Solar Powered Charger

I'm not sure if this is the proper place to put this. Mods, please move if it is in the wrong place.

So, I've been wondering what mobile photographers do to keep their phones charged up while they're away from any stationary charging locations (power receptacles, car chargers, etc.). I've been looking at some solar chargers online and read some reviews and feedbacks and haven't been convinced that this is the way to go just yet. As with most new technology there is a high failure rate with these things.

I've looked at 300,000 mAh to 30,000 mAh chargers and they all come with a disclaimer saying that they actually charge to around 18,000 mAh. So right off the bat there's some hype in the advertisement. However, some of the reviews and feedbacks I've seen say they are as good as a 1,500 mAh charger. Going WAY below the actual charging capacity in MANY cases.

Some sellers on eBay even make note of that capacity and say that you can get 3-4 charges from it when it's fully charged. If it's solar powered then you should be able to charge the charger when the sun is up. Then charge the phone at night. But the feedbacks I'm seeing there are not favorable towards these charging devices.

On the other hand I am seeing lots of positive feedbacks on these devices as well. So decisions, decisions. I may take the plunge and order one of the waterproof ones I've seen.

Heya,

Solar chargers are fine. It's the battery setup that matters with them. Basically you use solar to do long chargers into a larger capacity battery (think deep cycle battery). You use that battery to recharge your devices. It will have tons of juice to recharge your phone, batteries for cameras, etc. When you're stopped some where you just throw up the solar panels and slowly recharge it. The battery will be big and heavy, but if you need enough juice to go quite a long while and the means to slowly recharge it, that will work. A lot of people do this for portable observatories and RV's, etc. It works.

Very best,

So I assume your out hiking away from any power source. The trouble with solar chargers is that they work when the sun is up which is also usually the time your hiking. When you set camp for the night, the sun is gone and your batteries are dead.
Another option is getting a hand crank generator. They are cheap, reliable, and can be used anytime. There are both the small, USB type good for phones and such, or larger ones that you pedal capable of 120 vac.

Ad for 30000mAh unit, but with 'real' 12000mAh rating...where do these guys get factors for TIME?

Marine suppliers of solar chargers for boats rate their products in mA or A, but leave out the time factor. After all, we might only have full sun and the panels exposed at proper angle to the sun for 5-6 hours per day. If the panel cannot be at right angle to the sun, like at 45 degrees to sun, its efficiency drops to 70%. Unless you put your phone and solar panel on the ground all day, it is not really going to get much suitable exposure even on your back. which is not the same as mounted all day on the top of an RV. And even then think about what fraction of time is with sun overhead at more than 45 degrees...6 hours during summer?!...as I write this, it is 8:35am and the sun is still at avertical angle of less than 45 degrees

Then there is the shading factor, where a panel's full sun rating is much less efficient in less than ideal conditions. A light overcast might drop it from full sun 100% down to 70%, and heavy overcast to 25%.

IF a product claims that it can provide 5V at 1A current, and do so well enough to charge a phone for 6 hours, that is 30000mAh, but it is storing electricity into its own battery in order to make such a claim.

gjl711 wrote in post #18095182
So I assume your out hiking away from any power source. The trouble with solar chargers is that they work when the sun is up which is also usually the time your hiking. When you set camp for the night, the sun is gone and your batteries are dead.
Another option is getting a hand crank generator. They are cheap, reliable, and can be used anytime. There are both the small, USB type good for phones and such, or larger ones that you pedal capable of 120 vac.

The one I was looking at actually has a battery in it. You charge the battery in the device then you use the battery to charge your phone.

Something similar to this...

http://www.ocm.com …bybroduf6r5ibk2​g5sp3c.jpg

You charge it up, then you can (supposedly) charge your phone 3 - 4 times from a fully charged device.

Solar charging stations are usually rated in W (power). mAh doesn't make a lot of sense. At least that's the way they sell you solar cells over here in Europe. For hiking, you typically buy a 5W or 10W module at a certain voltage (typically 5 V or 12 V).
Just to give you an idea about the energy you need to charge a LP6 battery (7.2 V, 1800 mAh = 12.96 Wh of Energy). You loose about 20% for charging the LP6 directly from the Solar cell -> 12.96*1.2 = 15.5 Wh. With a 5W panel you theoretically need a little more then 3 hours to charge your battery.

BUT: The rating is for standard situation (1000 W solar energy per square meter, vertical on the cell and 25 °C). In reality you never get that. Either it is way less then 1000 W/m2 (Arizona full sun) or then it is way above 25 °C and heat decreases efficiency substantial or then the sun is not vertically above the solar cells. Additionally, the ratings are similar to battery ratings. Very often they are substantially off. Additionally, if you have an other battery pack in between, then you loose an other 20% for charging this battery.

In practice this means, the example above takes 2 - 5 times longer - even if you have your pack exposed to sun - depending on where you are and what quality solar pack you have.

My conclusion was, that for most temporary uses you are better off with a large power bank.

CameraMan wrote in post #18095132
So, I've been wondering what mobile photographers do to keep their phones charged up while they're away from any stationary charging locations

My question is how many times will you have to recharge your phone before you're at an outlet again?

Battery backups can be fairly inexpensive and work very well if you get a quality model. I use a Sharkk brand 10,000mAh battery that has two put put jacks (1A and 2.1A). I can get about 4-5 recharging out of it no problem. Like I said, if you do go that way get a QUALITY brand. Stay away from the cheap Chinese eBay crap ones as they will really embellish the mAh ratting.

charging a phone by solar is doable, couple cool fold out solar panels on the market. Slow and impractical is key word.. Also there is a gas stove that charges usb..that said..I do a lot of motion control work in the field and could never carry enough panels to be effective so a generator is on my list. I use a deep cycle and can charge cameras, laptop phone and a number of 10000mAH before it dies..works out to 80000mAH. I have it setup as a second battery in my car and it wasn't charging properly (lasted a full weekend in the field before dead..) also take into account that an inverter will also suck up a bit of that resource.

I bought one. It charged my phone twice so far (while it was left on), I've charged a speaker and my iPod one time as well. I'm pretty sure the charger caught some sun rays a few times since charging it fully the first time. I'm pretty happy with it at the moment.