For publication on lakelandcurrents.com
Table of Contents
- Why CPAP Users Should Plan for Outages
- How Much Power Does a CPAP Use?
- Calculating Runtime
- What to Look for in a CPAP Backup
- DC vs. AC Use
- Two Compact OUPES Options
- Charging and Preparedness
- Safety Notes
- FAQ
Why CPAP Users Should Plan for Outages
This article is general information, not medical advice. CPAP therapy is prescribed, so talk with your doctor or equipment supplier about what you should do if power fails, especially if your therapy is essential for your health.
A night without power is an inconvenience for most people. For someone who relies on a CPAP, it can mean disrupted sleep and symptoms the next day. Many people search for the best portable generator for CPAP machine use, but in most cases a battery power station is the better fit: it is quiet, produces no exhaust and can sit next to the bed.
How Much Power Does a CPAP Use?
OUPES’s appliance list shows a CPAP machine at about 40 W, which is a reasonable starting point. Your own draw depends on your pressure setting and accessories.
- Basic CPAP, no humidifier: often in the range of 30 to 60 W.
- With a heated humidifier or heated tube: noticeably higher, sometimes 60 to 100 W or more.
Check the label on your power adapter and your manual. The adapter rating shows the maximum, and typical use is lower. Confirm the wattage with your supplier if you are not sure.
Calculating Runtime
The formula is simple: usable watt-hours divided by draw. Usable energy is about 85 percent of the battery’s label because the inverter loses some to heat.
| CPAP draw | Exodus 350 (288 Wh, about 245 Wh usable) | Exodus 700 (576 Wh, about 490 Wh usable) |
|---|---|---|
| 40 W | about 6 hours | about 12 hours |
| 60 W | about 4 hours | about 8 hours |
| 90 W | about 2.7 hours | about 5.4 hours |
These are estimates. A full eight-hour night at 40 W needs about 320 Wh before losses, which is more than the smaller unit can deliver. A heated humidifier makes that gap larger.
Two ways to stretch runtime: turn off the heated humidifier or heated tube during an outage if your device and your clinician allow it, and use the machine’s own power-saving settings, if it has any.
What to Look for in a CPAP Backup
- Pure sine wave output: a clean waveform suited to sensitive electronics.
- Fast switchover: a UPS or EPS function that takes over within milliseconds when the grid drops.
- Capacity that fits your night: calculate for your own draw, with a margin.
- Quiet operation: it will be next to you while you sleep.
- Low weight: easy to move from a closet to the bedside.
- Recharge options: wall, car and solar for longer outages.
- Battery life: long cycle life means a unit you can rely on for years.
- App or display: a quick way to check the battery level.
DC vs. AC Use
Some CPAP machines accept a 12 V DC cable. Running a device on DC from the power station’s car-style socket can avoid inverter losses and stretch runtime. Only use the manufacturer-approved DC cable for your model. Do not improvise connectors. If your machine only supports AC, a pure sine wave outlet is the right choice.
Two Compact OUPES Options
The OUPES Exodus 350 provides 288 Wh and a 350 W pure sine wave inverter in a 9.15 lb package. Its UPS response is 10 ms or less, and it supports pass-through charging, so it can stay plugged in at the bedside and take over if the power drops. It suits shorter nights and lower-draw machines.
The OUPES Exodus 700 provides 576 Wh and a 700 W inverter at 13.9 lb, with the same 10 ms or less UPS response. The OUPES Exodus 700 offers more battery capacity for longer CPAP use, but it is not guaranteed to power every CPAP setup for a full night, especially when a heated humidifier or heated tube is used. Actual runtime depends on the CPAP model, heat settings, power draw, and whether the machine is connected through AC or an approved DC cable. Test your actual setup before relying on it during a power outage.. Both have 140 W USB-C ports, two AC outlets and a 12 V car socket.
| Exodus 350 | Exodus 700 | |
|---|---|---|
| Capacity | 288 Wh | 576 Wh |
| AC output | 350 W | 700 W |
| UPS response | 10 ms or less | 10 ms or less |
| Weight | 9.15 lb | 13.9 lb |
| 240 W solar, to full | about 1.5 hours | about 2.6 hours |
| List price at writing | $299 | $399 |
For more on the brand and its other products, see the OUPES Power station lineup.
Charging and Preparedness
A backup is only useful if it is charged and tested.
- Keep it plugged in. Pass-through charging lets it stay full while powering nothing.
- Test it. Run your CPAP on the unit for an evening and watch the battery level.
- Know your recharge options. A 240 W solar panel can refill a unit in good sun, and a 12 V car input works in a pinch.
- Keep the cables together. Put the AC cable, the CPAP cord and any DC cable in one bag.
- Plan for long outages. Ask your utility whether it keeps a list of customers who rely on medical equipment, and know where the nearest shelter or hospital is.
Safety Notes
- Never run a fuel generator indoors or in an attached garage. It produces carbon monoxide.
- Keep the power station dry, ventilated and within its working range of 0 to 40 °C (32 to 104 °F).
- Do not rely on any portable power station as your only plan if you use life-support equipment.
- Oxygen concentrators and ventilators often draw more power than a CPAP. Ask your provider before you plan around them.
FAQ
How long will a power station run a CPAP? At about 40 W, a 576 Wh unit can run roughly 12 hours. A heated humidifier shortens that.
Do I need a pure sine wave inverter? Pure sine wave output is generally recommended for sensitive medical electronics. Check your device’s manual.
Can I use the DC port instead of the AC outlet? If your CPAP supports a 12 V DC cable, DC can be more efficient. Use only the manufacturer-approved cable.
Will my CPAP switch over without turning off? A power station with a UPS response time of 10 ms or less is designed to switch over quickly when grid power fails. However, this rating does not guarantee uninterrupted operation for every CPAP model or setup. Test your actual CPAP and power connection to confirm whether the machine continues running during a power interruption. Consult your equipment supplier if you are unsure..
Should I ask my doctor before relying on a backup? Yes. Your doctor or equipment supplier can confirm your power draw and help you plan.
By: Chris Bates
