Powerwall backup reserve, Storm Watch and power cuts

One of the big benefits of a Powerwall is backup power. Here's how it works and how to make the most of it.

What happens in a power cut

When the grid goes down, Powerwall disconnects from it automatically and starts powering your home. How much of your home stays on depends on how your system was installed. If you have solar, it can keep recharging the Powerwall during daylight.

After about five minutes without grid power, the Tesla app sends you an alert. You'll get another one when the power comes back.

Making your battery last

• Avoid heavy appliances such as electric heaters, EV chargers, tumble dryers and dishwashers.
• If the Powerwall shuts down because too much was switched on, turn off the big loads. You can then restart it from the Tesla app.
• Report the power cut to your network operator by calling 105.

Backup reserve

Backup reserve is the share of your battery kept aside for power cuts. Your Powerwall won't use this part day to day. You can change it with the slider in the Powerwall settings in the Tesla app. A higher reserve gives more backup, but less battery for saving money each day.

Storm Watch

Storm Watch is available in the UK. It charges your Powerwall to full when the Met Office issues an amber or red warning that mentions possible power cuts. This lets you keep a lower reserve most of the time.

To turn it on:

1. Open the Tesla app and go to Settings, then Storm Watch.
2. Switch on the toggle.