What Size Power Station Do I Need for a CPAP Machine?
A CPAP machine is a critical overnight device, and sizing a power station for it requires understanding how a heated humidifier and heated tube change the power equation. This page helps you calculate backup capacity for a full night's sleep and explains the safety considerations for medical equipment.
For a CPAP without a heated humidifier, a 300–500 Wh power station may cover a full 8-hour night. With a heated humidifier and heated tube, consumption can double or triple — plan for 500–1,000 Wh depending on your machine and settings. Always verify your specific machine's wattage.
This calculator is not a substitute for medical equipment safety certification. A power station is not a medically certified backup power system. If you depend on a CPAP for health, consult your equipment manufacturer and your doctor for guidance on backup power, and consider a dedicated medical-grade UPS.
Calculate Your Exact Size
Preconfigured for cpap. Adjust the values below, then calculate.
Typical Power Requirements
| Specification | Typical Range |
|---|---|
| Running watts (W) | 30–130 W |
| Default runtime scenario | 8h |
These are planning ranges only. For the most accurate result, check the appliance label or manufacturer's specification and enter the actual wattage in the calculator above.
Key Considerations
- The base CPAP blower typically draws 30–60 W, but a heated humidifier can add 40–80 W and a heated tube adds another 10–20 W. Check your machine's settings — the difference between 'no humidifier' and 'humidifier + heated tube on max' can be 3× the power.
- Some modern CPAP machines have a 12V DC input, which is more efficient than using an AC inverter. If your machine supports DC, use it — you avoid the ~15% inverter loss.
- Altitude settings can increase blower power consumption. If you're at high altitude, expect higher wattage.
- This calculator is not a substitute for medical equipment safety certification. Consult your equipment manufacturer for backup power guidance.
Runtime Examples
Roughly 10–11 hours of runtime after efficiency losses — enough for a full night. If your machine includes a humidifier and draws 80 W, this drops to about 5 hours.
About 10–11 hours with humidifier running — enough for a full night even with heated tube and humidifier on. A safe choice for CPAP users who want margin.
Solar Considerations
- For camping or off-grid CPAP use, a 100–200 W solar panel can recharge a 500 Wh station during the day for repeated overnight use.
- CPAP is primarily an overnight load, so solar doesn't help during use — it helps you recharge for the next night.
Compatible Power Stations
Based on the preconfigured cpap scenario. Calculate above for recommendations tailored to your exact setup.
Buying Considerations
- If your CPAP supports 12V DC input, look for a power station with a 12V/24V DC output port to avoid inverter losses.
- Prioritize capacity over surge — CPAP machines have minimal startup surge. The continuous output just needs to exceed your machine's max wattage.
- Consider noise level — some power station fans can be audible in a quiet bedroom. Check reviews for sleep-friendly noise levels.