Solar Energy The Power of the Sun
We depend on the sun for survival. Without the sun’s warmth, the earth would cool to a temperature less than -250°C (-450°F). Without the sun’s light, plants would not be able to produce food through photosynthesis.Technically, a large percentage of the energy we use can be called “solar energy.” Wind is the result of unequal heating of the earth by the sun. Hydropower is dependent upon the evaporation of water. Wood and other forms of biomass capture the sun’s energy through photosynthesis. Even fossil fuels can claim solar energy as their original source, since they are the remains of plants and animals from prehistoric times. The sun’s energy can also be used directly for heating and for generating electricity.
Where does the sun get its energy? The energy results from a thermonuclear reaction that occurs within the sun itself. The sun is a big ball of gas, made up mostly of hydrogen and helium. At the center of the sun, the extremely high pressure and temperature cause hydrogen atoms to break apart. Then, the hydrogen nuclei fuse to form helium atoms. When this nuclear fusion process occurs, solar energy is released.
