Page 304 - Electrician - TT (Volume 2)

ELECTRICIAN - CITS

Fig 1

Tidal power generation

Objectives: At the end of this lesson you shall be able to:
• explain the features of tidal power generation
• state the system on which the tidal power generation works
• state the advantages and disadvantages of tidal power generation.

The generation of electricity using tidal power is termed as tidal power generation. It is basically the transformation
of tidal power found in tidal motion of water in seas and oceans into electrical energy.
Tidal power

Tidal power is the power inherent in tides at sea or oceans, that is power of motion of water actuated by tides.
Tides are defined as the increase and decrease in water levels due to the motion of water from one place to the
other. Thus there is a renewable source of energy in the tidal motion of water at seas and oceans. This source of
energy could be used to generate other types of energy that could be useful in industrial applications.
This is done using a very basic idea involving the use of a barrage or small dam built at the entrance of a bay
where tides are known to reach very high levels of variation. This barrage will trap tidal water behind it creating a
difference in water level, which will in turn create potential energy.
This potential energy will then be used in creating kinetic energy as doors in the barrage are opened and the
water rush from the high level to the lower level. This kinetic energy will be converted into rotational kinetic energy
that will rotate turbines giving electrical energy. Fig 1 shows the process in very simple terms.

Fig 1

Working of tidal power generation system
In very simple terms a barrage is built at the entrance of a gulf and the water levels vary on both sides of the small
dam. Passages are made inside the dam and water flows through these passage and turbines rotate due to this
flow of water under head of water. Thus, electricity is created using the turbines. A general diagram of the system
is in Fig 2.

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CITS : Power - Electrician & Wireman - Lesson 106-116