Last verified: October 1, 2026
A standby generator turns itself on within seconds of an outage and can run your whole house for days on natural gas or propane. A portable generator costs a fraction of the price but has to be wheeled out, fueled with gasoline and connected by hand, and it usually powers only your essentials. Which one fits depends on three things: your budget, how long your outages last and whether someone will always be home to run it.
Side-by-side comparison
| Portable generator | Home standby generator | |
|---|---|---|
| Typical price | $500–$2,500 for the generator | $3,000–$6,000 for the unit; $6,000–$11,000 installed for most whole-house setups |
| Connection to the house | Interlock kit or manual transfer switch plus inlet box ($400–$1,300 installed) | Automatic transfer switch, included in the installation |
| Starting | You start it (pull cord or electric start) | Starts automatically in seconds, even if you are away |
| Fuel | Gasoline, sometimes propane (dual fuel) | Natural gas line or large propane tank |
| Runtime | Roughly 8–12 hours per tank at moderate load, then refuel | Days, as long as the gas supply lasts |
| Typical output | 3,000–10,000 watts | 10–26 kW for most homes |
| Central air conditioning | Rarely | Yes, with the right size or a soft starter |
| Main safety risk | Carbon monoxide if run too close to the house | Low when installed to code by a professional |
| Maintenance | You: oil, fresh fuel, test runs | Automatic weekly exercise plus yearly service |
Price ranges come from HomeGuide’s generator cost data and transfer switch cost data (2026). Runtime per tank varies a lot by model and load; check the spec sheet of the model you are considering.
When a portable generator is the better choice
- Your outages are usually under a day. Refueling every 8–12 hours is manageable for a short outage.
- You only need essentials. A fridge, a sump pump, a furnace blower, lights and Wi-Fi fit in a 5,000–7,500 W portable. Our size calculator shows the minimum rating for the appliances you pick.
- Your budget is under about $3,000. A good portable plus a professionally installed interlock kit and inlet box usually stays well under that figure.
- You rent or may move soon. A portable goes with you; a standby unit stays with the house.
When a standby generator is worth the extra money
- Outages last days, not hours, as they do after hurricanes and ice storms.
- Nobody may be home to start it. A sump pump in a flooded basement, pipes in a freezing house or an elderly relative living alone all depend on power that comes on by itself.
- You need central air or whole-home coverage. Portables rarely handle a central AC compressor.
- You don’t want to store and handle gasoline. A standby unit runs on the gas supply you already have, or on a propane tank that is refilled by delivery.
The safety difference is bigger than most people think
Portable generators produce large amounts of carbon monoxide. The U.S. Consumer Product Safety Commission found that portable generators were linked to more than 85% of non-fire carbon monoxide deaths involving engine-driven tools in its long-term data, and that half of those deaths happened between November and February. Its advice: run a portable generator only outdoors, at least 20 feet from the house, away from windows, doors and vents, and install battery-operated CO alarms (CPSC).
The second danger is backfeeding: plugging a generator into a household outlet with a double-ended cord. It can send power back into the utility lines and electrocute line workers. A portable must be connected through an interlock kit or a transfer switch installed by a licensed electrician.
What it costs over five years: a simple comparison
This example assumes a home with two or three outages a year, one of them lasting about two days. All figures are rough planning numbers.
| Cost over 5 years | Portable (7,500 W) + interlock | Standby (14 kW, natural gas) |
|---|---|---|
| Purchase and installation | About $1,000 + $600 | About $8,000 |
| Maintenance | Oil, stabilizer, a spare spark plug: under $50 a year | Annual dealer service: a few hundred dollars a year |
| Fuel during outages | Gasoline, bought and stored by you | Natural gas from your existing line |
| Your time | Start, refuel every 8–12 hours, store fuel | None during an outage |
| Rough 5-year total | About $2,000–$2,500 | About $9,500–$10,500 |
The standby costs roughly four to five times more. What you get for the difference is automation, whole-home coverage and no fuel handling. Whether that is worth it is the question we answer in Is a Whole House Generator Worth It?
A middle option: a smaller standby unit
If a full 22–26 kW system is out of budget but you want automatic power, a 10–14 kW standby unit wired to an essential-circuits transfer switch covers the fridge, sump or well pump, furnace, lights and outlets in a few rooms. According to HomeGuide, 7–10 kW units cost $2,000–$3,000 and 13–16 kW units $3,000–$4,500 before installation, compared with up to $12,000 for the largest air-cooled models.
Frequently asked questions
Can a portable generator run my whole house?
Rarely. Even large portables (around 9,000–10,000 running watts) struggle with central air plus other loads. They’re best for essentials through an interlock kit or transfer switch.
How long does a standby generator last compared with a portable?
Standby generators are built for permanent installation with scheduled maintenance and typically come with longer warranties (5 years is common; Champion offers 10 on its 14 kW system). Portables are usually covered for shorter periods. Compare the specific warranties you’re offered.
Which is easier to maintain?
A standby unit tests itself weekly and is serviced on a schedule, often by a dealer. A portable needs you to manage fuel, oil and test runs. See our maintenance checklist.
Quick decision guide
- If your outages are short and rare, buy a portable and pay an electrician to install an interlock kit and inlet box.
- If your outages last more than a day, or nobody is home to start a generator, get quotes for a standby unit.
- If you need central AC or whole-home power, a standby generator is the realistic option.
- Whatever you choose, install CO alarms on every floor and never run a portable indoors or in a garage.