Direct Power From Solar Energy
One of the more significant emerging technologies with solar energy has been photovoltaic (PV) electricity. Photovoltaics use special materials to convert solar energy directly into electricity. This electricity can be used immediately or stored in a bank of DC batteries.
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.
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 we have is called diffuse radiation. As the name implies, this radiation is scattered in all directions. It is the primary source of radiation on a cloudy day, or when one is sitting in the shade. Diffuse radiation is not as powerful, and therefore one should not plan on running a photovoltaic system with diffuse radiation alone.
To utilize photovoltaic panels one should be in a location with a good amount of Sun. There are quite a few States in the Western U.S. that fit this criterion. The more beam radiation a location receives the better, as this can easily double the total amount of solar energy.
Photovoltaic panels can be connected in series or parallel to meet your solar energy needs. 12 volt, 24 volt, and 48 volt DC systems are common. Most PV panels fall in the range of 12 to 14% efficiency, and have lifetime expectancies of well over 20 years.
Ultra high purity silicone semi-conductor materials are involved in the modern construction of photovoltaic panels. Due to this, photovoltaics can be an expensive option for using solar energy. New materials are under development, however, and are aimed at lower the manufacturing cost. Cadmium Telluride based solar panels are one such technology. The price of solar panels is expected to fall in coming years if these new materials proceed.
If you are thinking about installing a photovoltaic system, then a quick analysis of your weather patterns and local Utility rates will help the cause. If considering a remote installation or emergency reserve backup system, then this decision could come easy. Regardless of your choice, photovoltaics are an interesting topic of discussion in the realm of self sustaining solutions pushing us toward energy independence.