LETTERSFrom Roger Bunney, Romsey:
THECounty Press letters debate continues almost weekly on the pros and cons for wind powered generators.
Forgetting the visual impact of these high-rise generators, the one problem that cannot be solved is that the wind isn’t of constant strength all the time which, in turn, means the blades are motionless for periods — no power output — the turbines can therefore only be used as a 'top-up’ in conjunction with other forms of energy production.
But what is constant, day after day, season after season and surrounds the IW is sea water — which is tidal — it moves. Just go down to Fort Victoria and look across to Hurst Castle and then at the sea water flow. There’s much energy in that water flow.
Alderney is the most northerly Channel Island, perhaps eight or so miles from the French coast with a population of about 2,400.
Alderney Renewable Energy (ARE) has just signed agreements in Paris to work in conjunction with Open Hydro, an Irish turbine manufacturer, and with the large naval ship builder DCNS to proceed with development of tidal turbines in the tidal race seabeds that surround Alderney.
The first of four 16m-diameter tidal turbines has just been installed at Paimpol, Brittany, and at an average tidal velocity of four knots is producing a peak output at 850KW, a similar turbine in the waters off Alderney at 8 knots could produce up to 2.2MW of electricity.
Once the tidal turbine system is fully operational the Alderney authorities reckon they’ll export electricity to the French mainland and possibly the UK, bringing back £11 million in royalties.
Along with the plans for the large seabed turbines in the Alderney main Tidal Development Area, another project is advancing — that of the Tidal Pumped Storage System — which will be based at Fort Albert.
Here, three 4MW sea turbines will be installed, harnessing tidal power, but surplus power will be used to pump up seawater to a land-based reservoir, which at slack tide/non-tidal movement the water will be released through traditional hydro turbines to produce a continuity supply of electricity during tidal lulls.
If tidal power can be harnessed from, say, the Hurst-Yarmouth channel then the power output potential would appear to be high, available continuously, silent running and the on-shore infrastructure having minimal visual impact compared to say many wind turbines on high ground and downs around the IW.
Perhaps its worth thinking about?