It depends on the system. A battery with an emergency power supply (EPS) or backup gateway can run essential circuits, such as lights, the fridge and the router, during an outage. A standard setup usually cannot run the whole house.
If keeping power on during a cut matters to you, tell your installer at the start so the system is specified for it. Tesla Powerwall 3 with the Tesla Gateway can provide whole-home backup. Solar Heaven will advise which setup fits your needs.
Published October 19, 2026 · All guides