Once you have added a solar system to your house, your local utility company will begin to monitor how much power you create. If necessary, your utility company will provide for your excess energy needs, but these should drastically diminish after installation. In some cases, you may find yourself creating more energy than you need. In these cases, the utility company will credit you for the energy created.

1. Sunlight shines down on the Earth in the form of mass-less particles called photons.
2. Tiny silicon wafers in your solar panels pick up these photons, freeing electrons and creating a direct current that flows through the array.
3. An inverter converts the solar panels’ direct current into usable alternating current.

PV systems to power buildings fall into four general categories:

1. Grid-interconnected or grid-tied PV systems are the most popular, and use special inverters to allow electricity to flow safely back into the electric grid.
2. Grid-interconnected with battery back-up systems are connected to the grid, and seamlessly continue powering your home when the grid goes down.
3. Off-grid PV systems are stand-alone systems that are independent from the power grid.
4. Utility-scale PV systems, or solar farms, provide power to regional users through (or in cooperation with) electric utility providers.