What does PV or Photovoltaic mean?

Photovoltaic (PV) essentially means electricity from the energy of the sun and is derived from the words “photo” with the Greek meaning light and “voltaic” meaning voltage. The term “photovoltaic” is used to describe a process known as the “photovoltaic effect” the process by which a material such as silicon converts sunlight into electricity.

 

PV cells are laminated to a thin sheet of glass. Sunlight in the form of photons strike the PV cells, exciting electrons in the silicon. An electric current is generated when the electrons are collected by wiring that is incorporated into the PV cells.

 

photo_voltaic_panelsA solar panel consists of multiple PV cells, the amount will depend on the output voltage and current required of the solar panel. Solar panels range in size from around 5 to over 400watts peak output and produce DC (direct current).

 

Multiple solar panels are connected in strings, to build a solar array. The size of the array will depend on how much energy is required to be generated, generally up to 10kWp for a standard domestic installation in New Zealand.

 

The DC energy from the solar array can be stored in batteries and then converted to AC by an inverter as when required or you can convert the solar energy directly to AC with a grid connected inverter and feed any excess energy into the national grid for credits.