Solar Charger?

Most of the talk is about this these days.

http://www.suntactics.com

If you looking for something with build-in storage as well, I used this on the JMT last year: http://www.amazon.com/Bushnell-Bear-Grylls-SolarWrap-Charger/dp/B00AMPJNT2/ref=sr_1_1?ie=UTF8&qid=1422852164&sr=8-1&keywords=bushnell+solarwrap+mini

HTH

KJ

You will never get anywhere with proper sizing of a solar charger until you can predict your power usage. You want to charge a phone and a camera? Quantify that.

You need to predict the capacity, such as 1000mAH, that you need and for what period, such as daily or weekly. Nobody else can predict how much you use these items.

Plus, you have to predict how much sun you will have. If all of the days are cloudy, then no solar charger will work.

–B.G.–

I like to add a question to this thread, if I may… For those who own solar chargers:

Say you have a small point and shoot camera and a smart phone. You also have a "backpacking size" solar charger that's "typically efficient" for this day and age. How much daylight do you need to charge a device to the point where you can use it for at least a few hours? Assume a summer day — with decent (but not blazing) sunlight from mid morning to mid afternoon.

I ask because my hunch is that solar charging is "not practical" for a hiker or traveler who is "on the go" — that you really need to set the thing down and facing the sun for at least a few good hours to really charge anything… Am I correct or have portable chargers really improved???

In my opinion, there is no definition for backpacking size, and there is no definition for typical efficiency. Nor is there any definition for typical sun. The farther you move from the Equator, the more difficult this becomes. You can still solar charge at Barrow, Alaska, but the sun angle will provide some challenges.

There are reports from several backpackers who are able to pause on the trail, like for lunch, set up the solar charger, store up some solar wattage, and repeat that during each day. If they keep their power usage very low, they can sort of keep up with it.

There are reports from backpackers who do not have that patience, so they try to collect solar charge while on the move, so to speak, with their panels hanging on the sunny side of their backpacks. I think that is tricky and unpredictable.

There are more reports from slower backpackers, or those who take lots of zero days. In that case, they are able to set up the panel in a perfect spot and let it do some serious recharging for hours and hours. I think this method works best, especially for those who are consuming lots of battery power. But you may not have all that time in a busy schedule.

The opposite case is true for short trip people. If you are going to be away from AC power receptacles and other charging systems, you are better off (weight-wise) by simply carrying one or two spare batteries and no panel.

–B.G.–

> my hunch is that solar charging is "not practical" for a hiker or traveler who is "on the go"

Well, I kept my batteries fully charged for a couple of months in the Pyrenees with a small panel on top of my pack. Steripen and camera.

Of course, if you want to run 20 W continuous of power for 8 hours every day, you might need a slightly larger panel.

Cheers

"Well, I kept my batteries fully charged for a couple of months in the Pyrenees with a small panel on top of my pack. Steripen and camera."

Hi Roger:

Can you tell us the model — and whether you had the charger regularly set up stationary — or hung on your backpack and on the move? More detail greatly appreciated. Thanks.

Guide 10 switch 8 combo worked well for me on the JMT. Heavy at 10oz, but I used my phone a lot for pictures, ebooks, and even audio books while hiking. It sat on top of my ULA circuit and charged my HTC one too full almost every day, despite lots of usage.

I have used the Goal Zero Nomad 7 with the Guide-10 (4xAA) battery pack. The Nomad 7 can charge a device through a USB port or charge an accessory like the Guide-10 via it's 12V output. The USB port has a slow charge rate and you have to have your device plugged into it during the day for it to charge. I opted to charge the Guide-10 battery pack during the day (in 2-4 hours) and use my phone for photos/video. At night, I'd plug the phone into the Guide-10 and charge from that.

I think the Guide-10 with 4-AA batteries is heavier than the Switch-8. If you only need to charge USB devices, then use the Switch-8. If you also have other devices that use AA batteries, then the Guide-10 might be more flexible since you can pull out the AA and insert them into your AA-battery devices. The Switch-8 wasn't available when I bought my Goal Zero several years ago.

In reading up on various solar panels, I found that while some are cheaper, they may not work that well unless in full sun. Other ones like the Goal Zero seem to work ok even in partial sun.

"I have used the Goal Zero Nomad 7 with the Guide-10 (4xAA) battery pack. The Nomad 7 can charge a device through a USB port or charge an accessory like the Guide-10 via it's 12V output."

Exactly what I have. The only big reason to have the 12V output is for a camera battery charger. My camera battery charger needs 12V since it is charging up a lithium battery of a nominal voltage of 7.4V.

For short trips, I don't carry the panel. I just carry some spare camera batteries. For a trip when I am going to one spot to hang out for days of sunny photography, I take the panel.

Single crystalline solar panels tend to cost more and have higher efficiency, but I don't think that it is by much. Additionally, the opposite (amorphous silicon) is what you find in flexible solar panels.

–B.G.–

Hi Ben

It's the panel off a Steripen charger, about 150 mm x 100 mm, and maybe 5 years old now. Pretty generic silicon I think.
It sat on top of my pack while I was walking each day, pointing more or less upwards.
I never bothered setting it up when stationary – at lunch time my pack was open, and in the evenings there ws no point.

What really matters is how bright the sun is. On a clear summer's day in the mountains, there's lots of solar energy.

Cheers

This is planning stage only, but I figure a Suntactics sCharger-5 (no battery pack) will work fine for me in high Sierra. It's advertised to charge at 1000 mA in optimal sun, and high Sierra is pretty close to "optimal" much of the time. I'm only going 12-15 miles a day and not at all adverse to a nap after lunch, so setting up in noon sun for 1.5 hrs is not a problem for me.

Needs:
Sony Camera Li-Ion NP-BX1 battery (USB in-camera charge): 1240 mAh; charge daily
iPhone5 (used only as book reader): 1440 mAh; charge rarely
Bosavi headlamp: 700 mAh; charge rarely
SteriPen Freedom: 1000 mAh; charge very rarely

The camera is the only thing I expect to discharge daily, and in theory that can be fully recharged in 1.2 hrs on sunny day lunch break. I'm not sure how many hours that equates to strapped on my backpack while hiking south with a big hat, but I'll do the experiment just for curiosity sake. If it clouds over for days I'll just have to limit my photography.

My understanding is that the iPhone is probably the most finicky item for charging without battery pack due to being too "smart" to handle intermittent charging. Given my minimal use of this item, I don't see any need for separate battery pack. I don't know yet from experience but I believe other USB-chargeable battery devices can charge under less optimal conditions.

I was looking also at Goal Zero Nomad 7, but the main advantage there was availability of 12v, which I don't need due to camera I presently expect to rent (probably Sony RX1R which has same battery as R100's). Other than that, the Suntactics sCharger-5 seems to edge it out both for weight (8.4 versus 12.8 oz., manufacturer spec) and, at least in my searches, thru-hiker reviews. On the other hand it is $50 more expensive.

The Bushnell SolarWrap is smaller capacity and very cheap and you are buying a fixed battery pack with the panel. It gets pretty hammered in reviews, but I suspect that is mostly due to users expecting more from it than it could possibly deliver.

Edit: On charging 7.3v camera batteries or AA/AAA from USB, has anyone else tried the Pixo Universal Charger? (http://www.goalzero.com/p/161/pixo-universal-charger-for-cameras) I picked this up before Christmas when they had it for $10 with free shipping. It successfully charged my SLT camera battery (Sony proprietary 7.3v Li of some sort) from wall-mounted USB, but I haven't timed it carefully from full discharge nor paired it with solar panel yet. It's kind of moot for me now after I decided to rent compact rather than take my 54 oz camera.

del

Thanks for the link Rick the comparisons are very nice.

Right now I have a GoPro and a regular camera. I have 3 batteries for each camera. That is enough for normal trips but I hope to do a 10-12 trip this summer so I'll need more juice.

The two lighter choices would be the Instapark Mercury 4S or the SunTactics. I can't find the figures on the Instapark Mercury 4 but the SunTactics 5 claims to charge a GoPro battery in 2-3 hours. On a good day I could probably get close to that in Wyoming but it might take some effort.

So theoretically I can charge a GoPro battery every other day and keep that going and a regular camera on off days and keep it going. Seems like just enough…

If I want to be really safe I have two (heavier) options. First I could get the Mercury 10 which is 14 oz (ouch) but charges two things at once. Or could add a battery pack to one of the above smaller chargers. I think the main advantage here would be that I could be grabbing solar energy even if all my batteries were charged AND it would be power available for either camera.

Any thoughts?

On the site "Kit Up" I saw an article about the Marines testing a solar charger panel B/C they want to lighten the spare battery load for the soldier who, like many backpackers, carry increasing numbers of electronic gadgets.

Lessee:
1. Olympus TG 1 camera
2. Garmin Colorado GPS
3.iPod Nano
4.Princeton Tech headlamp

AFTERTHOUGHT: Yeah, I could live without the GPS and the iPod but the camera gives me so much pleasure later when I see my photos as a slideshow wallpaper. Plus it's the lightest good camera I've ever owned, and that includes the original Olympus OM-1.

"My understanding is that the iPhone is probably the most finicky item for charging without battery pack due to being too "smart" to handle intermittent charging."

Exactly. I am on my 3rd iteration of DIY charging, and devices vary on how well they play with solar cells. As the iPhone is terrible, I use a charging device as the intermediary "charge controller." The Fasttech charger is picky, the Anker battery and Steripen much better. This year I got one positive first-hand PCT-thru report of the Suntactics with the iPhone, and have read others, so at 8 oz for 5 watts the Syntactics would be my purchase if I needed something more reliable and off-the-shelf. I hope that there can be more community effort at reducing the solar charging overhead in the spirit of DIY UL backpacking.

We used a Suntactics sCharger-5 for a couple months traveling by canoe. And now I use it in the back yard to charge my phone. We're happy with it.

In full sun it charges the iPhone at about the speed of a wall charger. We set it up for an hour while we eat lunch or after stopping at camp. If we several consecutive cloudy days we got more conservative about using the phone for discretionary stuff (bird guides, Wiki Offline browsing, etc). It worked well for us.

We also used it to charge the camera battery and the battery for the Marine Radio (while canoeing). There's a super handy little thing you'll want for charging batteries of assorted sizes. You can find it at Amazon:
"Universal USB Clip Charger for use with 3.7V Li-Ion Batteries By Lenmar"

Most camera, radio, and Android batteries will fit, and the clip plugs right into the Suntactics solar panel.

Amy

Please keep us updated on the Clip Charger and how it holds up in the long run.

Also, do you have a weight for the clip charger? Might make a good lighter replacement for what I have already: http://www.amazon.com/gp/product/B00P91ALHM?psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00 and http://www.amazon.com/gp/product/B00FDUVPKG?psc=1&redirect=true&ref_=oh_aui_detailpage_o06_s00

TIA!

KJ

I also have the "Universal USB Clip Charger for use with 3.7V Li-Ion Batteries By Lenmar" and it works a charm for charging camera batteries. You do have to pay attention when you plug it in to the solar panel USB port as it is easy to put it in upside down – which obviously doesn't do anything for charging. The clip has a tiny green LED that is difficult to see in direct sun but does indicate a proper connection.

Ken, The Lenmar Clip Charger weighs 0.3 oz. We've had it for a couple years and have used it for a few months total. As Bob mentioned, it's kind of delicate and a little fussy, but it is cheap and light and it really does work with a wide variety of batteries. Make sure you master it at home before you head out — you want to know what the red and green lights mean, and you want to know which orientation to use when you insert it into USB port on the solar panel (or wall charger).

Amy

Is the clip charger capable of charging batteries that only have the contacts on the narrow end/side of the battery?

KJ

Does anyone have any tips for mounting a Suntactics on top of their pack? I just got the sCharger-5. I ran paracord through the corner holes, but my first attempt was uselessly loose. I'm sure others have already found optimal solutions.

Ken – the distance between the contact points is adjustable from 4 mm to 20 mm. And the spring loading mechanism that holds the battery in place expands to about 18mm. It's hard to imagine a camera or phone battery that would not fit.

Their little video illustrates it well: https://www.youtube.com/watch?v=IyjkTfUBJz4

http://www.voltaicsystems.com/solar-panels

This should be the answer to every question asked here. It took some searching but i found Voltaic, and they have solutions for just about everything. Panels, batteries, connections for everything known to man, at a very acceptable weight. I dont use a battery, i direct charge my cr123 batteries, crappy cell phone, and mp3 player. So that is often an option. Ya, check em out, they even have little mounting screws on the corners, so you can bolt the panel to your pack if you like. I bolted a 2watt panel to the lid of my pack and i can charge two flashlight batteries in a day of less than optimal sunlight.