Types Of PV systems

The Hybrid System: this system uses PV for a majority of their electric generation, but, when needed, backup generators, such as an internal combustion engine supplies extra power in periods of low (or no) sun conditions. The engine can be run on bio-diesel, diesel gasoline, or propane, depending on the configuration of the machine. Generators will produce AC power that a battery charger (either stand alone or incorporated into an inverter) will change to DC. The internal combustion engines can definitely be loud and stinky, but to mitigate that situation, in periods of an abundance of sunlight, the array can be used to charge the battery. The Grid System: This system uses PV for a portion of the electric generation, but remains hooked up to the local electric utility lines for back up electricity. Some systems don't have any battery backup, but routes any excess electricity to the utility grid for use for other customers. This offsets their bill, getting credit to use in periods of low sun, or may even turn the electricity meter backwards! Off-Grid PV System: There is no hook-up to the electricity grid at all. This system requires knowledge of how the basic functions and elements of their systems work. This is an example of a off-grid PV system design guidelines: https://goo.gl/YZyTC4 Among the components needed are: a backup generator for periods of low sun, (some true greens avoid this because it is noisy and polluting), and an inverter which converts DC to AC energy, some rewiring of the house, and a whole lot of commitment to this particular project!