Understanding how your solar panels behave during a power outage is important for setting expectations and planning your energy resilience. The answer depends on whether you have a standard grid-tied system or a system equipped with battery storage.
With a standard grid-tied solar system — the most common type of residential installation — your panels automatically shut down when the grid goes out. This safety feature, called anti-islanding protection, is required by law and built into every grid-tied inverter. It prevents your solar system from sending electricity into power lines that utility workers may be repairing, protecting them from electrocution.
This means that during a grid outage, even if the sun is shining brightly and your panels are capable of producing power, a standard grid-tied system will not supply electricity to your home. Once the grid is restored, your system automatically resumes normal operation.
If backup power during outages is important to you — and it increasingly is for homeowners across the Northeast — the solution is adding a battery storage system. Products like the Tesla Powerwall, Enphase IQ Battery, and LG RESU store excess solar energy during the day and can power essential loads during an outage. When the grid goes down, these systems automatically disconnect from the grid and create a self-contained "microgrid" for your home.
A typical home battery stores 10 to 15 kilowatt-hours of energy — enough to run lights, refrigeration, internet, and phone charging for 8 to 12 hours or more. Multiple batteries can be installed for greater capacity. During a daytime outage, your panels can recharge the battery while simultaneously powering your home.
Several Northeast states offer battery incentives, making this backup solution increasingly affordable.