are lifesavers during a blackout, easily keeping your phones, laptops and routers fully charged. But what happens when you need to power something much larger, such as your fridge or washing machine? Many people assume they need to drop thousands of dollars on a whole-home battery system just to keep their food from spoiling.
To test that theory, we brought 19 large and extra-large portable power stations into the lab and hooked them up to a standard refrigerator. Our testing revealed a surprising truth: You don’t need nearly as much wattage as you might think. In fact, depending on your energy draw, a smaller, budget-friendly station is often more than capable of handling your heaviest home appliances.
The Fossibot 3600 Pro performed the best overall, keeping the test refrigerator running for an impressive 44.65 hours (1.86 days). The Oupes Mega 5 followed closely behind in second place at 43.72 hours (1.82 days).
The Oscal Power Max 2400 had the shortest runtime by far, lasting only 12.58 hours (0.52 days).
The Anker Solix F3800 Plus performed poorly for its size, lasting only 25.68 hours (1.07 days) despite its large 3,840Wh capacity.
The Bluetti AC200L unit is the efficiency king for large appliances, lasting 29.27 hours on a 2,048Wh battery.
The Anker Solix C2000 Gen 2 is a standout performer, lasting 27.4 hours on a 2,048Wh battery.
CNET’s lab testing gives us reams and reams of data that let us determine the most efficient portable power stations across every size category. Our winners for round-trip efficiency, which measures how much energy you get back from the power station compared to how much power you need to draw from a wall outlet to charge it, are listed below.
For charging speed, which measures how quickly a portable power station can charge to 100% from empty, we have only one winner.
How CNET stress tests portable power stations for disasters
Each of the 19 portable power stations in our test batch was used to power a full-size refrigerator (Whirlpool, 60Hz, single-phase, 118V, full-load 7.2A) until the battery completely drained. We measured how long each unit kept the refrigerator running and reported the results measured in hours and days. Since this test reflects real-world use rather than a controlled laboratory measurement of battery capacity, efficiency ratings (round-trip efficiency) are only reported from our standard testing procedure.
While the results showed that larger units last longer for demanding appliances, they also revealed that slim, custom-designed models such as the Bluetti FridgePower prove you don’t need huge, bulky home backups. In fact, several of our better-performing models weren’t what we consider “extra-large,” ones with a capacity larger than 2,200 watt-hours, but rather fell in a more modest 1,300 to 2,199Wh range.
Unique measurements we use for our fridge stress testing
The total usable capacity the battery has available to give.
The actual amount of energy the refrigerator consumed over the duration of the test.
The difference between the measured Wh and the fridge Wh. This represents the energy the power station consumed itself (idle draw) just to keep its inverter running for that amount of time.
The delta divided by the measured Wh. This gives us the exact percentage of the battery’s total usable energy that was wasted as internal overhead.
Below is our list of power stations, ordered by how long they kept our test fridge running.
As seen in the combined list below, while the units with massive XL battery capacities generally sit near the top, highly efficient large units, including the
can outrank several bigger systems (such as the Anker Solix F3800 Plus and Pecron E3600LFP) simply because they waste far less energy.
The extra-large models naturally dominated the absolute runtimes, but performance varied widely by efficiency, with the
being our overall winner for both sheer runtime and efficiency at 44.65 hours (1.86 days). In the large category, while they have smaller batteries, the top large units proved incredibly power-efficient, with the Bluetti AC200L as the overall winner, delivering 29.27 hours of fridge runtime (1.22 days).
Jackery Home Power 3600 Plus: 38.58 hours (1.61 days)
After testing eight, there’s only one extra-large portable power station we recommend for fridges
Jackery Home Power 3600 Plus: 38.58 hours (1.61 days)
The Fossibot 3600 Pro is our top choice for keeping your fridge running.
The Fossibot 3600 Pro is the best power station for keeping your fridge running. It kept our test fridge running for 44.65 hours (1.86 days). That means you can get almost two days of cooling during a power outage if you own the 3600 Pro. It’s also remarkably power-efficient. Even though the Oupes Mega 5 had a much larger measured watt-hour (4,352.86Wh compared to the Fossibot’s 3,293.74Wh), the Oupes wasted an incredible 1,730.22Wh just to keep its inverter running.
This resulted in a 39.75% reduction in efficiency fo