| It is no secret that the sun can be harnessed | | | | burning wood and coals were burdensome. It's |
| to provide a source of energy for homes and | | | | popularity diminished with the discovery of |
| businesses. | | | | an abundance of natural gas and oil deposits. |
| | | | Now they are making a comeback to replace the |
| The sun is a powerful star. It supplies us | | | | depleting fossil fuels that had taken its |
| with energy, through a process called nuclear | | | | place. |
| fusion, and sustains life on our planet | | | | |
| Earth. Solar energy, or energy from the sun, | | | | Solar energy can be in the form of heat |
| has existed since prehistoric times when men | | | | energy or light energy. The technology of |
| would magnify the sun's energy in efforts to | | | | photovoltaic, or PV as it is commonly called, |
| start fires. | | | | converts the suns energy into electric |
| | | | currents through the use of solar cells. |
| The sun is a valuable resource that radiates | | | | These electric currents can be used |
| enough energy on the United States in one day | | | | instantaneously or stored for later use. The |
| to meet the nation's needs for one and a half | | | | PV cells consist of pieces of silicon under a |
| years. Since it is a free, clean and | | | | thin piece of glass. They have both a |
| renewable source of energy, it is an energy | | | | positive and negative charge. Simple examples |
| source that will play a vital role in our | | | | of this are the solar powered calculators |
| future. | | | | that are common today. More complex examples |
| | | | are solar panels placed on roofs. This |
| Using the sun's energy for our energy source | | | | consists of using thin film solar cells as |
| seems like an easy solution to having an | | | | rooftop shingles, roof tiles, and even |
| energy supply forever. Harnessing the suns | | | | glazing for skylights. Unfortunately, the |
| energy is where the problem lies. The sun's | | | | cells generate only about one sixth of the |
| rays shine all over the world and not in just | | | | sun's energy into electricity. This means |
| one spot. Although it takes only 8 minutes | | | | bigger arrays are needed and along with this |
| for sunlight to travel to the earth, trying | | | | come larger costs. |
| to catch the rays over such a wide area can | | | | |
| prove to be tricky. Also, the energy in any | | | | Solar thermal power plants use the sun to |
| one given place will vary due to factors, | | | | heat fluid, which in turn, is transferred |
| such as, clouds and weather conditions. | | | | into steam similar to fossil fuel burning |
| | | | plants. The steam is transformed into |
| The history of using solar energy began in | | | | mechanical energy in a turbine and electrical |
| 1890's when solar water heaters were used in | | | | energy from a generator. The downfall is |
| the United States. Solar water heating | | | | solar plants cannot produce energy on cloudy |
| requires a storage collector and a storage | | | | days. |
| tank. Flat plate solar collectors are mounted | | | | |
| on rooftops. Pipes carrying water are pumped | | | | It is expected the next few years will see |
| through these collectors. The tubes are | | | | millions of households using solar energy. As |
| painted black so they will get hot quicker. | | | | research continues and processes improve, |
| As the heat is collected the fluid in the | | | | using our sun as a renewable energy source |
| tubes get heated. A storage tank holds the | | | | will produce efficiency and cost savings. So, |
| hot liquid. This helps with central heating | | | | let the sun shine in and take full advantage |
| and cutting fuel costs. Solar heaters became | | | | of this warm energy source where you live. |
| popular when natural gas was expensive and | | | | |