Following is a list of the most frequently asked questions on solar energy:
Q What's the difference between solar photovoltaic (PV) and solar thermal?
A PV is the technical term for converting sunlight directly into DC electricity. Typically people refer to PV as solar electricity. This is not to be confused with solar thermal which is a separate and distinct technology which turns the sun's energy into heat energy. This is most commonly used as a hot-water-based system to supplement your home or business hot water heating needs.
Q How much maintenance is required for solar systems?
A Very little maintenance is required for solar PV. Occasional visual checks and monitoring the output of the system are typically all that is required. Solar thermal also requires little maintenance; visual checks every couple of years and checking the fluid in the closed loop heat exchanger triannually.
Q Do I need a new roof to have solar panels installed?
A If you are concerned about roof replacement in the next five to 10 years, you should consider having a new roof installed prior to installation. Two things to consider; the roof under the panels can last twice as long because the sun, which degrades your roof, is hitting the panels, not the roof surface, and you only need to reroof the southern roof where the panels are to be placed.
Q How long does a typical PV system last?
A Most professionally-installed systems will last 30 to 40 years. Most solar modules are warrantied to last 25 years at 80 percent of their original power production.
Q How long does a typical Thermal system last?
A Most professionally installed systems will last 30 years or more. Most solar thermal collectors are warranted to last 10 years at nearly 100 percent of their original production.
Q Does solar energy work on cloudy days?
A On partly cloudy days PV can generate up to 80 percent of their potential energy production. Solar thermal will still work at close to 100 percent on partly cloudy days.
Q Where is the best place on my property to put solar?
A Your roof is the best place since it is high and typically has more unobstructed sun exposure. However, ground mounts and pole-mounted units work very well if roof space is not available, but the expense is a little more due to longer wire runs and more construction cost of the mounting assembly.
Q What happens if I produce more electricity than I can use on a given day?
A In grid-tied systems, any excess electricity automatically flows back to the electrical grid and is credited to you.
Q How long does the installation take?
A Installing a solar PV system can take anywhere from two to five days, depending on its size. Installing a solar thermal system typically takes two to three days.
*Supplied by the Mid-Atlantic Solar Energy Industries Association