Anker 21W 2-Port USB Solar Charger

Anker 21W 2-Port USB Solar Charger


Anker 21W 2-Port USB Solar Charger at a glance

Portable solar chargers are becoming as popular as they are inconsistent. The Anker 21W 2-Port USB Solar Charger does a good job of squashing many concerns that other manufacturers may be responsible for spreading. High quality, American made cells coupled with clever design choices make this one of the best portable solar charger power banks on the market.

  • Intelligent design
  • Exceptional customer service
  • SunPower solar panels
  • Max Wattage unrealistic
  • Panels are affected by interruptions in light
*Check out the Anker brand page here.

Capacity & Charging speed

There is a bit of controversy as to exactly how much efficiency you can expect from solar devices like these. A product claiming 21W can do close to this under near-perfect conditions. The reality is, even with Anker’s 22%ish efficiency rating on their cells, I wouldn’t expect more than 13-14W output at any point.

To their credit, they offer PowerIQ technology (explained somewhat in this review) and pretty fast charge speeds to your device of choice. With 2 USB ports, they can offer a maximum of 3 amps output at any one time which is impressive. Impressive if you have a lot of sun.

We found that the Anker 21W 2-Port USB Solar Charger works well under hot, humid conditions and can simultaneously charge 2 smart phones at once. Do be careful though, the Anker 21W 2-Port USB Solar Charger will not charge the following devices: iPod nano, iPod Classic, iPod Shuffle, HP TouchPad and Asus tablets.

We also found in a few cases that it wasn’t reliably compatible with some higher capacity power banks and portable chargers.

Look and feel

The Anker 21W 2-Port USB Solar Charger has 3 solar panels encased and separated by a meshy canvas. The panels fold into themselves nicely and the product generally feels well made. There are 2 stainless steel eye holes on each corner-end of the product and 2 more on the third panel down. This is great for hanging from a tent, a tree – anywhere really, be creative!

Straight out of the box, the Anker Solar Charger Power Bank comes with an Anker 3ft Micro USB cable, welcome guide, and an 18 month warranty.

Durability & Construction

A product like this is begging to be taken camping so it needs to be durable. Just as importantly, it needs to work and be consistent. We found that in some cases, the Anker 21W 2-Port USB Solar Charger did not like to be moved around too much. A shadow or a passing cloud would seriously affect the output of the device and it would take a while for it to get going again.

On the plus side, when it worked, it worked great. The solar panels are from a high quality manufacturer made in the states and are protected by industrial-strength PET polymer. The canvas that separates the panels is rugged, durable and water resistant. Like any solar charger however, we recommend not leaving it out in the rain. Chances are you aren’t getting much charge at a time like that anyway though right?

It also comes with Anker’s standard short circuit and surge protection technology to help protect your devices.


We love the design of the Anker 21W 2-Port USB Solar Charger. It folds away beautifully and is quite thin too. At 11.1 x 6.3 x 1.1 inches, it’s a little bigger than you might imagine from the pictures. With that said, it’s very easy to carry around with you and is worth the extra bulk.

The fact that it’s flexible and extremely light makes it a great addition to any outdoorsy activity.

Technical Details

Manufacturer Anker
Size 11.1 x 6.3 x 1.1 inches
Weight 14.7 ounces
Type Solar Charger
Max Wattage 21W
USB ports 2
Colors Standard

Final Thoughts