BigBlue 28W Solar Charger Foldable with Digital Ammeter

The bad news: the highest charging current I've had in ideal conditions (Scotland, midsummer, midday sun, clear skies) is only 1.7/1.8A. A long way short of the maximum suggested by the manufacturers. The good news: 1.7A is an extremely useful charging current. The Big Blue can also pump out some solid current on overcast days - close to 1A with light cloud. Obviously really heavy cloud will drop the output to zero. In mixed weather conditions I found it more than capable of keeping phone, headtorch batteries etc charged on an extended camping trip. My phone gets used pretty heavily - photography, news & weather if I can get online, Kindle books etc - so this was a solid performance. I also used a couple of 18650 batteries and a Nitecore F1 charger as a lightweight buffer for the rainy days when I couldn't deploy the panel. On sunny days there's charge to spare to fill up the batteries. The 3 stars for water resistance is just my best guess. The unit seems to cope OK with a smattering of rain but I wouldn't want to get it really soaked. The panels seem to have a waterproof coating but I doubt very much if the main electronics, under the display, are waterproof. Why does water resistance even matter for a solar panel? In showery conditions the Big Blue can gather a lot of useful charge in the bright spells. A fully-waterproof unit could be left out unattended while you get on with something else. That's the bottom line for portable chargers: do they fit seamlessly with daily life in the field or does it feel like device-charging is starting to dominate your time? The Big Blue performs well enough not to be a nuisance. The display is great - indispensable really. If you want to learn how best to use the panel you need to see how well it works in different conditions. I measured the weight at 610g on scales of unknown accuracy. All in all, I like it. May not perform as well as claimed (I didn't really expect it would) but it does perform well.

I've had this a month now and have tested it in all sorts of weather. I have to say, although I was worried it wouldn't be too great with the British weather, it has surprised me... a lot! I've provided two examples below of my experiences where the charger was on the dash of my car (on sunny days I folded the output screen under the panels with the windows ajar). I also only charged one item at a time. Very cloudy/rainy day with no direct sunlight: When it first arrived in March, the weather was miserable but I was still able to get a reading of 0.2 to 0.4 amps. So I plugged in an iPhone and it began to charge! However, rather than leave my phone in the car, I plugged in my small power bank and left the panels on the dash of my car. I thought that the windscreen would filter out some of the required rays but I had the same reading in and out of the car. Anyway, I came back to the car that evening after it rained all day and the sun was low in the sky as its still late winter/early spring. The bank was half charged and is 4000mAh, so for pretty much the worst type of weather (no direct sun at all the whole day) for solar and the sun only being low in the sky anyway, I think it did well. I was able to fully charge this bank after two and a half days of this same weather. My 8000mAh power bank never reached full charge and obviously took a longer - 4 days but the 4th was spent stuck at 75 to 100%. Sunny days: Wow. This thing is great in the sun! the maximum output I've achieved is 2.2 amps, and that was on a bright sunny day at the beginning of April. It charged my 4000mAh bank in 3 hours and I've left my 8000mAh bank in the car which was charged completely by the time I'd finished work - I'd left it from 10am where the reading was 1.6, checked it at lunch time and the reading was 1.9 to 2.1 and then in the evening at 5pm when I finished work, the reading dropped to 0.2 with the sun being very low and the angle of my car not being great either. However, the bank was also showing as fully charged. I've also found that the last 15% or so takes way longer to complete, I'm no expert but it just seems like its harder for the solar charger to push in that final bit of charge! On sunny days it will manage but on other days I settle on 90% and switch to another empty bank. It's also worth bearing in mind that I choose to charge power banks still rather than plugging directly into my iPhone because if it takes say a day to charge it and it's still switched on, then you're going to need a sunny day to get it close to 100% because not only are you trying to charge up a 1821mAh battery, but you'll be using half of the supplied power to power the devices wifi/cellular/screen/background processes etc. An iPhone and some other devices also require a minimum amount of amps, so when its cloudy for a while and it's 0.4 on the solar charger, your phone/device might reject this and cut it off. A power bank generally doesn't so this power(although a small amount) is still soaked up. The only thing that does annoy me about this solar charger is that the USB ports are difficult to access from within the pocket - it's not a big deal, maybe something BigBlue can improve on in the next model. Very happy with my purchase.

Sometimes this seems to charge my power banks quite well, and on other apparently sunny days it struggles to add much juice to the bank. It's better than the previous version which on "sunny in parts" days would actually drain the power bank completely rather than charging it. But it's not something I've been able to rely on to add power. Nice when it works : disappointing when it doesn't

I love it. I used it on an EBC trek to charge my power bank, and it was amazing. It is definitely charging, and you can attach it to the backpack. It is simple and packable. I like it.

Best buy ever. First test at sunny midday in south of UK and I got 3.9 amps from both ports, I couldnt believe my luck. One was 0.6 and one 3.3. I thought the max output on one port is only 2.4 but wrong. Next time only had my powerbank plugged which accepts 5v 3a input and got 3.3 amps like on picture. Thats a fast charge, over 16W of power. Great great panel, probably the best. Also on cloudy days I do get 0.5-1amp of current so 2.5-5W of power, not bad, not much many other panels can pull out any power from cloudy days. Well worth money for it

I love this. It's as good as you can expect from current solar technologies. Runs at about 2.5A in bright sunlight but significantly less in shade. I charge my power pack during the day and use that to charge my devices at night. I bought this for wild camping and it certainly serves that purpose - folds up relatively small, relatively light weight. And it hangs from my backpack on charge during the day (although obviously the angle not always optimum!). Highly recommended if your needs are similar to mine.

I bought this in Dec for my charity hike and seems to work OK for a while but I'm not having any output at all now, not had many sunny days so not used it often and quite looked after, not sure if I had a bad one as seemed to be an OK solar panel

I was pleased I got my big blue for £70.00 but after a month of occasional use i has packed up.At first I was impressed with this device it charged up two of my B&M Goodmans 10,000 Mah batteries from flat to full in 5 and a half hours but one month after receiving it the unit falls to work at all so not a good use of 70 pounds in my opinion.The display reads zero output and the battery display is not flashing as it does when charging so this solar panel has failed.

Werkt uitstekend. Op een wisselend bewolkte dag heb ik 0,3A tot vol in de zon ongeveer 2,7A met soms uitschieters van 3,0A in Nederland. Powerbank van 20.000mA ging van 67% naar 100% in 3 uur tijd vol in de zon (buiten temperatuur 26 graden Celsius).

Quality product. Easy to use. I get 2A current a sunny winter day in the middle of Sweden. Light cloudy and I am down to 1.5A. A medium cloudy day about 1A. That means that I should get 3A in the summer and promised 4A further south. Not bad. Everyone should have one of these at home. Highly recommended.

Good charger however very slow. Good for backup.

Compré este cargador solar para situaciones de emergencia en las que no dispongamos de suministro eléctrico, decir que la sensaciones son buenas, ya que los materiales se ven duraderos, aunque en algún comentario y es cierto matizan que la unión entre los paneles solares tendrás que cuidarla, ya que quizá es la zona más frágil a la hora de manipularlo o colgarlo, dicho esto me imagino que en condiciones de uso normal y cuidadoso debería durar bastante. Por otra parte, y como comentan también en otros comentarios, la potencia real no son 28 W sino 20 a la hora de cargar, pero este tipo de dato es igual en todos los paneles solares nunca vas a tener la potencia que publicitan en la mayoría de los casos. Independientemente de este pequeño dato respecto a la potencia la carga, es muy buena cuando sitúas el panel solar correctamente en el ángulo adecuado, ya que eso marca una diferencia muy grande en cuanto a la potencia de carga, en mi caso yo lo compré con el amperímetro para poder visualizar la potencia de carga, según lo colocara, lo cual me parece muy útil. Para los que no lo sepan la carga a través de un cristal o en el interior de una casa, reduce considerablemente la potencia de carga de cualquier panel solar, por lo que no será igual que si lo cargas en exteriores, evidentemente si tienes una terraza un jardín, no te supondrá ningún problema y si no, simplemente tendrás que esperar más tiempo si lo cargas en el interior de tu domicilio o a través de un cristal, evidentemente te sacará de un apuro igualmente ya que puedes cargar directamente el móvil a través de dos conectores en tiempo real que es la función de este cargador solar. No te recomiendo meter los dispositivos que cargues en el interior del bolsillo, ya que se pueden llegar a calentar mucho dado el color del cargador solar y que estaría directamente expuesto al sol, por lo que te recomiendo que una vez conectes el cable de carga, el dispositivo intentes dejarlo a la sombra o en una zona donde se recaliente lo menos posible.

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