When the power goes out, most households don't need to run everything. They need to keep phones charged, lights on, the internet up, food cold and, for some people, a medical device running. A portable power station handles exactly that kind of list, silently and indoors, without fuel or fumes. This guide explains what a power station can and can't do, how to size one for your home, and the features that separate a good backup from a disappointing one.
What a power station is (and isn't)
A portable power station is a large rechargeable battery with a built-in inverter and a panel of outlets: household-style AC sockets, USB-A and USB-C ports, and usually a 12 V car-style socket. You charge it from a wall outlet, solar panels or a car, then draw power from it when you need it.
It is not a whole-home backup system. A typical 1 kWh station stores about as much energy as a modern refrigerator uses in a day, give or take. It can't run central air, an electric range or an electric water heater for any useful time, and most can't power 240 V appliances at all. What it does well is run a carefully chosen set of essentials for hours or, with solar recharging, for days.
Step 1: List your essentials
Write down what you want to keep running in an outage, how many watts each device uses, and how many hours a day you'd run it. The wattage is usually on a label or in the manual. A plug-in watt meter is the best way to measure real consumption, especially for appliances that cycle on and off.
The figures below are rough, illustrative ranges only. Your devices may be very different, so measure or check the label.
| Device | Typical running watts (rough) | Notes |
|---|---|---|
| Phone charging | 5–20 W | Only while charging |
| Wi-Fi router and modem | 10–30 W combined | Runs continuously |
| LED light bulb | 5–15 W each | Use only where needed |
| Laptop | 30–90 W | Less when idle |
| CPAP machine | 30–90 W | Much higher with a heated humidifier; check the manual |
| Refrigerator | 100–250 W while running | Cycles on and off; start-up surge can be several times higher |
| Chest freezer | 80–200 W while running | Cycles; holds temperature well if kept closed |
Step 2: Size the capacity
For each device, multiply watts by hours of use to get watt-hours (Wh), then add them up. For example: a router and modem at 20 W for 12 hours is 240 Wh; four LED bulbs at 10 W for 5 hours is 200 Wh; phone charging for a family might be 60 Wh. That's 500 Wh before the fridge.
Refrigerators are trickier because they cycle. A useful way to estimate is to check the yellow EnergyGuide label, which lists estimated yearly kilowatt-hours; divide by 365 to get a rough daily figure. A fridge rated at 500 kWh a year averages about 1.4 kWh (1,400 Wh) a day. In an outage you can reduce that by keeping the door closed and running the fridge for a few hours at a time.
Finally, allow for losses. Converting battery power to AC typically costs 10 to 20 percent, so divide your total by about 0.85. A 500 Wh essentials list becomes roughly 590 Wh of station capacity. Add a fridge and you're quickly into the 1,000 to 2,000 Wh range, which is why stations around 1 kWh are such a popular backup size.
Step 3: Check the output
Capacity is the size of the tank; output is the size of the hose. The station's continuous AC rating must cover everything you run at the same time, and its surge rating must cover start-up spikes from motors and compressors. Refrigerators, well pumps and sump pumps are the usual culprits. If a station's surge rating is too low, it will shut off when the compressor kicks in. Many 1 kWh-class stations offer 1,500 to 1,800 W continuous output, enough for most fridges plus small loads, but check your appliance.
What separates good stations
LiFePO4 battery chemistry
Lithium iron phosphate (LiFePO4, or LFP) has become the standard for home backup stations. Manufacturers commonly rate LFP stations for thousands of charge cycles, and the chemistry is generally regarded as more thermally stable than the NMC lithium-ion cells used in older or lighter units. The trade-off is a little more weight.
Fast, flexible recharging
Wall recharging speeds vary from many hours to around an hour on the fastest units. Fast charging matters when the grid flickers back on briefly. Solar input matters for long outages: check the maximum watts and the voltage range the station accepts, and whether it has the connectors you'll need. Car charging is a useful backup but slow.
Pure sine wave output
Reputable stations produce pure sine wave AC, which is what motors, chargers and sensitive electronics expect. It's worth confirming on any budget unit.
UPS or EPS mode
Some stations can sit between the wall and a device and take over automatically when the grid drops. Switchover times vary by model; if you want to protect a desktop computer or medical device without interruption, check the published switchover time and the device maker's guidance.
Expandability
Some stations accept add-on batteries. That lets you start with a manageable size and add capacity later, which can be cheaper than replacing the station.
Storage behavior
A backup sits unused most of the time. Look for a low self-discharge rate and follow the manufacturer's storage advice; many recommend recharging every few months. Some stations have apps that remind you.
Power station or fuel generator?
| Power station | Portable fuel generator | |
|---|---|---|
| Indoor use | Yes, no exhaust | Never; outdoors only, away from openings |
| Noise | Near silent | Loud |
| Runtime | Limited by battery; refill with solar or wall | As long as fuel lasts |
| Big loads (well pump, 240 V) | Usually not | Often, with a transfer switch |
| Maintenance | Recharge periodically | Fuel, oil, stabilizer, regular test runs |
For many households, a power station inside for essentials, plus a generator outdoors for bigger loads, is the most flexible plan. If you use a generator, read our generator safety and accessories guide first.
Safety and placement
- Follow the manufacturer's guidance on ventilation, and keep vents clear.
- Keep the station dry and off the floor in flood-prone areas.
- Don't daisy-chain power strips from the station; plug essentials in directly.
- Stop using any unit that's swollen, damaged or unusually hot.
The bottom line
A portable power station is the easiest, safest way to keep essentials running through an outage. Size it from a real list of devices: add up watt-hours, allow about 15 percent for losses, and confirm the continuous and surge ratings cover what runs at once. A LiFePO4 station in the 1 kWh class, with solar input for longer outages, covers most households' essentials. Our three picks below are all in that class. To add solar, see our solar generator sizing guide.
