Can a power station run a space heater?

Only a big one. Most electric space heaters draw 1,500 W on high, so you need a continuous inverter rating above 1,500 W — a 1,000 W unit simply can't run one. Even when it can, a 1,500 W heater burns through a battery fast: about an hour per kilowatt-hour of usable capacity. Space heaters are the least battery-friendly load there is.

What size power station do I need to run a window air conditioner?

For an 8,000 BTU window unit (~650 W running), the running wattage is modest, but the compressor's startup surge (~1,800 W) is the real hurdle — the inverter's surge rating must clear it or the AC won't start. A unit with an 1,800 W+ inverter and a surge rating around 3,000 W+ handles it comfortably. Capacity then decides how many hours you get.

Can I run a microwave on a power station?

Yes, if the inverter is large enough. A "1,000 W" microwave actually pulls about 1,500 W from the wall (that rating is cooking output, not input), so you need a continuous inverter above 1,500 W. Because microwaves run only a few minutes at a time, the energy cost is small — it's the continuous wattage, not capacity, that's the limiter.

Why won't my power station start a motor appliance even though the wattage seems fine?

Because of startup surge. Motors — in fridges, pumps, and AC compressors — pull a brief inrush spike several times their running wattage when they kick on. If the inverter's surge rating can't cover that spike, it trips instantly, even though the running wattage is well within the continuous rating. Always check the surge number for anything with a motor.

What's the difference between running watts and surge watts?

Running (or rated) watts is the steady draw while a device operates; surge (or peak) watts is the momentary spike when a motor or compressor starts. A power station has two matching ratings: a continuous inverter rating and a higher surge rating. The device's running watts must be under the continuous rating, and its surge under the surge rating.

Wattage

Can a power station run an AC, space heater, or microwave?

These heavy loads are limited by watts, not watt-hours: the inverter's continuous rating has to clear the running draw, and its surge rating has to clear the startup spike.

The most common power-station disappointment is a unit that won't even start an appliance — not because the battery is small, but because the inverter is. Here are the loads people most over-ask, with real running watts, startup surge, and the smallest unit that clears each.

6 min readUpdated July 9, 2026

The heavy loads, with the number that actually stops you

These are our sourced appliance figures. The running draw sets the minimum continuous inverter rating; the startup surge (on motor loads) sets the minimum surge rating. The last column is the smallest unit in our surge-verified sample that can both run and start each one.

Sourced appliance draws vs the smallest station that clears them
Appliance	Running draw	Startup surge	Smallest sample unit	Source
Window AC (8,000 BTU)	650 W	1,800 W	EcoFlow DELTA 3	2026-07-06
Space heater (1,500W)	1,500 W	none (resistive)	EcoFlow DELTA 3	2026-07-06
Microwave (1,000W cooking power)	1,500 W	none (resistive)	EcoFlow DELTA 3	2026-07-06
Electric kettle (1.7L)	1,500 W	none (resistive)	EcoFlow DELTA 3	2026-07-06
Sump pump (1/3 HP)	800 W	2,000 W	EcoFlow DELTA 3	2026-07-06

Notice the pattern: a ~1,200 W unit can’t start any of the 1,500 W resistive loads, and the window AC’s ~1,800 W surge rules out units with thin surge headroom. Once an inverter clears ~1,800 W continuous with a healthy surge rating — like the EcoFlow DELTA 3 class and up — the question shifts from “can it start?” to “how long will it last?”

Watts start it; watt-hours sustain it

Clearing the wattage only means the appliance turns on. How long it runs is a separate question set by usable capacity — and heaters and AC units empty a battery quickly because they draw heavily and continuously.

A 1,500 W space heater pulls roughly a kilowatt-hour every 40 minutes, so even a big 2 kWh station gives you only a couple of hours of heat — battery heating is best for short bridges, not overnight. A window AC, drawing ~650 W while its compressor cycles, is gentler and can run for hours on a large unit. For anything in this class, look at the biggest units on our best power stations ranking — for example the EcoFlow DELTA Pro 3 or Anker SOLIX F3800 — and size the runtime with the tool.

Frequently asked questions

Can a power station run a space heater?: Only a big one. Most electric space heaters draw 1,500 W on high, so you need a continuous inverter rating above 1,500 W — a 1,000 W unit simply can't run one. Even when it can, a 1,500 W heater burns through a battery fast: about an hour per kilowatt-hour of usable capacity. Space heaters are the least battery-friendly load there is.
What size power station do I need to run a window air conditioner?: For an 8,000 BTU window unit (~650 W running), the running wattage is modest, but the compressor's startup surge (~1,800 W) is the real hurdle — the inverter's surge rating must clear it or the AC won't start. A unit with an 1,800 W+ inverter and a surge rating around 3,000 W+ handles it comfortably. Capacity then decides how many hours you get.
Can I run a microwave on a power station?: Yes, if the inverter is large enough. A "1,000 W" microwave actually pulls about 1,500 W from the wall (that rating is cooking output, not input), so you need a continuous inverter above 1,500 W. Because microwaves run only a few minutes at a time, the energy cost is small — it's the continuous wattage, not capacity, that's the limiter.
Why won't my power station start a motor appliance even though the wattage seems fine?: Because of startup surge. Motors — in fridges, pumps, and AC compressors — pull a brief inrush spike several times their running wattage when they kick on. If the inverter's surge rating can't cover that spike, it trips instantly, even though the running wattage is well within the continuous rating. Always check the surge number for anything with a motor.
What's the difference between running watts and surge watts?: Running (or rated) watts is the steady draw while a device operates; surge (or peak) watts is the momentary spike when a motor or compressor starts. A power station has two matching ratings: a continuous inverter rating and a higher surge rating. The device's running watts must be under the continuous rating, and its surge under the surge rating.