Not a Drag ? Issues of Tidal Force in the Severn Estuary

Presentation Transcript

Not a Bore ? Issues of Tidal Power in the Severn Estuary Agenda University of the West of England 30 th June 2008

6 - 6.10 pm Introduction and Welcome Jim Longhurst and Eric Albone 6.10-6.40 pm Presentations Mervyn Bramley, Tom Appleby, Chris Spencer and David Bird 6.40 - 7.20 pm Discussion at Tables. One key issue for the Feasibility Study 7.20 - 7.30 pm Report Back on one key issue for the Feasibility Study 7.30pm Close AGENDA

Severn Tidal Power 'Not a Bore?' Engineering components and advancements Dr Mervyn Bramley Visiting research individual

Technologies – Tidal range and tidal stream Tidal stream innovation is currently at model improvement arrange Low head housed turbines as utilized as a part of tidal range floods and tidal ponds – e.g. La Rance – are creation innovation

From tidal range: Power ≈ k 1 A H 2 H = level distinction crosswise over torrent/tidal pond A = wetted surface region upstream of empoundment From tidal stream: Power ≈ k 2 V 3 V = mean free-stream tidal flow Potential tidal vitality catch

Prototype organize moving to full-scale showing Small business cluster up to 5 MW Large exhibit up to 30MW Potential obstruction with transportation paths Tidal stream exhibit

Impoundment by 9 km length bank Plan territory of 5km 2 Mean spring tidal range ≈ 8.5 m Installed limit 50MW Annual vitality yield 124 GWh Cardiff Weston flood ≈ 135 tidal ponds Estimated cost ≈ £250m tidal pond – Swansea

Cardiff – Weston Barrage Location: Lavernock Point to Brean Down Length: 16 km (10 miles) Generating limit: 8.6 GW or 8,600 MW Annual normal yield: 17 TWh or 17,000 GWh Percentage of UK power supply: 4.4% Estimated cost ≈ £15bn Tidal blast choices – diverse destinations

Concrete caissons towed to arranged establishments for sluiceways and turbines Some dike Shipping lock Connection to national framework Rail or street perhaps, yet adds extensively to width 200,000 man years of work – Site works Cardiff – Weston torrent A super building venture

Are the advancements adequately turned out to be connected at a huge scale in the Severn Estuary? Could the ecological effect of a Severn tidal plan both amid and after development be sufficiently alleviated? Could alternate employments of the Severn Estuary, specifically ports, business and transportation, be suited? Could the UK back and handle a venture of the measure of the bigger Severn flood recommendations? Can the carbon installed in a Severn tidal plan be sufficiently counterbalanced by the low-carbon control it produces ? Will we imagine a multi-practical plan and an oversaw evolving environment, or is this our scholar's stone? Issues for thought

'Not a Bore?' A Barrage of Legislation thomas.appleby@uwe.ac.uk Law Lecturer

How does the law see the estuary? Law sees it as land secured by water Needs assent of the proprietors of the seabed Otherwise mandatory buy necessities

Rights in the estuary Public appropriate to explore Public ideal to fish Private angling rights Private seepage rights

The impact of human rights Compensation for obstruction with those rights Difficult to evaluate at this stage

Environmental enactment Habitats Directive Severn hopeful 'Unique Area of Conservation' Requirement to shape compensatory natural surroundings for ensured highlights lost to power conspire

Capital designing expenses in addition to Compensation costs for individuals' rights Compensation for the earth Not that troublesome?

Severn Barrage 'Not a Bore?' Sediment Distribution and Flood Risk Sue Marriott and Chris Spencer

Sediment What sorts of residue exist in the estuary and how are they dispersed? Where does the silt originate from? Is the residue sullied? Surge chance Current issues

Sediment McLaren et al. 1993

How will the torrent affect on residue? Dissemination by tidal streams confined to Bristol Channel underneath blast Fine silt can settle in tidal pond behind torrent making water clearer, permitting bright entrance in this manner cleaner water in addition to photosynthesis and phytoplankton sprouts Contaminated dregs from floodplains may develop Build up of residue may diminish volume of upper estuary Sediments

Flooding What adds to surge hazard in the range? What will the impacts of the blast be? Tidal pond will raise water tables so waterway water may not deplete away so rapidly May bring about additional affidavit of mud in lower spans of streams because of lower angles diminishing limit Increased surge chance in lower reaches and backing upstream Flooding

Increased surge hazard upstream?

Sea-level ascent will have impacts on waterfront ranges because of expanded disintegration and expanded surge hazard Would likewise bring about moving down of stream water in lower achieves Barrage might be opened amid high waterway streams to move water out snappier Erosion vitality will be decreased behind blast Could a torrent alleviate against future ocean level ascent? Future Sea-Level Rise

Would a flood result in changes to dregs dissemination? Will changes have impacts in the Bristol Channel? What are the ramifications of brought water tables up in the encompassing territories? What is the probability of an expansion in defilement of estuarine silt? What are the probable effects on dregs and surge danger of other tidal power era alternatives? Expenses of additional seaside and surge safeguards required because of future ocean level ascent versus cost of flood? Issues for thought

Severn Barrage 'Not a Bore?' The Estuarine Ecosystem david.bird@uwe.ac.uk Environmental Biologist

Estuaries are one of the world's most gainful regular biological systems

Edible cockle ( Cerastoderma edule ) Baltic tellin ( Macoma balthica ) Ragworm (Hediste diversicolor) Lugworm ( Arenicola marina ) Estuaries bolster tremendous quantities of spineless creatures – yet couple of species

Mud snails ( Hydrobia ulvae ) – thickness may surpass 35,000 m - 2 Brown shrimp ( crangon ) evaluated populace ~ 10000 million shrimps Estuaries bolster enormous quantities of spineless creatures – however couple of species

1. Sand goby 2. Bass 3. Whiting 100+ fish species have been recorded from the Severn Estuary & Bristol Channel only 10 species add to 90% of all fish

Herring Sprat European eel River lamprey Important nursery for some marine species Used as a transitory passageway by a few animal groups

4,000 6,600 44,445 3,800 Golden plover ( Pluvialis apricaria ) Ringed plover ( Charadrius hiaticula ) Dunlin ( Calidris alpina ) Knot ( Calidris canutus ) Invertebrates & angle bolster a normal swimming winged creature populace of 88,500 people

Issues for thought: How would we adjust the requirement for vitality against the potential for ecological harm? The biological community won't be obliterated – however it will be changed – regardless? How would we put an esteem on animal types & biodiversity – are salmon more vital than lampreys?

The accompanying slides give a rundown of inquiries to the BERR Feasibility Study to address as planned by the members at the Not a Bore Science Café Event. Somewhere in the range of 85 individuals drawn from the Bristol hinterland went to the Science Café occasion held at the University of the West of England on 30 th June 2008. Taking after a progression of short scene setting presentations members talked about the ramifications of tidal power from the Severn estuary. Emerging from these discourses are a rundown of inquiries that the BERR Feasibility Study ought to address. Questions for the BERR Feasibility Study to Address

Will the assessment make correlation with the potential effect and contribution of other low carbon energies, for example, wind and sun based? Will the SEA evaluate the human expenses in the ranges taking after changes emerging from a vitality catch framework in the Severn? Given that environmental effect is a vital result of whatever framework is set up, as opposed to trade off why not go for the venture that delivers the most power and expands the low carbon vitality potential? Will the SEA assess such a situation? Why is tidal power from the Severn back on the political plan? Will the SEA and Feasibility Study consider suggestions for Human Rights? By what means will the proposed plans influence nearby groups? By what method will a tidal power plot advantage the South West? Will the favored plan be assessed against different types of renewable vitality? Is thought being given to littler group based vitality plans? By what means will the Feasibility Study guarantee that the chose tidal power plan won't be a white elephant? Questions for the BERR Feasibility Study to Address

How sure would we be able to be that the Feasibility Study procedure is not one-sided for a specific sort of innovation or size of plan and that it assesses the cost viability of non-tidal power other options to put the study's decisions in setting? What are the possible wellbeing effects of a torrent especially in development furthermore through expanded danger of flooding. How are the social angles/harm/change to be cost? The Severn bore is a one of a kind common marvel – in what capacity can a money related qualities be put on it? In the event that a flood is the favored choice by what method will adequate total be sourced to construct the structure? Will the Feasibility Study recognize the dependable gatherings to embrace ecological pay? What will be the effect of any plan on surge risks?  Will the surge situations considered really be thinking pessimistically? In what manner will the business impact on the Bristol's Docks be taken into a