What Happens During a Power Outage? How SBSS Backup Power Works

A home battery does not automatically mean every appliance will run normally for an unlimited period during an outage. Reliable backup starts with a clear design: which circuits will be supported, how much power they can draw at once, and how long the available battery energy is expected to last.

When the grid fails, a properly installed Smarter Power Smart Battery Storage System detects the outage, isolates the supported electrical system from the utility and begins supplying stored energy. The changeover is rapid and automatic, so homeowners do not need to find fuel, move a portable generator or manually connect extension cords.

There are two common approaches.

Critical-load backup

Critical-load backup supplies selected circuits such as refrigeration, lighting, internet equipment, a sump pump and heating controls. Because the system is supporting fewer loads, the battery can generally last longer.

Broader home backup

Broader or whole-home-style backup allows more of the house to remain available, but high-demand equipment must be managed carefully. Electric ranges, resistance heating, central air conditioning, hot tubs, large pumps and EV chargers can consume stored energy quickly or exceed the system’s simultaneous power capability.

Runtime depends on energy, not just the battery label. A simple estimate is usable battery capacity divided by the average supported load.

For example, if a system has 15 usable kWh available and the backed-up circuits average 1.5 kW, the mathematical estimate is approximately 10 hours. Real runtime will change as appliances cycle, solar production varies and the battery maintains its programmed reserve.

Solar can make the system considerably more resilient. Conventional grid-connected solar usually shuts down during a utility outage for safety. When solar is paired with an appropriately configured battery inverter and backup system, it can continue serving the isolated home and recharge the battery when production is greater than the supported loads.

That does not guarantee endless operation, but it can turn a fixed amount of stored energy into a renewable daily supply during an extended outage.

Installation quality is as important as equipment capacity. Ontario energy-storage projects must use approved equipment and follow Electrical Safety Authority requirements for location, clearances, capacity and connection. Review the ESA’s energy-storage approval guidance.

Homeowners should also consider sensitive electronics. A fast battery transfer is designed to make outages far less disruptive, but equipment requiring true uninterrupted power may still need a dedicated UPS.

The best backup plan is not “power everything until the battery is empty.” It is a prioritized strategy that protects the loads your household genuinely needs. Smarter Power sizes and programs the SBSS around that goal while preserving the ability to reduce hydro costs during normal grid operation.