How does this work?

The word “photovoltaic” literally means electricity from light. Solar photovoltaic (PV) panels are made of silicon, which generates an electrical current when exposed to light. The panels consist of two slender slices of silicon, one with a positive charge (p) and the other with a negative charge (n), sandwiched under a sheet of glass. An electrical field forms at the boundary where the two silicon layers meet, called the p-n boundary.

Sunlight reaches Earth in the form of photons, which have the ability to knock an electron free from a silicon atom. Free electrons have a negative charge and are drawn to silicon atoms that have lost electrons. As the negative free electrons move toward silicon atoms, they are captured by the electrical field that forms at the p-n boundary where the positive and negative silicon layers are joined.

Fine wires on the surface of the silicon capture the free-moving electrons, and when they are connected in a circuit, direct-current (DC) electricity flows from the PV panel. The DC flows to an inverter, which changes 96 percent of the electricity generated by the solar modules to an alternating current (AC), which is the kind that comes into our homes and businesses.

Solar needs no maintenance other than an occasional spraying with a hose in the summer dry periods. In the winter, rain washes away the dust and debris. Solar systems are solid state, meaning they have no moving parts to ever wear out, heat up or buzz. They produce no emissions into the air, ground or water.—T.G.