Portable power station vs generator for home backup: which is better?

When the power goes out, you want the lights, the fridge and maybe the furnace or sump pump running. A portable power station is a big rechargeable battery with outlets. A generator is an engine that burns gas or propane. Both keep things running. They're good at different jobs.

Side by side

	Portable power station	Portable generator
Energy it holds	What's on the label, often 1,000 to 3,000 Wh	Roughly 4 to 5 kWh per gallon of gas (from makers' run times)
Where it can run	Indoors or out; no exhaust	Outdoors only, 20+ feet from the house
Noise	Near silent (fans only)	Loud to fairly quiet (inverters)
Refill	Recharge from the wall, solar, car or a generator	Pour in fuel or swap a propane tank
Big loads and 240 V	Limited by its inverter; few have 240 V	Common, with L14-30 or 14-50 outlets
Upkeep	Keep it partly charged in storage	Oil changes and fresh fuel

How much energy each holds

Here's the big difference, in numbers.

A power station stores what's on its label: 1,000 Wh is 1 kWh.

A generator turns fuel into energy as it runs. You can work out how much from the maker's run time:

Energy (kWh) = watts × hours ÷ 1,000

Worked example

One maker's 9,500 W generator lists 12 hours at 25% load on a 6.6-gallon tank. 25% of 9,500 W is 2,375 W.

• Energy from a full tank: 2,375 × 12 ÷ 1,000 = 28.5 kWh
• Per gallon: 28.5 ÷ 6.6 = about 4.3 kWh
• On 5 gallons: about 21.6 kWh

That's about ten fully charged 2,000 Wh power stations. A small 1,800 W inverter works out about the same, around 4.7 kWh per gallon at 25% load.

In an outage, that's the whole story. A power station gets you through hours or a night or two. A generator with enough fuel gets you through days.

What a power station can run

A modern full-size fridge uses about 1.0 to 1.6 kWh a day, based on ENERGY STAR's certified models. So:

Power station	Fridge alone (estimate)
1,000 Wh	about 12 to 20 hours
2,000 Wh	about 25 to 41 hours
3,000 Wh	about 38 to 62 hours

Add lights, a router and phone charging and those hours shrink. Try your own mix in the calculator above. It's set for a fridge on a 2,000 Wh station.

Power stations are great for:

• a fridge for a day, a CPAP for a night or two, lights, Wi-Fi and phones
• apartments and homes with no safe place to run a generator
• short, frequent outages
• quiet nights

They struggle with:

• electric heat, water heaters and central AC
• 240 V well pumps, unless the station supports 240 V
• long outages with little sun

See can a power station run a refrigerator and what size power station for a CPAP.

What a generator does better

• Long outages. More fuel means more hours. You can refuel in a minute.
• Big loads. Sump pumps, well pumps, furnace fans and window AC units with big starting surges.
• Connecting to your house. With a 240 V outlet and an electrician-installed interlock kit or transfer switch, a generator can power chosen circuits. See interlock vs transfer switch.

The trade-offs are real. A generator is loud, needs fuel on hand, and makes carbon monoxide. CPSC warns that one generator produces as much CO as hundreds of cars. It can only run outdoors, far from the house, which is harder in storms and in apartments.

Recharging and refueling

Power station: Recharge times vary a lot. Generac, for example, lists 2.1 and 3.3 hours to reach 80% from the wall for its two station models. Solar is slower, and Generac notes weather and panel angle affect output.

Generator: Shut it off and let it cool before refueling. Gas goes stale in storage. Generac recommends draining the fuel if you'll store the generator more than 30 days. Propane doesn't go stale, but gives a little less power.

Storage: Generac advises storing its power stations at 30% to 60% charge and recharging every three months.

The best of both

Many people use a generator and a power station together:

1. Run the generator outdoors during the day. Power the fridge and charge the station.
2. At night, shut the generator off. Run the fridge, lights and CPAP from the silent battery.
3. Save fuel, sleep better, and the generator isn't running unattended overnight.

If you live in California, note that CARB rules are pushing new small portable generators toward zero emissions. Battery equipment doesn't need CARB certification. See CARB-compliant generators.

Which should you buy?

• Mostly short outages, light loads, or no safe outdoor spot? Start with a power station.
• Outages that last days, a well pump, or you want to power house circuits? Get a generator, sized for your loads. Our size calculator helps.
• Both, if you can. A generator for energy, a station for quiet and safety at night.

If you choose a generator, it must run outdoors only, at least 20 feet from your home, never in a garage or on a porch. Read our generator carbon monoxide safety guide.