The main component of a photovoltaic (PV) system is the solar cell. This is the part that actually converts the sun's energy into electricity. It consists of a simple chemical composition (usually suspended in silicon) that when struck by rays of light will produce a small electrical charge. This small electrical charge then combines with charges from others cells that have been connected in series or parallel to create a greater level of either voltage or current. The resulting assembly of cells is known as a module. Several modules can then be placed in series or parallel to produce even greater levels of voltage or current to meet the criteria of the system's owner.

The type of electricity produced by the PV system is direct current (DC). The type of electricity we use from the utility company in our homes is alternating current (AC). Therefore, the DC power must first be converted to AC power, by means of an inverter, before it can be used by the system owner or sold to the utility. The inverter will also synchronize the power's wave form and frequency to match the characteristics of the utility's power so all appliances in the home run properly and the utility can provide the excess power to other customers.

Though this is a simple, basic explanation of how a solar-electric system works, there are actually several variables that affect maximum power production as well as some safety precautions to be considered. A good, experienced PV system designer will evaluate your installation site and carefully design the right combination of modules, inverter, mounting rack, and wiring plan to achieve optimum power production, pleasing aesthetics, and the highest safety standards.

To view a short, one-minute video from the U.S, Department of Energy on how a PV cell works, click here.

An informative website from the U.S. DOE on the basics of PV can be found here.

To download and print a pamphlet from the National Renewable Energy Laboratory on PV basics, click here.