Not only will you start immediately seeing lower utility bills, but you’ll also see long-term savings over the lifespan of your system. A grid-tied PV system can protect you from electricity price increases for decades.

Your current monthly energy use and the size of your system will determine your actual savings amount. And with little or no startup costs, systems can start paying for themselves immediately. Savings will vary based on several factors, including system size, performance and your household's average energy usage.

This very much depends on the positioning of your roof, the tilt and the structure. Without racking system every kilowatt of the solar array takes about 60-70 square feet. So a typical 5kW array will take a roof area of about 300-350 square feet.

Net metering is a utility billing mechanism available that offers a credit to residential and business customers who are making excess electricity with their solar panel systems and sending it back to the grid.

When you have a rooftop solar system, it can often generate more electricity than you consume during daylight hours. With net metering, the homeowner is only billed for the "net" energy used each month, that is, the difference between the energy produced by the solar power system and the energy consumed by the house over the monthly billing period. When your house or business is net-metered, you'll see the meter run backwards, and that means, you may get a credit to hedge against the electricity you use from the grid when it's not sunny or at nighttime. You are then billed only for your "net" energy use. The excess energy generated gets put back to the grid for your neighbors to use.