Knowledge Base

How Many Watts Does a CPAP Use? (Power Consumption Test)

By:Michael Johns

cpap power header

On this page, you will find out how many watts a CPAP draws.

It can be difficult to sleep without your CPAP machine. The improved airflow gives you a more restful night so you wake up feeling 100%. Plus there are numerous other benefits that reduce illness and disease. Many people suffer when going camping or on vacation as they struggle to run their equipment correctly.

Knowing the power consumption helps you to find batteries, adapters, and power stations to keep you breathing easy when away from home. In addition, you can work out the electricity used every night.

Below we will discuss and test CPAP wattage, explain how to work it out for yourself, and calculate the total electricity required.

How Many Watts is a CPAP?

The average CPAP uses between 20 – 70 watts. In addition, CPAP machines have a peak wattage of about 100 watts. This peak power surge lasts for 1 or 2 seconds when you first switch the device on.

The exact number depends on the size and model of your CPAP. The newest devices are very compact and efficient these days. You find the average power consumption is less than 30W. Older machines are not so efficient and tend to draw a little more power around 50W. 

How to Find Out Your CPAP Wattage

There are 3 ways you can work out the wattage of a CPAP.

  1. Check Product Specification

The quickest way is to look at the CPAP’s specification. The watts (W) is usually written on a sticker on the base of the appliance. If not, you can check the user manual or the manufacturer’s website for technical details.

  1. Use a Wattmeter

A wattmeter is brilliant for getting a live wattage reading and tracking total energy usage of any appliance. You can plug it into your CPAP to get instant information. 

  1. Wattage Formula or Calculator

If you know the amperage and voltage of your CPAP you can use this to find the maximum watt rating. Simply use the formula Amps x Volts = Watts. Or you can head over to the ‘Watt Calculator’ to work this out.

CPAP Wattage Examples

Let’s take a look at specific examples of how many watts a CPAP draws. Below is a collection of modern CPAPs with their listed power ratings.

CPAP ModelPower Consumption (Watts)
ResMed AirCurve 10 V Auto 53
ResMed AirCurve 10 S Auto BiLevel53
Philips Respironics DreamStation Auto CPAP Machine80
Resmed Airsense 1024

As you can see, the power ratings vary between different CPAPs. So you should take the time to check your own appliance.

How Much Electricity Does a CPAP Use?

You can use CPAP wattage to work out how much electricity it uses. Plus this can be useful in understanding how much it costs to run your CPAP.

A watt (W) is a measurement of power at a single point in time. A watt-hour (Wh) is the total amount of electricity used in an hour. For example, a CPAP drawing 30W would use 30Wh when running for an hour.

Happily, electricity bills are recorded in kilowatt-hours (kWh). A kilowatt is simply 1000 watts. So a 30W CPAP running for 1 hour uses 0.03kWh.

In reality, you use a CPAP for 8 hours a night. This means a CPAP uses about 240Wh or 0.24kWh electricity a night. That’s 7.2kWh a month and 87.6kWh a year. 

That’s a rough electricity cost of $0.036 a night or $13.14 a year to power a CPAP machine for 8 hours a night.

Using a CPAP Off-Grid

If you’re planning to use your CPAP in an off-grid situation like a power outage, RV, boat, camping or similar, the information above is important. You can choose the correct electrical equipment and check if the runtime is sufficient.

You can either use a power inverter, portable power station, or generator to generate AC electricity. 

To make sure everything runs smoothly you should check two things on this equipment – wattage capacity and total energy capacity. 

Your power source, like an inverter, should have a wattage output of at least 20% more than your CPAP. This ensures it will be able to deliver enough power as they are never 100% efficient. 

Secondly, you need to ensure your energy source, like a battery, has enough energy to run the CPAP for the required amount of time. As we already know, it will use about 240Wh electricity each night. This is the equivalent to 20Ah on a 12V battery.

How Many Watts Does a CPAP Use Summary

I hope you now have a clear understanding of how many watts a CPAP uses.

The good news is that a CPAP uses very small amounts of power. Even running it every single night won’t impact your utility bills too heavily. It’s certainly an efficient way to get a good night’s sleep. Adding to this, you can easily run your machine in situations like camping. All you need is a decent portable power station that can supply at least 240Wh battery and 100W power output!