How to Choose a Best Portable Power Station for Your CPAP

People with sleep apnea rely heavily on CPAP devices to get a good night's sleep. CPAP (Continuous Positive Airway Pressure) helps people to breathe more steadily and without interruptions or blockages. These devices are lightweight and portable, meaning people can do CPAP therapy in the comfort of their own homes, while traveling, on the road, or while camping and adventuring outdoors.

CPAP devices must have some form of uninterrupted power source at all times. In regions with frequent power outages, this can represent a serious health hazard for people with sleep apnea, making it critical to find alternative, off-grid energy sources, such as portable power stations or solar generators. In 2020, American customers and homeowners suffered a devastating total of 1.33 billion power outage hours - 73% more than in 2019.

This article will cover everything you need to know about how to power CPAP machines off the grid, along with a brief introduction to these off-grid energy solutions (and how they work) - including our #1 pick in solar generators for CPAP available on the market. Better sleep nights, improved health, and a significant upgrade in the quality of life are just one quick read away.

1. How Much Power Does a CPAP Use?

1.1 Explaining Power Consumption

When calculating power consumption on any home appliance or machine, there are three variables we must first understand: electrical current (A), voltage (V), and power (W). Power, expressed in watts, equals electrical current multiplied by voltage.

Virtually all home appliances come with tech specs where we can find this data, making it easy to discover how much power our appliances and gadgets are consuming within our power grid. We can make a practical example with something all of us have and use daily - a smartphone charger.

Usually, current phone charger models have a quick charge feature, meaning they perform at a higher amperage than previous models, so we'll use those standard numbers, which you can find under the DC Output category:

Power (W) = Current (A) x Voltage (V)

Power (W) = 5A x 3V

Power (W) = 15W

For all CPAP machines that we'll discuss over the next segment, there are two more concepts that we need to consider: typical (average)and peak (working at total capacity) power consumption - both expressed in watts. Variables such as altitude, temperature, time of use, machine lifespan, and constant humidifier usage contribute to higher power consumption.

1.2 CPAP Power Consumption

CPAP machines are no different. In the past, the first CPAP devices came with limited features and simple datasheets. They would usually consume anywhere between 30 to 60 watts. Current models are a bit more elaborate, and the most basic CPAP device, with a built-in air humidifier, consumes an average of 53 watts with a peak power consumption of 104 watts.

Another thing we need to discuss is that not all CPAP machines are alike. In terms of the inner workings, we can talk about three different types of devices: CPAP (Continuous Positive Airway Pressure), APAP (Automatic Positive Airway Pressure), and BiPAP (Bilateral Positive Airway Pressure). We picked one of the best-selling devices for each category to explain power consumption better and more realistically.

CPAPs have only one airflow setting, making them the cheapest and most readily available device among the three. They're ideal for people with mild sleep apnea and no other chronic respiratory conditions: such as sinusitis, rhinitis, or asthma.

  • Power Consumption:53 W
  • Peak Power Consumption:104 W

APAPs have an automatic, self-regulating airflow system, which varies throughout the night according to your respiratory needs. They're ideal for people who move a lot during sleep (because different sleeping positions demand more or less air pressure) and those with moderate to severe sleep apnea.

  • Power Consumption:56.1 W
  • Peak Power Consumption:73.2 W

BiPAPs are very similar to CPAPs, but instead of having only one air pressure configuration for both inhalation and exhalation, BiPAPs have two different settings (one for each). They're ideal for people who find it difficult to get used to CPAPs because of constant choking (due to a lack of synchronicity between both respiratory movements).

  • Power Consumption:53 W
  • Peak Power Consumption:104 W

Additionally, most modern CPAP (or APAP, or BiPAP) devices feature built-in electronic boards to control their functionalities. All electronic devices require a cleaner energy supply called Pure Sine Wave, which, unlike the conventional Modified Sine Wave, produces an almost identical sinusoidal pattern to the one coming from the power grid - protecting your electronics and improving their lifespan.

2. How to Power CPAP Machines Off-Grid?

As previously mentioned, CPAPs require a steady power supply, both on and off-grid. Off-grid solutions depend on external power sources, such as power banks, car batteries, generators, or extension cords (to plug into the closest grid). Let's take a closer look at the options:

2.1 External Electricity Hookups

While technically an on-grid solution, external power hookups are becoming increasingly available at most on-the-road locations, such as camping sites, gas stations, motels, truck stops, etc. Be careful, though. These hookups are usually rather expensive, even if it's just for the night. Plus, there are no guarantees that the power supply will be clean and steady, which could damage your CPAP and put your health at risk. Not to mention you'll need a robust extension cord, as well.

2.2 Car Batteries

Now that we've covered and explained power consumption, we can understand why your car battery should be your absolute last resort option. Imagine your CPAP consumes 90 watts. We consider that all car batteries produce roughly 12V, so we'll suppose your car's battery has a 48Ah of electric charge (amperage per hour).

how much power does a CPAP use - Growatt

For every hour, you'll be effectively depleting 7.5A from your battery, meaning if you don't recharge it, you'll theoretically drain your battery in 6h24m. We say theoretically because discharged batteries don't need to reach complete power depletion to stop working.

A drained-off battery can become a nightmare, depending on the context. Also, depleted batteries are more difficult to fix due to possible sulfation in their components.

2.3 Portable Power Stations

Also known as generators, these portable power stations remain the superior choice when powering your CPAP off-grid. Bear in mind, though, that not all generators are alike. Generators fueled by hydrocarbons (such as gasoline, diesel, and natural gas) have the advantages of being inexpensive and easy to find. However, CPAP users won't find them a good fit for two reasons:

  • Carbon footprint is detrimental to the environment, and these generators might even lead to pulmonary intoxication and even death if used indoors due to the released carbon dioxide.
  • Even the quietest hydrocarbon generator is still audible, meaning these portable power stations are not a great idea when trying to get a good night's sleep.
solar generator for CPAP - infinity 1500 - Growatt

The best option remains to opt for a solar generator for CPAP. They are quiet, portable, versatile, and friendly to the environment - all while still being powerfully efficient.

3. How to Choose the Best Solar Generator for CPAP?

Solar generators take care of all our problems related to off-grid CPAP usage. Furthermore, solar generators offer countless advantages over fuel-powered generators, such as clean energy, ease of use, portability, versatility (functioning as both a UPS power bank and an energy generator), and little to no noise generation. However, before we swing into our #1 pick in solar generators, there are some considerations to discuss and understand.

3.1 Battery - Lead-Acid v. Li-ion

Generators powered by lead-acid batteries are cheaper and more widely available. However, they are also much heavier and require scheduled battery maintenance, not to mention the slight risk of battery leaking if handled poorly (lead is highly toxic to all living beings).

Li-ion batteries have a higher initial cost. On the bright side, they last longer, need no upkeep and are considerably lighter (which helps with portability).

3.2 Power Sizing Measurements

Lastly, you want to ensure the generator of your choice will fulfill all your power requirements without ever coming short (or being overkill).

First, we can discuss running wattage or the electricity the generator can continuously deliver. Make a list of all the essential appliances you'd like to plug in, in the event of a power outage or when on the road. The total running wattage offered by a generator needs to be higher than the sum of your power needs.

Secondly, we have capacity expressed in watt-hours (Wh). This measurement unit tells you how much power the generator can provide at 100% battery charge before needing to recharge. For example, if a generator offers 1500Wh, it can power 3x100W appliances (total 300W) for 5 hours or 2x75W devices (adding 150W) for 10 hours.

Another way of tackling capacity is knowing how long you'll be away from the power grid. If you're only staying away overnight, then there's no need to get a large generator for your gadgets. In most cases, smaller power banks (roughly around 500Wh or less) are more than enough for a good night's sleep before you hit the road again.

On the other hand, if you mean to go camping, road-tripping, or otherwise explore the wilds for many consecutive days, these small-size power banks won't suffice. If you plan to go out for three (or more) days, we strongly recommend you get a large-capacity portable power station.

Lastly, there is peak power, also measured in watts. Some home appliances, such as fridges, fans, and portable air conditioning units, require an elevated power spike to kickstart their functions. If the peak power offered by a generator is lower than what your device needs, it won't start.

4. Best portable power station for CPAP

With everything we have discussed, we can present our #1 Pick in Solar Generators for CPAP in the market, the Growatt Infinity 1500 Portable Power Station from Growatt.

4.1 Growatt Infinity 1500 Portable Power Station - How Long Can CPAP Machines Run?

The answer to this relies entirely on the technical specifications of your CPAP device. From what we've learned up until here, we know that the lower the power consumption of a CPAP machine, the longer our solar generator can power it. We also know that the higher the number of appliances plugged in at once, the shorter the solar generator autonomy will be.

We've prepared three different scenarios, all telling the same story. The only variables will be the type of CPAP machine in use and whether or not the humidifier will work throughout the night.

Best portable power station for CPAP - Growatt

Imagine you're out in the woods, camping with two more friends. Before dusktime, you managed to recharge the Infinity 1500 Portable Power Station back to 100% - a total capacity of 1512Wh. Before bedtime, you'll connect one type of CPAP machine and three phone chargers (15W each).

Scenario #1 - CPAP machine (with humidifier)

The total energy demand could reach 149Wh, meaning:

  • You'll get 10h09m (with the phone chargers), or
  • You'll get 14h32m (with only the CPAP).

Scenario #2 - APAP machine (with humidifier)

The total energy demand could reach 118.2Wh, meaning:

  • You'll get 12h48m (with the phone chargers), or
  • You'll get 20h40m (with only the APAP).

Scenario #3 - BiPAP machine (without humidifier)

The total energy demand could reach 98Wh, meaning:

  • You'll get 15h26m (with the phone chargers), or
  • You'll get 28h32m (with only the BiPAP).

As you can see, even at the highest performance and demand, the Infinity 1500 Portable Power Station satisfies all your needs, with enough energy remaining to kickstart the next day before needing to recharge.

If you are familiar with the power consumption of your appliances, you can determine how long you'll be able to run them using this portable power station. For example, an older CPAP machine only uses 30W, meaning this solar generator can run it for 50 hours!