AC (Alternating Current)

The direction of electrical current reverses, usually as many as (60) times per second. Electricity transmission networks use AC because voltage can be controlled with relative ease.

AMPERE (amp)

A unit of electrical current or rate of flow of electrons. One volt across one ohm of resistance causes a current flow of one ampere. One ampere is equal to 6.235 x 10 18 electrons per second passing a given point in a circuit.


Any number of Photovoltaic modules connected together electrically to provide a single electrical output. An array is a mechanically integrated assembly of modules or panels together with support structure (including foundation and other components, as required) to form a free-standing field installed unit that produces DC power.


CELL (battery)

A single unit of an electrochemical device capable of producing direct voltage by converting chemical energy into electrical energy. A battery usually consists of several cells electrically connected together to produce higher voltages. (Sometimes the terms cell and battery are used interchangeably).

CELL (solar)

The smallest, basic Photovoltaic device that generates electricity when exposed to light.


DC Direct Current

A one way flow of electric current. Typical sources of direct currents are electric cells, rectified power units and direct current generators. This is the current flow produced by a solar system. To be used for typical 120 volt or 220 volt household appliances, it must be converted to AC (alternating current).



The ratio of power output of a Photovoltaic cell to the incident power from the sun or simulated sun sources under specified standard insolation conditions.


The rate at which electricity flows through an electrical conductor, usually measured in amperes (amps).


Energy resulting from the flow of charge particles, such as electrons or ions.


A negatively charged particle. The movement of electrons in an electrical conductor constitutes an electric current.