Benefits of Photovoltaic Modules

Photovoltaic modules are the devices that have made reliable power beyond the power lines possible. Solar photovoltaic is one of the most widely used alternative energy sources. Even those lucky enough to have a viable hydro or wind site often choose to have a few Photovoltaic modules for back-up or seasonal use. A Photovoltaic module produces electrical current when it is exposed to sunlight. The technology is closely related to and was a spinoff or 1950s transistor technology. Photovoltaics provide clean, uncomplicated power whenever and wherever the sun shines on them, so, not surprisingly; space applications funded most of the early research and development.

Photovoltaic modules last a long, long time. How long we honestly do not yet know, as the oldest terrestrial modules are barely 30 years old. Ask us again in 30 more years and we will have a better answer. All full-size modules carry 10- to 20-year warranties, reflecting their manufacturers’ faith in the durability of these products. Photovoltaic technology is closely related to transistor technology. Based on our experience with transistors, which just fade away after twenty years of constant use, most manufacturers have been confidently predicting 20-year or longer lifespans. However, keep in mind that PV modules are only seeing six to eight hours of active use per day, so we may find that lifespans of 60 to 80 years are normal. Cells that were put into the truly nasty environment of space in the early 1960s are still functioning perfectly.

Modules will catch the maximum sunlight, and therefore have the maximum output, when they are oriented perpendicular (at right angles) to the sun. This means that tracking the sun across the sky from east to west will give you more power output. Tracking mounts are expensive. Due to economies of scale, they‘re usually only worthwhile on larger Photovoltaic systems, generally ones with eight or more modules. All systems are most productive if the modules are perpendicular (within five degrees) to the sun at noon, the most productive time of the day. In the winter, modules should be at the angle of your latitude plus 23 degrees, which is the recessional, angle of the sun. In the summer, your latitude minus the same 23- degree angle is ideal. (On a practical level, many residential systems will have power to burn in the summer, and seasonal adjustment may be unnecessary.) As noted above, modules should have some air space behind them to promote air flow and better cooling.

Generally speaking, photovoltaic arrays that consist of eight or more modules are better off on a tracking mount, and smaller arrays are usually better placed on fixed mounts. This rule of thumb is far from ironclad, however, and there are good reasons to use either kind of mounting.

Benefits

1. No moving parts
2. Ultra-low maintenance
3. Extremely long life
4. Noncorrosive parts
5. Easy installation
6. Modular design
7. Universal application
8. Safe low-voltage output
9. Simple controls

Useful information Solar photovoltaic:
http://www.greenearth4energy.com/solar_photovoltaic.html

Useful information Photovoltaic systems:
http://www.greenearth4energy.com/photovoltaic_systems.html

Useful information alternative energy sources:
http://www.greenearth4energy.com/alternative-energy-sources.html