Powerwall: how many hours of backup during an outage in Québec?

The question comes up with every storm: "If I install a Powerwall, how long will it last?" The honest answer: it depends on what you choose to power during the outage.

Essentials mode — 12 to 24 hours

This is the most common setup. You keep running: the fridge, lighting, supplemental heat (baseboards in the main room or a heat pump in eco mode), internet and a few key outlets. A 13.5 kWh Powerwall typically lasts 12 to 24 hours in this mode.

This is what most of our clients choose. The essential-circuits panel is designed with you to identify your real needs.

Whole Home Backup — 4 to 8 hours

The whole home stays powered, as if nothing happened. Range, dryer, A/C — everything works. Of course, that draws a lot, and runtime drops. For this setup, two or more Powerwalls are recommended.

The Powerwall + generator combo

For areas prone to very long outages (a 4-to-5-day ice storm), a standby natural-gas generator + Powerwall combo is unbeatable. The Powerwall covers the first hours silently, then the generator takes over while the Powerwall recharges.

And in Québec specifically?

Our cold climate adds a variable: heating accounts for a huge share of consumption. That's why we always assess insulation and heating type before sizing the system. A well-insulated home lasts much longer than one that loses 5 °C per hour.

We've been installing Powerwalls on the North Shore for several years. If you want an honest estimate for your home, ask us for an assessment — it's free.