Europe's only tidal power station is at Rance in Northern France. A number of sites in the U.K could be developed to provide tidal power. The drawback is that these schemes affect the habitat of seabirds and fish because they alter the tidal currents. Also, barrage will only provide power for about 10 hours per day. Power for the other 14 hours must be provided by other means.
Waves possess great energy.
Experiments with various different designs of generator have proved that waves can provide electricity. However, there are problems in developing and building wave powered generators which are both cheap and efficient, as they must be strong enough to cope with storms while being light enough to work with small waves. The drawback is that these schemes affect the habitat of birds and fish because they alter the tidal currents. If every reasonable project in the UK were to be exploited for tidal power the yield could be over 50 kwh a year representing 20 per cent of the electricity demand in Britain. It would be a very large project costing over 8000 million.