Backup Power

During a power outage, how long will Powerwall last?

An average home uses approximately 25 kWh of energy per day. A small home may use as little as 10 kWh and a large home may use 40 kWh or more per day. Each Powerwall provides 13.5 kWh of usable energy for backup power. You can use the Tesla mobile app to monitor your usage and conserve power to extend your backup coverage for a day or more. Additionally, when Powerwall is paired with solar it can continue to recharge and has the potential to run your home indefinitely. Understand how long Powerwall will last in an outage based on your daily routines.

During a power outage, how quickly does Powerwall restore power to my home?

Powerwall can detect an outage, disconnect from the grid and bring power back to your home in a fraction of a second. Unlike backup generators, Powerwall can keep your appliances running without interruption. You will not even notice that the power went out.

How do I know if I'm using backup power?

In the event of a grid outage, the seamless transition to Powerwall can mean many people may not know they are running on backup power.

The Tesla mobile app provides notifications when Powerwall disconnects from and reconnects to the grid, allowing you to manage your home power consumption. When your home is disconnected from the grid, you may want to lower your consumption to extend the amount of time Powerwall can provide power. During an outage, the Tesla mobile app will show the grid as unavailable, with your Powerwall supporting your home.

How do I configure my grid outage notifications?

Ensure your Tesla mobile app is up to date. From the Tesla mobile app, go to 'Settings' and select 'Notifications.' From there, you can set your preferences for receiving all notifications, including Power Outages. Also ensure that your device settings allow notifications from the Tesla mobile app. 

You will receive a notification when there has been a sustained grid outage, and a second notification once power has been restored.

How many appliances can I back up with a single Powerwall?  What loads will require multiple Powerwalls to back up?

Each Powerwall can provide up to 5 kW of continuous power. You can back up any number of appliances, so long as their combined power usage does not exceed the total power rating of your Powerwalls. Learn how you can estimate the power needs of typical home appliances.

During a utility power outage, how do I extend the amount of time my home can run on Powerwall?

The best way to extend your usage of Powerwall during an outage is to limit the energy consumption of your home. You can do this by monitoring your use of non-essential or energy-hungry appliances like air conditioners, plasma TVs, hairdryers, and hot tubs. Learn more about typical power consumption of different household appliances

What happens if I overload the system's backup capabilities?

If you exceed Powerwall's power (5kW each) or energy (13.5kWh each) capabilities, it will safely shut down similar to your home circuit breaker. To resume Powerwall operation, turn off all lights and appliances in your home, then toggle the on/off switch located on the side of Powerwall. If, after an extended utility outage, Powerwall is depleted, then wait for the next sunny day before toggling the on/off switch.

What types of backup does Powerwall support?

Powerwall can detect an outage, disconnect from the grid, and bring power back to your home in a fraction of a second. By reacting more than 100 times faster than typical standby generators, Powerwall can keep your appliances running without interruption.

Whole Home Backup

Tesla will recommend the number of Powerwalls needed to back up your entire home. You can add more Powerwalls to keep your house operational during longer outages.

Essential Load Backup

If your electrical situation doesn’t allow for a whole home backup, you can back up selected essential loads such as lights and outlets. Since these require less power, a single Powerwall will typically be sufficient.