Solar electric generation produces no pollution or emissions. The energy required to manufacture a solar panel is recovered in just 3-4 years of operation and the panels themselves will last 40-50 years. Solar electricity reduces the effects of coal burning power plants such as mercury in our water and carbon dioxide in our air.
Off-grid systems are not connected to utility power. This means that you produce all of your required power on-site. Since solar panels only produce power when the sun is shining, power must be stored in batteries for use when the sun is not present. Off-grid systems provide energy independence and are often cost-effective for remote locations with no existing utility service. For a more detailed system diagram see the Off-Grid System Diagram.
Grid-tied systems are still connected to utility power. Instead of storing excess power in batteries, a grid-tied system sells it back to the utility. These battery-free systems are lower maintenance and lower cost than an off-grid system. Since the utility is still present, grid-tied systems need not provide all of the electrical needs of the building; the system can start small and be easily grown over time. For a more detailed system diagram see the Grid-Tied System Diagram.