Back to Basics

A homeowner who has made the decision to use sunlight to power his home has several choices, since no “standard” or “best practice” has been established as yet. Cost, preferred roofing material, aesthetic appeal, and the availability of rebates are often the drivers of choice.

Here are the current options for generating electricity from the sun:

Solar Panels: Seen on rooftops since the 1970’s, the number of panels depends on the desired kW produced. Roof mounted panel sizes vary with the application; the active ingredient is silicon; the housing is metal (usually aluminum); the panels are attached to the roof using metal braces and clips. http://www.youtube.com/watch?v=Dr6UEtngtdU

Thin film solar panels are flexible panels that are glued to the roofing material. They are thinner and lighter, but slightly less efficient, than the standard panels.
http://www.youtube.com/watch?v=YYJe12X6T50

Building Integrated Photo Voltaics (BIPV) are photovoltaic materials that are used to replace conventional building materials in parts of the building envelope such as the roof, skylights, or facades. For a homeowner, there are solar electric roofing tiles ( or shingles ) or cells imbedded in cement tiles. The tiles do not change the profile of the roof and appear almost exactly like the rest of the roof (they do have a slight shine and are dark, so would be more obvious against a light colored tile). Other BIPV options are solar awnings which serve the double functions of generating electricity and providing shade. Check out the website of 4 Times Square, New York City to see an impressive commercial use of BIPV.
http://www.iea-pvps.org/cases/usa_01.htm
--or for a more general presentation: http://www.ornl.gov/sci/solarsummit/presentations/ORNL-Coonen/pdf

Once installed how does the homeowner use the solar generated power?

The system can be tied to the electric grid, so that it is added to the regular source of electricity for the home. Many Utility companies track any electricity produced, give the homeowner a credit against the power bill or mail them a check for the excess.

System tied to the grid but with battery backup to capture excess production for use when sunlight is low.

Off grid, independent solar electricity systems use solar collectors plus a backup generator.

References:
http://www.thesolarguide.com/solar-power-uses/cost-faq.aspx
http://en.wikipedia.org/wiki/Solar_cell