How to plan backup power for a CPAP or other powered medical device, what to ask your clinician and how to size a battery.
- Talk to your clinician and utility before an outage, not during one.
- Size a battery from the device's watts x hours, then add margin.
- Test your whole backup setup for a night at home.
Step 1: know your device
Find the power rating (watts or volts and amps) on the device label or in the manual. Write it down. Also note whether it needs a heated humidifier, which uses much more power.
Step 2: ask the right people
- Your clinician or supplier: what to do if the device cannot run, and which backup options they approve.
- Your utility: many utilities keep a register of customers who rely on powered medical equipment and can give notices.
- Your device maker: some sell approved battery packs or DC power options.
Step 3: size a battery
Watts x hours = watt-hours. For example, a 40 W device used 8 hours needs 320 Wh. Divide by 0.85 for conversion losses: about 375 Wh. Choose a unit with margin and test the whole setup at home for a night before you need it.
| Check | Why |
|---|---|
| Rated output of the power station | Must exceed the device's watts, with margin |
| Output type | Some sensitive devices want pure sine wave AC or a specific DC connector. Check the device manual |
| Heated humidifier | Turn it off or plan for much higher consumption |
| Recharge plan | How you will recharge during a multi-day outage |
Backup habits
- Keep batteries charged year-round and test them every few months.
- Keep a written plan, and a list of numbers, with the device.
- Have a week of prescriptions on hand.
Power stations to look at
Use our outage planner to estimate your watt-hours, then compare in the right size band.
Quick comparison
| Brand | Best for |
|---|---|
| JJackery | Wide range, compact to home backup sizes |
| EEcoFlow | Fast charging and expandable systems |
| BBLUETTI | Large lineup, expandable home systems |
Compare sizes and output types for your device.
- Has a Canadian store
- Small, mid and large models
- Compare capacity, output and warranty on the maker page
Compare sizes and expansion options.
- Markets fast charging, so compare charge times
- Expandable systems in larger sizes
- Check solar input specs
Compare sizes and output types.
- Broad capacity range
- Expandable home-backup options
- Compare battery chemistry and stated cycle life
Quick answers
Can a power station run a CPAP?
Many can, if the output covers the device's watts. Check your device manual and consult your clinician.
Should I use a heated humidifier on battery?
It uses much more power. Many people turn it off during outages. Ask your clinician.