Off-grid solar electrical systems all use the same basic components, with other elements added according to need. Figure 1 shows a typical off-grid system. Here are the functions of each component:
1. Solar Panel: Converts sunlight into electricity. The power that can be produced by solar panel will depend on the size and number of solar cells and offcourse the light intensity of the sun.
2. Charge controller: The charge controller feeds current into the battery bank at the required voltage. Good charge controllers draw the best performance out of the batteries and are very important for economics because they influence efficiency.
3. Battery bank: The battery bank is typically made up of six or more individual batteries connected with stout cables in either series or parallel arrangements. This component enables the system to be used during night time.
4. Inverter: The inverter changes DC to AC voltages suitable for use with household equipment. An inverter is optional if you use DC loads exclusively.
5. DC loads: You may be using both DC (boat, RV, and auto appliances) and AC loads (standard household appliances). The DC loads are powered by DC (Direct Current eg. 12 volts / 24 volts) while AC Loads are powered by AC (Alternating Current: eg. 110 - 220V). 12 Volts CFL Light are now commercially available.