Monday, January 11, 2010
A practical example of the use of solar energy could be seen in some villages of Pakistan where each house has been provided with a solar panel that’s sufficient to run an electric fan and two energy saving bulbs. Prior to this arrangement, the whole village used to be plunged in pitch dark during night. One such example is the village with the name of Narian Khorian, some 50 kilometers away from Islamabad, where 100 solar panels have been installed by a local firm, free of cost, to promote the use of solar energy among the masses. Through these panels, the residents of 100 households are enjoying light and fan facilities. Had these panels not been installed, the people living in this area wouldn’t have even dreamt of getting this facility for decades as the provision of electricity from the national grid was a far cry due to the difficult terrain and high expenses involved.
A layman would normally be interested in knowing as to how electricity could be produced using energy from the sun. Simply put, it can be said that the basic item required to generate this electricity is a solar cell, approximately 2 inches x 1/2 inch in dimension. These cells may be available in other dimensions as well. Some 80 to 100 or even more such cells are pasted on a tampered glass sheet whose dimensions are generally 1.5 feet x 4 feet. The glass sheet with cells pasted on it and inter-connected, is called a solar panel. The light from the sun is used to generate electricity through these cells. It may be clarified that it’s the sun’s light and not its heat that produces electricity. The solar cells are called photovoltaics (PV); the word Photo meaning light and voltaics electricity. The life of a solar panel is approximately 20 to 25 years!
To give you an example of the use of solar energy, you must have noticed solar panels installed on poles along with the telephone booths on your left hand side while commuting on the Motorway. Each of these telephones is being powered by this panel. A battery is installed beneath each solar panel to store energy for keeping the telephone in operation during night when there’s no sun light. It’s a stand-alone system, entirely powered by solar energy. During emergency, the commuters make use of these telephones and call for help.
To give you another example, if you happen to drive from Rawalpindi (Faizabad) towards Murree on the newly constructed Murree Road, you would see on your right hand side blinking red hazard lights installed at the top of each WAPDA pole. Each of these lights is being powered by a stand-alone solar system i.e. a solar panel and a battery. Just imagine, how much expensive and full of hassle it would have been if solar panels weren’t used for this purpose and these lights were provided normal electric connections!