Scenarios › Power station for CPAP all night (and for several nights)

What size power station runs a CPAP all night?

A CPAP without the heated humidifier sips power, so the real question is how many nights you get per charge. Here is the size for one night with comfortable headroom — and what it takes to cover several nights or to run the heated humidifier.

356 Whcapacity needed

40 Wrunning watts

40 Wsurge to clear

8.0 hruntime horizon

This load: CPAP Machine (no humidifier). Want to tweak it? Open the full sizing tool and adjust the appliances and hours.

What size you need

You need about 356 Wh — and 28 units fit. The smallest sufficient is the Goal Zero Yeti 500X; we never push more capacity than your load can use. Surge to clear: 40 W.

The math
Running watts (everything on at once) = 40 W
Surge watts (worst single startup + the rest running) = 40 W
Average draw (cyclic loads counted by their duty cycle) = 40 W
Watt-hours = 40 W × 8.0 h ÷ 90% usable reserve = 356 Wh

Goal Zero Yeti 500Xsmallest that fits

505 Wh 300 W cont · 1,200 W surge ~11 h on this load $$

A half-kWh unit for electronics and overnight medical loads.

NMC · ~9 h AC; up to 240 W solar · 13 lb

Check price at Goal Zero → Full specs

EcoFlow RIVER 2 Max

512 Wh 500 W cont · 1,000 W surge ~12 h on this load $$

A half-kWh unit for CPAP, electronics, and a mini-fridge overnight.

LiFePO4 · ~1 h AC; up to 220 W solar · 13 lb

Check price at EcoFlow → Full specs

Jackery Explorer 500

518 Wh 500 W cont · 1,000 W surge ~12 h on this load $$

A long-running mid-small unit; NMC chemistry, so store it partly charged.

NMC · ~7.5 h AC; up to 100 W solar · 13 lb

Check price at Jackery → Full specs

Goal Zero Yeti 700

677 Wh 1,000 W cont · 1,500 W surge ~15 h on this load $$

Goal Zero’s LiFePO4 value unit — a 1,000 W inverter for fridge and essentials.

LiFePO4 · ~2.3 h AC; up to 200 W solar · 21 lb

Check price at Goal Zero → Full specs

Bluetti EB70Sstep-up

716 Wh 800 W cont · 1,400 W surge ~16 h on this load $$

A rugged 700 Wh workhorse for camping and outage essentials.

LiFePO4 · ~3.5 h AC; up to 200 W solar · 21 lb

Check price at Bluetti → Full specs

Bluetti AC70

768 Wh 1,000 W cont · 2,000 W surge ~17 h on this load $$

A 1,000 W inverter and 768 Wh — handles a fridge and most kitchen bursts.

LiFePO4 · ~45 min to 80% AC; up to 500 W solar · 23 lb

Check price at Bluetti → Full specs

🔗 The "Check price" buttons are brand-direct affiliate links. Once our brand affiliate programs are approved these will earn a commission — at no extra cost to you, and it never changes which unit we recommend. Disclosure.

The load, appliance by appliance

Appliance	Running	Surge	Duty
CPAP Machine (no humidifier)	40 W	—	100%	size on its own →

⚡ Informational only — a computed sizing estimate from published appliance-wattage charts and manufacturer station specs. It is not an electrical guarantee. For hardwired or whole-home backup, transfer switches, or any permanent install, consult a licensed electrician. Appliance wattages are representative chart values and vary by model; check your nameplates. Duty cycle (how much of the time a load actually draws) is how we keep the watt-hour estimate from overselling capacity.

Common questions

What size power station runs a CPAP all night?

For CPAP Machine (no humidifier) over 8.0 h, you need about 356 Wh of capacity, 40 W continuous output, and at least 40 W of surge. The smallest unit that clears all three is the Goal Zero Yeti 500X; a step-up like the Bluetti EB70S adds headroom for longer outages.

How many watt-hours does this load need?

About 356 Wh for 8.0 h — we take the duty-weighted average draw (40 W, since cyclic loads like fridges and pumps don't run constantly), multiply by the hours, and divide by a usable-capacity reserve. Running watts are 40 W; surge is 40 W.

Other scenarios

Power station for a home outage (fridge + CPAP + sump pump)

12 h

What size power station / battery backup for a sump pump?

6.0 h

What size power station / solar generator for van life?

12 h

What size power station runs a refrigerator in an outage?

24 h

What size power station runs a 1500 W space heater?

3.0 h

What size power station runs a window AC?

5.0 h

Sources: appliance wattages — standard appliance/generator sizing charts; station specs — manufacturer published specifications (compiled 2026-06-15; approximate). Informational only — a computed sizing estimate from published appliance-wattage charts and manufacturer station specs. It is not an electrical guarantee. For hardwired or whole-home backup, transfer switches, or any permanent install, consult a licensed electrician.