Recommended size: 15,000–22,000W+
A 15,000–22,000W+ standby generator is what you need for whole-home backup including central AC. These permanently installed units start automatically within seconds of a power outage and run on natural gas or propane, so there is no refueling. They include a 200A transfer switch for direct panel connection.
Market-leading whole-home standby generator. Includes 200A transfer switch. Powers everything including central AC automatically when the grid goes down.
Central AC draws 10,500+ starting watts on its own, which pushes the total home load past what any portable generator can handle reliably. Standby generators solve this by delivering 15,000–22,000W+ continuously from a permanent installation connected to your home's natural gas line or a large propane tank. They start automatically when the grid goes down and switch back when power returns. Installation requires a licensed electrician and typically costs $500–$1,500 on top of the unit price. The 200A transfer switch included with both models below handles the full capacity of most residential electrical panels.
| Generator | Starting W | Running W | Fuel | Noise |
|---|---|---|---|---|
| Generac Guardian 22kW Standby | 22,000W | 22,000W | Natural Gas / Propane | 67 dB |
| Champion 22kW aXis Standby | 22,000W | 22,000W | Natural Gas / Propane | 67 dB |
Generac
★4.2
Market-leading whole-home standby generator. Includes 200A transfer switch. Powers everything including central AC automatically when the grid goes down.
Champion
★4.2·249 ratings
Strong Generac alternative with 200A transfer switch included. Competitive pricing and quiet 67 dB operation for whole-home backup.
The accessories most generator owners add to run safely and connect to the house.
Transfer / Interlock
★4.7·1,733 ratings
Lets you safely back-feed your panel from one inlet. Confirm it matches your breaker brand and amperage.
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Power Cord
★4.8·2,827 ratings
Heavy 10-gauge twist-lock cord rated to 7,500W, the standard link between a portable unit and your inlet box.
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Weather Cover
★4.6·2,107 ratings
Keeps rain and snow off the unit so you can run it through a storm with proper ventilation.
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CO Safety
★4.7·19,762 ratings
Generator exhaust is the top cause of CO poisoning during outages. A battery alarm keeps working when the grid is down.
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Fuel Care
★4.8·35,997 ratings
Treats 40 gallons and keeps stored fuel fresh for up to 24 months so the engine starts when you need it.
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