PV panels are what we use for the effective recovery of the energy of the sun, and in turn converts this energy into usable electricity.
As you may expect, panels are available in a huge variety of sizes both in terms of wattage ratings, physical size and power output.
Until recently, solar panels use silicon as a basic material to produce electricity almost exclusively. This limitation is a bottleneck preventing been significant breakthroughs in solar technology on the surface.
Let’s discuss this venerable panels first.
The panels are available through amorphous, polycrystalline and monocrystalline silicon. Amorphous panels are made of silicon, which is not just arbitrary crystal silicon. The efficiency of this type of panel is usually about 6%. This means that for every 1000 watts of solar energy that affects a particular panel, 60 watts is converted into usable electricity.
Following the ladder is polycrystalline. What more expensive to produce, but so that a higher efficiency of about 12%, these panels are only half of the physical size of an amorphous panel of similar output. This may be an important factor in your choice of the panel, but there is more than just to consider the size.
A monocrystalline panel is as it sounds, a cut single crystal of silicon. Efficiency of about 14% are the norm with this type, again producing more power with less space.
Here in the Pacific Northwest, we are often exposed to cloudy skies. Of course, this reduces our insolation and we are not able to get as much power as we want to get.
The amorphous panels actually pretty good under these conditions, and on a pure dollar for dollar basis, outperform their more efficient brethren. Undoubtedly, the opposite is true if you lived in Arizona!
Typical net voltage outputs for these panels are 12V, 24V and 48V. Most panels 12V.
The panels are made up of individual cells, each of which carries approximately half volts to the panel. Typically, a panel of 32 cells and 16 volt produce under certain load. The open-circuit voltage will usually be 21 or so. The reason that a 12 volt panel produces 16 volts is this. Most 12 volt battery banks actually hold closer to 14 volts at full load. A panel shall have a higher voltage than the battery bank, or it will have the ability to induce a load miss out on the battery. The mechanics of it all be handled by the controller, but in essence, the panel should simply be able to provide sufficient voltage to the batteries in order to do an effective job.
There is a new kid on the block with completely different technology. A California company is currently producing a new type of printed solar.
A special printing press developed, which uses a proprietary blended ink for printing on a metal roll product. In contrast to the type of silicon cells made and assembled one by one, the printed type has the possibility of flowing out large rolls of printed material at high speed. Running at 100 feet per minute, the capacity of a single machine is no less than one gigawatt of power per year.
The ink is a blend of copper indium gallium diselenide, known as CIGS.
Production is implemented with all production currently under discussion panel for the commercial market. It seems to me that this is the technology of the future and one in which we will all rejoice.
Source: http://ezinearticles.com/?Solar-Power—Photovoltaic-Panels&id=2518326 by Keith Elliott