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Tidal Power

Description

Tidal power harnesses the twice daily variation in the sea level caused mostly by the gravitational effect of the moon and also the sun on the world's oceans.

Tidal Power/ How does it work?

Production of electricity by harnessing the power of ocean tides. Tidal power has become economically feasible as a result of the continuous rise in price of fossil fuels, and a number of nations already possess working tidally driven electric generating facilities. A tidal power plant is similar in principle to hydropower generation facilities in rivers. A barrage (dam) with a powerhouse and turbines is constructed across an estuary or embankment to form a basin (head pond) of sufficient size to allow production of electricity over a reasonable period. For the simplest design, the basin is allowed to fill during flood tide through floodgates and a powerhouse, with turbines spinning freely. Power is produced on ebb tide.

The production of power from Tidal Energy

Step 1: A location has to be found where there is sufficient tidal changes to create enough energy to power the turbines.

Step 2: A dam or barrage is created.
Step 3: Sluice gates on the dam allow the tidal basin to fill on the incoming high tides.
Step 4: The water then exits through the turbine system of the outgoing tide.



Step 5: Turbines are turned by the outgoing water producing energy
Step 6: There are two types of generators that they use at Tidal power stations which transfer the energy into electricity and send it to your home.


Tidal Fence



Advantages

Disadvantages
  • Reduced greenhouse gas emissions by tidal power
    		•
  • Effect on plants and animals which live near tidal stations
  • Easy to predict
    		•
    • Very expensive to construct barrage
  • Improved transportation because of the development of traffic or rail bridges across estuaries
    		•
    • Very little is known about the full effect of tidal power plants on the local environment because so few have been built
  • Not many places have dramatic enough tide change to support a tidal power plant
  • There are times of low power and high power because the tides have high and low periods



    • Other power plants around the world: There is a power plant located at La Rance, Brittany, France and a smaller plant in Annapolis Royal, Nova Scotia, Canada which is a 16 MW plant.

    La Rance

    Bibliography-
    "The Australian Renewable Energy Website"
    Available at: http://acre.murdoch.edu.au/ago/ocean/tidal.html