Net metering gives you energy credit for returning solar electricity to the grid, and it offsets electricity you take from the utility At night — giving you the full economic value of all the solar energy your solar panels produce. If your solar system is sized properly, you can potentially eliminate all your monthly electric costs.
Solar panels generate the most electricity during the middle of the day when the sun is out. When solar panels produce more electricity than a home uses, the excess generation is sent to the grid. This is where net metering comes into play. When a net metered system sends solar energy to the grid, your electric meter spins backwards and your utility applies a credit for the full retail value of electricity to your account.
Then at night, when your solar panels aren’t producing, you take electricity from the grid, “spinning” your electric meter forward again (meters are all electronic by-directional). At the end of the billing period, the utility nets how much electricity you sent to the grid versus how much you used to determine your final bill – hence the name net metering.