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Page dated 25 October 2026 · no products priced · not a hands-on test · not medical advice
Battery backup for a home oxygen concentrator: nameplate watts, whole-outage runtime
A home oxygen concentrator is a steady electrical load that cannot pause. That makes battery sizing simpler than a fridge or a sump pump, but less forgiving. This page covers the power side only: the watts on the label at your flow setting → runtime for the whole outage → cord straight to the pack → a full charge before the storm, with your supplier’s backup plan alongside.
Edited by K Singh. contact@outageshield.com. No invented patient stories. No test lab. No product prices on this page. Not medical advice.
A battery is a power plan, not an oxygen plan. Follow the backup plan from your prescriber and your oxygen supplier, which may include backup cylinders, and ask them what to do if power fails. Nothing here guarantees that any battery will run your concentrator. If you are short of breath in an outage, call 911.
This is a separate load from a CPAP. CPAP and fridge sizing is on battery backup for a CPAP and fridge. The 24-hour prep routine is on charge the night before. How loads drop off over several days is on what dies first in a multi-day outage. Your own runtime math goes in the runtime calculator.
Four-step summary
- Nameplate watts — the rating label and manual for your model, at the flow setting you use. Continuous draw, not a start surge.
- Whole-outage runtime — no duty cycle. Watts × hours of outage, plus inverter losses.
- Cord to the pack — plug the concentrator straight in. An inlet only if other loads already share it. No backfeed.
- Full at the start — charge the night before, and keep the supplier’s backup plan ready. A dead pack is not a medical plan.
1. Read the nameplate watts, not a guess
Find the rating label on the concentrator, usually on the back or the bottom, and the power section of the manual from the manufacturer or your supplier. Use those numbers. A figure from a different model, a forum, or a retailer listing is not your machine.
| Marking | What it means for backup |
|---|---|
| Volts / Hz | Home units in the US are typically 120 V, 60 Hz. If your label reads anything else, ask your supplier before planning. |
| Watts (or amps) | If only amps are listed, amps × 120 gives a rough watt ceiling. Running draw may be lower, but plan on the label. |
| Watts by flow setting (in the manual) | The flow setting changes the number. A higher setting usually means more watts. Use the figure for the setting you are prescribed. |
| Continuous vs surge | A concentrator is a continuous load. Size for the steady draw across hours, not for a start surge. |
If your supplier also gave you a portable concentrator with its own battery, that is a separate device with its own runtime chart. Ask the supplier how long it runs and how it recharges. Do not assume its numbers apply to the home unit.
2. A concentrator cannot pause like a fridge
A fridge cycles. Its compressor runs part of each hour, and a closed door lets it coast on cold food for hours. A concentrator delivers oxygen only while it runs. There is no duty cycle to bank on, so the runtime you need is the whole outage you are planning for.
Worked example (illustration only, not any model’s spec): suppose the label and manual give 300 W at your setting, and you plan for a 12-hour outage. 300 W × 12 h = 3,600 Wh. We assume about 85% of rated battery capacity is usable after inverter losses, so 3,600 ÷ 0.85 ≈ 4,240 Wh of rated capacity for the concentrator alone. Your own label number replaces the 300.
| Outage you plan for | Energy used | Rated capacity needed |
|---|---|---|
| 8 hours (overnight) | 2,400 Wh | ~2,820 Wh |
| 12 hours | 3,600 Wh | ~4,240 Wh |
| 24 hours | 7,200 Wh | ~8,470 Wh |
| 48 hours | 14,400 Wh | ~16,940 Wh |
Every other load on the same battery, such as a fridge, CPAP, router, or lights, comes out of the same watt-hours. Past a day, the honest answers are more capacity, a way to recharge, or the supplier’s backup supply. The sequence of what to keep and what to drop is on what dies first. Put your own watts and hours in the runtime calculator.
3. Cord to the pack is the path
| Path | When it fits | Honest limit |
|---|---|---|
| Cord straight into the battery | The default. Plug the concentrator’s own cord into a 120 V AC outlet on the pack | Follow the manual on extension cords and power strips. The pack sits where it can be seen and heard. |
| Inlet + interlock | Only if other must-run loads already share that inlet, and a licensed electrician installed it | The battery must cover every kept circuit at once. Detail: inlet & interlock. |
Never feed house wiring through a dryer or wall receptacle. Panel work is a licensed electrician’s job, with a permit where your AHJ requires one. Never run a generator indoors or in an attached garage, and keep oxygen equipment away from open flame.
4. Charge the night before, and keep the backup plan
The math above only works if the pack is full when the power goes out. Wall-charge to 100% the night before any forecast outage, and run one short test on a mild day so you know the concentrator starts on the battery. The full 24-hour routine is on charge the night before. Between storms, check the charge level on a calendar, because packs lose charge sitting on a shelf.
A dead pack at the start of an outage is not a medical plan, and neither is a full one on its own. Ask your prescriber and oxygen supplier what their backup plan is, which may include backup cylinders, and keep their phone numbers on paper. Many utilities let you register a household that depends on medical equipment. Ask yours what that covers, since it does not guarantee faster restoration.
5. How this connects
- This page — nameplate watts, whole-outage runtime, cord to the pack.
- A different medical load — CPAP and fridge backup.
- Before the storm — charge the night before.
- Multi-day sequence — what dies first.
- Your numbers — runtime calculator; keep list — checklist.
FAQ
Sources and method (25 October 2026)
- Your concentrator’s rating label and manufacturer or supplier manual govern the watts; this page names no model and quotes no model’s spec
- The 300 W figure is an illustration for the math only
- ~85% usable capacity after inverter losses is the same planning assumption used across OutageShield
Next step: read the label watts at your flow setting, then size for the whole outage.
Runtime calculator Charge the night before CPAP + fridge Find my backupEditor: K Singh. Page dated 25 October 2026. No product prices on this page. Not a hands-on test. Not medical advice. We do not guarantee that any battery will run your oxygen concentrator. Follow your prescriber’s and supplier’s backup plan.