BERNET 24000mAh Review
Cons: Battery slow to charge, solar cells cover small area, heavy
Our Analysis and Test Results
If the battery is fully charged, the Bernet 24000mAh panel works great. It is fast, efficient, and charges devices with ease. Unfortunately, it takes a while for the battery to charge, as the panel itself is so small. The size makes it easier for the Bernet to get obscured by shadows, further reducing its efficiency. In general, we found this panel to work better as an external battery than an actual solar panel, which is par for the course with panel designs such as this.
Charge Interruption Recovery
This metric is a difficult one to test, as the panel performs significantly differently when the battery is charged vs. when the panel is solely relying on its solar panel for power. When we tested charge interruption recovery, the panel had a bit of charge left in the battery, making it one of the top performers in charge interruption recovery. The battery charged our test batteries from 0% to 3% in the first ten minutes and proceeded to charge another 1% over the course of the next ten minutes of intermittent sun. The fact that the panel still charged the battery is due mostly to the fact that the internal battery can make up for losses during an interruption of sunlight. We experienced similar, yet less effective results from the iClever BoostCel 12W.
Phone Charging Speed
Both in the 30-minute charge test of an iPhone 6 and in our race to charge an external battery, the Bernet worked very well, when the battery was fully charged. We do not advise trying to charge any device off of this battery unless it is already fully charged, as the panel itself is not very powerful. When it was fully charged, and in the sun, the panel excelled by charging an iPhone 6 36% in 30 minutes. This is on par with the top contenders in this category (the Anker PowerPort 21W and the PowerGreen 21W). The results are impressive, but it's important to remember how powerful the 24000mAh battery is, in comparison to the 10W panel.
Multiple Device Charging Speed
The 24000 panel is the only one in this review with three USB ports. This is relatively noteworthy since it is only a 10W panel. What this feature says about the Bernet panel is that the battery is powerful. With the battery fully charged and it's in full sun, it charged two batteries up to 2% from 0% in 30 minutes. This is better than nearly all other panels in this regard, though the more powerful models, like the Anker PowerPort 21W and the PowerGreen 21W excel since they are more powerful overall. As a battery alone, the Bernet works excellent charging multiple devices, but relying on solar will not produce enough power to charge more than one electronic device at a time.
This panel is pretty heavy, with the solar panels exposed, making it questionable concerning durability. Its weight makes it easy to drop, and an impact could result in damaging the solar cells themselves and even the battery inside. These factors gave the Bernet a lower score regarding durability. We preferred the Renogy 5W to the Bernet for a small capacity panel, mostly due to its durability. The iClever BoostCel is also a better option in terms of durability because it is much lighter and the battery itself is hidden behind the folding panel, protected by a layer of canvas.
Weight & Portability
Regarding weight and portability, the Bernet also falls a bit short as well. The panel is bulky and heavy, with a look and feel that is more in line with an external battery than a traditional foldable solar panel. The Bernet weights more than all the other panels, minus the iClever BoostCel 12W. There is no way of attaching the panel to a bag or backpack, unlike the iClever BoostCel 12W, which has a more traditional panel design as well as an incorporated battery.
Additionally, there's no way of standing up the panel, other than leaning it against something. This limits the locations in which you can set it up to get the most direct sunlight. Even the more substantial panels, like the X-Dragon 20W panel weigh less than the Bernet, and have more impressive charging capabilities.
This contender is best used first and foremost as an external battery and secondarily as a solar charging device. The battery is strong and works well to charge multiple devices quickly, but the product lacks the surface area of solar cells to make it an efficient solar device. We found that the panel worked well when the battery was charged, but it was difficult, if not impossible to charge a device and replenish the battery at the same time using solar power.
This charger originally held a price tag of $100, making it no small investment. However, you can find it on Amazon now for around $40, which we find to be a reasonable price for such a powerful and efficient battery.
The Bernet 24000mAh panel/battery combo works best as an external battery, and less well as an actual solar charging device. It is nice to have the option of using solar, but the panel is so bulky and heavy, it seems hard to believe that one would carry this thing too far from a power source. That said, the panel charged our devices efficiently and no glaring flaws or finicky issues were found.
— Jane Jackson