Collect information about solar, wind, tidal and water power and prepare a scrap book.
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Collect information about conventional energy sources from internet and prepare a note on it.

Explanation

Solar energy :
1) To use solar energy is to generate electricity from sunlight. For this purpose special chemical substances which are sensitive to light have been developed.
2) When light falls on these substances, small chemical current is generated. This material is coated on a metal plate and this is used for producing large amounts of electricity. This current can be stored and used when needed.
3) Watches, calculators, street lamps have been invented which use the current produced by light falling on light sensitive material.
Wind energy : Wind mills are in use for centuries especially for pumping water from wells.
1) In wind mills, wind rotates the blades of wind will and is used to move the pistons and lift the water from the well.
2) In earlier days, the fan blades of wind mill were made of wood or thin metal sheets which heavy and inefficient.
3) In recent years, wind mills are made of tough, strong, light weight plastic material and wind energy is being used to pump water and to run turbines for the production of electricity.
Tidal energy :
1) Large amounts of energy (kinetic energy) is stored in the waves especially in seas.
2) Special devices have been made to rotate as the water passes through them by the wave action.
3) This is used to run turbines or generate electricity.
Water power :
1) Dams are constructed across the rivers. Water from the reservoir falls from a height on the turbines.
2) This wter falls is used to derive turbines to generate electricity. These are called hydro electric projects.