Last month, we highlighted SAS’s campaign for a wave hub and farm off the north coast of Cornwall. Consequently, there has been much debate…
The deal is this: yes, we all worried about out future reliance on coal, gas and oil for power. Yes, the majority of us want to see more renewable energy resources being utilized (wind & waves as the main two). But if the proposed wave farm off the coast of Cornwall will affect the quality of the waves that hit the beaches along the north coast – would you still be so keen to support the project? This puts the SAS in a difficult position but after extensive research in co-ordination with Exeter University, they have concluded that it won’t have much affect on the Cornish surf.
Point 1: We must utilise wave power
Areas such as the South West peninsular and the West Coast of Scotland have a huge wave energy resource, with mean annual wave powers of around 20 - 40 kW per metre of wave crest just a few miles offshore. If some of this power could be harnessed and converted to electricity, it would represent a clean and safe source of renewable energy. This would help to reduce CO2 emissions and therefore help combat climate change, and avoid further investment in hazardous and polluting technologies such as nuclear power.
Point 2: Impact of the wave hub on surf
SAS ensured that comprehensive modelling was carried out into the possible impacts of the proposed wave hub (12 miles off the coast of North Cornwall) on surfing waves inshore.
They have consulted heavily with experts in all aspects of wave energy, oceanography and nearshore coastal dynamics. From this process, SAS are satisfied that the effect of the proposed wave hub on the surf will be minimal and will not affect its recreational value.
PHOTOS: John Carter
Modelling results (courtesy of Halcrow)
Worst case scenario is a reduction in the height of waves at the coast by a maximum of 13%.
A more likely scenario (considering the devices which are to be installed) is a maximum wave height reduction of up to 5%.
The farm will have a greater effect on shorter period waves than longer period waves (swell).
The effect on wave period is negligible.
The hydrodynamic modelling suggests that the effect on sediment transport will be undetectable against the background variation.
Some types of devices are predicted to have a larger effect on wave height than others.
SAS believe that any slight reduction in wave height (i.e. 5% maximum) will be unnoticeable by surfers. Wave period and bathymetry are also key factors in determining the quality of a surfable wave in addition to wave height. The model suggests that both of these factors (sediment transport in the case of bathymetry) will not be altered to any significant degree.
Given this fact, the overall effect on surf quality under these conditions is predicted to be extremely slight at most and undetectable by surfers.
Point 3: Case-by-case support
Clearly, SAS would be very concerned about any proposed plan that resulted in a significant noticeable reduction in surf quality in its lee or reduced the amenity resource for any other watersport. For this reason, whilst backing the technology, SAS will look at each proposal on a case-by-case basis before deciding whether to support or oppose the plans.
"Surfers voting for this are like turkeys voting for Christmas." - John Baxendale, a chartered physicist and engineer who runs a surf forecasting agency.
There is opposition from parts of the surfing community who fear that it will have an adverse affect on the Cornish surf and ruin the £64 million surfing industry on this stretch of coast line. John continues…”It is fairly obvious to me that any barrage of energy extraction would create a wave shadow because it would remove the energy from the surf. It will not just affect the height, it will also affect the quality of the surf” John suggests the rocky coast of Scotland would be better as it won’t affect the local economy.
PHOTOS: John Carter
Wave Hub notes: If it goes ahead the wave hub will involve 20 sets of machines, with pumps, pistons and turbines about 12 miles out to sea off St.Ives Bay. It will generate electricity for 14,000 homes.
For more information please contact Andy Cummins on SAS’s ISDN campaign line, Tel: 01872 555950 or Mob: 07711 767548.