View source for What is an off-grid PV system?/en

[[Category:Basic concepts]]
The term off-grid encompasses many different system designs as it simply signifies an electrical system that is not connected to the electric grid. Off-grid power systems are installed to provide [[Electricity and energy|electricity]] in areas where the normal grid does not exist. The most common off-grid power system is a photovoltaic (PV) system with batteries. [[PV module|PV modules]] are used to generate electricity when the sun is shining, but the sun is a variable resource - it sets every day and is frequently hidden by clouds - therefore an off-grid PV system uses batteries to store some of the [[Electricity and energy|energy]] generated by the PV source for later use. This is similar to how rainwater collection systems function. It can be helpful to make this comparison between the two systems as a rainwater collection system uses simple components that are common in most parts of the world that serve similar functions to the more complicated components in an off-grid PV system. In the simplest sense both of the systems capture a variable natural resource - rainwater and sun - when it is abundant and store it for later use when it is scarce. To do so both of them have six basic components: a form of collection, a means of distribution, a way to regulate in-flows, storage, a way to regulate out-flows and a means of consumption.

==Rainwater collection system==
[[File:Rainwatercollection.png|frame|center|'''Rainwater collection system:'''<br />''(1)'' The roofs surface collects the rainfall. ''(2)'' The gutter and pipes distribute the rainwater. ''(3)'' A valve is used to regulate in-flow of water to avoid overfilling the tank. ''(4)'' A tank stores rainwater for later use. ''(5)'' A valve is used to regulate out-flow of water to avoid emptying the tank completely. ''(6)'' A sprinkler can consume water from the tank as needed.]]

==Off-grid PV system==
[[File:Pvsystem.png|frame|center|'''Rainwater collection system:'''<br /> ''(1)'' The [[:Category:PV source|PV modules]] collect the sun's rays and convert it into electric energy ''(2)'' [[:Category:Wire and cable|Wires]] distribute the electric energy created from the PV modules. ''(3)'' The [[:Category:Charge controller|charge controller]] is used to regulate in-flow of electric energy to avoid overcharging the battery. ''(4)'' The [[:Category:Energy storage|energy storage system]] stores electric energy for later use. ''(5)'' A [[Low voltage disconnect]] - which can be stand-alone or integrated into the [[:Category:Charge controller|charge controller]] and [[:Category:Inverter|inverter]] - regulates out-flow of electric energy to avoid emptying the battery completely. ''(6)'' The [[:Category:Loads|loads]] - light or other appliances - can consume electric energy from the [[:Category:Energy storage|energy storage system]] as needed.]]