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The storm passed hours ago, but the street is still dark. Down the block, one porch light is on. Out in that neighbor’s yard, well away from the house, a generator hums under a small canopy, its exhaust pointed at the empty lot. Inside, their fridge is cold, the sump pump is keeping the basement dry and the kids are charging their phones. That’s what a home generator does when it’s chosen well and used safely.
In short: a home generator is an engine that burns gasoline, propane or natural gas to make electricity when the grid goes down. Most homes need a 5,000 to 9,500-running-watt portable generator for essentials, or a 14 to 26 kW standby generator for the whole house. Run any fuel-burning generator outdoors only, at least 20 feet from the house (CPSC).
This page is the start of our Generators section. It explains the four kinds of home generator, shows you how to work out what size you need with real appliance numbers, walks through fuel, transfer switches and costs, and spends real time on the part that keeps families alive: carbon monoxide safety. At the end you’ll find our top picks and links to every detailed guide.
Home generators at a glance
- Four main types: conventional (open-frame) portable, inverter portable, dual-fuel or tri-fuel portable, and permanently installed standby (whole-house) generators.
- Two numbers matter: running watts (what it can deliver all the time) and starting watts (the short burst motors need to start).
- Common sizes: about 2,000 W (lights, phones, a fridge), 3,500 to 5,000 W (essentials plus a sump pump), 7,500 to 10,500 W (essentials plus a 240 V well pump through a transfer switch), 14 to 26 kW standby (most or all of the house).
- Safety first: outdoors only, at least 20 feet from the house, exhaust pointed away from windows, doors and vents, never in a garage even with the door open (CPSC, CDC). Battery-powered or battery-backup CO alarms on every level.
- House wiring: only through a transfer switch or interlock kit installed by a licensed electrician, with a permit where required. Never plug a generator into a wall outlet (FEMA).
- Price range: from about $649 for a small DuroMax inverter to about $1,539 for a big Generac tri-fuel portable (maker prices, October 2026); standby units start around $4,569 before installation, and Generac puts a typical installed system at $8,000 to $16,000.
Outages are getting longer, too. The U.S. Energy Information Administration (EIA) reports that customers averaged about 11 hours without power in 2024, nearly twice the yearly average of the decade before, mostly because of hurricanes like Beryl, Helene and Milton.
The four types of home generator
Every home generator does the same basic job, but they differ a lot in power, noise, fuel and how they connect to your house.
| Conventional portable | Inverter portable | Dual-fuel / tri-fuel portable | Standby (whole-house) | |
|---|---|---|---|---|
| Typical running watts | 3,000 to 10,500 W | 1,800 to 3,900 W (more in pairs) | Same as conventional or inverter, a bit less on propane or natural gas | 10 to 26 kW (air-cooled home units) |
| Fuel | Gasoline | Gasoline, some propane | Gasoline plus propane (dual) or plus natural gas (tri) | Natural gas or propane, piped in |
| Noise | Loud (Champion lists 74 dB(A) at 23 ft for its 9,200 W tri-fuel) | Quieter (Champion lists 53 dB(A) at 23 ft for its 2,500 W inverter) | Depends on the frame | Housed in a sound cabinet; Generac lists 65 to 67 dB(A) at 23 ft |
| Power quality | Fine for motors and tools | Clean, steady power for electronics | Depends on the type | Built for whole-house loads |
| Starts when the power fails | No, you set it up | No | No | Yes, automatically, through an automatic transfer switch |
| Best for | Most power per dollar | Fridge, electronics, RV, quiet neighborhoods | Fuel flexibility in long outages | Hands-off backup for the whole home |
Conventional (open-frame) portable generators
An engine on a steel frame with wheels, a fuel tank and an outlet panel. They give the most watts for the money: a Westinghouse WGen9500DFc makes 9,500 running watts on gasoline and has a list price of $1,399. Most bigger models have a 120/240 V L14-30R outlet made to feed a transfer switch, and an electric start. The trade-offs are noise, weight (often 200 pounds or more) and fuel use.
Inverter generators
An inverter generator converts the engine’s raw output into clean, steady power and lets the engine slow down at light loads. That makes it quieter and thriftier: Honda rates its 1,800 W EU2200i at 8.1 hours on less than a gallon at a quarter load. Most are small, but larger ones such as the Champion 4500W Dual Fuel Inverter (3,500 running watts on gasoline) can run a fridge, freezer, lights and a sump pump. Many can be paired with a second unit for more power. See inverter vs conventional generators and the best inverter generators.
Dual-fuel and tri-fuel generators
Dual-fuel models run on gasoline or propane; tri-fuel models add natural gas. Propane stores for years without going stale, and natural gas never runs out unless the utility shuts it off, which matters in long outages when gas stations close. Expect a little less power on gaseous fuels: Champion’s 9,200 W tri-fuel makes 8,500 running watts on propane and 7,500 on natural gas. Our best dual fuel generators guide compares them.
Standby (whole-house) generators
A standby generator sits on a pad outside the house, runs on your natural gas line or a propane tank, and starts by itself through an automatic transfer switch within seconds of an outage (Kohler quotes a 10-second response for its home units). Generac, Kohler (now part of Rehlko), Briggs & Stratton and Champion make the common air-cooled models from about 10 to 26 kW. They aren’t sold on Amazon: you buy them through a dealer who handles the site visit, permits, gas line, pad and transfer switch. Note that natural-gas ratings are lower than the model name: Generac’s 22 kW Guardian makes 19.5 kW on natural gas. Costs are covered in whole house generator cost.
What size generator do you need?
Sizing is simpler than it looks. Champion’s method, used by most makers: list everything you want to run at the same time, add up their running watts, then add the starting watts of the single biggest motor, since motors rarely start at the same moment. Pick a generator whose running watts cover the first number and whose starting watts cover the second, with some room to spare.
The best numbers are on your own appliances’ labels. If you don’t have them, here are Champion’s published ranges for common outage loads:
| Appliance (Champion wattage chart) | Running watts | Starting watts |
|---|---|---|
| Refrigerator | 150 to 400 | 800 to 1,200 |
| Freezer | 100 to 500 | 500 to 1,000 |
| Sump pump, 1/3 HP | 500 to 800 | 1,000 to 1,600 |
| Sump pump, 1/2 HP | 800 to 1,050 | 1,300 to 2,150 |
| Well pump, 1/2 HP | 750 to 1,000 | 1,500 to 2,000 |
| Well pump, 1 HP | 1,000 to 2,000 | 2,000 to 4,000 |
| Furnace fan, 1/2 HP | 300 to 800 | 800 to 1,600 |
| Window AC, 10,000 BTU | 900 to 1,200 | 1,800 to 2,400 |
| Central AC, 2 to 4 ton | 2,000 to 5,000 | 3,500 to 8,000 |
| Microwave | 600 to 1,200 | – |
| LED bulb | 8 to 15 each | – |
| TV, 32 to 55 inch | 80 to 400 | – |
| Laptop or phone charger | 20 to 100 | – |
| Space heater | 750 to 1,500 | – |
| Electric water heater | 3,000 to 4,500 | – |
Three worked examples
We used the top of each Champion range to stay on the safe side. These are our estimates; your own labels may be lower.
- Essentials: fridge (400), freezer (500), ten LED bulbs (150), TV (400), phones and laptop (100) = 1,550 running watts. Add the fridge’s 1,200 starting watts and you need about 2,750 W at start-up. A 3,000 to 4,500 W inverter covers it comfortably.
- Essentials plus sump pump and furnace fan: add a 1/2 HP sump pump (1,050) and a furnace fan (800) for 3,400 running watts, plus the pump’s 2,150 starting watts = about 5,550 W. That points to a 5,000 to 7,500-running-watt generator. A furnace is hard-wired, so it needs a transfer switch or interlock.
- Add a 1 HP well pump: 3,400 + 2,000 = 5,400 running watts, plus the well pump’s 4,000 starting watts = about 9,400 W. Most well pumps are 240 V and hard-wired, so you need a generator with a 240 V outlet (L14-30R or 14-50R), a transfer switch and something like the Westinghouse WGen9500DFc or Champion 9,200 W tri-fuel.
Central air conditioning, electric water heaters, electric ranges and dryers are what push a home from a portable into standby territory. Our what size generator do I need guide has a printable worksheet and more examples.
Fuel: gasoline, propane or natural gas
- Gasoline: the most power per tank and easy to find, until the stations near you lose power too. It goes stale in storage, so treat stored gas with a stabilizer. STA-BIL says its Storage formula keeps fuel fresh for up to 24 months at 1 ounce per 2.5 gallons, and to run the engine 5 minutes after adding it. Rotate your cans: pour older fuel into the car and refill.
- Propane: stores for years in the tank and burns cleaner, so carburetors gum up less. A 20-pound grill tank doesn’t last long, though: Champion lists 5 hours at half load for its 9,200 W tri-fuel. DuroMax suggests at least a 40-pound tank for its 13,000 W models.
- Natural gas: no refueling at all. Standby generators use it, and tri-fuel portables can, through a quick-connect line. Having a licensed plumber or gas fitter add the connection is the safe route, with a permit where required.
How much fuel will you burn? Take the maker’s figures: the WGen9500DFc runs about 8 hours on its 6.6-gallon tank at half load, so a day at half load uses roughly 20 gallons of gasoline (our estimate). Running the generator in shifts, a few hours on and a few off, keeps the fridge cold and cuts that a lot. Ready.gov says a closed fridge keeps food cold for about 4 hours and a full freezer about 48 hours. For more on each fuel, see propane, natural gas and petroleum energy.
How to connect a generator to your house
There are four safe ways, from simplest to most automatic. Anything that touches house wiring is installed by a licensed electrician, with a permit where required.
- Extension cords. Plug the fridge, lamps and chargers into heavy-duty outdoor cords run from the generator. No installation, but it can’t reach hard-wired loads like a furnace or well pump.
- Inlet box plus manual transfer switch. An electrician mounts a power inlet outside (a Reliance Controls PBN30 is an L14-30 inlet for generators up to 7,500 W) and a small transfer switch beside your panel with 6 or 10 chosen circuits (Reliance Pro/Tran kits). You plug in one cord and flip the circuits over.
- Interlock kit plus inlet. A metal plate on your main panel that makes it impossible to have the main breaker and the generator breaker on at the same time, so you can power any circuit in the panel. It must be made for your exact panel brand and series and listed for it, such as Square D’s HOMCGK2C for certain Homeline panels or Siemens’ ECSBPK01. Generic “fits all” plates aren’t the same thing.
- Automatic transfer switch (standby). Standby generators come with or need an automatic transfer switch that senses the outage, starts the generator and switches the house over. Generac also sells a 200 A whole-house manual transfer switch for portable generators of 5 kW and up with a 30 A outlet.
Never “backfeed” your house by plugging the generator into a wall outlet or dryer outlet with a double-ended “suicide cord.” FEMA warns never to plug a generator into a wall outlet: power can flow back out onto the utility lines and injure line workers or neighbors, and it bypasses your home’s protection. Our generator transfer switch guide compares switches, interlocks and inlets, with costs.
Generator safety: carbon monoxide comes first
Generator exhaust is loaded with carbon monoxide (CO), a gas with no color or smell. The CDC says more than 400 Americans die each year from unintentional CO poisoning not linked to fires, and more than 100,000 visit an emergency department. CPSC says an average of nearly 100 people die each year in the U.S. from CO poisoning from portable generators alone. Many happen during outages, when a generator is run in a garage, a basement or too close to an open window.
The rules, from CPSC, CDC, FEMA and Ready.gov:
- Outdoors only. Never inside a home, garage, basement, crawlspace, shed or other enclosed area, even with the doors or windows open. Not on a porch or in a carport either.
- At least 20 feet from the house, with the exhaust pointed away from windows, doors and vents. Close nearby windows.
- CO alarms on every level and outside sleeping areas, battery-operated or with battery backup (a plug-in alarm without a battery is useless in an outage). Test them monthly.
- Know the symptoms: headache, dizziness, weakness, upset stomach, vomiting, chest pain and confusion (CDC). If you feel sick or an alarm sounds, get everyone into fresh air and call 911.
- Turn it off and let it cool before refueling (FEMA). Gasoline spilled on a hot engine can catch fire. Store fuel in approved containers away from the house and any flame.
- Keep it dry. Follow the maker’s instructions for wet weather; don’t touch it with wet hands.
Buy a generator with a CO shut-off
CPSC recommends portable generators with a carbon monoxide shut-off, which stops the engine when CO builds up around it, and points to models certified to the PGMA G300-2023 or UL 2201-2023 standards. Every big maker now offers one, under different names:
| Maker | CO shut-off name | Example models |
|---|---|---|
| Honda | CO-MINDER | EU2200i, EU3200i |
| Champion | CO Shield | 2500W and 4500W dual-fuel inverters, 8,000 W and 9,200 W tri-fuel |
| Generac | COsense | GP3300i, GP8000E, GP9500E |
| Westinghouse | CO Sensor (automatic shutdown); look for a “c” at the end of the model | iGen2200c, iGen5000DFc, WGen7500DFc, WGen9500DFc |
| DuroMax | CO Alert | XP2300iH, XP13000HX |
| Yamaha | CO sensor with automatic shutoff | EF2200iS |
A shut-off is a backup, not a permission slip. Champion says plainly that CO Shield is not a substitute for indoor CO alarms or for running the generator safely outdoors. Read our full how to run a generator safely guide, with a printable power outage checklist.
First Alert CO606 Plug-In CO Alarm
- Plug-in with battery backup
- 85 dB alarm
- One test/silence button
Kidde 30CUD10-V Smoke + CO Alarm
- Smoke and CO in one
- Voice alerts
- 10-year limited warranty
STA-BIL Storage Fuel Stabilizer, 32 oz
- Fresh fuel up to 24 months (maker)
- 1 oz treats 2.5 gal
- 32 oz treats 80 gal
What a home generator costs
| Type | Examples (maker prices, October 2026) | Also budget for |
|---|---|---|
| Small inverter, 1,800 to 2,500 W | DuroMax XP2300iH about $649; Honda EU2200i about $1,199 (MSRP) | Cords, fuel cans, stabilizer, CO alarms |
| Mid-size inverter, 2,500 to 3,900 W | Generac GP3300i about $939 (MSRP); Westinghouse iGen5000DFc $1,299 list | Same |
| Large portable, 7,500 to 10,500 W | Generac GP8000E about $1,179 (MSRP); DuroMax XP13000EH about $1,299; Westinghouse WGen9500DFc $1,399 list; Generac GP9500E tri-fuel about $1,539 (MSRP) | Inlet box and transfer switch or interlock, installed by an electrician; a 30 A or 50 A cord |
| Standby, 14 to 26 kW (unit only) | Generac Guardian 14 kW from $4,569; Kohler 20RCA from $6,016; Generac Guardian 22 kW from $6,119; Briggs & Stratton PowerProtect 26 kW from $6,970 | Transfer switch, pad, gas line, electrical work, permits and installation |
For a standby generator, the installed price is what counts. Generac says installation of a home standby generator averages $8,000 to $16,000 including the generator, system equipment and installation, and that the dealer sets the installation price. It varies widely with the size, your gas service, the distance to the panel and local permit rules, so get 2 to 3 quotes from authorized dealers. Plan on maintenance too: Generac recommends service every 6 months by an authorized dealer.
There’s no federal tax credit for generators in 2026. The federal residential clean energy credit (25D) never covered fuel-burning generators, and it ended for batteries and solar installed after December 31, 2025. A few states and utilities have programs for backup power; search DSIRE or ask your utility.
Generator, home battery or power station?
A generator isn’t the only way to keep the lights on. Batteries make no exhaust, so they can sit indoors, and they’re silent. Generators win on long outages and big loads, because you can keep adding fuel.
| Portable generator | Standby generator | Portable power station | Whole-home battery | |
|---|---|---|---|---|
| Use indoors? | Never | Outside on a pad, installed to code | Yes | Installed indoors or out per the maker |
| How long it runs | As long as you refuel | As long as the gas flows | Until the battery is empty; recharge from wall, sun or car | Hours to days; recharges from solar |
| Noise | Loud | Moderate | Quiet | Quiet |
| Typical cost | About $650 to $1,550 plus wiring | $8,000 to $16,000 installed (Generac) | About $250 to $2,800 and up | Installer quote; varies widely |
Many families combine them: a power station indoors for the fridge, Wi-Fi and a CPAP overnight, and a generator outside during the day to run the big loads and recharge the battery. Compare the options in portable power stations, the best power station for home backup and our home battery backup guide.
Our top generator picks
Prices change often. The prices below are what we saw at the maker or a major retailer in October 2026; check the current price before you buy. Where we couldn’t confirm a current price, we left it out.
Westinghouse WGen9500DFc
- 9,500 W gas / 8,500 W propane
- L14-30R and 14-50R outlets
- CO Sensor with automatic shutdown
Champion 9200W Tri Fuel with CO Shield
- 9,200 W gas / 7,500 W natural gas
- 25-ft natural gas hose included
- CO Shield
DuroMax XP13000EH
- 10,500 W gas / 10,000 W propane
- L14-30R and 14-50R outlets
- CO sensor shutdown
Champion 4500W Dual Fuel Inverter
- 3,500 W gas / 3,150 W propane
- 61 dB(A) at 23 ft
- CO Shield
Generac Guardian 22kW (7042)
- 22 kW propane / 19.5 kW natural gas
- Starts automatically
- MSRP from $6,119, unit only
The Westinghouse WGen9500DFc is our pick for most houses: enough power for essentials plus a well pump or furnace through a transfer switch, propane as a backup fuel, remote start and a CO sensor with automatic shutdown. If you have natural gas, the Champion 9200W Tri Fuel can run on it. For a fridge, freezer, lights and electronics with less noise, the Champion 4500W Dual Fuel Inverter is the sweet spot. The Generac Guardian 22kW is sold and installed through Generac dealers, not online. The full reasoning, with specs and downsides, is in our best generator for home power outage guide.
See the Guardian 22kW at Generac
Which generator guide do you need?
| If you want to… | Read |
|---|---|
| Pick a generator for power outages | Best generator for home power outage |
| Get a quiet generator with clean power | Best inverter generators |
| Run on gasoline or propane | Best dual fuel generators |
| Work out your wattage | What size generator do I need |
| Understand inverter vs open-frame | Inverter vs conventional generator |
| Connect a generator to your panel | Generator transfer switch guide |
| Stay safe and prepared | How to run a generator safely (with outage checklist) |
| Price a standby generator | Whole house generator cost |
Home generator questions
How far from the house should a generator be?
At least 20 feet, says CPSC, with the exhaust pointed away from windows, doors and vents. The CDC says more than 20 feet from any window, door or vent. Never run it in a garage, basement, shed, carport or on a porch, even with doors open. Put battery or battery-backup CO alarms on every level of the house as a second line of defense.
Can I run a generator in my garage with the door open?
No. CPSC, the CDC and FEMA all say never to run a generator in a garage, even with the doors and windows open. Carbon monoxide builds up faster than an open door can clear it, and it seeps into the house through attached-garage walls and doors. Run it outdoors, at least 20 feet away, and follow the maker’s instructions for running it in wet weather.
What size generator will run a whole house?
For most homes with central air, a 20 to 26 kW standby generator, sized by a dealer after a load calculation. A large portable (9,500 to 10,500 running watts) can run most essentials, a well pump and a furnace through a transfer switch, but usually not central AC, an electric range, a dryer and a water heater together. Remember natural-gas ratings are lower than the name.
Can I plug a generator into a wall outlet?
No. Plugging a generator into a wall or dryer outlet, called backfeeding, can send power back onto the utility lines and injure line workers, and it can start a fire in your home. FEMA says never to do it. Use extension cords to individual appliances, or have a licensed electrician install a transfer switch or a listed interlock kit with a permit where required.
Is an inverter generator better for home backup?
For essentials and electronics, often yes: it’s quieter, uses less fuel at light loads and makes clean power. But most inverters top out around 3,500 to 3,900 running watts and have no 240 V outlet, so for a well pump or furnace on a transfer switch, a large open-frame generator gives more power for the money.
How long can a generator run?
A portable runs as long as you refuel it and maintain it; makers rate one tank at roughly 8 to 18 hours depending on the model and load. Turn it off and let it cool before every refuel, and check the oil as the manual says. Standby generators run on piped gas for days, but still need oil and filter service, which Generac recommends every 6 months.
Keep exploring
Start with the best generator for a home power outage, then size yours with what size generator do I need and plan the hookup with our transfer switch guide. If you’d rather skip fuel and fumes, see home battery backup and portable power stations. Browse every article in the generators category, or read about the fuels themselves: propane and natural gas.