Tidal power is from the tidal action of the sea. As the sea flows towards the land and up an estuary more and more pressure builds up. If a barrage / dam is built across the estuary electrical power can be produced. The advantage of this type of ‘water power’ is that electrical power can be produced as the sea flows in and when the tide goes out..

There is much interest in the use of tidal energy especially the development of large scale tidal power schemes. The power is obtained through the flow of water when filling and emptying partially closed sea basins. A proposed scheme exists for the Bristol Channel (UK). As the tide runs into the 'low' basin it drives turbines and as the tide retreats, again turbines are turned - producing large amounts of electricity. Unfortunately this scheme has been 'shelved' due to cost and possible damage to the local ecology.

QUESTIONS:
1. How do you think building a massive tidal power station would affect the environment ?
2. Do you think tidal power projects such as the one shown above are a good idea ?