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The best portable power stations aren’t exactly always portable, with sizes ranging from 15 pounds to 100 pounds. Still, these relatively compact devices can provide a lot of power. Whether you’re going off-grid, need power during an outage, or are simply camping for the weekend, portable power stations are essential for keeping devices and appliances powered and ready to go.
We ran dozens of portable power stations through the gauntlet in our lab in Kentucky, evaluating how much power each station can provide relative to how much it draws to charge, to determine its overall efficiency.
Also: The best portable power stations for camping
The portable power stations that stood out above the rest were the Bluetti AC240 for large-size power stations (devices with 1,100-2,100Wh), and the Oupes Mega 1 for small portable power stations (devices with 600-1,100 Wh). We chose to separate these awards and power stations because batteries of different sizes would yield different outcomes, so comparing devices that are closer in battery capacity provides more accurate results.
Portable power stations were tested for power consumption over time, measured in watt-hours (the total energy used or produced). We chose to compare 10 portable power stations based on our portable power station expert, Adrian Kingsley-Hughe’s real-world recommendations, as well as the products we’ve tested in our lab.
How we tested these portable power stations
Our lab testing process centers on measuring the charge and discharge processes of each portable power station, with emphasis on the number of watt-hours consumed and discharged, respectively, and the time required to complete each process.
Once all data was gathered, we also compared units using a “Round Trip Efficiency” metric that describes how efficiently a unit delivers power relative to how much it draws to charge.
According to Bryan Adams, the Senior Lab Engineer, the testing apparatus consists of the unit under test (UUT), a HOBO plug load data logger, a computer to save the logged data, and a 480W LED light to consume power.
During a charge test, the UUT is plugged into the wall, with the data logger measuring and logging the power (watt-hours) drawn by the unit. The log shows us how long this process takes, giving us our two key takeaways (power and time).
Also: How we test portable power stations at ZDNET
Adams said that the lab primarily tests for watt-hours in either direction because they provide the best indication of power usage over time. For example, a unit that provides 100 watts for 10 hours provides 1000 watt-hours. If you plug in a 200W load, the unit will only run for five hours, which still ultimately adds up to a capacity of 1000 watt-hours.
Additionally, the charging time is a key metric of interest to people, and we measure the time to discharge when connected to a 480W load to provide a standard frame of reference for discharge times.
The results
To best understand our data visualizations, the power stations with higher watt-hours per time charged were the top performers. This means that, for large portable power stations (Figure 1), the top performer was the Bluetti AC240, which is why it won our Lab Award badge.
The Lab Award for the small, portable power station with the best efficiency (Figure 2) went to the Oupes Mega 1. The Bluetti AC240 took 74 minutes to charge to 100%, while the Oupes Mega took 21 minutes.
Read the reviews: Bluetti AC240 | Oupes Mega 1
The close runner-up power stations were the Vtoman Flashspeed 1500, which had the same charging time as the Bluetti but a slightly higher watt-hour rating. In the small category, the DJI Power 1000 placed second for efficiency, with a runtime of 33 minutes.
Power stations that take longer to charge per watt-hour are less efficient. In the case of large portable power stations, that means the Anker 757 Powerhouse, and for small power stations, the EcoFlow River 2 Pro. However, this does not mean that these are poor-performing portable power stations.
Our tests might differ from your own experience, depending on how you use a portable power station. However, as a general baseline, our testing provides an expert analysis of how these portable power stations perform and identifies the use cases for which they are best suited.
The primary distinction between portable power stations and gasoline generators lies in their energy sources and operation. Portable power stations are equipped with batteries that are pre-charged with electricity before use. In contrast, gasoline generators rely on gasoline, which is burned in an engine to produce electricity.
Simple: Find your biggest power draws and replace them with more energy-efficient alternatives. For example, you might find that you can replace that 1,000W heater with a heated throw that only takes 100W to power. That quilt would run for 10 hours on the power that the heater would use in an hour.
Another big power hog is incandescent lights. Swapping these out for LEDs will result in huge power savings and dramatically boost your power station’s runtime.
Another tip is that if you need to use USB charging, use the ports on the unit, and don’t go plugging in chargers, as this is more inefficient.
Power stations are a significant investment, but they can ultimately upgrade your camping experience to allow for power off-grid. Before making our top picks, we considered several factors.
- Weight: Bigger isn’t always better, especially when it comes to camping. Will the portable power station be wheeled down a paved trail, or will you be moving it from your vehicle to your camp? Do you want something you could carry in a backpack for a day?
- Battery capacity: If you plan to power an RV or bigger devices from your power station, you want as much battery capacity as you can afford, but for off-grid adventures, it’s important to bear in mind that there’s a penalty here in the form of weight.
- Cost: Some units cost several thousand dollars, while others cost a couple hundred. Plus, add-ons like battery packs and solar panels also increase the price.
- Charging: How do you plan on charging your power station? Are you mostly going to use AC power from an outlet, or do you want the independence of solar?
- Battery Chemistry: Lithium-ion (Li-ion) is the traditional battery technology, but the newer lithium iron phosphate batteries (LiFePO4) are safer and have a much longer lifespan.
