Timinator
01-17-2014, 01:13
So I came across this http://www.voltaicsystems.com/fuse6w.shtml recently and I was kind of impressed with the design. Further research shows that they make quality stuff with good customer service (I even had a long email chat across several days with a customer service rep, he was very patient and helpful with fast response times).
Has anyone ever used anything from voltaic? They seem like a good alternative to goal zero and I can't get over the convenience of their "fuse" panel design.
Im sure that one works fine but its pretty bulky and heavy.
I would look at the suntatics Scharger5
http://www.suntactics.com/product/usb-scharger-5/
Stumpknocker used a solar panel while hiking the Florida Trail last year, and seemed to have good results. Here is a link to that journal,
http://trailjournals.com/entry.cfm?id=396298
kayak karl
01-22-2014, 21:42
i have this one on my kayak deck. http://www.voltaicsystems.com/3wattkit.php i recharge my New Trend 5200mAh with it.
I don't have any experience with portable solar chargers, but I will give a few thoughts on them anyway.
It looks like iPhone 5 battery is 1440mAh, so the Voltaic battery should give you over 2.5 full charges. I'd consider myself a medium phone user and I generally don't burn through a full battery over the course of a day. Searching for a signal can really burn through a battery, but if you keep your phone on airplane mode for most of the day (HYOH and all, but I don't see why you wouldn't turn airplane mode on), you can really save on battery life. So let's assume with music, photos, and occasional email/text/gps you get two days out of your phone. This gives you 5 days of battery life without even charging battery pack.
The relationship between shade and PV efficiency can get pretty complicated, but the gist of it is that shade is bad. If you want detail http://sargosis.com/articles/science/how-shade-affects-a-solar-array/ has a good explanation. I'll try to summarize it quickly. In partial shade, a solar panel's current will drop, so less electricity will be going into your battery, slowing your charge time. In full shade you will get no electricity. Conversely, if you have something blocking your panel (like a leaf, or dirt, or a strap), your voltage will drop and your batteries won't charge. Further, in changing shade, the inverter will struggle to keep up and may not deliver the max power.
All of these numbers correlate to a pretty specific set of conditions and you will not get their rated efficiency while on the trail. Anytime there is a reduction in irradiance (total sunlight hitting your panel) you will see a drop in efficiency. This can be due your panel not facing the sun (it won't be if you are hiking), it is cloudy, you are under foliage cover, etc. Additionally, heat negatively affects the efficiency.
I think these panels have a use in the back country, but I do not believe they are useful for thru hikers who are only off the grid for a few days at a time and are rarely in a good location to take advantage of solar power. For less weight and less money you can get a battery pack. Heck, at that weight you can get a very large battery pack (http://www.amazon.com/New-Trent-PowerPak-14000mAh-Smartphones/dp/B00GK745L2/ref=sr_1_9?ie=UTF8&qid=1390536487&sr=8-9&keywords=new+trent). Will a solar panel charge a battery? Yes. But there are cheaper, lighter and simpler ways to do it.