Battery duration

Maximize your backup 

Your Sunrun system is built for reliable power. Here’s how to manage your home energy and get the most out of your battery when the lights go out.

Battery charge percentage when the outage hits

The single biggest factor in your battery's duration is its starting charge. You can easily view your battery’s charge level in the Sunrun app. Ideally, you want a full 100% when an outage hits.

If your system is running in a self-powered or time-based control mode, your battery might not be at 100%. Don't worry, this mode is likely in your best interest. Find out why on our optimization page.

To get the full benefits of battery when an outage is or isn’t occurring, always keep the Storm Watch feature enabled! When your battery is notified of severe weather events that could cause an outage, it automatically works to get as close to a full charge before the storm arrives.

Understand your battery’s support capacity

Many Sunrun customers with a single battery are able to have whole-home backup. This means the battery is connected to all your home's circuits.

However, the question isn't whether your battery can power your whole home, but for how long.

Capacity vs. Duration

The decision of what your battery supports is made during installation, based on your home’s size and energy needs.

• Partial home backup: If your home's energy needs surpass what a single battery can provide, the battery will be installed to support only essential circuits that you determine with your Sunrun installer. This prioritizes duration during an outage, meaning you will be able to backup most of your home with the exception of a few heavy loads such as a pool pump, EV charger, or a 2nd A/C unit. 

• Whole-home backup: If you have specific high-demand appliances you’d like to run in an outage, or if your home is larger, you may need to install multiple batteries to cover whole-home backup and sufficient duration.

In systems where whole-home backup is possible with a single battery, you still control the duration by choosing which circuits to run in an outage.

Manage your loads

Understanding battery life is simple: Every appliance draws energy, and some drain your power faster than others.

Think of your home battery like a smartphone battery. Using GPS navigation, video call, or gaming apps drains a phone battery more quickly than sending a text or checking our email. The same is true with what appliances your home battery supports. 

Here’s our recommendation for which loads to support in an outage in order to help your battery last as long as possible while still supporting your critical needs: 

Heavy power appliances shouldn’t be used or should be used sparingly. 

While a battery can handle whole-home backup, most homeowners find that running only essentials with one or two batteries is enough for their needs. If you want life to continue completely as normal in an outage, you may want to install multiple batteries.

Gain ultimate control with a smart panel

If you want circuit-level control over your backup power, the SPAN smart electrical panel is your perfect companion.

The challenge without SPAN: Without a smart panel, providing whole-home backup means you control the loads by manually turning off non-essential appliances. If someone forgets and cranks the A/C, your battery life suffers the consequences.

The SPAN solution: SPAN gives you circuit-level control at the tap of a finger through the SPAN app.

• Categorize: You set your home’s circuits into “Must Have,” “Nice to Have,” and “Non-Essential”.

• Automate: When an outage occurs, your battery only powers the “Must Have” and “Nice to Have” circuits. When the battery hits 50% charge, the “Nice to Have” circuits are automatically turned off.

• Monitor: See which appliances are using the most energy and what energy source (solar, battery, grid) your home is currently drawing from.

Ready for ultimate energy control? Learn more about SPAN