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Are there any feasible solar chargers for iPhone / or with a usb slot that will work or is a backup battery available. Best value (and something that works) is my priority. I found this brilliant link on crazy guy on a bike- However, since then I came accross 'portopow' - which look great but I can barely find any reviews.

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closed as too broad by jimirings, freiheit Mar 17 '14 at 0:59

There are either too many possible answers, or good answers would be too long for this format. Please add details to narrow the answer set or to isolate an issue that can be answered in a few paragraphs.If this question can be reworded to fit the rules in the help center, please edit the question.

There are solar chargers and backup batteries. But this is not a shopping site, so you should go somewhere else for recommendations. – Daniel R Hicks Mar 6 '14 at 12:15
There are also dynamo chargers. – PeteH Mar 6 '14 at 15:21
up vote 4 down vote accepted

I have actually used both 2 different sized solar panels and a lithium backup battery on Ragbrai. Whether any of these will work for you depends on:

  1. How many days long is your ride?
  2. How sunny will it be and how much time will you have to do a solar charge?
  3. How many devices you need to charge.

For solar charging. The first lesson is you can not charge your device with a solar panel while you are riding. Solar panels need to be pointed directly at the sun to provide any kind of real power. The little solar chargers you see advertised are utterly useless. They might charge a phone if they were pointed directly at the sun for an entire day (15 hours). The larger solar charger I have is 14" x 12" with an adjustable mount so you can keep it aimed at the sun. I could recharge my phone (when off) in 4 - 5 hours.

Small charger (useless)

10 watt panel (works)

What worked the best was a large backup battery. They are not physically large- just large capacity. (15,000mAh or more). I used this for an entire Ragbrai. It charged my phone once a day for 9 days with power to spare. Note you turn your phone off at night, plug it into the charger, and the charger automatically turns off when the phone is charged. The phone saves power by being off all night. Wake up, turn the phone on and it's good for the entire day and evening.

Sample 15,000mAh battery

You can fly with these batteries in your luggage and probably in your carry on luggage. But the TSA often makes up its own rules on the fly and might decide to confiscate one in your carry on. I would keep it in checked bags.

TSA rules

Note that it takes about 2 full days to charge one of these batteries. You should probably test charging all your devices at home to see whether you can make it on your trip. You also need to remember that your battery is just as dangerous as an equivalent sized container of gasoline. You do not want to puncture it or expose it to high heat.

If all that information is confusing, I only take my backup battery on Ragbrai now.

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TSA actually recommends that you pack lithium containing batteries in your carry on bag to better monitor them since Lithium batteries have been known to catch fire so they'd rather have them where you and flight crews can keep an eye on them. Though they don't prohibit them in carry-on bags. – Johnny Mar 7 '14 at 5:32
Yay, actual experience! My experience is similar, FWIW, and I now have a 5W panel, fibreglass-enclosed, with built in 5.1V USB MPPT. So I just plug my phone in and leave it in the sun. Charge time is a couple of hours, so I normally charge at lunch and then leave in the the sun when I stop at the end of the day. – Móż Mar 7 '14 at 7:01

Check out GoalZero, they make a bunch of portable solar products. While it's a little bit pricy they are quality products that will last. My buddy uses one when we are gone racing and have no access to electricity, and it works quite well for phones and other small electronics.

I have also seen, but don't really know much about, people putting these on their hydration pack while they ride (just don't crash).

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At the time of this posting, the solar chargers out there aren't very robust, unless money isn't a factor.

If you're going to be camping each night, try the biolite camp stove. I haven't found anything that can charge my iPhone faster and it's relatively cheap, much cheaper than a good solar charger.

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what an excellent idea! – PeteH Mar 6 '14 at 18:34
Does that stove really work well as a charger? It's rated for 2W continuous power output (4W peak), which is less than a computer USB port, so it must take well over an hour to fully charge an iPhone. That's a long time to keep the stove burning, plus the stove weighs over 2 lbs. If you have some way to expose it to the sun (on top of panniers?) seems like a small 5W - 10W solar panel would be lighter and less effort so you don't have to keep the stove burning for hours every night. The 7W GoalZero panel mentioned in another answer is $79, vs $129 for the Biolite stove. – Johnny Mar 7 '14 at 5:24
I've never had to wait longer than an hour for the biolite to charge my iPhone, and even if the 7 watt capacity solar charger is faster, you can't use it at night when you're normally sitting around needing to charge your phone. – hillsons Mar 7 '14 at 6:16
Do you have any experience with solar chargers? – Móż Mar 7 '14 at 7:01
man, it's so cool! I think I'll buy one immediantly. – constpetrov Mar 11 '14 at 13:19

To weigh in my experience, I did the US Southern Tier last summer and did not need solar chargers. I did consider them, though. My requirements were to keep my Nexus4 on 24x7, while GPS tracking my route. This is a pretty power intensive application, and I was able to do it by just buying a big 15,000mAh backup battery and charging it whenever I had access to power. I could go for about 4 day in between without any power before I had to plug in, and even going through the desert this was not a problem. YMMV.

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Do you have any recommendation for the battery and can you take that on a plane :) – Andrew Welch Mar 6 '14 at 17:43
I bought the highest capacity Anker battery I could find and it was around $70. I don't see why you wouldn't be able to take it on a plane, as laptop batteries are of similar capacities. I took mine on a domestic flight with no problems. – Booker Mar 6 '14 at 20:40
@AndrewWelch: The TSA uses grams of "lithium equivalent" to determine what's safe to bring on board. The upper limit of 25g for carryon equates to around 300 watt-hours of battery capacity. For a 5V USB battery pack, that's around 60,000mAh. – Johnny Mar 7 '14 at 19:36
I'd say even if you use chargers (a hub dynamo in my case) you're better charging a battery and using that to charge other devices, it handles intermittent charging better, and simplifies your connector needs. Also, a dedicated GPS (eg Garmin) uses way less power than a phone to do that job. Use the phone intermittently, it lasts ages that way and is there for emergencies. – bazzargh Mar 18 '14 at 11:35

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