Buyer's Handbook

Backup Power for Medical Devices

Keeping a CPAP, an oxygen concentrator, or another plug-in medical device going when the power goes out. What the device makers and federal agencies actually say, how each kind of backup works, how long it really lasts, and what to buy, if anything.

Reviewed October 2026. We re-check this guide quarterly.

Planning guidance, not medical advice. Every device has its own power rules. Confirm what your device can safely run on with its manufacturer, your home medical equipment supplier, and your prescriber before you rely on any backup.

Start here

The lights go out at bedtime, and one machine matters more than the rest

It is half past ten and the house goes dark. The refrigerator can wait and the phones are charged. The question is the CPAP on the nightstand, or the oxygen concentrator humming in the corner, which goes quiet with everything else. Some home concentrators, Inogen's At Home among them, sound a continuous alarm when they lose power, which is a good design and a hard sound to plan around at midnight.[16]

You are far from alone in this. A federal health data program run by HHS tracks more than 4.6 million Medicare beneficiaries who live independently and rely on electricity-dependent medical equipment or certain essential health care services.[2]

This handbook is about the hardware: batteries, power stations, uninterruptible power supplies, and generators, and what each can and cannot do for a device that needs a plug. For some households the answer is a single battery made by the device's own maker. For others the most important purchase is not a battery at all. Both answers are easier to reach on a calm afternoon than on a dark night.

Before you buy

Six questions about your device and your home

Answer these with the device and its manual in front of you. They decide what kind of backup you need, and how much of it.

1

Which devices in the house need a plug, and how many watts does each draw?

The number is on the device label, the power supply, or the specifications page of the manual. Write it down for each one.

2

Can the device safely pause, or must it keep running?

A therapy you use at night and a device that supports breathing around the clock are different problems. Your prescriber is the one to say which yours is.

3

What does the device maker allow it to run on?

Its own battery, a DC cable, an inverter, a generator. FDA's advice is to read the user instructions or call the distributor or maker to find out.[1]

4

How long do outages usually last where you live?

One night points to a battery. Several days points to a way of recharging it, or to a plan that does not depend on one.

5

If it is oxygen, what backup supply does your equipment provider recommend?

Concentrator makers tell owners to keep an alternate source of oxygen for power outages. That conversation comes before any battery purchase.

6

Might you need to leave home, or fly, with the device?

An evacuation, a stay with family, a trip. Weight and airline battery limits change which backup makes sense.

How it works

Four kinds of backup, and how each one runs out

Every product in this category is a store of energy, a way to make it, or a way to switch between the two. The size of the store is measured in watt-hours: a device drawing 50 watts for 10 hours uses 500 watt-hours. That one multiplication answers most of the questions in this guide.

Start with the federal advice, which is short. FDA tells households with a device that needs power to find out whether it can run on batteries or a generator, and to let the electric company and the fire department know the device is in the home.[1] The Red Cross adds: discuss a plan with your medical device providers, and consider both backup and non-power alternatives.[3]

A battery made for the device

CPAP makers sell, or approve, batteries and DC cables built for their machines. Running on DC skips the conversion to household current, and the maker has already done the compatibility work. They are sized for a night, not a week: ResMed's Power Station II holds 97 watt-hours and is rated for more than 8 hours at average settings, a figure ResMed says does not apply when heated humidification and heated tubing are in use.[14] The size has a second reason. FAA limits spare lithium-ion batteries in carry-on bags to 100 watt-hours each unless the airline approves larger ones, so a battery under that line is one you can fly with.[15]

A portable power station

A large rechargeable battery with household outlets, USB ports, and a 12-volt socket. Mid-size models hold about 1,000 watt-hours; Anker's SOLIX C1000, for example, lists 1,056.[25] That is several CPAP nights or a few hours of a home oxygen concentrator. It runs out when the battery does, and it refills from the wall, a car, or solar panels. Our portable power station handbook covers the category in depth.

An uninterruptible power supply

A UPS sits between the wall and the device and takes over within milliseconds when the power drops. CyberPower lists a typical transfer time of 4 milliseconds for one of its sine wave models.[22] It is built to bridge a flicker or carry a device for minutes to a few hours, not overnight, and as you will see below, consumer UPS makers draw a line at medical equipment.

A generator

A generator makes power for as long as it has fuel, which makes it the only option here that covers days on its own. It also makes carbon monoxide, so it lives outdoors, well away from the house, and it brings rules of its own. Those are covered in the section on covering several days.

Whatever you choose

Test it with the real device on an ordinary night. Every runtime in this category is a maker's figure measured at stated settings, and your pressure, your humidifier, your mask fit, and your room change the answer. One full night on the backup tells you more than any box.

The distinction that matters most

A battery is a bridge. For oxygen, the backup is oxygen.

Two devices dominate this category, and they sit at opposite ends of it. Put the makers' own numbers side by side and the difference is plain.

A CPAP for one night

About 450 Wh

ResMed lists a typical power consumption of 56.1 watts for the AirSense 11.[9] Eight hours at that draw is about 450 watt-hours, within reach of a mid-size power station. Turning off the humidifier and heated tube cuts it sharply, as the next section shows.

A home concentrator for one day

2,400 to 8,400 Wh

Philips lists an average of 350 watts for its EverFlo, which is 8,400 watt-hours across 24 hours.[18] Inogen lists 100 watts for its At Home model on flow setting 2, or 2,400 a day.[17] CAIRE lists 285 watts at 2 liters per minute for its Companion 5.[19] Your prescribed flow sets the real number.

What a 1,000 Wh station holds

Hours, not days

Run a 350-watt concentrator from a 1,056 watt-hour station and the arithmetic gives you about three hours before conversion losses, and less in practice. That is time to start a generator, switch to backup oxygen, or reach somewhere with power. It is not a night.

This is why concentrator makers put the backup in a tank, not a battery. Inogen recommends having an alternate source of oxygen available in case of a power outage or a mechanical failure, and tells owners to ask their equipment provider which backup system to use.[16] CAIRE's manual says patients should have a backup supplemental oxygen source in case the concentrator fails during a power outage.[20] A power station can still earn its place in an oxygen household. It shortens the gap. It does not replace the cylinder.

For a CPAP, a battery covers the whole problem for a night or two, which is why that end of the category is where most of the buying happens. For a ventilator or any device a prescriber says must never stop, the plan belongs to the prescriber and the equipment supplier first, and the purchase follows from it.

Safety: what no backup can do

  • It cannot stand in for backup oxygen. The concentrator makers above call for an alternate oxygen source for outages. Arrange it with your equipment provider before you shop for batteries.[16][20]
  • It cannot make a generator safe indoors. CDC says never to use a generator inside your home or garage, even with doors and windows open, and to run it outside, more than 20 feet from windows, doors, and vents.[4]
  • It cannot make candles safe near oxygen. FDA says to use battery-powered flashlights or lanterns rather than gas lights or torches when oxygen is in use, and NFPA says to avoid candles and other open flames wherever medical oxygen is used.[1][8]
  • It cannot tell you your device is compatible. Only the device maker or your supplier can confirm what your device may run on. FDA's advice is to read the user instructions or call them.[1]
  • It is not a reason to stay. The Red Cross lists having medical devices that need power among the reasons to evacuate during an outage.[3] Decide where you would go before the outage, not during it.

Reading the label

What the numbers promise, and what the fine print says

Four numbers decide whether a backup fits your device. Then there is a fifth thing to read, in the manual rather than on the box, and it surprises most buyers.

The draw, at your settings

A power supply's rating is a ceiling, not a typical draw. The AirSense 11 ships with a 65-watt power supply, lists 56.1 watts as typical and 73.2 as peak.[9] Plan on the typical figure and leave room for the peak.

The humidifier

On a CPAP it is usually the biggest load. ResMed's power sheet for the AirSense 10 lists 7 watt-hours for the machine alone, 22 with the humidifier, and 34 with the humidifier and heated tube, at its stated test settings.[10] Ask your prescriber whether a night without heat is acceptable for you.

The waveform

An inverter turns stored DC into household AC. A pure sine wave inverter produces the same waveform as a household outlet, in ResMed's words.[12] Cheaper ones produce a stepped or simulated wave; APC says its Back-UPS models do this on battery, and CyberPower sells separate simulated and pure sine wave lines.[21][22]

The switchover time

How fast a backup takes over when the wall goes dead. CyberPower lists 4 milliseconds for a sine wave UPS; Anker and Jackery list under 20 milliseconds for their power stations.[22][25][23]

Pure sine wave is a safe default, not a universal rule

You will read that every CPAP needs a pure sine wave inverter. ResMed's own guidance is more specific. For the AirMini, AirSense 10, AirCurve 10, Lumis, and S9, ResMed says a modified sine wave inverter with a continuous rating of 150 watts or more will do, and that older machines with H2i, H3i, or H4i humidifiers need a pure sine wave inverter rated 300 watts continuous and 500 watts peak.[11]

We did not find a published ResMed statement either way for the AirSense 11. The practical answer: buy pure sine wave, which matches the wall, and confirm with your device maker. That removes the question instead of guessing at it.

Flying with a battery

FAA limits lithium-ion batteries to 100 watt-hours each, allows up to two spares between 101 and 160 watt-hours with airline approval, and requires spares to travel in carry-on bags only.[15]

A portable power station is far above those limits. If travel is part of your plan, a device battery under 100 watt-hours is the one that goes with you.

The fine print most buyers miss

What the power makers say about medical devices

Power station marketing often mentions CPAP. The manuals and support pages are more careful, and they are worth reading before you buy.

  • Jackery says on its Explorer 1000 v2 page that its power stations are not recommended for use with medical devices, life-support equipment, or other uses where an interruption could cause injury, and that people with an implanted pacemaker or other implanted medical device are advised not to use the product.[23]
  • EcoFlow says in its DELTA 3 Max Plus manual that the product is not intended for life-sustaining medical equipment, naming medical-grade ventilators and hospital-grade CPAP, and that for other medical equipment you should check with the equipment's maker first. It also warns that the unit's electromagnetic fields may affect pacemakers and other implants.[24]
  • CyberPower lists medical equipment among the things that void its UPS warranty.[22]
  • Oxygen concentrator makers are wary of the cord itself. Inogen says to avoid extension cords with its At Home concentrator, and CAIRE says not to connect its adapter to a power strip.[16][20] A power station's outlet is not an extension cord, but ask your supplier how your model should be connected to any backup.

None of this means a power station cannot run your CPAP. Many people do exactly that. It means the device maker's approval is the one that counts, and the battery maker has told you, in writing, that the decision is not theirs to make.

Covering several days

A battery needs a way to fill back up

One night is a battery problem. Three nights is a recharging problem. There are three ways to solve it, and one of them comes with rules that are not optional.

Quiet

Solar panels

Folding panels refill a power station by day for use at night. Output depends on the panel, the season, and the sky, so test yours in your own yard before counting on it.

Mobile

A car

ResMed's DC converter lets a CPAP run from a 12- or 24-volt vehicle socket, and ResMed warns there may not be enough charge left to start the vehicle afterward.[13] Running the engine to recharge brings the same exhaust danger as a generator: outdoors only, never in a garage.[1]

Longest

A generator

The one option that keeps up with a concentrator for days, as long as fuel lasts. It can recharge a power station too, so the station runs indoors and the generator stays outside.

If a generator is part of the plan

  • Outside, and far enough. More than 20 feet from windows, doors, and vents, never in a garage, crawlspace, or shed, even with doors open.[4][5]
  • A CO alarm inside. CDC says to use a battery-powered or battery-backup CO detector whenever a generator is running.[4]
  • A shut-off feature. CPSC recommends looking for portable generators with a carbon monoxide shut-off safety feature, which turns the engine off when CO builds up around it.[6]
  • Never into a wall outlet. CPSC calls plugging a generator into house wiring backfeeding and warns that it puts utility workers and neighbors at risk of electrocution.[5] OSHA says to connect a generator to a building's wiring only through a transfer switch installed by a qualified electrician.[7]
  • The right cord. Heavy-duty extension cords made for outdoor use, each rated above the total wattage on it, per CPSC.[5]
  • Cool before fuel. Turn it off and let it cool before refueling.[5]

Our generator safety guide for medical households goes further, and the generators handbook covers choosing one.

What fails and why

The usual ways a good plan comes up short

A battery that aged in the closet

ResMed says its Power Station II runs about 60 percent as long after 500 recharge cycles, and that it must be recharged to full after six months of storage.[14] EcoFlow tells owners to charge and discharge its stations once every three months in long storage.[24] Put the date on your calendar.

The humidifier left on

By ResMed's figures above, the heated humidifier and tube can use several times what the machine itself draws. A battery sized with heat off and run with heat on comes up short in the small hours.

Settings that reset

FDA notes that many medical devices return to a default mode when power is interrupted, and says to check the settings once power is restored.[1]

A wet cord after a storm

FDA says not to plug in a power cord if the cord or the device is wet, and to check cords and batteries for water damage.[1]

A bargain battery

In 2025 CPSC warned consumers to stop using one brand of power station sold on Amazon because its battery could explode and ignite.[26] Buy from a maker you can look up, and check CPSC's recall list before you buy.

A plan nobody tested

The cable that does not fit, the alarm nobody recognized, the runtime that was half the box. All of it shows up on a test night, and none of it should show up for the first time during a storm.

What to buy

Now that you know what to look for

Below is the shortlist of requirements for each kind of backup, the same checks we use when we compare them. Our comparison of CPAP batteries is in progress; the related comparisons we have already published are linked below.

Affiliate disclosure: New World Survival earns a small commission on qualifying Amazon purchases at no cost to you. This helps us cover operating costs and keep building new content. We only recommend gear we would put in our own kit. Commission never decides a recommendation.

Device battery

  • Made or approved by your device's maker for your exact model
  • Runtime stated at stated settings, with and without heat
  • Under 100 Wh if you will fly with it
  • A charge-level check you can read

Power station

  • Pure sine wave AC output, stated on the spec sheet
  • Watt-hours sized to your device's real draw, with margin
  • A 12-volt socket if your device has a DC cable
  • Solar or car recharging if outages run long
  • A maker with a support line and no open CPSC warning

UPS

  • Pure sine wave on battery, not simulated
  • A transfer time in milliseconds on the spec sheet
  • Read the warranty terms for medical equipment first
  • A bridge for minutes, paired with something larger

Generator

  • A carbon monoxide shut-off feature
  • A place to run it more than 20 feet from the house
  • A battery-backed CO alarm inside
  • A transfer switch by an electrician, if it will feed house wiring

Comparison

Best Portable Power Station

Real-world watt-hours and the right size for most households, including CPAP nights.

Comparison

Best UPS Battery Backup

Pure sine wave, runtime, and the two jobs a UPS should do in a prepared household.

Comparison

Best Inverter Generator

Quieter, cleaner power for essentials over several days.

Comparison

CO Detectors

Certified carbon monoxide alarms for every sleeping area, and the one to add before any generator runs.

After you buy

The plan around the battery

A backup is one piece of keeping a device running. These guides cover the rest, from the sizing math to the call you make to your utility.

Power Outage Planning for Medical Devices

The four planning steps, starting with the wattage on your device's label.

Backup Batteries and Portable Power

Sizing a backup for each device in the house, and running the test night.

Utility Medical Programs

The medical registry your electric company may keep, and how to get on it.

When to Relocate

Setting the point at which you leave for somewhere with power, before the outage.

Generator Safety for Medical Households

Placement, carbon monoxide, and running a generator around medical equipment.

Printable Medical Device Power Plan

One page for each device's wattage, daily hours, and backup source. Keep a copy with the battery.

All comparisons

Every comparison, in one place

Each comparison we publish for medical device backup power is listed here as it is finished, starting with CPAP batteries. Until then, the related comparisons above cover power stations, UPS units, generators, and CO alarms.

Sources

  1. U.S. Food and Drug Administration. "FDA Offers Tips about Medical Devices and Natural Disasters." Content current as of April 16, 2024. Accessed October 7, 2026. fda.gov
  2. U.S. Department of Health and Human Services, Administration for Strategic Preparedness and Response. Program home page on at-risk, electricity-dependent Medicare beneficiaries. Accessed October 7, 2026. empowerprogram.hhs.gov
  3. American Red Cross. "Power Outage." Accessed October 7, 2026. redcross.org
  4. Centers for Disease Control and Prevention. "Carbon Monoxide Poisoning Basics." Last reviewed January 12, 2026. Accessed October 7, 2026. cdc.gov
  5. U.S. Consumer Product Safety Commission. "Portable Generator Hazards" Safety Alert, Publication 5123. Accessed October 7, 2026. cpsc.gov
  6. U.S. Consumer Product Safety Commission. "CPSC Warns of Generator Carbon Monoxide and Fire Hazards Ahead of Hurricane Season." News release, May 27, 2026. Accessed October 7, 2026. cpsc.gov
  7. Occupational Safety and Health Administration. "Using Portable Generators Safely." Fact sheet OSHA 3286, September 2005. Accessed October 7, 2026. osha.gov
  8. National Fire Protection Association. "Educational Messages Desk Reference," 2026 edition, chapter 18, Medical Oxygen. Accessed October 7, 2026. nfpa.org
  9. ResMed. "AirSense 11 User Guide" (document 398181, Australia and New Zealand edition), technical specifications. Accessed October 7, 2026. resmed.com
  10. ResMed. "Power Consumption: Air10 Devices" (document 1018673/1, March 2015). Accessed October 7, 2026. resmed.com
  11. ResMed Australia. "I am going camping. What do I need to run my sleep apnea machine?" Accessed October 7, 2026. resmed.com.au
  12. ResMed. "Battery Guide" (document 198103/4, August 2015). Accessed October 7, 2026. resmed.com
  13. ResMed. "Air10 / S9 DC/DC Converter 90W User Guide." Accessed October 7, 2026. resmed.com
  14. ResMed. "Power Station II User Guide" (document 248755/1, November 2014). Copy hosted by a retailer, thecpapshop.com. Accessed October 7, 2026. thecpapshop.com
  15. Federal Aviation Administration. "PackSafe: Batteries, Lithium Ion and Lithium Metal." Last updated August 11, 2026. Accessed October 7, 2026. faa.gov
  16. Inogen. "Inogen At Home User Manual" (2022). Accessed October 7, 2026. inogen.com
  17. Inogen. "Inogen At Home" product page. Accessed October 7, 2026. inogen.com
  18. Philips. "EverFlo Home Oxygen System" specifications. Accessed October 7, 2026. philips.com.au
  19. CAIRE. "Companion 5" specification sheet (ML-CONC0173 D). Accessed October 7, 2026. caireinc.com
  20. CAIRE. "HomeStyle Aspen User Manual" (MN273 D, December 3, 2025). Accessed October 7, 2026. caireinc.com
  21. Schneider Electric (APC). "Different Types of Voltmeters." FAQ FA158838, on Back-UPS output waveforms, modified May 19, 2026. Accessed October 7, 2026. se.com
  22. CyberPower Systems. "CP1500PFCLCD PFC Sinewave UPS" product page and FAQ. Accessed October 7, 2026. cyberpowersystems.com
  23. Jackery. "Explorer 1000 v2" product page and FAQ. Accessed October 7, 2026. jackery.com
  24. EcoFlow. "DELTA 3 Max Plus Portable Power Station User Manual." Copy hosted by a retailer, solarpowersupply.eu. Accessed October 7, 2026. solarpowersupply.eu
  25. Anker SOLIX. "C1000 Portable Power Station" product page. Accessed October 7, 2026. ankersolix.com
  26. U.S. Consumer Product Safety Commission. "CPSC Warns Consumers to Immediately Stop Using Aeiusny Power Stations Due to Risk of Serious Injury or Death from Fire; Sold on Amazon." Warning, September 4, 2025. Accessed October 7, 2026. cpsc.gov

We re-check this guide every quarter as guidance and products change. The Weekly Readiness Brief is a quiet way to hear when it updates.