In most cases, if your solar system generates more energy than your home needs at any given time, the excess energy will flow back to the electric grid. Your utility company may provide you with a credit for energy you send back to it.1
There are a few exceptions, however. For example, customers in states that have placed a cap on net metering may be limited in the amount of energy they can export to the grid, as well as any credit received for it. In addition, homeowners whose solar systems have a battery component are able to store excess energy for future use when their systems aren’t generating power, rather than export it to the grid.
1: Sunnova makes no guarantees regarding credit for net energy exported to the electric grid, and any credit provided (now or in the future) is subject to change or termination by executive, legislative or regulatory action.