Is the new FTL Solar Powerfold Charging System the best backpacking solar panel on the market? The answer is probably yes, but we still need accessories.
Backpacking is a sport where ounces count and the choice of what to take with you is often determined by which version of the same thing weighs less. If we had anti-gravity packs or robotic burros I’m sure we’d all carry different kits, but for now we wait for stuff that’s better and lighter. You can’t get away from those two essential qualities, even if you’re like me and carry some extra pounds because it’s fun stuff. Cutting down the weight of other gear leaves me room for the fun stuff.
Update 2/17/2012: Powerfold products are currently unavailable on Amazon although I’ll leave these ads running in case they return. A similar solar panel, much more versatile and user-friendly, can be found through this post about New Solar Panels That Actually Work.
Over the years I’ve waited for several innovations to arrive and I’m still waiting for most of them. The Lightning Pack, an electricity-generating backpack frame which converted waste movement to electric power, fizzled after a brief run in the press. Konarka, a firm developing lightweight solar panel fabrics, finally announced one product for the consumer market but very little information is available as yet and I haven’t found it for sale anywhere. But at last, somebody with high-tech promises is coming through with a full range of real products that aren’t limited to industrial or military customers. FTL Solar, Ltd., now markets several versions of high efficiency and lighter weight solar panels for everyday users, with two of them in the weight range a backpacker might actually consider.
The idea of solar panel chargers has always been tempting, but previously if you got into the math and figured out how many panels you needed and what charging gear you had to add to make the system work, unless you were planning to live in the Outback for a few months it was cheaper and more weight-sensible to take extra batteries. Solar panels on products like the Eton Scorpion Weather Radio are functional dead weight, because they can’t even keep up with the power drain of the unit in full sun. Crank chargers made more sense for emergency cell phone backups because you don’t have to wait around for a couple of days of good weather to make them work. Those of us who would like to go as green as possible still had to consider what makes sense. Extra rechargeable batteries made the best sense, not solar panels.
FTL’s PowerFold 5 and PowerFold 10 promise to be different, offering useful power output levels from a device just barely within the range of weight sensibility — seven ounces for the Powerfold 5 and 14 ounces for the Powerfold 10. The single-panel Powerfold 5, 7.5 inches by 16.5 inches and only .25 inches thick, provides a very impressive 18.94 VDC at .26 amps and the Powerfold 10’s folding double panel generates the same voltage with .52 amps of output current.
At the moment, this is the best you can get in lightweight solar backpacking panels. According to FTL Solar, the National Resource Ecology Laboratory (NREL) of Colorado State University rated the FTL Powerfold panels as producing the most watts per size.
Hooking them up to rechargeable batteries may be the only trick. The output connection is an SAE plug, so unless you have a device which accepts that you’ll have to figure something else out. Although FTL says a wide range of accessories are available, I haven’t found them yet. FTL says you shouldn’t use the panels with lead-acid batteries unless you run the output through a charging controller. Controllers limit the voltage level across the battery and prevent overcharging problems which could include explosion and fire. Recharging lithium batteries presents similar hazards without a customized charging system, which is usually part of the device if the battery is built in. Charging heavier types like ni-cad or ni-mh requires a charging station, not included with the solar panel.
So it’s a mixed blessing at the moment — the panels are here, but we’re not quite ready for them. Waiting on parts . . . .