Tesla Powerwall 3 installed in a garage.

Does Tesla Powerwall Work With a Whole Home Backup Generator?

The Tesla Powerwall 3 fully integrated home backup system is an incredibly popular option for homeowners looking to add backup power and maximize their solar energy usage. But what if you already have or are considering installing a whole home generator for backup power?

Can the two systems work together?

The short answer is yes, Tesla Powerwall can be compatible with whole home backup generators when installed properly with a transfer switch. It’s important that, if there are different installation companies, they work together to help ensure a successful end result: peace of mind for you and your family.

Here’s a more in-depth look at how Powerwall and generators can be integrated:

Powerwall Installation With Generators

To use Powerwall alongside a generator, the system must be installed with either an external automatic transfer switch (ATS) or a manual transfer switch (MTS).

The Powerwall system is installed between the utility meter and the generator transfer switch and can charge from solar while the grid is operational and when the grid is down during an outage. However, Powerwall and the generator are not directly integrated which means Powerwall does not charge from the generator (Powerwall is charged by your solar panels).

When a power outage occurs, Powerwall automatically detects the outage and instantly powers your home with stored backup energy. This all happens 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.

When grid power returns, the generator will turn off, both the ATS and Powerwall system will reconnect to the grid and Powerwall will resume normal operation. If Powerwall is installed with an MTS, manual operation of the switch is required to power the home loads with the generator, and to connect the home loads back to the Powerwall system or the grid.

A home at night during a storm
With Tesla Powerwall, your home will have power even when the grid goes down.

Automatic vs Manual Transfer

If installed with an automatic transfer switch, the process of switching between Powerwall, generator, and utility power is seamless. The ATS automatically transitions sources as needed.

With a manual transfer switch, you will need to manually operate the switch to power your home via the generator during an outage. You’ll also need to manually switch sources when utility power is restored.

Generator As Backup Battery Extender

Integrating Powerwall with a whole home generator essentially gives you extended backup power capabilities. Powerwall provides immediate backup ahead of the generator kicking in. And the generator can run indefinitely to keep the home powered as needed during an extended outage (as long as you have enough fuel stored).

For homeowners looking for whole home backup power and energy self-reliance, combining Tesla Powerwall with a generator is an excellent solution. The two systems complement each other very well when installed correctly with a transfer switch. There is more information about this available on Tesla’s website.