An off-grid solar system is a photovoltaic system that is not connected to the electrical grid. The system can generate and store energy on its own and provides it for further use by the consumer. As it is not connected to the grid, the energy generated by the solar panels needs to be stored to provide electricity to the user at all times (even at night when photovoltaic modules do not generate any energy).
What is an off-grid solar system?
The most basic components of an off-grid solar system:
The role of the electricity generator in an off-grid solar system is fulfilled by the solar panels, which can generate electricity from the Sun.
Charging & discharging controller
In order to prevent the battery from overcharging and over-discharging, a solar controller must be used. It controls the charging voltage of the batteries, battery level and the voltage and current parameters of the solar panels so that they can provide the maximum power output that is possible.
The most common energy storage solutions consist of battery packs (mainly Lithium-Ion, Lead Acid or Gel batteries). They are used to store the energy generated by the solar panels to use it when solar panels do not generate enough of it.
All of the electrical appliances that use electricity in the system are called load. Load is also referred to as the sum of energy that is consumed by the appliances.
An inverter is used in off-grid systems that require AC Voltage output. It converts DC voltage to AC voltage which then can be used in houses in the same way as the grid electricity. They are most commonly used in households or summer cabins, where electricity is provided to the electrical sockets in the form of AC voltage. In off-grid systems that run solely on DC voltage (e. g. solar lighting systems) an inverter is not necessary.
An energy meter might be added to the system to measure the energy consumption of the system. It is not an obligatory component in off-grid systems.
Why off-grid solar systems?
Off-grid solar systems are commonly used in solar lighting or solar pumping locations where it is difficult or inconvenient to run an AC power cable to. They are a great source of power for sign lighting, as they generate and store enough energy to enable lights to operate at night without inconvenient cable connections.
These systems are perfect for homeowners that live in remote areas and the grid is far away from their households. Everyone can generate electricity on their own without having to connect the house to the electrical grid, which in some cases might not be possible. They are commonly used in summer cabins, as it is easier and more cost-efficient than connecting the cabins to the electrical grid.
They make a phenomenal solution for campers, yachts and other means of transport that need electricity but are mobile, and connecting them to the grid would be difficult. Solar panels are even used on the International Space Station, space rovers, and space shuttles as they can generate power in space or on other planets!