2. The Sun The sun is made up of 70% hydrogen, 28% helium, and 2% other small atoms. The estimated surface temperature of the sun is about 5800 o C.

3. Solar Energy Most of the energy on Earth comes from the sun. Even fossil fuels such as oil and coal are products of the sun’s energy. The sun releases light and heat as pairs of hydrogen atoms constantly fused into single helium atoms. Sun has existed for 5 billions years and its gaseous matter is sufficient to maintain the reaction for another 5 billions years.

4. Sunlight Sunlight is made of tiny particles of light called photons. Photons are speedy, traveling millions of miles from the sun to the Earth in only 8 minutes and 20 seconds!

5. Photovoltaics Light energy from the sun can be converted directly into electricity by using photovoltaics.

6. Photovoltaic Cells Photovoltaic (PV) cells convert sunlight to electricity. Each PV cell produces a small amount of electricity when sunlight hits it. The individual cells can be wired together into a module in order to produce more electricity. PV cells produce the most electricity when the sun is directly above them. PV cells produce less electricity in cloudy days and do not work at all at night.

7. Photovoltaic Applications Electricity from photovoltaic (PV) can be used directly stored in batteries for use latter Fed into utility power lines for use elsewhere PV can be portable used as a generating station away from utility power plants

8. Solar Thermal Energy Solar thermal energy is the use of sunlight to generate heat. Homes can be heated and cooled with solar thermal energy.