In very basic terms, a solar panel (PV module) is a device that will produce a flow of electricity under sunlight. This electricity can be used to charge batteries and, with the aid of an inverter, it can power normal household electrical devices, or "loads". PV modules can also be used in systems without batteries.
Most solar panels (properly called "modules") are framed in aluminum, topped with tempered glass, and sealed by a waterproof backing. Sandwiched between the glass and backing layers are the photo-reactive cells themselves, often made of silicon. On the back of the module is a junction box that may or may not have two cables coming out of it. If the junction box has no cables, it can be opened to access the electrical terminals where wires can be attached to conduct the generated electricity away from the module. If there are cables already in place, the junction box is usually sealed and not user-accessible |