticised the government for failing to include offshore tidal lagoon schemes in its shortlist. 

BARRAGE IMPACT
Habitat loss 

• Cardiff Weston: 20,000ha
• Shoots Barrage: 5,000ha
• Beachley Barrage: 3,500ha
• Russell Lagoon: 6,500ha
• Bridgwater Bay: 5,500 ha  

 

 

via Barrage plan gets mixed reaction from environmental groups.

“The Government should not rely on the Severn Barrage project” | tidal today

“The Government should not rely on the Severn Barrage project”

Published on Nov 4, 2008

A new report from the House of Lords European Union Committee has indicated that Britain will be unable to reach its target for renewable energy by 2020 without “wholesale changes on all fronts” to its current strategy.

The Committee mentioned that the plan to build a barrage across Severn near Bristol will not help the Government meet its renewable energy targets.

It is estimated the £15bn barrage could produce five percent of Britain’s electricity or 1.5 percent of its total energy use. Yet the House of Lords EU committee concluded the barrage would not be built in time. If a barrage is approved, construction is likely to start in 2014 with an estimated completion date of 2023.

The Lords’ report stated: “Should the Severn barrage be built, it may still not be completed in time to contribute to the 2020 target. It is necessary to await the economic, technological and environmental assessments for the Severn barrage project before decisions can be made about whether it can be included as a deliverable resource.

The Government should not rely on inclusion of the estimated generating capacity of the barrage to reach the 2020 renewable target.”

A Stop the Barrage Now spokesman said: “The report highlights the growing concern among our supporters that the Government has become fixated on a barrage scheme that is incredibly costly in the first instance, is an environmental nightmare to the estuaries wildlife and biodiversity, and will be extremely damaging to the region’s economy – especially the maritime community.”

via “The Government should not rely on the Severn Barrage project” | tidal today

Severn barrage debate | from www.nce.co.uk

Severn barrage debate
Published: 15 May 2008 15:01 Author: John McKenna

Answering the environmental critics will be the toughest test that the Severn Barrage is likely to face.
Like scribbling a note on the Mona Lisa. This is how Environment Agency chief executive Barbara Young described the environmental impact of the construction of a tidal power barrage across the river Seven estuary (NCE 8 November 2007).

Young’s opinion that a £14bn structure between Cardiff and Weston-Super-Mare harnessing the tidal power that lies in the estuary is too environmentally expensive is one shared by most green groups.

The estuary’s 14m tidal range is the second highest in the world. This range is a potentially huge resource of tidal power.

But it also creates a natural phenomenon like the Severn bore – a wave which travels up the Severn during Spring tides – and has made a wetland habitat of mud flats and salt marshes, claimed by English Nature and the Royal Society for the Protection of Birds (RSPB) to be unique.

AdvertisementHome to a number of species of wading birds considered of international importance, the estuary is a designated Special Protection Area under the European Birds Directive.

The Department for the Environment Food and Rural Affairs (Defra) has also asked the European Commission to consider the Severn Estuary as a possible Special Area of Conservation under the European Habitats Directive.

The proposed 8.64GW Cardiff-Weston barrage is essentially a concrete dam stretching 10km across the estuary, with sluice gates allowing water to flow into the Severn’s tidal basin at high tide.

This water would be impounded until the tide on the coastal side of the barrage had reached its lowest point. Impounded water would then be released through turbines to generate electricity.

“Three times the amount lost would need to be created in compensatory habitat in order to ensure the birds took to it and did not migrate elsewhere”

Peter Jones, RSPBIt is anticipated that construction could destroy up to 60% of the estuary’s inter-tidal habitat – 260ha according to Friends of the Earth (FoE) Wales – as it would be submerged in water held behind the barrage.

“At least three times the amount lost would need to be created in compensatory habitat in order to ensure the birds took to it and did not migrate elsewhere,” says RSPB Wales environmental policy officer Peter Jones.

He was speaking at last week’s ICE Wales Severn Barrage conference. Based on FoE Wales’ figures, this would mean roughly 780ha of wetland habitat would have to be created.

“This could be the showstopper [for the Severn barrage],” says Sustainable Development Commission (SDC) commissioner for Wales Peter Davies, who also spoke at the ICE Wales conference.

Last year the SDC released a report concluding that a barrage was the best option for harnessing the tidal power in the Severn Estuary, pre-empting the Department for Business Enterprise and Regulatory Reform’s (BERR) two-year feasibility which began in February.

However, despite the SDC’s broad support for a barrage, Davies says the BERR study will need to answer three critical questions if it is to be able to justify the construction of a Cardiff-Weston barrage.
“Firstly, are there alternatives?” he asks.

“Secondly, is it in the overriding public interest? And thirdly is there compensation [for loss of habitat]?”

The first of these challenges looks as though it may be the easiest to answer: BERR has stated that it only wishes to look at renewable energy technologies that make use of the Severn’s tidal range.

This leaves the door open for only two established tidal power technologies: tidal lagoons and tidal barrages. A tidal lagoon is a circular concrete cofferdam which allows water in through sluice gates as the tide comes in. It then holds the water until low tide when it is released, generating electricity.

The SDC report concludes that tidal lagoons should be avoided as their effectiveness is unproven, but speaking at the ICE Wales conference, BERR Severn Tidal Power Feasibility Study deputy director Gary Shanahan said that no decision on the type of technology to be used had been made. But he later added that BERR wanted to avoid taking risks on emerging technologies.

“Additional risk will be factored into the cost, so you have to be careful how much innovation you put in,” said Shanahan.

With the emphasis on proven technology, a barrage is looking increasingly likely. The Rance tidal barrage in Brittany, France has, after all been operating successfully since the 1960s.

Answering the question on alternatives therefore becomes a simple choice between the Cardiff-Weston barrage and the proposal for the smaller “Shoots” barrage further upstream.

This uses the same technology as the Cardiff-Weston proposal, but on a smaller scale. It would be located where the Severn is narrower and cost £1.65bn to build. Generation capacity would be 1.05GW.

Its impact on tidal levels downstream would be minimal, so environmental groups prefer it. But the Shoots proposal could be unstuck by another critical factor: is its construction in the overriding public interest?

In January, the European Union set Britain the target of generating 15% of its total energy demand – including transport and heating – from renewable energy sources by 2020, up from the current 2%.

To meet the target, it is anticipated that anything between 35% and 50% of the UK’s total electricity demand will have to come from renewables.

Given that the Cardiff-Weston barrage is projected to provide the equivalent of 5% of UK electricity demand, it looks likely it would meet the public interest criteria more comfortably than its smaller competitor.

But the issue then will be creating new habitats to compensate for those lost to the barrage. “It will be test three, on compensation, that will be difficult,” says Davies.

It will be this question of compensation for lost habitats that will dominate the investigations of the consultant which carries out the Strategic Environmental Assessment contract – the first contract, shortly to be awarded, from BERR’s study.

Compensation on the scale being suggested is not without precedent: consultant Faber Maunsell was appointed in October to design a new 736ha wetland environment at Wallasea Island, Essex – the largest scheme of its type in Europe (NCE 9 October 2007). At £12M, the project, funded by the Royal Society for the Protection of Birds (RSPB), shows that a compensatory habitat for the Severn estuary would be cheap compared to the £14bn construction cost of the barrage.

Author: John McKenna. News Editor

http://www.nce.co.uk/energy/2008/05/severn_barrage_debate.html

Government reveals Severn tidal power schemes being considered | from www.nce.co.uk

Government reveals Severn tidal power schemes being considered
Published: 24 July 2008 10:55 Last Updated: 24 July 2008 10:55

The Government yesterday published a list of 10 proposed projects that it is considering in its investigation into tidal power in the Severn Estuary.
Under the Strategic Environmental Assessment of the Department for Business, Enterprise and Regulatory Reform’s (BERR) ongoing feasibility study, managed by consultant Parsons Brinckerhoff, the 10 proposals will be examined and whittled down to a shortlist to be published later this year.

“Harnessing the power of the Severn Estuary could be an engineering
project of breathtaking scale and we will look at the full range of
technologies and locations,” said Business secretary John Hutton, revealing the potential schemes at a meeting of stakeholders in Cardiff yesterday.

“Such a project could play an important role in our ambition to
dramatically increase the amount of energy from renewable sources.
The tidal range on the Severn is the second largest in the world and
has the potential to provide around 5% of the UK’s current
electricity demand.”

The ten projects being considered for Government backing are:

Outer Barrage from Minehead to Aberthaw: this would be the largest barrage and would make maximum use of the Severn Estuary tidal resource

Middle Barrage from Brean Down to Lavernock Point: most
well-studied option, known as the Cardiff-Weston barrage

Middle Barrage from Hinkley to Lavernock Point: as option 2 but
lands at Hinkley

Inner Barrage (Shoots Barrage): also known as English Stones
scheme and studied in detail by the Sustainable Development
Commission

Beachley Barrage: barrage further upstream, smaller generating
capacity than Shoots

Tidal Fence proposal: a barrier constructed over part of the
Cardiff to Weston line, with open sections, incorporating tidal
stream turbines to capture energy from the ebb and flood tides

Lagoon enclosure on the Welsh grounds (Fleming lagoon): one of the previously studied Russell lagoons from 1980s

Tidal lagoon concept: a proposal for a number of tidal lagoons

Tidal reef proposal: a concept that would include floating
turbines and caissons

Severn Lake Scheme: a 1 km wide barrage in the same location as
the Cardiff-Weston scheme designed to allow the construction of a number of additional features, including a wave farm on the seaward side and four marinas

“The aim of the joint feasibility study is to look at all the potential options for generating renewable and sustainable energy
from the huge tidal range of the Severn estuary,” said Welsh Assembly Government Environment, Sustainability and Housing minister Jane Davidson.

“It is important to stress that while there is much talk of a ‘barrage’ this feasibility study is looking at a range of other options.”

http://www.nce.co.uk/energy/2008/07/government_reveals_severn_tidal_power_schemes_being_considered.html

Severn Barrage | from “New Civil Engineer” www.nce.co.uk

Published: 29 July 2008 18:32 Author: John McKenna More by this Author Last Updated: 04 November 2008 19:06 Reader Responses

After over 100 years of proposals, the Government is finally seriously considering the construction of a tidal barrage across the Severn Estuary.

First proposed in 1840, the scheme really gained momentum in 1981 when a group of contractors, known as the Severn Tidal Power Group(STPG), carried out engineering and environmental studies into a 16km barrage spanning the Severn between Cardiff and Weston-Super-Mare.

STPG’s findings were published jointly with the Government in 1989, but subsequently fell from consideration following privatisation of the electricity industry in 1990.

Harnessing the massive renewable energy resource that is the tidal range of the Severn Estuary, at 14m the second largest in the world, has again hit the political radar thanks tp the combined forces of European renewable energy targets and rocketing oil and gas prices.

In September 2007, Business secretary John Hutton announced that the Government would be running a two-year feasibility study into tidal power in the Severn Estuary, exploring a number of technologies including several barrage proposals.

Two contracts have so far been awarded under the feasibility study: a consortium led by consultant Parsons Brinckerhoff is managing a Strategic Environmenta

via Severn Barrage