Technaxx 21W Solar Charging Bag TX

Technaxx is a German company that operates in a number of areas. From the game camera to the Internet radio to solar systems and mobile batteries, the range is wide. And it is developed in the Hessian town of Schöneck. And since solar systems can be built in a wide variety of sizes and shapes, we find ourselves testing the Technaxx 21W Solar Charging Case TX-207 in the small range. The 21W in the name also stands for the maximum charging power of the mobile power generator for devices with USB charging. How the quality looks like and what this mobile charging bag is suitable for, I take a closer look in this test.

Inhaltsverzeichnis / Table of contents

The Technaxx 21W Solar Charging Case TX-207 comes in a sturdy but simple cardboard box. When you open it, you look directly at the Technaxx TX-207 charging case. Underneath is the multilingual manual – and that's it for the scope of delivery.

The box is very simple and can easily be sent to the paper recycling. Incidentally, this follows the shipping box, which here also came with a paper delivery bill compartment instead of the usual plastic. The trend at Technaxx is obviously towards sustainability.

Cables are logically not included. Since you have to see anyway, which cables you need for the devices to be charged.

Flat, clean, black: the Technaxx 21W Solar Charging Station is compact and simple-looking at first. The format is somewhat reminiscent of a foldable seat cushion when hiking. When closed, it is held in place by a full-width Velcro strap. When unfolded, it consists of four sections. Three are of these are solar panels and the last is a small pocket with USB ports and a small velcro strap. There are also two metal rings between the section with the pocket and the solar modules, as well as on the last solar module. These can be used to attach to hooks or with straps, for example.

The small pocket that holds the USB ports is secured by a small velcro strip in the middle. At most, I would transport the (connected) USB cables here, but not place a smartphone. On the one hand, not because of the heat that a black surface can reach in the sun. On the other hand, not because this compartment is so small in itself that my smartphone and case barely fit inside. I would also assume that would not be the intention behind this case. That said, I would also like a light-colored version of the Technaxx 21W Solar Charging Case TX-207, which should probably heat up less in the sun.

So the "charging bag" in the name is probably less about the bag function, and more about the fact that the overall package can be packed into bag form while protecting the solar panels.

There is not much to say about the workmanship of the Technaxx 21W Solar Charging Case TX-207 in this review, as it shows virtually no weaknesses. The fabric is solid, the seams clean. And even when I threw it over some surfaces and dragged it at test time, it didn't result in any damage.

The manual asks to be careful to connect only dry equipment and to keep moisture away. The only recommendation left is to not take any chances here and keep the Technaxx 21W Solar Charging Case TX-207 out of harm's way when it rains. Even though I doubt that this will lead to quick damage, you can't expect to get a particularly productive output together at this moment anyway.

I find the position of the USB ports in the small case a bit awkward. If they were a bit deeper in the bag, connected cables would be less likely to come into conflict with the Velcro. Speaking of Velcro, a small cable fell out of the USB pocket during testing because the Velcro is quite short. Found it again, but it's a shame when cables neither loose nor connected fit perfectly in the small bag.

What limits the Technaxx 21W Solar Charging Case TX-207 in particular is that it "only" charges via USB at a maximum of 6V. This is not a problem in principle. So, for example, smartphones, tablets, Bluetooth headphones or speakers, small powerbanks or similar things can be charged with it. Even bicycle lights can now be partially charged via USB, which can be quite interesting in mobile use. However, for some devices, such as modern laptops charged via USB, the charging voltage will be too low.

Still, the concept is quite cool. While the Technaxx 21W Solar Charging Case TX-207 is mainly intended for mobile use, there's nothing stopping you from using it in your everyday life at home. Yes, the savings may be minimal to charge a couple of mobile devices by the sunny window instead of the wall socket. Also because, in all likelihood, the charge will only run at full speed when the sun is at its best. But once you’ve decided to invest, why not take full advantage of it? But let's get to the real point….

The Technaxx 21W Solar Charging Case TX-207 has the advantage of being compact and lightweight, so it can almost always be packed away. This makes it suitable for multi-day trips that make it necessary to charge his mobile devices. Be it for multi-day bike tours where you need navigation, or simply in principle for the universally used smartphone. And thus it is also practical when camping, where either in the tent or even in the detached camper can quickly run out of power.

When hiking, for example, you will often have your smartphone in use for navigation during the day and here it is less practical to directly connect the charging case that you can attach to your backpack, for example. Here, it makes sense to use a powerbank that you can charge during the day and then use the charge to charge the smartphone in the evening. A direct charge is nevertheless more efficient overall.

Yes, the attachment to the backpack is also a thing. You can use a strap, carabiners or rope to attach the Technaxx 21W Solar Charging Case to your backpack, but in doing so, the small pocket with the USB ports is virtually always open at the bottom. In fact, if you use the rings on the solar panel side as the "top", the compartment with the USB ports will hang down accordingly. If you use the other side for hanging, the end with the USB ports is behind the rings. So you can either fold it onto the first solar panel, which would affect performance. Or you can fold it the other way behind the solar panel, but even then the opening faces down. It's also clear that you don't want to put the cables over the solar panels, so a 180° rotation wouldn't be an optimal option, but here I would have preferred an opening to the side. Or two more rings behind the USB compartment.

Positives: The Technaxx 21W Solar charging case TX-207 is in this case also an additional sun protection for the backpack. Thus, the transported drinks do not warm up so quickly. However, it becomes a bit more fiddly to open the backpack.

What I also miss a bit, that is a way to stand up the Technaxx TX-207. A small stand on the back could help to point it towards the sun without looking for a way to lean it against anything. Sure, if the sun is beating down almost vertically from above in the summer, you can just lay the Technaxx 21W Solar Charging Case TX-207 on the ground. Otherwise, you can also put it down completely by bending the individual sections. But with the overall already not too high energy output, it would be nice to be able to aim it more specifically.

At this point, I would like to start by expressing a bit of my irritation: If the maximum voltage is 6V and the maximum current is 3V…. wouldn't one have to end up here purely mathematically with a maximum power of 18 W instead of 21? The most I can imagine is using both USB ports, so that the calculated 18 W is the maximum power of one port and when using both ports the maximum voltage is reduced by distributing it to both ports.

But good. For the measurement, I put the free Android app Charge Meter into use. This shows the current amperage while charging, which is displayed with a slight delay and updated regularly, indicating how fast the mobile device is charging. And no, this app does not belong to Technaxx, but it is handy in this case to be able to evaluate the effect of the placement of the solar cells almost live.

Here it can be seen: Even when it's cloudy, power is still generated – albeit far less than when it's sunny. Moreover, clouds are not all the same. When the sky is dark gray, almost nothing happens. Likewise, there are different intensities of sunlight. The flatter the sun's rays, the more of its power is lost as it travels longer through the atmosphere. So you can't just say how long what takes to charge. For example, the Technaxx 21W Solar Charging Case TX-207 took a full day to fully charge the Tronsmart Bang SE from 20% in a sun-cloud mix.

Clearly, you have to approach the Technaxx 21W Solar Charging Case TX-207 with the right expectations. 21W achieved in the rarely reached optimal case is just not really that much. On the other hand, it is light and compact to transport and can ensure that the smartphone or powerbank is charged anywhere, independent of the power grid – and again, there are hardly any better solutions for this. In addition, there is the good workmanship. Sure – I would make a few changes according to my personal taste. But from a practical point of view, it has to be said that the Technaxx 21W Solar Charging Case TX-207 is an extremely useful piece for (bike) hikes, camping, power outages or other unexpected situations.

Small, light and mobile: The Technaxx 21W Solar Charging Case TX-207 is a very cool solution for charging smartphones, powerbanks and the like in the sun. You just must not have unrealistic demands on the power.

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