Pick a battery system, tap the appliances you want to keep on, and set how long the power is out. You'll see whether the system can start those loads, run them together, and how many hours it lasts — for every battery Solar X installs.
The battery backs up your whole electrical panel. Every appliance you tap counts.
Select appliances to see runtime
This system supplies 11.4 kW running and 17.1 kW to start motors.
Estimates only. Actual runtime depends on appliance age, weather, battery temperature and state of charge. Final system design is confirmed by Solar X after a site assessment.
The Solar X Battery Backup Calculator runs three checks on every configuration. The start-up check assumes every motor you selected (fridge, furnace fan, heat pump, sump pump) starts in the same second, because a compressor can draw five to eight times its running power for a moment. The running check adds up every selected appliance as if they were all on at once. The runtime uses typical duty cycles — a fridge compressor runs about a third of each hour, lights about half — plus the inverter's own standby draw, against the battery's usable energy after conversion losses.
Power and energy ratings come from each manufacturer's datasheet. Low-voltage 48 V systems deliver about 94% of stored energy to your outlets; high-voltage systems about 97%. Single-cabinet low-voltage batteries are limited by the battery's discharge current, not the inverter, which is why some 16 kWh systems can't start a heat pump and a well pump together.
The calculator is battery-only: it does not count solar recharging during the outage, and it assumes the battery starts full. Real outages often start with a partly used battery, and cold garages reduce capacity, so treat the result as an upper estimate.
Ontario homeowners may qualify for Home Renovation Savings Program rebates of up to $5,000 on a qualifying battery. See our battery storage guide or backup power options for how whole-home and essential-panel backup differ. Final system design is confirmed by Solar X after a site assessment.