The line of solar panels you see on rooftops and that provides solar power for homes is called a photovoltaic solar array. Photovoltaic cells are used to capture energy from light. 
A solar photovoltaic cell is used specifically to capture sunlight. The ones on the roofs of houses are used to provide solar power to homes in conjunction with solar electric generators for residential use.
The solar panels are usually installed on racks fixed to the roof. If you are using this type of system to provide solar power to your home in the northern hemisphere, you will want the array pointed to the true south at approximately the angle of your latitude. In the southern hemisphere, you will want your array pointed true north.
Much of the radiation from the sun does not reach the earth. The average peak density of sunlight, upon reaching the surface of the earth, is around 1,000 watts per square meter. This would be on a clear day, at noon. Therefore, when contemplating the purchase of photovoltaic panels to provide solar power for homes, you want to determine their their efficiency.
Residential panels, providing solar power for homes, generally have an efficiency up to 20%. Their peak output, at noon on a sunny day, would be between 60 and 200 watts per square meter (6 and 19 watts for each square foot).
You can add reflective devices like mirrors to increase the solar power for homes by concentrating sunlight, but this is usually only done in commercial applications.
The Direct Current voltage from the photovoltaic array must be converted to Alternating Current voltage by the use of a DC to AC inverter.
When the system is wired to provide solar power for homes, it will have to meet all national and local electrical codes. At the point where the cables from the photovoltaic array are connected to the house, a DC disconnect switch should be installed. There should also be a dedicated circuit breaker for each set of modules that are connected in series. This is to avoid any reverse current damage from parallel strings.
Next, you may need a battery bank to store solar power for your home. A battery bank can ensure the collection of energy for use on rainy days or at night. The battery bank is connected to your array by a charge controller. Between your battery bank and your inverter, you will need another DC disconnect switch installed. Battery banks are important for people using their array to provide solar power for their homes on a full time basis or for emergency use. If you are only using solar power to save on your total energy bill rather than to get off the grid, a battery bank is not necessary.
If your array is providing solar power on the grid, it will use special inverters. These inverters don’t just supply solar power to homes, but they direct any excess energy from your array to the grid and help you reduce energy cost.
Through these different systems, solar power can work well for your home whether you are on the grid or off the grid.
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