Stand-alone Photovoltaic Systems

Stand-alone photovoltaic systems (SPS) are used when no electricity grid is available. A battery is needed to ensure the availability of electricity at night or at periods with little bright sunlight. Stand-alone systems are often used to cover the electricity needs of a household. Small systems cover the most basic needs (lighting and sometimes TV or radio), larger systems can also power a water pump, wireless phone, refrigerator, electric tools (drill, sewing machine, etc) and a VCR. The system consists of a solar panel, a control unit, battery storage, cables, the electric load and a support structure.