AC is one of the hardest things to run off a battery — big running watts, a bigger startup surge, and it runs for hours. Here's what actually works.
| Air conditioner | Running watts | Startup surge | Min capacity for ~3 hrs |
|---|---|---|---|
| Window 5,000 BTU | ~450–500 W | ~1,000–1,200 W | ~2,000 Wh |
| Window 8,000 BTU | ~700 W | ~1,800 W | ~3,000 Wh |
| Window 12,000 BTU | ~1,100 W | ~2,800 W | ~3,600 Wh+ |
| Portable AC | ~1,000–1,400 W | ~2,000–2,500 W | ~3,600 Wh+ |
A 5,000 BTU unit (~500W) on a 1000Wh power station (≈850Wh usable) runs about 1.5–3 hours depending on how often the compressor cycles and how hot it is. Bump to 2,000Wh and you get a few hours; for overnight cooling you need 3,000–4,000Wh. Inverter/heat-pump ACs sip less and stretch this further.
Batteries and AC are a tough match — cooling is energy-hungry. A power station is great for a few hours of relief, a nap, or taking the edge off; for all-night or all-day AC you want a large (3,600Wh+) expandable unit plus solar, or a generator. For sizing anything else alongside it, the calculator handles the surge math automatically.
Add your AC and everything else you'll run; the power station calculator gives you the output and capacity to look for, surge included.
Open the calculator →Related: what can a power station run · for camping & RV · vs a generator
A small 5,000 BTU window unit (≈500W, ≈1,100W surge) yes — on a unit with 1,000W+ output and ~2,000Wh for a few hours. Bigger AC needs 2,000W+ output and 3,000Wh+.
A 5,000 BTU unit runs ~1.5–3 hours. Larger units, less.
Realistically 3,000–4,000Wh with a 2,000W+ inverter, ideally plus solar.