Title: Environmental Impacts of Tidal Technologies Morgan Parry Head of WWF CymruWales
1Environmental Impacts of Tidal TechnologiesMorga
n ParryHead of WWF Cymru/Wales
2(No Transcript)
3Global temperature trends
Data IPCC
4from Stern Report
5Predicted sea temperature rise
2020s
2050s
2080s
High Emission scenario, produced by Tyndall and
Hadley Centres for UKCIP
6Past and Predicted Variability in Ocean pH
Past (from Pearson and Palmer, 2000) and
predicted (from Turley et al. 2005) variability
of marine pH. Future predictions are model
derived values based on IPCC mean scenarios. The
error bars indicate the likely seasonal scale
variability in pH.
7Zooplankton
8Trophic cascade and mismatch
Space
Phyto- plankton
Zoo- plankton
fish
birds
Time
9Simplified Food Web for the NW Atlantic
www.fishertcrisis.com/coral.html
10Electricity supply mix
Source DTI Energy Review Consultation Document
11Marine in the renewables mix
Source Oxera modeling for DTI Renewables
Innovation Review, 2003
12Modular devices
13Tidal fence
Tidal lagoon
14La Rance tidal barrage, Brittany
15Tidal lagoon design
16Emissions and Materials Consumption
- Cradle to grave assessment required
- Tidal Stream Energy devices shorter construction
time, pay back quicker. Steel in construction
is energy intensive but less aggregate and
concrete - Tidal Lagoons very high aggregate demand but
little ancillary infrastructure - Tidal Barrages large material requirement,
transport and ancillary infrastructure e.g.
roads, port facilities long pay-back time
17Species and Habitat Impacts
- Tidal Stream Energy devices environmental
appraisals currently being carried out on
individual devices. Fish and mammals may avoid
them, acoustic deterrence possible - Tidal Fences greater obstacle to fish and
mammals than individual devices, but not complete
barrier like barrage - Tidal Lagoons fish and mammals may avoid the
area but risk of fish entrapment during flood
generation - Tidal Barrages reduce tidal range creating a
loss of habitats. Water quality reduced if
dispersal/dilution inadequate. Barrier to fish
movements
18Sediment Flow
- Tidal Stream Energy devices current turbines
currently being modelled in Strangford Lough and
elsewhere - Tidal Fences considerable reduction in energy of
water column but less than barrage - Tidal lagoons currents and wave patterns
altered. Choice of location can reduce
sedimentation in shipping channels - Tidal barrage highly modified sediment regime
and nutrient flux upstream and downstream.
Navigation impacts
19also.......
- implications for flood risk management
- visual impacts
- socio-economic impacts
20Severn barrage proposal
21La Rance tidal barrage, Brittany
22Annapolis Royal tidal barrage, Canada
23Bay of Fundy, Canada
24Bay of Fundy Annapolis Royal Tidal generator
- Fish passage studies using tagged fish have shown
a mortality rate of 10-70 - Slow but steady shoreline erosion downstream
- Modelling for bigger barrage suggested that
backed-up tide would have caused sea level in
Boston to rise by six inches
25Severn barrage proposal
26The view of the statutory agencies
- The Severn Estuary is an internationally
important habitat with unique ecology - Nature and scale of barrage proposals would cause
irreversible impacts to features, species and
habitats of international importance - Direct impact on Severn Estuary Special
Protection Area (SPA), proposed Special Area of
Conservation (pSAC), and the rivers Wye and Usk
SACs - A Severn Barrage development would not be
possible within the current legal framework
provided by the EU Habitats and Birds Directives - Cannot envisage how required compensatory habitat
could be provided to replace those that would be
lost - The case for a barrage is being promoted without
proper consideration of other, potentially less
environmentally damaging options - Water quality would be affected as a direct
result of the barrage (through the) modification
of the sediment regime (and) nutrient flux -
English Nature, Countryside Council for Wales,
Environment Agency 2006
27The view of the statutory agencies (2)
- Barrage would fundamentally alter the basis for
determining appropriate limits for discharges to
and abstractions from the estuary and the rivers
that feed into it - Existing defences and new strategies in
preparation will manage the flooding impacts of
climate change without a barrage - May be a downstream increase in vulnerability to
tidal and storm surge flooding and consequent
erosion caused by reflected tidal waves at the
barrage face - Major environmental impacts due to the vast
amounts of materials required - Substantial ancillary and infrastructure
development including the need to modify or build
new port facilities - Difficult to envisage how the proposal would fit
with the requirements of the Water Framework
Directive, e.g. requirement to aim to meet good
status by 2015 - A major programme of predictive environmental
studies will be needed, (taking) several years to
complete -
English Nature, Countryside Council
for Wales, Environment Agency 2006
28Infrastructure development
- Severn barrage is only partly about energy
generation - Will urbanise, industrialise and commercialise
the land around the estuary - New roads and airports, marinas, housing
developments and business parks may stimulate
job-creation, inward investment and increased
land values - BUT will increase dramatically the ecological
footprint of south east Wales and SW England - Will add significantly to our CO2 emissions,
since unlikely that it can be achieved in a
carbon-neutral way - Lets have a public debate about economic growth!
29Increasing supply or reducing demand ?
- Will projects like the barrage be seen as big
hits to fill the energy gap? - Associated infrastructure will then claim to be
"supplied" by green energy rather than reducing
CO2 emissions overall - Will it suck in investment that should go to new
technologies? - Will it make efficiency measures and
decentralised supply less likely?
30Millennium Ecosystem Assessment 2005
- Mapped out the engineered future represented by
the barrage along with a number of other possible
scenarios - Many ecosystem services have been degraded by
actions taken to increase the supply of other
services, such as energy - Trade-offs often shift the costs of degradation
from one group of people to another, or defer
costs to future generations - Benefits reaped from our engineering of the
planet have been achieved by running down natural
capital assets - The overall efficiency of our economy increases,
but it is shadowed by the risks inherent in
large-scale human-made solutions and rigid
control of ecosystems - Technology sometimes creates new problems and
vulnerabilities problems seem to emerge faster
than solutions - Costs of managing the environment are continually
rising, and environmental breakdowns that affect
large numbers of people become more common
31Sustainable Development Commission Review
- Timing
- October 2006 recruit assistant and begin scoping
- October/November prepare tender material and
send to invited list - November let contracts
- January/February 2007 research completed,
publish immediately(?) - March-June publish SDC report
- Scope of research
- UK tidal resource assessment resource mapping,
electricity contribution, grid constraints - Technology assessment advantages and
disadvantages, economics, embedded emissions - Case study 1 - Severn Barrage proposals
- Case study 2 - Severn non-barrage proposals
- Case studies 3-4 tidal flow and small-scale
barrage options around the UK - Outputs
- evidence-based reports by consultants
(fact-based, no recommendations) - SDC-produced report on tidal power with
recommendations - SDC-produced booklet summarising the report
32Sustainable Development Commissionoliver.knight_at_
sd-commission.org.uk mailtotidal_power_uk-subsc
ribe_at_yahoogroups.co.ukwww.sd-commission.org.uk
33In conclusion
- Welcome this conference, improving the
information flow between scientists, politicians
and local authorities - Climate change an urgent economic, social and
environmental imperative - WWF believes energy efficiency should be tackled
first - Smaller scale modular renewable technologies next
- Support the review of marine renewable energy
being carried out by SDC - Renewable energy should be looked at in the wider
context of sustainable development
34www.wwf.org.uk"Turning the Tide"www.wwf.org.uk
/cymru