Because solar panels can only collect sunlight to be converted to power when sunlight is available to do so, this creates the obvious disadvantage of powering a property during periods without sunlight. During the day, when you may be away at work and your home is using less power, many areas use net metering to credit you for your excess power production you can send back to the utility company for credit to offset your bill for periods you need to draw power from the grid.
However, these credits typically are not a 1:1 value and thus 12 hours off selling energy to the utility company will not be equal to exactly 12 hours worth of buying that energy back. The idea of battery storage is that the excess power your panels produce throughout the day will first be used to charge your home’s battery for use when solar power isn’t available. If your battery is fully charged, any additional above and beyond that can be applied to net metering.
In this way, only in situations where both solar power and battery power are unavailable will you be required to purchase energy from your utility provider. However, if you’ve been enrolled in net metering, even in these last resort situations you can draw on the credits that you’ve banked with your utility provider. In this way, it may be possible to entirely eliminate your need to pay for kilowatts from your utility company.