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A portable whole house generator is not an oxymoron - it is the $2,000-$3,500 setup that covers most of what an $11,000 standby does. A big portable (7,500-13,000 watts) feeding your panel through a transfer switch runs the practical loads of a typical house. What you give up is automation and central air. What you keep is most of your money. The full tradeoff analysis is in standby vs portable; this page covers the portable-as-whole-house path specifically.
The three components
The generator. The 7,500-9,500W dual-fuel class is the volume seller: Champion, Westinghouse, DuroMax all compete here at $800-$1,500 - see the comparison table and Champion guide. The 12,000-13,000W tri-fuel class (DuroMax XP13000HXT and peers) stretches to genuine whole-house coverage including a small central AC. Dual fuel matters: propane stores indefinitely, gasoline does not.
The transfer switch. Non-negotiable for feeding a panel - a manual transfer switch ($500-$1,500 installed) or an interlock kit ($300-$650 installed) if your panel supports one. Details and code requirements in the transfer switch guide.
The plan. Which breakers are on during an outage is now a human decision. Write the list before the storm: furnace, fridge, freezer, well/sump, kitchen circuit, internet, selected lights. Total their watts with the calculator; that number, not marketing, is your generator size.
What 7,500 watts runs simultaneously, concretely
Furnace fan (800 starting) + fridge (1,200 starting) + freezer (1,000 starting) + well pump (2,000 starting) + internet and LED lighting (200) + a few outlets (500) - comfortably, with headroom, on a 7,500W dual-fuel unit on propane. Add a window AC and you are near the ceiling. Add central AC, a dryer, or an electric water heater and you need the 13kW class or a standby. Motors start one at a time in practice; stagger them and the arithmetic is kinder.
The honest downsides
You are the automatic transfer switch. Storm at 3 a.m. means you, in rain gear, wheeling out a 200-pound unit, connecting the cord, choking the engine, and flipping the switch - then repeating hourly for fuel. Gasoline models need stabilized fuel rotated every few months (propane models skip this). Noise runs 70+ dB on conventional units; inverters are quieter but top out lower. And portables need 15 feet of clearance from the house while running - carbon monoxide again.
If those sound like dealbreakers, you want a standby, and the Generac guide starts that path.
FAQ
Can a portable generator power a whole house? The practical loads of a gas-heated home, yes - that is exactly what the 7,500-13,000W class plus a transfer switch is for. Whole-house including central AC and electric heating/water calls for a standby.
What size portable do I need? Your appliance list decides; most gas-heated homes land at 7,500-9,500W. The calculator includes starting surge and altitude.
Is a portable whole house setup worth it vs standby? If your outages are infrequent and you are willing to manage the machine, absolutely - a third of the cost. If outages are long, frequent, or you travel, the standby's automation earns its price.
Do I need an electrician? For the transfer switch or interlock, yes - permit and inspection included. The generator-to-switch connection is then a cord you plug in.
For homes that want the automatic side instead, the kohler whole house generator and Generac guides cover that market.
