Solar basics: The sun is unlimited source of energy. Trillions watts of solar energy is generated due to nuclear fusion of hydrogen atoms. Produced heat by fusion heats the outer surface of the sun. From outer surface also called chromo sphere heat or energy reaches to outer layer of earth’s atmosphere by radiation. Chromo sphere is just like a hot body having temperature more than 5800°K (0°C is 273°K and 100°C is 373°K). Each and every time 1366 watts per meter square (1366w/M^2) energy comes at the outer atmospheric layer of earth. The solar energy is made of tiny waves having size in nm (1 neno meter = 10¯9 Meter). The composition waves or rays are 7% ultraviolet rays (UV), 46% visible rays & 47% infrared. The size of ultraviolet rays are 0 to 280 nm, visible rays are 280 nm to 780 nm & infrared 780 nm and above. Out of energy reached at the outer atmospheric layer of earth, some reflects back to sky, some absorbed by the atmosphere and remaining about 1000 watts/M^2 reaches to earth's surface. The sky is seems blue due to reflection of ultraviolet rays(UV).