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Can a portable generator power a whole house?

A big portable can cover most of a modest home — with two important limits: central AC, and how you connect it.

What a large portable can do

A 9,000–12,000W portable, wired through a transfer switch, can run a modest home's essentials: fridge, freezer, furnace, lights, well or sump pump, and outlets. What usually doesn't fit is central air conditioning running alongside everything — its surge pushes most portables over the edge.

The connection matters

You must use a transfer switch or interlock (NEC Article 702). Never run a cord from the generator into a wall outlet — that "backfeed" can electrocute utility line workers and is illegal.

Common questions

Can a portable generator power a whole house?

A large portable (9,000–12,000W) can power most of a modest home's essentials through a transfer switch, but usually not central AC plus everything at once. Whole-home coverage with central AC typically needs a standby unit.

Do I need a transfer switch?

Yes — to power house circuits safely and legally you need a transfer switch or interlock. Never backfeed through an outlet; it can kill utility workers.