An off-grid solar system is more popular and comes with a power backup. It works independent of the grid. Most home appliances such as TV, cooler, AC, pump etc. can work through this system. For instance, a 1 kW off grid solar system is sufficient for a 2-4 BHK house. But if you also want to run 1 W pump in your home you could use a 3 kW solar system. If you are planning to run an AC then you should use a 5 kW system. For commercial setups like a shop, clinic or small mill, a 10 kW off-grid solar system should be used. It is most common type of solar power system with backup. It works in day and night both, during the day, solar panel charges the battery and runs the home appliances such as Air Conditioners, Cooler, Television and submersible pump. At night, when the sun is not available, Inverter runs your home appliances using the battery power.