Sizing
Generator Sizing Guide
A rough framework for thinking about capacity before an installer runs the real load calculation.
Generator Sizing Guide
The right generator size comes down to one question: how much of your home do you want running during an outage? An installer confirms the exact kW rating with a load calculation, but these three tiers are a useful starting point.
Essentials only (7–10 kW)
Refrigerator, sump pump, a few lights and outlets, and Wi-Fi — enough to keep the basics running.
Most of the home (14–20 kW)
Essentials plus most circuits, though possibly not central air conditioning at full load.
Whole home (22 kW+)
Everything, including HVAC, simultaneously — the closest to not noticing an outage happened.
This page is a general framework, not a substitute for a licensed installer's load calculation, which accounts for your home's actual panel, appliances, and simultaneous demand.