Photovoltaic (PV)

Photovoltaics (PV) is the field of technology and research related to the application of solar cells for energy by converting sun energy (sunlight, including sun ultra violet radiation) directly into electricity.

The key components of a photovoltaic power system are the photovoltaic cells (also called solar cells) interconnected and encapsulated to form a photovoltaic module (the commercial product), the mounting structure for the module or array, the inverter (essential for grid-connected systems and required for many off-grid systems), the storage battery and charge controller (for off-grid systems only).

PV technology can be employed in a variety of applications:

Off-grid domestic PV systems like solar home systems:

• Provide electricity to households and villages that are not connected to the utility electricity network (also referred to as the grid)
• Provide electricity for lighting, refrigeration and other low power loads
• Have been installed worldwide
• Are often the most appropriate technology to meet the energy demands of off-grid communities

Off-grid non-domestic PV installations:

• Are used in locations where small amounts of electricity have a high value
• Were the first commercial application for terrestrial PV systems
• Provide power for a wide range of applications, such as telecommunication, water pumping, vaccine refrigeration and navigational aids
• Make PV commercially cost competitive with other small generating sources

Grid-connected distributed PV systems:

• Provide power to grid-connected customers or directly to the electricity network (specifically where that part of the electricity network is configured to supply power to a number of customers rather than to provide a bulk transport function)
• May be on or integrated into the customer's premises, often on the demand side of the electricity meter, on public and commercial buildings, or elsewhere in the built environment

Grid-connected centralized PV systems:

• Perform the functions of centralized power stations
• Supply power that is not associated with a particular electricity customer
• Primarily supply bulk power, rather existing on the electricity network to perform specific functions.
  

Source: IEA PVPS