PV panels are the starting point of any PV system. Here, sunlight is converted into electricity. The following components comprise a typical PV panel:

• Squares of photovoltaic material
• A strong backing material (usually a plastic)
• A tempered glass front
• A metal frame

Photovoltaic materials have the ability to generate electricity when exposed to light. The most common photovoltaic material used in PV panels today is silicon, the same material found in computer chips and electronic devices. Chemicals are added to the silicon to enhance its ability to generate electricity when exposed to sunlight.

The silicon is formed into thin squares that are attached together by small wires to form an assembly of squares. This assembly of squares is sandwiched between the backing material and glass, then surrounded by a metal frame, to create a PV panel. The backing material and tempered glass serve to protect the photovoltaic material from the elements. Today's PV panels are much stronger than home windows, and have survived hurricane-force winds.

Maryland's house uses 34 Sanyo HIT-205BA3 panels, each generating 205 watts of electricity. Doing a little math on a sunny day, our array is capable of generating 6,970 watts of electricity.