Electricity From Solar Energy
Photovoltaic panels are used to convert solar energy directly into DC electricity. Currently they are the most common device we have for this purpose. The electricity, once created, can be used immediately or stored in a battery for future use.
The materials involved with photovoltaic technology were developed in recent times. Under the influence of solar energy, these materials will release electrons. This in turn creates a voltage potential and a flow of electricity. All of these reactions take place on the atomic level without moving parts, and so a photovoltaic panel is also called a direct energy conversion device.
Historically photovoltaic panels were limited to space age technologies. They are used in satellites and the space stations where they reliably and continuously convert solar energy. As an added bonus, the Sun’s radiation is at least 50% more powerful once we break into Outer Space.
In more modern times, photovoltaics are used in residential homes and locations far away from the Electrical Grid. The reason is that the cost of running power transmission cables can quickly exceed the cost of installing a photovoltaic power array. If you are greater than mile from the Electrical Grid, then it is probably a good idea to investigate solar energy. The greater this distance, then the easier it becomes to make that decision.
Solar energy is comprised of two basic types of radiation. The first is beam radiation, which is the direct rays of the Sun we feel on a clear sunny day. On these clear days beam radiation will contribute the majority fraction of the total solar energy and is quite strong.
The second type is diffuse radiation, which is scattered in all directions. A good example is the radiation we experience on a cloudy day, which won’t exactly blind us and isn’t very strong. On a cloudy day, then, diffuse radiation contributes the majority fraction of the total solar energy.
In order to use photovoltaics wisely, one should be in an area abundant with solar energy. Deserts are obvious candidates, in addition to semi-arid and tropical climates. Northern and coastal climates are tougher decisions due to extensive cloud cover, fog patterns, and rains in the winter. Each case should be considered respectively, however, as not all coastal climates are the same.
Photovoltaic panels come in a variety of sizes, voltages, and constructions. They can be wired in series or parallel to meet your system’s needs. 12 volt and 24 volt configurations are common, while 48 volts and greater are used for heavy duty installations. Most photovoltaics in production are about 12% efficient. This may not seem like much, but keep in mind that the cost of solar energy is zero, and they will have typical service lives of 25 years.
One downfall of photovoltaic panels is that they can involve significant up front investment. This is due, in part, to the high purity silicone materials used in their construction. New types of panels are under development, however, and the price of photovoltaics is expected to drop in years to come.
Because of this upfront cost, converting solar energy with photovoltaics can be a tricky decision. In some cases the decision is easy, as with remote properties or emergency reserve capacity. In most cases, however, one should investigate their solar energy patterns, system cost, and local rates of the Utility. One can then make an informed decision based on the number of years involved to realize the savings. Either way, photovoltaic energy is an interesting and self sustaining technology well worth consideration. One can never go wrong when pursuing their energy independence.