How much does it cost to run a CPAP per year?
About $4 a year without humidification and about $21 with it, at the US average of roughly 18 cents per kWh. A CPAP uses around 23 kWh a year dry, or around 117 kWh humidified — less than a single old incandescent bulb left on.
Power-draw figures for the machines below are provisional estimates, not yet our own meter readings. See how we test.
This one surprises people in the good direction. A CPAP feels like a significant appliance because it runs all night, every night — but 8W all night is less energy than a laptop charger, and the bill reflects that.
Annual consumption by machine
Eight hours a night, 365 nights, at a typical therapy pressure:
| Machine | Dry | Humidified |
|---|---|---|
| ResMed AirSense 11 | 23.4 kWh | 116.8 kWh |
| ResMed AirSense 10 | 26.3 kWh | 131.4 kWh |
| Philips DreamStation 2 | 26.3 kWh | 122.6 kWh |
| ResMed AirCurve 10 (BiPAP) | 35.0 kWh | 146.0 kWh |
| ResMed AirMini (travel) | 17.5 kWh | 17.5 kWh |
What that costs, by tariff
For an AirSense 11, the most common machine:
| Electricity rate | Dry | Humidified |
|---|---|---|
| $0.12 / kWh | $2.80 | $14.02 |
| $0.15 / kWh | $3.50 | $17.52 |
| $0.18 / kWh (US average) | $4.20 | $21.02 |
| $0.21 / kWh | $4.91 | $24.53 |
| $0.25 / kWh | $5.84 | $29.20 |
| $0.30 / kWh | $7.01 | $35.04 |
The humidifier is five-sixths of the bill
The pattern that runs through every page on this site holds here too. The blower costs about $4 a year; the heating element adds about $17. If you wanted to economise — and at these sums there is little reason to — the humidifier is the only lever that matters.
Heated tubing is a further element again and adds to both figures.
- How many watts does a CPAP use?
- Roughly 8W at a typical pressure with the humidifier off, and roughly 40W with heated humidification at a mid setting. Peak draw on startup is briefly higher.
- Does a CPAP use a lot of electricity?
- No. About 23 kWh a year dry, or 117 kWh humidified — for comparison, a typical fridge uses 300-500 kWh a year.
- Does leaving the CPAP plugged in all day cost anything?
- Standby draw is on the order of a watt or less, so a year of standby costs well under a dollar at typical rates.
Keep reading
- Does the CPAP humidifier drain the battery?
Yes — dramatically.
- Does a BiPAP use more power than a CPAP?
Yes.
- How long will a power station run a CPAP?
A 1,000Wh power station runs a typical CPAP for about 98 hours — roughly 12 nights — with the humidifier off.
- What size power station do you need for a CPAP?
For dry therapy, budget roughly 65Wh per night — so about 200Wh covers three nights.