Direct Power 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 way photovoltaic panels do this could be the subject of an entire course. They take advantage of special semi-conductor materials that release electrons when bombarded with solar energy. This phenomenon is called the photoelectric effect and occurs at the atomic level.
Photovoltaics were originally developed as part of the space industry. The long life of the panels combined with no moving parts made them ideal for space bound equipment. Solar energy is much stronger outside the Earth’s atmosphere which also helps.
In recent times photovoltaic panels have been converting solar energy for residential homes in far away places. The cost of a photovoltaic array will often offset the costs of routing power transmission cables from the Electrical Grid. When this distance exceeds 1 mile, then the prospects of converting solar energy with photovoltaics makes more and more sense.
There are two types of radiation that are important and contribute to solar energy. The first is beam radiation, which are the direct rays of the Sun. Beam radiation is the strong warm rays we feel on a clear sunny day.
The second type of radiation is diffuse radiation. Diffuse radiation is scattered radiation, and is what we experience on a fully cloudy day. Diffuse radiation is not very strong, but still contributes to the total overall solar energy.
In order to effectively use photovoltaic panels, one should be in a location with a reputation for good solar energy. Beam radiation is the strongest and most desired form. Many states in Western America easily meet this requirement, and additionally some from the South. Coastal and northern climates are not always prime candidates, but should be considered case by case.
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.
Converting solar energy with photovoltaics can be a costly investment. If properly sized and selected, however, this investment will pay itself over time. Anywhere from 5 to 10 years payback is a possibility. New types of panels are under development and may be released into the solar energy market in years to come. Some of these panels are geared to lower cost, while others are geared toward increased efficiency.
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.