Remember the concept of net-metering: the majority of systems are still connected to the utility grid. So whenever your system isn’t producing as well, you are drawing electricity from the utility company for all of your energy needs at any moment of the day or week. That’s OK, because you’ll receive credit for the electricity you produce on sunny days, and if your production matches your use (no matter which day you’re producing or using), you’ll still break even. So, likewise, if your system is producing and you’re not there to use it, you’ll be sending power to the grid and receiving a credit that will benefit you later on.

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