CPAP Battery Backup: How to Keep Your CPAP Running in a Power Outage

A CPAP battery backup lets you keep treating sleep apnea when the power goes out. For many people, a night without CPAP means poor sleep and a hard next day. For others, the stakes are higher. The good news is that most CPAP machines use relatively little power, so a well-chosen CPAP battery or portable power station can carry you through one or several nights. This guide explains how to plan backup power, size a battery and test it safely.

Last reviewed and updated: October 1, 2026. Written by Jeremy Jarvis.

This is general information, not medical advice. Your equipment supplier and care team know your machine and needs, so involve them in your plan.

Why plan CPAP battery backup before an outage

Outages tend to happen at night and during storms, when it is hardest to improvise. Stores may be closed, and roads may be unsafe. If you plan now, you can choose the right battery, get the correct cables and test everything while the lights are on. In addition, planning lets you ask your supplier the right questions before you need answers.

Ready.gov advises planning for medical devices that need electricity. The FDA likewise recommends checking whether your device can run on batteries or a generator, and for how long. A CPAP plan is a perfect example of that advice in action.

Start with your equipment supplier

Every CPAP model is different. Some manufacturers make dedicated batteries for their machines. Others offer DC cables or converters that connect to standard batteries or power stations. Your supplier can tell you which options your model supports and which settings are safe to change during an outage. They can also tell you whether your insurance covers any of it.

Ask these questions: What is the machine’s power draw with and without the humidifier? Does it accept DC input, and which cable or converter is approved? Are there settings I should not change? Write the answers down and keep them with your backup kit.

How much power does a CPAP use?

CPAP power use depends on the model, pressure setting, humidifier use and heated tubing. Without heated humidification, many machines draw only a few dozen watts on average. With the humidifier and heated tubing on, draw can rise substantially, because heating water and air takes far more energy than moving air. Higher pressure settings also raise draw a little.

Look for the power rating in your manual or on the power supply, but remember that the power supply rating is a maximum, not the average. The most accurate method is to measure. A plug-in energy meter between the outlet and the CPAP shows real watts and total watt-hours over a night. One night of measurement gives you the number you need for sizing.

The humidifier and heated tubing

The single biggest lever on runtime is humidification. Turning off the heated humidifier and heated tubing during an outage can multiply how long a battery lasts. Many people find they can sleep comfortably without humidification for a night or two, though some find their nose and throat get dry.

Ask your care team whether turning humidification off is acceptable for you. Some machines allow passive humidification, where the water chamber stays in place without heating. Meanwhile, keeping the bedroom warmer in winter can reduce condensation issues if you do use heated tubing on battery.

CPAP battery backup options

For most households, a portable power station with the manufacturer’s DC cable or converter is a strong choice. It runs the CPAP efficiently and can also charge phones and run a lamp. Our portable power station buying guide explains how to choose one.

Sizing a CPAP battery backup

Sizing is straightforward. Multiply your machine’s average watts by the hours you sleep. That gives watt-hours per night. Then add about 20 percent for converter losses and battery aging. Finally, multiply by the number of nights you want to cover without recharging.

For example, suppose your CPAP averages 40 watts without humidification and you sleep 8 hours. That is 320 watt-hours per night. With a 20 percent margin, plan for about 385 watt-hours. A mid-size power station with around 1,000 Wh usable could cover two to three nights, and more if you also turn down other loads. With humidification on, your nightly need could be several times higher. The Home Power Station Selector includes a CPAP line you can edit.

DC vs. AC power for a CPAP battery

CPAP machines run internally on DC power. Their wall adapter converts household AC to DC. When you run a CPAP from a power station’s AC outlet, the station first converts its battery’s DC power to AC, then the CPAP adapter converts it back to DC. Each conversion wastes some energy.

Using a DC cable or converter skips the AC step. As a result, the same battery often lasts noticeably longer. Use only the cable or converter your machine’s manufacturer approves, because voltage and connector details matter. If you must use AC, choose a power station with a pure sine wave inverter, which suits medical electronics.

The UPS feature for seamless backup

Some power stations offer a UPS-style mode. The CPAP stays plugged into the station, which passes grid power through. When the power fails, the station switches to battery quickly, often without interrupting the machine. That means you can sleep through an outage. Check the stated switchover time, and test it with your machine.

Recharging your CPAP battery during a long outage

If an outage lasts several days, you will need to recharge. Options include portable solar panels, a car’s 12-volt outlet and a generator. Solar is quiet and safe, but slow in winter or cloudy weather. Car charging works if the car runs outdoors, never in an attached garage. A generator must always run outdoors, away from windows, doors and vents.

Daytime recharging fits naturally with CPAP use, because the machine runs at night. Recharge the battery during the day, then run the CPAP overnight. Our solar generator guide explains realistic solar charging times.

Test your CPAP battery backup at home

Testing turns a plan into confidence. On a normal night, run your CPAP from the backup battery with the settings you would use in an outage. In the morning, note the remaining charge. That tells you how many nights you can count on. If the result is short, adjust settings or choose a larger battery.

Repeat the test before storm season and after any change to your machine or settings. Keep the battery charged between tests. Also, store the cables, converter and a printed copy of your supplier’s answers with the battery.

CPAP battery backup for winter and summer outages

Seasons change how you use your CPAP battery backup. In winter, a cold bedroom makes heated tubing tempting, but heating drains the battery quickly. Instead, keep the bedroom as warm as safely possible with blankets and layers, and run the machine without heat if your care team agrees. Cold also reduces battery performance, so store the power station indoors where it stays warm.

Summer outages bring a different problem: heat. A hot bedroom can make sleep difficult, and fans add to the load. A small DC fan uses little energy, so it can share the battery with the CPAP for a night. Meanwhile, keep the battery out of direct sun and away from heat sources, because high temperatures can trigger protective shutdowns.

Combining CPAP backup with home backup

If your home already has a generator or a whole-home battery, your CPAP can share that system. Even so, a separate CPAP battery backup in the bedroom adds a layer of protection. It covers the few seconds or minutes before a generator starts, and it keeps working if the larger system fails or runs out of fuel. Many households keep a small power station by the bed for this reason alone.

When the generator runs, you can recharge the bedroom battery during the day. Then, overnight, the CPAP runs quietly from the battery while the generator rests. This approach saves fuel and lets everyone sleep without engine noise. Our guide to choosing a generator for home use explains the larger system.

Building a CPAP outage kit

A simple kit saves time in the dark. Store the battery or power station, the DC cable or converter, a power meter, a flashlight, spare mask parts and a printed copy of your supplier’s guidance together in one bag. Keep the battery charged and check it monthly. Add a note with the number of nights your test showed, so anyone in the household knows what to expect.

Traveling with CPAP batteries

Many CPAP users also want battery power for camping or travel. If you fly, airlines have rules about lithium batteries, especially large ones. Check the airline and Transportation Security Administration rules before you pack. Smaller manufacturer CPAP batteries are often designed to meet travel limits, while large power stations usually are not allowed in airplane cabins.

Other preparation for CPAP users

The FDA advises notifying your electric company and fire department if you rely on a powered medical device. Many utilities keep a medical priority or notification list. In addition, keep a flashlight by the bed, a charged phone and a list of nearby places with power, such as a hospital or community center, in case an outage lasts longer than your battery.

Keep distilled water on hand if you use humidification when power returns. Finally, check that your mask and supplies are in good condition, because you may not be able to get replacements quickly after a storm.

Safety tips

Use batteries and power stations from reputable manufacturers with recognized safety certifications. Keep them dry, ventilated and away from heat. Never run a generator or a car indoors to charge equipment. Ready.gov advises keeping generators outdoors and at least 20 feet away from windows. If anyone in the home feels dizzy, headachy or nauseated during an outage, get to fresh air and call for help, because these can be signs of carbon monoxide poisoning.

CPAP battery backup checklist

• Ask your supplier about approved batteries, DC cables and settings.
• Measure your machine’s real watts for a full night.
• Decide whether you can turn off humidification during outages.
• Size the battery for the number of nights you want to cover.
• Use a DC connection where approved, or a pure sine wave AC outlet.
• Test the setup overnight and note the remaining charge.
• Plan daytime recharging with solar, a car or a generator outdoors.
• Tell your utility and fire department you use a powered medical device.

Where to compare CPAP backup options

When you know your nightly watt-hours, compare current power stations for CPAP and CPAP DC cables and converters that your machine’s manufacturer supports. Always confirm compatibility with your supplier. For broader outage planning, see our Outage Prep hub.

Frequently asked questions about CPAP battery backup

How long will a battery run a CPAP?

Divide the battery’s usable watt-hours by your machine’s average watts, allowing for converter or inverter losses. A CPAP without heated humidification often draws a few dozen watts, so a mid-size power station can often run it for several nights, while humidifier use shortens runtime a lot.

Can I run a CPAP on a portable power station?

Many people do. Check that the station’s output suits your machine, ideally use the manufacturer’s DC cable or converter, and test it overnight before an outage. Ask your equipment supplier which options are approved for your model.

What should I do with my CPAP during a power outage?

Switch to your planned battery backup, turn off heated humidification if your clinician agrees, and keep the battery charged during the day if you can. If you have no backup and depend on the device, contact your care team or seek a location with power.

Should I tell my utility that I use a CPAP?

The FDA advises notifying your electric company and fire department if you use a medical device that needs power. Many utilities keep a medical priority or notification list.

Is DC power better than AC for a CPAP battery?

Using the machine’s DC input, with the manufacturer’s DC cable or converter, avoids converting battery power to AC and back, which can waste energy. That usually means longer runtime from the same battery.

Sources and how we researched this guide

This guide is research-based and is not medical advice. We did not test CPAP machines or batteries; we summarize FDA and Ready.gov guidance on medical devices during outages and explain the runtime math used in our free Home Power Station Selector. Confirm battery options with your equipment supplier and care team. Found something out of date? Tell us and we will check it against the source.

• FDA: Tips about medical devices and natural disasters
• Ready.gov: Power outages
• American Red Cross: Power outage safety
• Ready.gov: Build a kit

Keep planning

• How Many Watts Does a Refrigerator Use? Running, Starting and Daily kWh
• What to Do During a Power Outage: A Calm, Step-by-Step Guide
• How Long Does Food Last in a Fridge Without Power? Safe Timelines
• Power Outage Emergency Kit: What to Pack and How to Keep It Ready

Go deeper: Outage Prep hub · Power Outage Checklist · Power Outage Food Safety Timer