The very commonly seen type of home solar solution, Grid tied home solar solutions work without batteries. These are the most inexpensive ones as well as the most easy to design as well as install. They have very few components and are quite simple to use. This makes them very popular.
Now the point, however, arises that without a battery, owners of solar power will not able to able to store any excess power. Stored power is useful as it can be used during times of emergency or a blackout. It can also be used when solar panels are not operational, like during night. Without a battery, the best medium of power backup is the local grid.
Any excess power that is produced is sent to the grid and when you need power then you draw on power from the grid without the use for a battery. Here, net metering can serve useful in which the homeowners can get a bill credit for any excess power sent to the grid and the same credit can be used to purchase power from the grid when there is not enough solar power.
Sometimes, it might happen that the grid power may go out as well. In such a scenario, people using grid tied home solar solution will lose power. Even the inverters will get disconnected from the utility grid when power goes out to ensure safety.