The utility company will not pay you for power. It will credit your electric account for any power your solar system sends back to the utility grid. Depending on the utility, the credit will carry over each month until used. When you are using electricity when the solar system is not generating power (like at night), you will be using those credits you have previously accumulated.
If your solar system is sized to match your historical consumption, then your utility credits should be nearly depleted at the end of each summer or early fall. If you move these utility credits are lost. When the new homeowner moves in, they will start from zero.