Residential Solar Panels – Multiple Factors to unprotected to Success
People who to peek briefly at a roof with solar panels in place don’t realize the multiple factors behind their design and placement. Incorrectly calculating one component of a solar strength system can dramatically reduce the equipment’s strength-generating capacity.
One of the most important factors to consider before roof or pole-mounting photovoltaic cells is the degree of shading present. Individual cells are arranged in arrays or series on single photovoltaic or “PV” panels. Shade falling on just one cell can shut down the whole series, including cells that are in complete sun, and can create a current drain throughout the system.
The degree of light the panels will receive is also a major concern. Latitude and cloudiness are the greatest factors in calculating luminosity. Two identical strength arrays installed at the same latitude, for example one in Seattle and another in Spokane, WA, will provide radically different amounts of electricity. The panel in Spokane, which receives semi-desert levels of sun will outperform the panel in perpetually cloudy Seattle.
The panels should be tilted at approximately the same angle as the site’s latitude and, in the northern hemisphere, they cannot confront more than 15 degrees off due south. Optimal tilt during the summer months would be 15 degrees less than the area’s latitude, and in winter 15 degrees more. Many residential roofs have neither the angle nor the correct arrangement to capture the best sun in all seasons.
The systems that return the best performance are pole mounted and actively track the sun. Computer-controlled motors move the PV panels. The goal is to keep the surface precisely perpendicular to the sun, consequently maximizing light capture and energy production. Tracking technology will increase energy production in a given system by 25% over stationary units.
Magnetic declination is also a factor, a detail of which most solar strength neophytes are completely unaware. To unprotected to the proper angle for the panels, the difference between the magnetic poles of south and truth south must be additional or subtracted. Minneapolis, for example, has an almost zero adjustment for declination, while Seattle’s is approximately 19 degrees. Declination maps must be consulted for correct arrangement of the range.
Finally, the relative performance of PV panels will vary by manufacturer and form. It’s best to read independent reviews in addition to consulting the product specification sheets to make a good evaluation. The highest performing residential solar strength systems will likely be so expensive that complete amortization in net electricity savings will be impossible. With good choices and a careful consideration of all applicable factors, however, substantial electrical savings are possible, which is why residential solar strength generation continues to grow in popularity.