- Medical devices require a pure sine wave inverter - verify before purchasing any power station
- CPAP without humidifier: 120–240 Wh per night. With heated humidifier: 240–520 Wh per night
- Stationary home oxygen concentrators need 6,000–8,400 Wh a day - a portable station is a few-hour bridge, not a 24-hour plan
- EcoFlow Delta units switch over in under 30ms, fast enough for most devices, but it is not a true zero-transfer UPS, so test your device first
- Contact your device manufacturer for official backup power compatibility before purchasing
A CPAP without a heated humidifier needs 120-240Wh for one 8-hour night. With the humidifier on, 240-520Wh. A portable oxygen concentrator needs about 480-960Wh over an 8-hour night; a stationary 5 LPM home unit needs 6,000-8,400Wh a day. All major power stations use pure sine wave inverters compatible with medical equipment. Enable UPS mode for automatic switchover.
How Long Will a Portable Power Station Run a CPAP Machine?
A CPAP without a heated humidifier draws 15–30W, which works out to 120–240Wh over an 8-hour night. A 500Wh power station gives you roughly two to three nights on that basis. Turn the heated humidifier and heated tube on and draw rises to 30–65W, or 240–520Wh a night, which cuts the same station to about one night. Disable the humidifier during outages to maximize runtime. Specific draw varies by CPAP model and pressure setting, so measure yours with a plug-in watt meter for a real number.
Best Portable Power Station for Medical Devices
For medical device backup, prioritize three features: UPS mode for automatic switchover, pure sine wave output for sensitive electronics, and LiFePO4 chemistry for long-term reliability. The EcoFlow Delta 3 and Jackery Explorer 1000 Plus both offer all three. Portable oxygen concentrators draw 60–120W, so a 2,000Wh station covers roughly 14 to 28 hours of pulse-dose use. Stationary 5 LPM units are a different problem: at 250–350W continuous they consume 6,000–8,400Wh a day, which is past what any single portable station covers - read the oxygen section below before you size anything.
Why Medical Device Backup Power Is Different
Backup power for a medical device is not optional preparation. For someone who uses a CPAP machine, oxygen concentrator, or home dialysis equipment, a power outage that lasts more than a few hours becomes a genuine health risk. The stakes are different, and the research needed to make the right decision is different too.
Most portable power station reviews treat CPAP as an afterthought — a bullet point in a list of things you can plug in. This guide is built specifically around medical device users, with actual watt-hour draw figures, runtime calculations by specific device model, and recommendations for people who cannot afford to guess wrong.
This guide provides technical information about power requirements for medical devices. It is not medical advice. Before changing your power backup setup for a life-critical medical device, consult with your physician and the device manufacturer. Some devices have specific requirements for backup power compatibility that may differ from what we describe here.
CPAP Machine Power Requirements
The first thing most people get wrong about CPAP power backup is the draw estimate. Manufacturer specifications often give a maximum wattage that overstates typical consumption. Real-world draw depends on your prescribed pressure setting, whether you use a humidifier, and which specific machine you have.
Here are typical draw ranges for common CPAP machines at typical pressure settings. Treat them as estimates and measure your own machine with a plug-in watt meter:
| CPAP Machine | Without Humidifier | With Humidifier | Per Night (8 hrs) |
|---|---|---|---|
| ResMed AirSense 10/11 | 15–30W | 30–55W | 120–440 Wh |
| Philips DreamStation 2 (new units not sold in the US since 2024) | 15–30W | 30–65W | 120–520 Wh |
| ResMed AirMini (travel) | 10–20W | N/A (no humidifier) | 80–160 Wh |
| Fisher & Paykel SleepStyle | 15–30W | 30–65W | 120–520 Wh |
| Lowenstein Prisma (BiPAP) | 40–80W | 60–100W | 320–800 Wh |
The range within each machine reflects differences in prescribed pressure settings. Higher pressure requires more motor work, which draws more power. If you're on a higher pressure setting (above 12 cm H2O), use the higher end of the range for your calculations. If you're on a lower setting (below 8 cm H2O), the lower end is more accurate.
The Humidifier Problem
The heated humidifier that ships with most modern CPAP machines is the single biggest variable in power consumption. Heating water takes significant energy — often more than the machine itself. As the table shows, adding a humidifier can more than double your CPAP's power draw.
If you're planning for power outages, this is worth thinking through: most CPAP users can tolerate using their machine without the humidifier for one or two nights. Turning off the humidifier during an outage dramatically extends your battery runtime. Some machines have a passover humidifier option that uses no power but still provides some moisture.
For the purpose of sizing your backup system, calculate based on your normal use including humidifier, but know that disabling it is a runtime extension option if needed.
How Many Nights Can You Get?
Using the ResMed AirSense 10 as a representative example at mid-range pressure with humidifier (45W average, approximately 360 Wh per night), here's what different power stations deliver:
| Power Station | Usable Capacity | Nights (with humidifier) | Nights (without humidifier) |
|---|---|---|---|
| Jackery Explorer 500 v2 (512 Wh) | ~435 Wh | 1.2 nights | 2–3.5 nights |
| EcoFlow River 3 Plus (286 Wh) | ~245 Wh | 0.7 nights | 1–2 nights |
| EcoFlow Delta 3 (1,024 Wh) | ~870 Wh | 2.4 nights | 3.5–7 nights |
| Jackery Explorer 1000 Plus (1,264 Wh) | ~1,075 Wh | 3 nights | 4.5–9 nights |
| Jackery Explorer 1000 v2 (1,070 Wh) | ~910 Wh | 2.5 nights | 4–7.5 nights |
| EcoFlow Delta 2 Max (2,048 Wh) | ~1,740 Wh | 4.8 nights | 7–14 nights |
For most CPAP users planning for 2–3 day outages, the EcoFlow Delta 3 or Jackery 1000 Plus hit the sweet spot of capacity, portability, and price. If you're in a hurricane zone where week-long outages are possible, the Delta 2 Max provides meaningful margin.
Many CPAP machines can run directly from DC power through the manufacturer's own DC converter, sold separately. Use the manufacturer's DC converter for your exact model: ResMed, for example, sells one converter for the AirSense 10 and a different one for the AirSense 11, and a generic barrel cable should not be assumed to work. Running on DC skips the power station's AC inverter and its conversion loss, which can noticeably extend runtime on a smaller station. Check your machine's manual or the manufacturer's website for the correct part.
Oxygen Concentrators: A Different Scale
Home oxygen concentrators have substantially higher power requirements than CPAP machines, and the math changes the system you need significantly.
A typical 5-liter-per-minute home oxygen concentrator draws 250–350 watts continuously. At 300W average over 24 hours, that's 7,200 Wh per day, roughly four to six times what a full-size refrigerator uses in a day. For a 24-hour outage, you need approximately 7.2 kWh of usable battery capacity, which is beyond what any single portable power station delivers - that is whole-home battery or generator territory. Even a single 8-hour night at 350W needs about 2,800Wh of usable energy, which means a station rated roughly 3,300Wh once inverter losses are counted. Our home oxygen concentrator backup guide walks through the overnight math and the winter-outage case in detail.
| Device Type | Typical Draw | Daily Consumption | Min. System Size for 24 hrs |
|---|---|---|---|
| CPAP (no humidifier) | 15–30W (8 hrs) | 120–240 Wh | 500 Wh |
| CPAP with humidifier | 30–65W (8 hrs) | 240–520 Wh | 1,000 Wh |
| BiPAP / ASV | 40–100W (8 hrs) | 320–800 Wh | 1,500 Wh |
| Portable O2 Concentrator (1–3 LPM) | 60–120W | 1,440–2,880 Wh | 3,500 Wh |
| Home O2 Concentrator (5 LPM) | 250–350W | 6,000–8,400 Wh | Whole-home system |
| Home Dialysis (NxStage) | 200–400W (4–6 hrs) | 800–2,400 Wh | 3,000+ Wh |
A standard portable power station is not a reliable long-term backup for a continuous-use home oxygen concentrator. The power demand is simply too high. Users who depend on home oxygen should work with their physician and equipment supplier to establish a formal emergency power plan, which may include a liquid oxygen backup cylinder, a medical-grade generator, or a whole-home battery system. A portable power station can serve as a bridge for a few hours but should not be your primary plan.
Recommended Power Stations for Medical Device Users
The Delta 3 is our top recommendation for CPAP users planning for standard 1–3 day outages. At 1,024 Wh with pure sine wave output, it handles any CPAP machine reliably, and fast AC recharging (about an hour from the wall) means even a brief return of grid power can meaningfully extend your runtime. Its EPS mode switches over in under 30ms, fast enough for most devices, but it is not a true zero-transfer UPS, so test your device first. For longer runtime on DC, use your CPAP manufacturer's DC converter for your exact model.
The 1000 Plus's 1,264 Wh capacity gives you roughly three nights with a humidifier, or about four to nine without. It is also expandable: you can add up to three Jackery battery packs, for about 5kWh in total, without buying a new unit. The unit supports solar input up to 800W, so in a longer outage you can recharge it from solar during the day.
BiPAP and ASV users draw significantly more power than standard CPAP users. The Delta 2 Max's 2,048 Wh capacity and 2,400W output handle high-pressure BiPAP while also running other household essentials. For households with more than one CPAP or BiPAP user, it provides enough headroom to cover several nights without constant rationing. It is not sized to run a stationary home oxygen concentrator through the night; see the oxygen section above.
What to Look for Beyond Capacity
For medical device applications specifically, these features matter beyond just watt-hours and output wattage:
Pure Sine Wave Output (Non-Negotiable)
Medical devices with electronic controls — CPAP pressure regulators, oxygen concentrator compressors, dialysis pumps — require clean, stable AC power. Modified sine wave inverters can cause erratic device behavior, overheating, and in some cases damage internal components. Every power station we recommend uses pure sine wave output. Never use a modified sine wave unit for medical devices.
UPS / EPS Mode
Some power stations include a UPS (Uninterruptible Power Supply) mode that switches to battery power within milliseconds of detecting a grid failure. This matters for CPAP users because some machines will reset their session data or require manual restart after a power interruption. Look for a unit with less than 30ms switchover time for CPAP applications.
EcoFlow units typically switch in under 30ms. Jackery's newer models advertise similar performance. Bluetti's switchover varies by model — check the specific model's spec sheet.
Cold Weather Performance
LiFePO4 batteries lose capacity in cold temperatures — typically 20–30% capacity loss at freezing temperatures. If you're in a winter storm scenario where power is out and the house is getting cold, your actual available capacity may be lower than the rated figure. Size with this in mind if you're in a northern climate.
Setting Up Your Medical Device Backup Plan
A power station is one component of a complete medical backup plan. Here are the additional steps worth taking:
- Register with your utility as a medical necessity household. Most utility companies have programs for households with life-sustaining equipment. Registration can mean priority restoration and advance notice of planned outages.
- Contact your equipment supplier. Many DME (durable medical equipment) suppliers have emergency protocols for customers who use life-sustaining devices, including loaner equipment and emergency service lines.
- Keep your power station charged. A power station that's been sitting at 20% charge for six months won't help you. Most manufacturers recommend storing LiFePO4 batteries at 50–80% charge and checking monthly.
- Test the connection before you need it. Plug your device into the power station during normal conditions and confirm it operates correctly. Some devices have compatibility quirks that are easier to troubleshoot when there's no emergency.
- Have a backup plan for the backup plan. A second, smaller power station as a supplemental reserve, or a DC power bank if your device supports it, adds resilience to any outage scenario.
The Lightweight Option: EcoFlow River 3 Plus
For CPAP travelers specifically, weight matters as much as runtime. The EcoFlow River 3 Plus weighs about 10.4 lbs with 286Wh of LiFePO4 capacity, enough for roughly one to two nights of CPAP use with the humidifier off. No power station of this size can fly: US rules forbid lithium batteries over 160Wh on passenger aircraft, so plan to keep it in your car or at your destination, and ask your CPAP maker about an approved travel battery if you need power on the plane.
286Wh in about 10.4 lbs with pure sine wave output and LiFePO4 cells rated for 3,000 cycles to 80%. Roughly one to two nights of CPAP with the humidifier off, and expandable to 858Wh with an EcoFlow extra battery. At 286Wh it is over the 160Wh limit for passenger aircraft, so it cannot go in carry-on or checked bags.
Complete Your Setup
The add-ons most people wish they'd bought at the same time. Honest picks, matched to this setup.
Frequently Asked Questions
Can a portable power station run my CPAP all night?
Yes. Most CPAPs draw modest wattage, so a mid-size pure sine wave station typically covers a full 7 to 8 hour night on one charge, often several nights. Runtime drops sharply with the heated humidifier and heated tube, so turning heated humidification off is the biggest way to stretch it.
Do I need a pure sine wave power station for medical devices?
Yes. Sensitive electronics like CPAPs, oxygen concentrators, and nebulizers can run erratically or throw errors on modified sine wave. Nearly all reputable LiFePO4 stations are pure sine wave, but confirm it in the spec sheet before buying.
How do I figure out how many nights my CPAP will run off a battery?
Measure your real draw with a plug-in watt meter over one night, then divide the station's usable watt-hours by that nightly figure. Running the CPAP on DC through a car or DC cable instead of the AC inverter avoids conversion loss and adds meaningful runtime.
Can a portable power station run a CPAP machine?
Yes. A CPAP without a heated humidifier draws 15-30W, so a 300Wh station covers a full 8-hour night with margin. With the heated humidifier and heated tube on, draw rises to 30-65W and you need roughly 240-520Wh for one night. All reputable power stations use pure sine wave inverters compatible with CPAP motors.
How long can a power station run an oxygen concentrator?
It depends on the type. A portable pulse-dose concentrator draws 60-120W, so a 2,000Wh station runs one for roughly 14 to 28 hours. A stationary 5 LPM home unit draws 250-350W continuously, so the same station lasts about 5 to 7 hours and cannot cover a full day. Oxygen concentrators are life-critical equipment - always have a backup plan and contact your equipment provider for official battery backup guidance.
Do medical devices need pure sine wave power?
Yes. Medical devices are designed for the clean sine wave that comes from the grid. Modified sine wave power can cause device controllers to behave erratically, run equipment hotter, or trigger error states. All major portable power station brands (EcoFlow, Jackery, Bluetti) use pure sine wave inverters.
What is the fastest UPS switchover time for medical devices?
EcoFlow specifies EPS switchover in under 30ms on its Delta series, fast enough for most devices, but it is not a true zero-transfer UPS, so test your device first. For CPAP use, under 30ms is generally enough, but treat a power station's EPS as basic backup rather than a true zero-transfer UPS for critical medical equipment.