View Full Version : solar power when hiking

12-27-2008, 21:52
I was in REI and I saw a small solar panel that you put on your pack. I was wondering if any one has used this and if so could you use it to charge your Ipod or cell phone?

12-27-2008, 22:15
I have not used one, but from other posts it sounds like they are not that great due to the trail having heavy foilage coverage. I have not yet read a post giving solar chargers a good review for the AT. Maybe the REI one is more efficient, but if you are in the shade all day it still won't work well.

12-27-2008, 22:34
You may be right didnt think about the shade and for $100.00 I want to see what people had to say about them.

Johnny Swank
12-27-2008, 22:59
I don't think it'd be very good for the AT (shade, mostly). You'd probably be better off with one of those AA battery backup things, or just carry/bounce the charger and be done with it.

AA Battery Backup Charger (ttp://www.amazon.com/gp/product/B0010OCOAY?ie=UTF8&tag=sourctoseapad-20)

FWIW, I'm a big fan of not carrying anything that doesn't use either AA or AAA batteries for just this reason.

Christus Cowboy
12-28-2008, 00:32
I've looked at the solar option myself but if you're under a heavy canopy of trees it really underperforms by what I've read..... I started looking at this option to help me in a pinch......


12-28-2008, 02:24
Hey snowhoe, there is another option, When i was in a pinch for a recharger i came across a doo-dad on ebay all it basically is is a battery box that has the ipod cable end wired into it , all you do is put fresh batteries inside plug in the ipod like normal and turn the little switch to "on" it took like 4 AA batteries but i could get atleast 2 FULL charges from the ipod being all juiced out,

Cranking charger Pros---

Free energy

Compact form,lightwieght

Cranking charger Cons---

takes ALOT of cranking at a steady pace to create enough current

Can be noisy as you crank it up

Might have to spend more money on a special ipod/special phone cable to connect to that particular charger

Battery pack Pros----

No cranking, just plug it in turn it on and let it charge

can use rechargeables to keep from buying batteries in each town

no noise

Battery pack Cons

slightly bigger than the crank charger

Batteries add wieght ,however little

if you choose to use rechargeables there is the added cost and time spent buying the super fast recharger (some i have seen charges 8AA in 15 minutes), as well as cooling your heels where ever electricity is to charge them up again, if you can find a place

if you dont use rechargeables added cost of new pack of batteries in each town

12-28-2008, 08:34
this topic has come up several times in the two years I've been here. No one has reported resounding success. It seems like there were a few luke warm sucesses.

Main problem was lack of direct sunlight IIRC


12-28-2008, 10:05
Captain very interesting I think I will check into the battery one sounds kinda heavey but might work. thanks

12-28-2008, 11:22
I'm sure this has all been said before, but solar chargers simply don't have enough amp output to quickly charge a device. Even at peak output in full sun, it could take many many days.

As for crank chargers--

I've got a nifty little generic crank charger with a 5.6/6 volt output. Roughly one minute of cranking gives you five minutes of cell phone time. This one is relatively compact, and even comes with a radio, a free flashlight and, er.... a siren. With all the attachments, cables, bells and whistles, and etc. it weighs in at 191 grams. For the ounce weenies, that's 6.7 ounces (exactly the weight of Wingfoot's Thru-Hiker's Handbook, btw). With some clever modification, I'm sure you could cut another ten grams... No, I didn't buy the thing, and no, I don't carry it, but it's an option.

Personally, I'd ditch the IPOD and get a simple mp3 player that takes AAA batteries.

For the cell phone-- considering the cost, weight, and efficiency, it might be more effective to carry a spare battery pack and bounce a charger.

The battery pack idea which was mentioned seems like a nice way to convert a system to conventional battery technology, but it seems like a bit of hassle to me. It's all about choices....

12-28-2008, 12:12
I've not done the AT, but on the PCT this year I found a solar charger (Solio) to be a good augment to recharging in trail towns or other places I could beg a little power from (for example, charge at a little store while I'm eating ice cream). I had just one device to charge (smartphone) but I used it for a variety of things (phone, journal, camera, voice recorder, book reader, GPS), so keeping it charged was occasionally a challenge, mitigated by carrying one or two extra batteries for it.

For most of California I found the solar charger to be a no-brainer worth carrying item. For Oregon and Washington it was mostly not worth carrying, even though recharge opportunities were farther apart there. I'd thus be inclined to agree that it makes no sense on the AT, given reports of both lots of overhead canopy, and trail towns quite close together.

Seems to me that a person could just carry an extra battery or two for whatever device and recharge in towns and be done with it. As Captain said, a battery pack is an option, though if I recall correctlyat least some battery pack manufacturers recommend using lithium AA's, which provide more power and are lighter, but are also expensive. Perhaps put one in your bounce box and carry only if you foresee a no-power stretch coming up that makes it worth carrying.

Hand crank units: there might be something credible out there, but I own one and wouldn't consider carrying it on a hike. IMO there's a big difference between getting a minimal amount of charge to be able to make a short emergency call, and being able to really recharge my device on a regular basis.

What I would suggest instead is limiting your electronics to things that take a standard battery type where possible (headlamp, camera, phone, whatever else you might have), and if you're into trading $$ for weight, see if you can find a lighter weight recharge cord if that's an issue. The power cord for my smartphone is at least 2 ounces heavier than another power cord that I happened to have for an MP3 player --- I was lucky in that both deliver the same charge via the same (mini USB) tip, so I carried the lighter one.

Get a little aggressive in asking if you can charge your device at restaurants, gas station mini-marts, etc. A couple of times on the PCT this year I found that the campground bathrooms had electric outlets. I'm not normally the type of person to ask favors of strangers (thru-hiking changes you ...), but most people said yes when I asked them to charge my phone.

Brian Lewis / Gadget '08 (PCT)

Lucy Lulu
12-28-2008, 13:06
I used a BB Curve this year on the PCT, and carried a Solio charger. In S. Ca, I could get a full charge in 2-3 days in constant, direct sunlight. I found though, that for the BB, two back-up batteries weighed less than the Solio charger, and took up far less space in the pack. In WA and OR, the Solio was not much use, and it went home.

The challenge, as mentioned in earlier posts, was keeping these batteries charged. It would typically take me one hour per battery with the device turned off. This was not too much of an issue since I never had a restaurant tell me I could not charge it. I also was able to charge it in PO's while I repacked, convenience stores...most anywhere allowed me that had an outlet.

I really only used the BB for journaling on the trail, so I only turned it on briefly throughout the day if I stopped for a break. This allowed me to use a battery for about 3 days, as long as I did not use the phone or internet, and kept it off most of the time. I would often have an unused battery when I hit town.

12-28-2008, 13:14
Looking over the selection of solar chargers at REI, the one I would pick is the Ice Tech solar i-9005. The main reason is because it has a charge level indicator and auto shut off to protect the internal battery. These two features are lacking on most solar chargers and with out them, you 1, don't know how much charge is in the internal battery and 2, if you discharge the internal battery too far, it can damage it and will no longer take a charge. Unfortunetly, this charger can't be tied to the outside of a pack too easialy.

Most of the solar chargers I've seen claim about 10 hours to charge the internal battery from full discharge. This is 10 hours of direct, noonday sun so in practice, it takes a lot longer. However, if you don't wait too long between chargings of your phone or whatever, you don't discharge the charger too much and is quicker to get it back to full charge with the sun. Which can be done during lunch and other rest breaks. Even so, I'd have an AC charger along to top off both the battery in the solar charger and in the phone/other device when in town.

12-28-2008, 14:38
I made my own solar charger from a solar yard light. The light was purchased at Home Depot for $25, it was the type with an adjustable 3 AA battery pack with the solar panel on the top of the pack. I removed the light, a little minor re-wiring and done.

On the AT it does not work very well due to the lack of sunlight but this last year in the Alps it worked very well with 8 batteries keeping my camera and GPS working for two weeks. It worked in the Alps because there was a lot less tree coverage.

Wise Old Owl
12-28-2008, 15:24
I honestly think you need to check the customer reviews at REI for the best yea or nah and I found this on their website - this was the $79 version that only works in direct sunlight

Here was this little gem of info....................Copied from REI


By DVC4045 http://www.rei.com/pwr/engine/images/pixel.gif from Idaho on 5/26/2008
Charges slowly, Lacks Power, Will not solar charge, Inconsistent Performance

Best Uses:
Paper Weight

Describe Yourself:
Quality Oriented

Primary use:

Bottom Line:
No, I would not recommend this to a friend

I bought this to use on my 2009 AT thru hike, but it only works as a pricey battery. 30 hours of sun light (80+ degrees out and no clouds over 3 days) produced a 40% charge. It works great as a battery if you charge it off a USB port first, but if you have a handy USB port you probably don't need it. After talking to the manufacture I was told it could take 5 days or more to charge, assuming there are no clouds and you keep it oriented at the optimum angle towards the sun. The 6 hour charge time qouted is for USB charging. Needles to say this is not coming with me in 2009.

12-28-2008, 21:05
snowhoe if you would like im willing to send you mine so you can see if you like it before buying one. that way you can experiment with it and see how it works for you

12-28-2008, 22:33
As it has been stated elsewhere, solar chargers seem to work best in stationary locations where shade is not a problem. On most of the AT, there is too much shade (even in the wintertime with the leaves off of the trees, the shade caused by the overhead branches can cause problems). Above treeline, the results may be better. (Of course, cloud cover is another factor that will affect performance.)

Solar power seems to be a poor option for most of the AT.