Can your grid-tie solar system include the Tesla Powerwall?
Short answer, yes, since Powerwall can become integrated with a new or existing solar system.
Remember a grid-tie solar system means you remain tied to the utility grid (your utility provider). Consumers, who stay tied to the utility grid with their solar system, are using their solar energy only during the day.
Now you can install Powerwall after your existing system is in use.
According to the Tesla website, “When Powerwall is installed without solar, it can charge from the grid if in Backup-only or Time-Based Control to support you during grid outages and to help you save money on your electricity bill. When Powerwall is installed with solar, it will not be able to charge from the grid.”
Ideally, having a solar system and Powerwall is better for charging purposes and eliminates you from a grid-tie solar system. Nonetheless, you are still saving on your electricity bill if you add back up power later on.
For example, Powerwall gets installed between the utility meter and transfer switch in your electrical box. Keep in mind Powerwall and generators are not integrated directly, so Powerwall does not charge from a generator.
As explained in the Tesla website, “In an outage, Powerwall responds immediately and provides backup power before the generator can detect the outage.
The generator is turned on only when the Powerwall has a low charge, or if loads exceed Powerwall’s maximum output.” The website also explains, “When grid power returns, the generator will turn off and Powerwall can again charge from solar.
If Powerwall is installed with a Manual Transfer Switch, manual operation of the switch is required to power the home with the generator.”
Today, Powerwall and generators are to back up energy, preventing a power outage. Overall, a solar system and Powerwall will allow you to use solar energy during the day and night.
Staying with a grid-tie solar system and adding Powerwall is not a bad idea if you want to save yourself from an unexpected power outage.
References: https://www.tesla.com/support/energy/powerwall/learn/combining-systems