Wednesday, August 4, 2010

HOW TO PRODUCE ELECTRICITY?

Electricity 

Electricity is a form of energy. It consists of electrons - tiny particles that come from atoms. Each electron carries a tiny electric charge which is an amount of electricity. When you switch on a light, electrons move through the bulb every second. Cables hidden in walls and ceilings carry electricity around houses and factories, providing energy at the flick of a switch. Electricity also provides portable power. Batteries produce electricity from chemicals, and solar cells provide electricity from the energy in sunlight. Lamps, motors and dozens of other machines use electricity as their source of power.

The device used for producing electricity is called a ‘dynamo’ or ‘generator’. The dynamo consists of a huge magnet called field magnet. In between the two poles of the magnet a rectangular coil made of copper wires is made to rotate. The two ends of the coil are connected to two metal rings, which keep on touching two carbon brushes. Wires carrying electric current are connected to these brushes. When the rectangular coil is rotated between the two poles of the magnet, electric current is produced in the coil because of electromagnetic induction. This current is brought to our houses and factories with the help of wires. 

In general two techniques are used to rotate the coil in between the poles of the magnet of a generator. In the first, water is accumulated by building dams across rivers and then it is allowed to fall from large heights over the blades of a turbine by which it starts rotating. The axle of the turbine is connected to the rotation mechanism of the copper coil of the dynamo. The movement of the turbine, thus rotates the coils and electricity is generated. Power-houses producing electricity by this technique are called hydel-power stations. 

In another process coal is burnt to boil water and convert it into steam. The steam so produced is used to rotate the turbine blades which in turn rotate the copper coil in the dynamo, thus producing electricity. Power houses producing electricity by this technique are called ‘thermal-power stations.’ Besides these two famous techniques, atomic energy is also being used to produce electricity. Installations producing electricity by this technique are called ‘atomic power reactors’. In view of the ever increasing demands of electricity, scientists are also constantly engaged in developing new techniques to generate electricity from solar energy and wind power.

No comments:

Post a Comment