Backing up a CPAP with a power station
A CPAP is the single best case for battery backup: small, steady draw, and genuinely important that it keeps running. The arithmetic is easy — right up until you turn the humidifier on.
Before anything else
CPAP therapy is medical equipment. Follow the guidance from your device manufacturer and your clinician, not a website's arithmetic. If interrupted therapy is dangerous for you, do not rely on a single battery as your only contingency — and confirm with your equipment supplier that DC or battery operation is supported for your specific model. The numbers below are planning estimates calculated from published specifications; they are not a guarantee about your device.
Why the humidifier changes everything
A CPAP blower motor is a genuinely small load — most machines draw somewhere around 30 W running normal therapy pressures. That is less than a lightbulb, and it is why a power station handles it so well.
The humidifier is a different animal. Heating water, and heating the air in the hose, is resistive heating — and resistive heating is brutally expensive in battery terms. Switching both on typically takes a machine from about 30 W to about 90 W. You have tripled the load, so you have cut your runtime to a third:
Note how much the inverter's own 15 W standby draw costs you at this scale. Against a 30 W machine it is half again on top of the load itself — which is exactly why running the CPAP from the unit's 12 V DC output instead, where your machine supports it, buys back more runtime here than on any other load on this site.
Calculated nights, by unit
| Unit | Humidifier off ~30 W | Humidifier + heated hose ~90 W |
|---|---|---|
| Jackery Explorer 1000 v2 | 2.5 h nights | 1.1 h nights |
| EcoFlow DELTA 2 | 2.4 h nights | 1.0 h nights |
| BLUETTI AC180 | 2.7 h nights | 1.2 h nights |
Assumes an 8-hour night and typical draw figures; your machine's actual consumption depends on model, pressure setting and mask leak. Check your device's manual for its rated wattage and substitute it into the formula above.
Getting more nights out of the same battery
- Turn off the humidifier during an outage. This is the single biggest lever, worth roughly three times the runtime. A dry mouth for a few nights is a reasonable trade against therapy stopping entirely.
- Use the DC output if your machine supports it. Many CPAPs can run from 12 V directly. Doing so bypasses the AC inverter and its conversion loss, typically recovering 10–15% more runtime. Check your manual — and use the manufacturer's DC cable, not an improvised one.
- Skip the heated hose first. If you want some humidification, the hose heater is usually the larger of the two heating loads.
- Add a panel. A single 100 W panel in reasonable sun comfortably replaces a night of non-humidified CPAP use, which turns a three-night battery into an open-ended one.
Which unit suits this best
For CPAP specifically, capacity per pound matters less than you would think — you are not carrying it far, and even the smallest unit here covers multiple nights. Two things do matter:
- A quiet unit. These are all effectively silent under a 30 W load; fans generally do not spin up until the inverter is working much harder. That is the decisive advantage over a gas generator, which cannot run indoors at all.
- Pass-through charging. All three units here can be charged while simultaneously powering a device, so the power station can sit permanently plugged in beside the bed and take over the instant the grid drops.
The practical setup
Leave the power station plugged in at the bedside with the CPAP running from it permanently. Grid power keeps the battery topped up; when the power fails, therapy simply continues without you waking up. Any of the three units we cover does this.
Check today's price → Affiliate link — we may earn a commission at no extra cost to you. As an Amazon Associate I earn from qualifying purchases.For everything else you might want to keep running at the same time, the runtime reference has 20 loads calculated on the same basis, and the refrigerator guide handles the other load most households care about.
Questions people actually ask
How many nights will a 1000Wh power station run a CPAP?
About two nights with the humidifier off (roughly 19 hours of runtime at ~30 W), or about one night with the humidifier and heated hose running (~90 W). The calculation divides usable capacity — rated Wh × 0.85 for inverter conversion loss — by the machine's draw plus roughly 15 W of inverter standby consumption, which is significant when the load itself is only 30 W.
Does running a CPAP from DC instead of AC help?
Yes, typically by 10–15%. Running from the power station's 12 V DC output bypasses the inverter that converts DC to household AC, and that conversion is where roughly 15% of the energy goes. Check your machine's manual for DC support and use the manufacturer's own DC cable.
Is a power station quiet enough to sleep next to?
Under a load as small as a CPAP, yes — the cooling fans on these units generally do not engage until the inverter is working far harder than 30 W. This is the clear advantage over a gas generator, which produces both noise and carbon monoxide and cannot be run indoors under any circumstances.
Can I leave it plugged in all the time?
Yes, and that is the sensible setup. All three units support pass-through charging, so the CPAP runs from the power station while the power station stays connected to the grid. When the grid fails, the machine keeps running with no interruption and no intervention.