I’ve been seeing a huge number of ‘gadget’ solar chargers on the market this year. Everything from keychain size up to devices larger than your hand. Personally, I think this is fantastic, and am glad to see so many alternative energy products making it into the retail realm. But all these gadgets can make buying a pocket solar charger seem like a daunting task. Fear not! This article will get you through the forest.

It’s a fact that many of these products are not built very well, and many manufacturers cut corners. And if a Chinese factory cannot secure an OEM contract with a recognized North American brand name, they tend to dump their wares on Amazon. Some are good, but most are garbage.
But should you trust a pretty picture, and statements about charging digital cameras & phones faster than a wall charger?
How can you spot the good ones?
Well, apart from always checking ModernOutpost.com, use the following 5 questions to guide you when buying a pocket solar charger…

1. Is the solar panel the thin-film variety?

Thin film doesn’t require direct sunlight, while crystalline does. So thin film solar cells will provide a charge in most weather conditions. A thin film solar panel will outperform a crystalline panel of the same power rating any day of the week. Less efficient, but far more effective!
If they don’t tell you, then it is safe to assume that they don’t care, and it is likely the cheapest form of crystalline they could find, and not worth your dollars.

2. What Is The Solar Panel’s Power?

Pocket chargers like to quote the capacity of their battery pack, or confuse you by telling you that they can pump out 2100 mAH from their USB port. All very good, but how quickly they charge from the sun is the key spec they don’t always tell you.
Look for a panel of at least 2 Watts… this is large enough to cover 50% of a smartphone battery April-Sept.
A 2W crystalline panel will be approx 5″ x 5″ in size, while a thin film panel will be twice that size.
If they don’t tell you what the solar power is, maybe you shouldn’t buy it. You wouldn’t buy a camera without knowing the sensor size, or a bike without knowing about its gears, would you?

3. Battery Capacity?

Look for at least 4,000 mAHr, or you won’t get even 1 full charge on a Samsung Galaxy or iPhone 6.
Lithium-Polymer (LiPo) is lightweight & reliable, and now we see Li-NMC from the electric car industry making its way into smaller solar chargers.
DO NOT purchase any solar charger that uses NiCd batteries as its storage.

4. Pass-Through Charging?

This is an important one. Pass-Through charging means that your solar gadget is able to charge your phone or camera at the same time it is charging itself. This seems like an obvious point, but a huge number of USB batteries & solar gadgets don’t do it. Imagine having to wait until your solar charger gadget is almost full before charging your phone, and while charging your phone, not being able to collect the sun’s energy (or even use the USB port)!
This is a must-have feature!

5. Apple Compatible?

You might not have an Apple product, but you should care if your solar gadget supports Apple.
Why?
Because if the manufacturer has taken the time to ensure that the USB port is fully functional, and able to support the fussiest of personal electronics, it is far more likely to be a product that you can rely on to charge any USB device.

These are my top-5 tests for small solar chargers. Only if they pass these tests will I then compare the winners based on cost per Watt, Watts per gram, durability, and other metrics that are important when using this type of equipment away from civilization.

Send me a note if you want my opinion on any particular product you see online.
Cheers!