Can a portable power station run a space heater?
Often yes, but only briefly. Most plug-in electric space heaters in the US draw up to about 1,500 W on high (check yours: the label lists the watts). A power station with a big enough inverter can run one, but a heater empties the battery in minutes to a few hours. For staying warm through a night, heating the person works far better than heating the room.
Runtime: the formula
The 0.85 allows for about 15% lost in the inverter and the reserve most power stations keep. A heater with a thermostat cycles on and off once the room warms up, so its average draw can be lower than its rating and runtime longer. In a cold, drafty room it may run almost non-stop.
| Power station capacity | Heater on high (1,500 W) | Heater on low (750 W) | Electric blanket (about 60 W) |
|---|---|---|---|
| 500 Wh | about 17 minutes | about 34 minutes | about 7 hours |
| 1,000 Wh | about 34 minutes | about 1 hour 8 minutes | about 14 hours |
| 2,000 Wh | about 1 hour 8 minutes | about 2 hours 16 minutes | about 28 hours |
| 3,000 Wh | about 1 hour 42 minutes | about 3 hours 24 minutes | about 42 hours |
Example: a 2,000 Wh station gives about 2,000 × 0.85 = 1,700 Wh. On high, 1,700 ÷ 1,500 ≈ 1.13 hours, about 68 minutes. Try your own numbers in the battery runtime calculator.
Check the inverter rating first
A heater on high needs an inverter rated for at least its full wattage, continuously. Heaters have almost no startup surge, but they pull their full load for as long as they run, so pick a power station rated at about 1,800 W continuous or more for a 1,500 W heater. Running an inverter right at its limit makes it hot and loud. If the inverter is rated below the heater, the station will shut off as soon as the heater starts, or limit it if it has a reduced-power mode for resistive loads. See running vs. surge watts.
Smaller power stations, around 300–1,000 W output, can only run a heater's low setting, if at all.
Why heat costs so much battery
Every electric heater turns electricity into heat at the same rate: 1 kWh makes about 3,412 BTU. A "high-efficiency" plug-in heater can't make more heat per watt than any other. It can only aim it better or cycle it more cleverly. Heating a whole room means warming the air and replacing what leaks out, which takes a lot of energy. A power station simply doesn't store much compared with a furnace's fuel supply or the grid.
Better ways to stay warm on battery power
- Electric blanket or heated mattress pad: roughly 40–100 W depending on the setting. It heats you instead of the room, for hours to days on a mid-size station.
- Heated clothing: vests and gloves run off USB power banks at a few watts.
- Run the gas furnace's blower: if your furnace burns gas but its fan needs electricity, a power station or generator may run the blower, typically a few hundred watts. Check with an HVAC technician about safe connection. Never improvise by backfeeding a wall outlet.
- Close off one room and use it with blankets and layers, so whatever heat you have goes further.
Avoid fuel-burning heaters and camp stoves indoors unless they're designed and rated for indoor use. They can produce carbon monoxide, and the U.S. Consumer Product Safety Commission advises battery CO alarms on every level of the home. See the CPSC carbon monoxide page.
Using a heater on a power station safely
- Plug the heater straight into the power station's AC outlet. Don't use a thin extension cord or power strip for a 1,500 W heater.
- Use a heater with a tip-over switch and overheat protection, keep it away from bedding and curtains, and don't leave it running unattended.
- Keep the power station's vents clear: its own fans will run hard at that load.
Frequently asked questions
Can solar panels keep a space heater running?
Only with a very large array in good sun. A 1,500 W heater needs well over 1,500 W of panels in full sun just to break even, and winter days are short. Solar is much better suited to recharging the station between short heating sessions. See peak sun hours.
Can a power station run a heated blanket all night?
Yes, in most cases. A 60 W blanket for 8 hours uses about 480 Wh, or about 565 Wh from the battery after inverter losses, so a station of about 600 Wh or more covers a night. Many blankets also run from a 12 V DC outlet, which wastes less energy.
What about a generator?
A generator can run a space heater for as long as it has fuel. Run it outdoors, at least 20 feet from the house, and run an extension cord in. Compare the options in power station vs. gas generator.