(a) Solar cells: Solar cells are called photovoltaic devices, which are made up of silicon, that converts sunlight directly into electricity. Solar cells produce electricity, without polluting the environment. No harmful gases, no burning and no wastes are produced.
It can be used for street lighting, traffic signals, water pumping and battery charging system, etc.
It is used in artificial satellites and space probes.
It provides radio and TV transmission to remote areas.
It is used in calculators, electronic toys and watches.
(b) Solar panel: Arrangement of many solar cells side by side connected to each other is called solar panel. The capacity to provide electric current is much increased in the solar panel, but the process of manufacture is very expensive.
(c) Solar cooker: Solar cooker consists of an insulated metal box or wooden box, which is painted from inside, so as to absorb maximum solar radiations. A thick glass sheet forms the cover over the box. The reflector is the piano mirror, which is attached to the box. The food is cooked by energy radiated by the Sun.
(d) Solar thermal power plant: In solar thermal power plants, many solar panels are used to concentrate sun rays, to heat up water into steam. The steam is used to run the turbines to produce electricity. The solar energy is available in our country at free of cost, do not cause any pollution and is a renewable source of energy.
