Solar panels are made from silicon and other materials. When the photons in sunlight hit solar panels they release electrons to a higher state resulting in electrical current. This current is Direct Current and can be stored in batteries or sent to an inverter that converts it to Alternating Current (AC) which is what a typical house or business uses. This AC electricity is sent into the distribution panel for powering circuits in the home or business. Excess capacity can be sent back into the grid and the power company will consider this a credit. The illustration below is a simple explanation of this process.
The optimal place to mount solar panels in North America is on a directly south facing rooftop that is not in the shade of other buildings or trees. The potential of electrical production of a solar power system is directly related to the direct exposure of the solar panels to the sun from dawn to dusk. Indirect exposure reduces the production capacity of the system.
In a solar power purchase agreement (PPA) or solar lease, a customer pays for the solar power system over a period of years, rather than in an up-front payment. A solar power purchase agreement (PPA) is often a financial agreement where a developer arranges for the design, permitting, financing and installation of a solar energy system on a customer’s property at little to no cost. The developer sells the power generated to the host customer at a fixed rate that is typically lower than the local utility’s retail rate. Depending on location, customers can frequently purchase solar for little or no money down, and often realize energy savings immediately.
Solar panel systems have a long lifespan. Many manufacturers warrant solar panels for 25 years, though they have been known to perform for in excess of 45 years. Inverters typically last for about 15-20 years.