Portable Solar Power

This one has a 4000 mAh battery, so holds more charge. Left in a tent that lets quite a bit of light in through the fabric, it seemed to charge itself about 1/2 way a day:

Amazon.com: Opteka BP-SC4000 Ultra Thin Solar Powered High Capacity (4000mAh) Backup Battery and Charger for Cell Phones, iPhone, iPod, and Most USB Powered Devices: Cell Phones & Accessories

At approx. 4.7 oz., it's pretty portable and light and small enough to be reasonable for backpacking even. Keeps the phone running and my phone works better as a gps than my 2 dedicated gps units, + does a bunch of other stuff.
We would like to begin camping again this summer, but haven't done any since before our children were born. Please advice how to determine the best choices for our investment. We need 1 with a lot of room and at least room for an air mattress. We would prefer 1 with multiple rooms option but do not want poor quality. Anyone know anything about Turbo Tents? Any advice- will be great.
The problem with these little pocket solar chargers is that they almost always under-power the solar.
A little math...
These products usually have a solar module capable of between 1/3 & 1/2 Watts. In full sun. So, in the case of the first product mentioned, it would take approx 12 hours to fully charge its internal battery (not the 8 as it's specs state... sorry Chinese manufacturers, but the numbers don't add-up).
In the case of the second product mentioned in this thread, the battery is a lot larger, and so it will take almost 24 hours of full sun to charge it. Note the reviews on the product page... most of them complain about a full day of sun, and barely anything of the battery charged.
NOTE: in non-optimal exposure, the rule of thumb I use for portable solar is 3 peak-sun-hours per summer day. Meaning that a 1/2Watt panel will produce approx 1.5 Watt-Hours of power. This is approx 1/4 of an iPhone battery for example. Do you use more than 1/4 of your phone battery in a day?

The first product has a 6.5WHr battery, and the second has almost 15WHrs. That means approx 4 days to fully charge product #1, and approx 10 days to charge product #2. You don't have to fully charge either product to use them of course.
You can also do better if you leave the charger outside at the perfect angle in full summer sun, but that defeats the portable utility of the product.

Sorry for the lecture, but I don't want to blow any smoke up your skirts when talking about what these products can & can't do.
They make great back-up batteries (product #2 offers great capacity!), but the solar is a novelty at best.

When shopping for a portable solar charger, I recommend drawing the line at 1W at the very least on the solar panel, and if they don't tell you, then figure that 1W requires approx 20 sq-in of solar cell. 1W solar with 8WHrs of battery storage will give you some practical, sustainable power for a phone or GPS.

Feel free to email or reply to this thread if you want my opinion on any specific product. I won't spam, so I won't make product recommendations unless they are asked for.

Hmmm...I've wondered about some of that stuff, but didn't have the background to know for sure. Thanks for the post. I have had mine charge from 1/4 to 3/4 (roughly as there are 4 lights on the Opteka unit I referenced above to give a rough idea of the battery charge) full just leaving it in the tent (the TipiTents I make use a very thin, lightweight fabric that lets quite a bit of light through) for the day when gone. Seems like it has worked pretty well for me on several trips. It starts charging automatically when placed in enough light. Now, before a hunt, I typically just through it in a south facing window to 'top it off' before leaving. At this point, I'm pretty happy with it.

I've got a friend with a much more powerful unit that we use when on multiday, open ocean, sea kayaking trips, but it weighs a great deal and is quite large. Certainly not something I would backpack hunt with.
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