| The sun has long been a source of both light and heat | | | | Solar cells are devices that use photovoltaic |
| energy. The heat energy can be used to heat air and | | | | technology which convert light energy directly into |
| water, and the light source is employed to generate | | | | electrical energy. These power systems were initially |
| electricity. Of course, the greatest benefit of solar | | | | developed for use in space, where they could make |
| energy is that it is a totally free energy source, so the | | | | use of a free source of available energy. They still |
| only concern is how to collect and harness it for | | | | power most all of the satellites circling the Earth |
| utilization. | | | | because they have an unbelievable life span and |
| A solar collector is a unit that traps the heat energy of | | | | require no maintenance. |
| the sun. It consists of a large, flat glass covered box | | | | Photovoltaic power systems burn no fuel at all and |
| that contains a dark metal plate. The plate absorbs the | | | | have no moving parts whatsoever, so they are clean |
| heat, while the glass keeps the heat from escaping. Air | | | | and silent. This is particularly vital where the main |
| or water flowing through a series of tubes at the | | | | alternatives for creating power and light in remote |
| bottom of the box is warmed by the heat. Solar | | | | areas are diesel generators and kerosene lanterns. |
| collectors can be used to heat homes, provide hot | | | | Needless to say, these types of energy systems are |
| water and air conditioning, and even turn salt water into | | | | very favorable. |
| fresh drinking water via a desalination process. | | | | |