Solar Energy Facts

Solar energy is the rays of the sun, or solar radiation, that strike the surface of the earth. This radiation can be converted into other forms of energy including heat and electricity. While on an expedition in Africa in the 1830s, the British astronomer John Herschel used a solar thermal collector box, or oven, to absorb sunlight and produce heat. He used this oven to cook food while in the field.

Today, the uses of solar energy are many. We use solar collectors for heating and cooling homes and larger buildings. Swimming pools are heated with solar energy, Solar energy use falls into three broad groups, passive, active, and photo voltaic uses.

Passive solar systems are used to heat homes by allowing the sun's rays to heat a large thermal mass during the day. This heat storage is then radiated back into the home during the night, warming the house and it's occupants. These systems are largely inert and require no other forms energy to accomplish the task. Passive solar heating occurs naturally all the time with a large paved parking lot a good example. The asphalt collects heat all day long and gives it up long into the night warming the immediate air over the blacktop.

Active solar systems make use of collectors to transfer the energy from the sun to another medium and move the heat to a storage area or other use. Solar hot water heaters are a prime example of an active solar system. A system of tubing is arranged in a collector and filled with a liquid that will transfer the collected heat to the water tank. Either a natural siphon system or an electric pump is used to circulate the liquid through the tubing.

The third major group of solar collectors is the photo voltaic or solar panels. These silicon based semiconductors take the sun's radiation and convert it into electricity. This electricity is then stored in a battery bank and converted to a proper voltage and used to power the appliances and gadgets that we use in our homes.


With all these systems, some form of storage for the energy is required since solar power is only available during the daytime when the sun is shining. The output can be stored or in the case of electricity, transmitted over a power grid to other users.


We use solar power to heat our homes, run our gadgets, heat our swimming pools and make living more comfortable far away from the normal sources of energy. We can help reduce our impact on the earth's resources by making better use of the abundant radiation from the sun.