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As the power demand is going on increasing day-by-day, it is responsibility of our engineers to make it available as per the demand. Many of the power generating plant are using non-renewable sources as their primary source. But these may become extinct at any time and before facing the situation we have to choose an alternative to avoid the power crisis. One of the best alternatives is choosing non-conventional sources like solar energy, wind Energy, tidal energy, bio-mass energy etc. as the primary sources for power generation in power stations. The power from these sources is several times greater than the one, which we are using at present. Out of these energy sources, the best one which suits for our country is the solar energy. The power from the sun intercepted by the earth is approximately 1.8*1011 MW, which is many thousands of times larger than the present consumption rate on the earth of all commercial energy sources. Thus if we convert this to other forms of energy, it may be one of the most promising of the non-conventional energy resources. As we know that the tropic of cancer passes midway through the earth, our country is one of hottest country in the world after the continent Africa. There are some places in the country where the mercury level raises up to 500oC during summer. So if we use this energy as the primary source for generation, almost every house in our country can have power supply as it will be available at very reasonable cost. As far back as 5,000 years ago, people "worshipped" the sun. We know today, that the sun is our nearest star and without it, life would not exist on our planet. We use the sun's energy every day in many different ways. Indirectly, the sun or other stars are responsible for all our energy. Evennuclear energy comes from a star because the uranium atoms used in nuclear energy were created in the fury of a nova star explosion. Let's look at ways in which we can use the sun's energy which is also called Solar Energy. Solar energy can be converted into other forms of energy, such as heat and electricity. In the 1830s, the British astronomer John Herschel used a solar thermal collector box (a device that absorbs sunlight to collect heat) to cook food during an expedition to Africa. Today, people use the sun energy for lots of things such as to heat a fluid in solar collector panels. Simple types use flat collector panels mounted on a south- facing roof or wall, each with transparent cover to admit sunlight. Water circulates through channels or pipes inside each panel. The inner surface is usually painted black, because black surfaces readily absorb heat. The water is heated, and then the hot water is pumped to a heat exchanger that extracts the heat for use within the house. Solar energy can also be used to generate electricity in photovoltaic (PV) cells. Photovoltaic cells are made of semiconductors, similar to those used to make computer chips. Until recently these cells were very costly to produce.