Does Solar Work During a Power Outage? What Ontario Homeowners Need to Know
Most homeowners are surprised to learn that a standard solar system shuts off when the power goes out, even on a sunny day. Here is why, and how adding a battery keeps your home running.
TRU Off Grid · October 17, 2026
The Short Answer
A standard grid-tied solar system does not work during a power outage. When the grid goes down, the solar inverter shuts off within moments, even in full sun. To keep power on during an outage, the solar needs to be paired with a battery and a hybrid inverter that can run your home on its own.
Why Grid-Tied Solar Shuts Off
It is a safety rule. When the grid is down, utility crews are working on the lines. If thousands of solar systems kept pushing power into those lines, they could injure the people fixing them. So every grid-tied solar inverter is required to stop the moment it loses the grid signal. This is called anti-islanding.
The result: a home with solar panels and no battery is just as dark during an outage as the house next door.
How a Battery System Keeps the Lights On
A solar and battery system adds two things.
A hybrid inverter and battery: the inverter can run your home from the battery and the solar, without the grid.
Automatic switching: on EG4 systems this is the GridBOSS or a backup sub-panel. When the grid fails, it disconnects your home from the grid automatically, so your system can safely keep running. Your solar keeps charging the battery during the day, and the battery runs the house at night.
When the grid comes back, the system reconnects on its own and goes back to normal. You do not have to flip anything.
What It Looks Like in an Ontario Outage
Summer storm: long sunny days refill the battery every afternoon. A properly sized system can ride through a multi-day outage on solar and battery alone.
Winter ice storm: days are short and panels may be covered in snow, so solar adds less. This is where battery size matters, and where an automatic backup generator earns its place. EG4 inverters can start an inverter-type generator when the battery runs low and stop it once the battery is charged.
If you are not sure how much battery you need, see our battery sizing guide.
Already Have Solar?
If your home already has solar panels, you can still get backup power. We do not bolt a second system onto your old one. We remove the existing solar inverter and connect your panels directly into a new EG4 or EP Cube 2.0 system, so you end up with one system, one app and one warranty.
One note: Ontario's Home Renovation Savings rebate is for new solar and battery installed together, so homes that already have solar usually do not qualify. We will tell you up front what applies to your home.
Adding Solar and Battery Together
If you are starting fresh, installing solar and a battery together as a non-exporting system can qualify for up to $10,000 through the Home Renovation Savings program. See our rebate guide for the details.
TRU Off Grid designs, permits and installs solar and battery backup systems with EG4 and Canadian Solar EP Cube 2.0 across Ontario, from our shop in Milton. Send a recent hydro bill to jacob@truoffgrid.com or call Jacob Collier at 647-914-9699, and we will show you what it takes to keep your home running the next time the grid goes down.
