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Severn Barrage

rose to call attention to the case for the construction of a Severn barrage, its environmental impact, and other options for electricity generation in the Severn estuary; and to move for Papers. The noble Lord said: My Lords, the purpose of this debate is to attempt to move forward with greater urgency the need to capture electricity from the Severn estuary. The fact that this site has the second-highest tides in the world is a huge incentive. I have no luddite tendencies in securing this debate. I do not say no to electricity generation in the Severn estuary and the Bristol Channel, but I seek answers to questions of how best this is to be achieved. The reduction of fossil fuel use and carbon emissions remains paramount in driving this issue forward. At the start, it is best to summarise how tidal energy can be classified and captured from the Severn estuary as follows: first, tidal range, which is the normal ebb and flow of the tide and, secondly, tidal streams—flows of water at different depths and geographical locations. On tidal range, there are two methods of tidal energy capture from turbines in the Severn estuary: first, the Severn barrage—an obvious one—and the construction of tidal lagoons is the second option. The capture of energy by tidal stream turbines occurs at varying depths. The big question is: what is the best method to generate electricity? This question gives rise to a range of additional questions for which it is highly desirable to have accurate answers. What are the relative capital costs of construction of different tidal electricity plants? What is the return on capital invested on different electricity generation systems? What additional rates of return will be achieved on more rapidly built systems? What will be the comparative lead-in time before electricity is generated from different systems? What impact will this have on increasing production of renewable energy sooner to reduce carbon emissions? What will be the relative cost per unit of electricity produced from different methods of generating electricity from tidal power? What are the relative environmental impact differences between systems of producing tidal electricity? Regrettably, we do not yet have the answers to all these questions. Because work has been done on the concept of a Severn barrage for many years, we know that at current prices it will cost some £15 billion and produce up to 5 per cent of UK energy, and that the build-time is variously estimated to take from eight to 12 years. We know also that there are two possible sites for the barrage. The most canvassed site is the Cardiff Lavernock Point to Weston-Super-Mare barrage, or there is the Shoots barrage, just downstream of the second Severn crossing. A vast amount has been published on the barrage, but the main Sustainable Development Commission report, Turning the Tide—Tidal Power in the UK, published on 1 October 2007, contains what purports to be a more independent assessment of a proposed Severn barrage than some other assessments. In particular, this study looks at alternatives to the barrage, with tidal stream and tidal lagoon technology. In summary, the SDC report details and reviews the options: Severn barrage, tidal stream and tidal lagoon. The report does not attempt to calculate the extent of the carbon footprint of the construction of the barrage, nor does it solve the economic problems of the closure of Bristol, Newport and Cardiff docks, or those of Gloucester. Nor does it address the considerable cost of establishing large new wildlife sites. The European directives concerning habitats on the Severn estuary state that it has an important number of international conservation sites. It is designated as a special protection area for avian features under the EU bird directive and as a possible special area of conservation. SAC status also applies to the River Usk, the River Wye and the Mendip limestone grasslands. There are local conservation sites too, including 26 SSSIs, one national nature reserve, eight local nature reserves, one historic landscape and four wildlife trusts. There are many local biodiversity action plans for habitats and species. This is especially important for Severn fish species and many water birds. According to the SDC report, allis and twaite shad, river and sea lampreys and Atlantic salmon face the prospect of extinction. That applies particularly to the winter and spring run of Atlantic salmon. The SDC concludes: "““A Severn barrage must be publicly led as a project and publicly owned as an asset to avoid short-termist decisions and ensure the long-term public interest""Full compliance with European Directives on habitats and birds is vital, as is a long-term commitment to creating compensatory habitats on an unprecedented scale""Further investigation of the ‘environmental opportunity’ that might exist for combining climate change mitigation with ""adaptation through a habitat creation package that actively responds to the impacts of climate change over the long term""Development of a Severn barrage must not divert Government attention away from much wider action on climate change.""By taking this approach it would be possible to combine a climate change mitigation project (the barrage) with climate change adaptation, by developing compensatory habitats that reflect our changing climate, and combining this with coastal protection and other climate change strategies, thus creating an ‘environmental opportunity’””." The report also states that there is tidal stream and tidal range. It defines that and says that it, "““could supply at least 10% of the UK’s electricity if fully exploited, around 5% from each resource””," and that—I speak as a Welsh Member— "““50 per cent of this resource is in Wales.""There is minimal conflict between the exploitation of tidal stream and tidal range resources, or between the technologies that might be deployed. The best tidal stream sites are in the north of Scotland, with significant potential also around north Wales””," and of course there are some in the Severn estuary as well. The report states that: "““The UK has an excellent tidal stream resource, and is leading the world in the development of a wide range of tidal stream devices, several of which are at the testing stage. The UK must ‘stay the course’ in developing these technologies, as the export and climate change benefits are potentially very large””." The noble Lord, Lord Crickhowell, who is unable to be here today, made these points in his speech on the Queen’s Speech. The report goes on: "““Despite the encouraging progress made so far, Government could do more to assist these emerging technologies, particularly through flexible financial support, and by providing additional resources to the European Marine Energy Centre in Orkney.""On tidal lagoons, the SDC found that there is a lack of available evidence on the costs and environmental impacts, mainly due to the absence of any practical experience””." These are the main relevant conclusions of the SDC in relation to this topic. However, some criticisms can be made of the SDC report. It used five desk-based research reports rather than carrying out any new work. More new work would be needed, as much of the evidence used dates from the 1980s. Further, the report devotes more than half its pages to the Severn barrage; the report may be about tidal power but the focus is certainly on the Severn barrage. In addition, financing the project needs further explanation—that is very true indeed. Several other points need to be made in relation to the SDC report. First, the estuary is at risk from fluvial flooding and a barrage would have a significant impact on the rivers and watercourses that discharge into the estuary. The levels on both sides of the estuary rely on drainage systems storing fluvial water during high tide periods, which is quite a good point. Also, it is not exactly clear who would own the plan for the Severn barrage and thus be responsible for the appropriate assessment under the habitats regulations. The £15 billion cost, which I previously mentioned, relates to construction. There would clearly be considerable additional costs relating to feasibility studies, environmental impact, strategic environmental assessment and habitats compensations. Those are all points which could have been made clearer in the SDC report. However, others have made some points which concern them. The Severn Tidal Power Group represents the main contractors who would be involved in the construction of the Severn barrage. It understandably welcomes the SDC report—a large project like the barrage would of course benefit it, and one suspects that the report’s indication that either tidal lagoons or tidal stream turbines are a little way off in development terms will encourage it in its view. However, it indicates that the coming study should examine all options and views. Another body that is contributing to the debate and has an interest in the outcome is Tidal Electric Ltd, which has drawn up a number of points that are worth repeating—in its favour, I hasten to add. It has drawn up a table with the Severn barrage on the left hand side and tidal lagoons on the right. It says that the Severn barrage will be publicly funded, which it estimates at £15 billion to £25 billion capital costs, versus private funding. Its estimate for the production of electricity is 3.5p per kilowatt hour. It further suggests zero costs to HMG, plus taxed revenue, because tidal lagoons would be privately financed and carried out. It says that one would be environmentally damaging and the other environmentally benign; that one would destroy wildlife habitats while the other would create wildlife habitats; that one is opposed by environmental groups while the other is supported by them; that one would give flood protection upstream while the other would mean flood damage downstream; that there is a 10 to 15-year rollout for the barrage versus a two-year rollout, although I suspect it might be more than that; that further HMG-funded studies are proposed versus being ready to build on receipt of consent; and so on. Those are the benefits that it says that its system of lagoons would have over the barrage. Tidal stream technology is going ahead and being assessed at present. That has large potential. Both tidal lagoons and tidal streams are estimated to be able to produce the same amount of electricity—some claim more—than would the Severn barrage itself. Capital costs of the Cardiff-Weston barrage would be £15 billion; to produce the same amount of electricity with tidal lagoons would be £5 billion. Tidal stream would be £6 billion plus a necessary grid connection costing £4 billion, taking the total to £10 billion. There are very varying estimates as to how much the electricity would cost from the output of these different systems. Cardiff-Weston is 3.6p per kilowatt hour, depending on which discount rates were used—it goes up to as high as 22p per kilowatt hour, with a mean of about 12p. Tidal lagoons would be 3.3p per kilowatt hour according to Tidal Electric, but 17.2p per kilowatt hour according to DBERR, so there is a big difference there. Tidal stream has been estimated to be at 2.5p per unit. In conclusion, varying information is coming from divergent sources as to the final electricity costs with different modes of electricity generation. The basis of the proposed Severn barrage is the La Rance barrage in Brittany, looking at design, construction, costs and calculations and the electricity output at sale. At 40 years of age, it is old technology but that is the basis, because it is a tested system. But we must ask ourselves why the French have not put in another La Rance barrage and why the Canadians rejected a barrage for their new tidal electricity initiative. Undoubtedly, tidal stream technology could produce as much, if not more, electricity than the Severn barrage and the results of running this plant are emerging from work taking place in the Orkneys at present. Tidal lagoons have considerable potential and could at least equal the Severn barrage in their electricity output. However, it is vital that the Government grant a licence to commence the construction of a working lagoon model in Swansea Bay which would produce accurate data for comparison. Generating electricity from tidal power in the Severn estuary is a massive opportunity. Will the Government meet the challenge and have the wisdom to see that there is an alternative vision to a barrage, one which has the potential to produce just as much electricity and eventually more? The rewards for this are the creation of an entirely new and innovative tidal power industry in tune with carbon reduction objectives, a green industry with worldwide multi-billion pound export opportunities for British-built technology, and the creation of real, high-value, long-term jobs here in Britain. All that is required is for the Government to kick-start it. In doing so, they would also be saving for future generations one of the most important environmental sites in these islands. I beg to move for Papers.