What size power station do I need for CPAP machine?
CPAP machine
Default appliance profile before model-specific measurements.
The supplied baseline estimates a CPAP machine at 45 W for 8 hours per day, or about 360 Wh daily. It lists a 70 W startup/surge demand and a usage uncertainty of ±30%.
Applying the stated 88% inverter efficiency, 90% usable fraction, and 15% reserve margin gives a one-day nominal battery target of about 523 Wh. Model-specific energy use is not provided, so actual runtime may differ; a plug-in power meter or manufacturer energy label is preferable when available.
- Battery size: Choose about 523 Wh nominal capacity for the supplied one-day estimate.
- Inverter capacity: It should cover at least the listed 70 W startup/surge demand.
- Before buying: Confirm the CPAP’s actual consumption and settings, since the supplied evidence does not identify a specific model or provide measured usage.
Using the default load profile, cpap machine consumes about 360 Wh/day. A conservative one-day battery target is about 522 Wh nominal capacity, while the inverter should cover at least 70 W of startup demand.
Assumptions behind the calculation
- Running draw: 45 W
- Startup/surge: 70 W
- Default use: 8 h/day
- Duty cycle: 100%
- Usage uncertainty: ±30% before model-specific measurements
Actual energy use varies by appliance model, ambient conditions, settings and load. A plug-in power meter or manufacturer energy label is preferable when available.
Runtime by battery size
| Station capacity | Continuous-draw runtime | Default usage profile |
|---|---|---|
| 300 Wh | 5.3 h at continuous draw | 0.7 default-profile days |
| 500 Wh | 8.8 h at continuous draw | 1.1 default-profile days |
| 1000 Wh | 17.6 h at continuous draw | 2.2 default-profile days |
| 1500 Wh | 26.4 h at continuous draw | 3.3 default-profile days |
| 2000 Wh | 35.2 h at continuous draw | 4.4 default-profile days |
| 3000 Wh | 52.8 h at continuous draw | 6.6 default-profile days |
Use your actual household loads
The calculator combines this appliance with refrigerators, networking, pumps, medical equipment and other essentials so simultaneous wattage and motor startup are not ignored.