Oxygen Concentrator on Battery Power: Sizing Guide for Power Outages

A stationary oxygen concentrator runs 24 hours a day, 7 days a week, drawing between 310 and 350 watts every hour it is on. That comes to 7,440 to 8,400 watt-hours per day. For context, the largest portable power stations on the market today hold about 4,000 to 5,000 watt-hours. Even the biggest single-unit battery covers less than half a day of stationary concentrator operation.

This is not a solvable problem in the way that backing up a CPAP machine is. A CPAP draws 40 to 56 watts and runs for 8 hours. An oxygen concentrator draws six to eight times more power and runs three times as long. The math is sobering, and this article will not pretend otherwise.

What a power station can do is buy time. Time for the grid to come back. Time for a generator to arrive. Time to execute an emergency plan that keeps oxygen flowing while you figure out the next step. Understanding exactly how much time a given battery provides, and how to extend it, is the purpose of this guide.

This guide provides sizing estimates based on OEM-published specifications, not medical advice. Your prescription, flow settings, and clinical needs determine your actual requirements. Always consult your physician or DME provider before making backup power decisions for life-support equipment.

60-second sizing

1. Identify your concentrator type. Stationary home units (Philips EverFlo, DeVilbiss 5L) draw 310 to 350W. Portable units (Philips SimplyGo) draw 120W. Never assume wattage: check the label on your specific device.
2. Pick your runtime target. 8 hours covers an overnight outage. 24 hours covers a full day without grid power. 72 hours requires an expandable battery system, solar recharging, or a generator rotation.
3. Size the battery.

Stations under 1,000 Wh provide less than 2 hours for a stationary concentrator. That is not enough for overnight backup. If you use a heated humidifier or other powered accessories with your concentrator, add their wattage to your total before sizing.

Jump to the emergency planning checklist if you already know your numbers and want the full backup protocol.

Power Draw by Concentrator Type

Oxygen concentrators fall into two categories: stationary units designed for home use and portable units designed for travel. The power difference between them is enormous and it fundamentally changes your battery backup calculus.

Stationary concentrators (home units)

These are the workhorses of home oxygen therapy. They plug into a wall outlet, weigh 30 to 40 pounds, and deliver continuous flow oxygen at rates from 0.5 to 5 liters per minute (LPM). They run around the clock and are not designed for battery operation.

Philips Respironics EverFlo (model 1020000): 350W average power consumption. Input voltage 120 VAC, 60 Hz. Flow rate 0.5 to 5 LPM. Oxygen concentration 93% (plus or minus 3%) at all flow rates. Weight 31 pounds. This is one of the most widely prescribed home concentrators in the United States and serves as our baseline for stationary sizing calculations.

Drive DeVilbiss 5 Liter (model 525DS): 310W average power consumption. At flow rates of 1.2 LPM and below, draw drops to approximately 275W thanks to the patented DeVilbiss Turn-Down Technology that reduces compressor output at lower settings. Flow rate 0.5 to 5 LPM. Oxygen purity 87% to 96%. Weight 36 pounds.

Both stationary units draw their rated wattage continuously with no meaningful startup surge. Unlike a refrigerator compressor or an air conditioner, a concentrator’s compressor ramps gradually. No published startup current data exists for either model, so we model surge as equal to running watts. This means any power station rated at 500W or above has more than enough output capacity. The constraint is never wattage. It is always battery capacity.

Portable concentrators (travel units)

Philips Respironics SimplyGo (model 1068987): 120W operating power, 150W while charging the internal battery. Continuous flow up to 2 LPM, pulse dose up to setting 6. Weight 10 pounds with battery. AC input 100 to 240 VAC, 50/60 Hz.

The difference is dramatic. At 120W operating draw, the SimplyGo consumes roughly one third the power of a stationary unit. That means a power station lasts nearly three times as long running a portable concentrator compared to a stationary one.

How Long Will a Power Station Last?

This is the central question, and the answer requires honest math. We use a 0.70 derate factor in all runtime calculations. This accounts for inverter conversion losses (typically 10 to 15 percent), battery voltage sag as state of charge drops, and reduced efficiency at partial loads. It is a conservative figure. Some units will exceed it. But for life-critical equipment, conservative is the right approach.

Stationary concentrator runtime (350W baseline)

Using the Philips EverFlo at 350W as our reference:

The numbers tell a clear story. The largest single-unit portable power station in our database, the EcoFlow DELTA Pro 3 at 4,096 Wh, provides about 8.2 hours of runtime for a stationary concentrator. That is one third of a day. No single portable power station currently on the market can sustain a stationary oxygen concentrator for a full 24-hour cycle.

If you are using the Drive DeVilbiss 5L at 310W, runtimes improve modestly. The EcoFlow DELTA Pro 3 would last approximately 9.2 hours (4,096 × 0.70 / 310). Better, but still well short of a full day.

Portable concentrator runtime (120W baseline)

The picture changes considerably with a portable unit. Using the Philips SimplyGo at 120W operating draw:

The Jackery Explorer 2000 Plus provides roughly 11.9 hours. The Goal Zero Yeti Pro 4000 stretches to 23.3 hours. With a portable concentrator and a large battery, you can approach a full day on a single charge.

Daily energy demand in perspective

Here is the number that puts everything in context:

A stationary concentrator at 350W running 24 hours consumes 8,400 Wh per day. At 310W, it consumes 7,440 Wh per day.

A portable concentrator at 120W running 24 hours consumes 2,880 Wh per day.

Those are large energy demands. For comparison, the average American household uses about 30,000 Wh (30 kWh) per day across all appliances. A stationary oxygen concentrator alone accounts for roughly 25 to 28 percent of that total.

Multi-Day Strategies That Actually Work

Before diving into multi-day setups, make sure you understand the two numbers that matter:

• Power (watts): Can this station run my concentrator right now? A 350W concentrator needs a station rated above 350W continuous output. This is almost never the bottleneck because even small stations output 500W or more.
• Energy (watt-hours): For how many hours can it run? A 2,000 Wh battery at 350W lasts about 4 hours after derate. This is always the bottleneck.

If you need more than 8 hours of backup, and most oxygen-dependent patients do, a single power station is not sufficient. You need a system. Here are the approaches that work in practice, ranked from simplest to most complex.

1. Expandable battery systems

Several manufacturers offer modular battery ecosystems where you can add expansion packs to a base unit:

The Jackery Explorer 2000 Plus starts at 2,042 Wh and accepts up to five add-on battery packs for a total system capacity of approximately 12,000 Wh. At 350W, that provides roughly 24 hours of stationary concentrator runtime (12,000 × 0.70 / 350 = 24 hours). It is the simplest path to full-day coverage, though it requires a significant investment in hardware.

The EcoFlow DELTA Pro Ultra starts at 6,144 Wh per battery and scales up to 90,000 Wh (90 kWh) with expansion units. This is a whole-home backup system, not a portable power station. At 350W, a single 6,144 Wh battery provides approximately 12.3 hours (6,144 × 0.70 / 350). Two batteries provide roughly 24.6 hours.

The Goal Zero Yeti Pro 4000 accepts up to four Tank Pro 4000 expansion batteries (3,994 Wh each) for a maximum system capacity of approximately 19,970 Wh. At 350W, that covers about 39.9 hours (19,970 × 0.70 / 350).

2. Solar recharging

If you pair a large battery with 400 to 600 watts of solar panels, you can create a system that recharges during daylight hours while your concentrator continues to run. In full sun conditions (roughly 4 to 6 peak sun hours per day in most of the continental US), a 400W solar array produces approximately 1,600 to 2,400 Wh per day. That offsets 19 to 29 percent of a stationary concentrator’s daily demand, or 56 to 83 percent of a portable concentrator’s demand.

Solar is not a guaranteed solution. It depends on weather, season, panel orientation, and shading. But combined with a large battery, it turns a one-day backup into a multi-day system.

3. Pass-through charging (UPS mode)

Some power stations support pass-through charging, where the unit stays plugged into the wall outlet and your concentrator stays plugged into the power station. When the grid is live, electricity flows through the station to your device while keeping the battery topped off. When the grid fails, the station switches to battery power.

The critical specification here is switchover time: how many milliseconds the transition takes. For an oxygen concentrator, a brief interruption of a few hundred milliseconds will not cause any medical issue because the air in the tubing and your lungs bridges the gap. But a clean switchover is still preferable for a practical reason: most stationary concentrators trigger a loud power-loss alarm when AC input drops. If your battery does not switch fast enough, the concentrator shuts down, the alarm sounds, and a sleeping patient wakes in a panic. A station with UPS-speed switchover (under 20ms) prevents this entirely.

Anker SOLIX C300 (288 Wh): less than 10ms switchover time. At 288 Wh capacity, this unit provides only about 0.6 hours of runtime for a stationary concentrator. It works as a UPS bridge for very short outages, not as a standalone backup.

Zendure SuperBase V4600 (4,608 Wh): 1ms switchover, effectively instantaneous thanks to its GridFlow 2.0 bidirectional inverter technology that maintains constant AC output. At 4,608 Wh, it provides approximately 9.2 hours of stationary concentrator runtime (4,608 × 0.70 / 350). This is one of the few units that combines near-instantaneous switchover with meaningful battery capacity.

4. Generator plus battery hybrid

A gasoline or propane generator can run your concentrator during waking hours, while a battery takes over at night when you need quiet operation. This approach works well for multi-day outages where solar alone is insufficient. The battery charges from the generator during the day and discharges overnight, creating a sustainable rotation.

This is how many home oxygen users survived extended outages during Hurricane Ida (2021) and the February 2021 Texas winter storm. It is not elegant, but it works.

The Portable Concentrator Advantage

If your prescription allows it, a portable oxygen concentrator at 120W is dramatically easier to back up than a stationary unit at 310 to 350W. The math speaks for itself:

A single EcoFlow DELTA Pro 3 (4,096 Wh) runs a portable concentrator for approximately 23.9 hours. Add a modest 200W solar panel producing 800 to 1,200 Wh per day in good conditions, and you can sustain a portable concentrator indefinitely.

Some portable concentrators also have their own internal batteries that provide limited runtime without any external power source. The Philips SimplyGo provides approximately 54 minutes of continuous flow at 2 LPM on its internal battery, or up to 3 hours on pulse dose setting 2. That is not much, but it covers the gap while you switch power sources or move to a location with electricity.

The trade-off is flow rate. Portable concentrators max out at 2 to 3 LPM continuous flow. If your physician has prescribed 4 or 5 LPM continuous, a portable unit cannot meet your needs. This is a medical decision, not a battery decision. Talk to your doctor about whether a portable concentrator at a lower flow rate with pulse dose delivery could maintain adequate oxygen saturation during an emergency, even if it is not your everyday prescription.

Emergency Planning Checklist

Battery backup is one layer in a multi-layer emergency plan. For oxygen-dependent patients, the stakes are too high for a single point of failure.

Register with your electric utility for medical priority restoration. Most US utilities maintain a medical baseline or life-support registry. Being on this list does not guarantee faster restoration, but it flags your address for priority consideration during planned and unplanned outages. Contact your utility’s customer service line and ask about their medical equipment or life-support program.

Keep a minimum 72-hour supply of backup oxygen tanks. Compressed oxygen tanks (E-cylinders) provide approximately 5 to 6 hours of oxygen at 2 LPM continuous flow. Three to four E-cylinders cover 24 hours at moderate flow rates. Your home medical equipment (HME) provider can arrange delivery and help you determine the right number of tanks for your flow rate. This is your absolute last-resort backup and it should always be available regardless of what battery system you own.

Test your exact setup monthly. Unplug your concentrator from the wall, switch to battery power, and confirm that everything operates as expected. Use the same cables, the same outlet on the power station, the same flow rate setting, and the same accessories (humidifier, heated tubing) you would use during an actual outage. Check that pass-through switching works, that the battery holds its rated capacity, and that alarms (both on the concentrator and the power station) function properly. If you live in a region with temperature extremes, test in summer and winter because lithium batteries lose capacity in cold conditions. Do this during the day when you are awake and alert, not at 2 AM during an actual outage.

Know your power station’s actual runtime. Run a full discharge test at least once. Plug your concentrator into a fully charged power station and let it run until the battery dies. Record the actual runtime. Compare it to the calculated estimate. If actual runtime is significantly shorter than expected, the battery may be degraded and need replacement.

Have a Plan B location. Identify a friend, family member, or nearby facility (hospital, fire station, community shelter) with generator power where you can go if your battery runs out and the grid is still down. Know how to get there and how long the trip takes. Keep a portable concentrator or backup oxygen tank ready for transport.

Contact the HHS emPOWER Program. The Department of Health and Human Services maintains the emPOWER Map, a tool that tracks Medicare beneficiaries who depend on electricity-powered medical equipment. Over 4.6 million Medicare beneficiaries are in this database. Your local emergency management agency can use this data to prioritize outreach during disasters. While the program works through public health agencies rather than individual registration, awareness of it helps you advocate for services in your area.

Next Steps

If you also use a CPAP machine, the CPAP Machine Battery Backup Guide covers that lower-draw device in detail. And the How to Size a Portable Power Station guide walks through the general sizing framework that applies to any device, including medical equipment.

Sources: Device wattage from OEM manuals and spec sheets in the GeneratorChecker device database. Philips EverFlo (model 1020000) specifications from Philips Respironics product documentation. Drive DeVilbiss 525DS specifications from DeVilbiss product literature. Philips SimplyGo (model 1068987) specifications from Philips Respironics product documentation. HHS emPOWER data from HHS emPOWER Program. Food safety and emergency oxygen guidance from Medicare and HME provider best practices. Methodology: How we source and verify device data.