An off-grid solar system needs no utility grid present, as the name implies.
While the electronics on an off-grid system are less complex than a battery back-up system, the system design of an off-grid system requires great attention. In an off-grid system there is less margin for error in sizing a system since it is the sole source of power. Efficiency is not optional!
To go off-grid is a lifestyle commitment, but it can be done!