Voltaic Solar Battery Charger

What to do when you are out in the field with amazing scenery to shoot, a handful of exhausted camera batteries, and no electric outlets in sight? Self-disembowlment comes to mind, but wait, there are better options. I was recently on an 18-day Grand Canyon rafting trip and faced with the above dilemma. One option I utilized was a small waterproof solar charging system from Voltaic. The unit I tested was a beta version as far as the waterproof housing went, but other than the housing, it used the components of Voltaic’s 17 Watt Solar Charger Kit ($265 MSRP).

The Voltaic system uses a 17-watt solar panel to charge a storage battery, in this case Voltaic’s V72 Laptop Battery. You then use the storage battery to charge your camera batteries or you can also charge camera batteries directly off the panel. As well you can charge camera batteries off the storage battery while the solar panel recharges the storage battery. The storage battery can also be charged from AC or your DC car outlet – both convenient ways to charge the storage battery before heading into the wild. The storage battery is no bigger than a slim paperback such as Brighty of The Grand Canyon, my reading for the trip (the mostly-true tale of a heroic burro – ages 8-12).

Using the Voltaic kit was very simple, just plug a battery cradle into the V72, slip your camera battery into the cradle and in a couple hours you camera battery is charged. When the V72 charge dips, plug the solar panel in, point toward the sun and let the battery pack recharge. Note you will need to get the appropriate DC-powered battery cradle for your particular model camera battery (the charger you get from Nikon, et.al. is probably just AC-powered) – this does not come with the kit, but you can easily find such cradles through Amazon, etc. The only control to set is the 12/16/19 volt switch to give the proper output to the cradle.

Does it work? You bet. Voltaic rates the V72 battery as being able to charge 3.5 DSLR batteries before you need to recharge the V72. In practice I actually charged 4 EN-EL15s (used in D7000/7100, D600/610, D750, D800/810) before needing to recharge the V72. I may have exceeded the specs because these batteries were run down to one bar, not to the blinking red “oops I’m screwed” state, before I removed and recharged them. I’ll just say I’m usually dubious of claimed capacities on battery-driven items, so I was happy when the V72 lived up to its hype.

The panel that charges the V72 is fairly stiff and measures 15.5”x 10.75”x 0.25”. I took reasonable precautions to protect it from damage. If you got careless and stepped on it I don’t think it would do too well, but for minor bumps it seemed plenty rugged. Line drop is a big issue for solar systems, so the cord between the panel and battery is kept short.

The waterproof housing kept the battery dry, but was too big for the battery. As stated above the waterproof housing was a beta version and Voltaic plans to use a different housing in future kits. Hopefully the new housing will have a pressure relief port as the one I tested didn’t and I could see air pressure blowing it open if it were submerged more than a few feet underwater.

In practice in the depths of the Grand Canyon, this system didn’t crank out as much as I hoped. This was not the system’s fault, but due to a combination of inclement weather, the depth of the canyon and the twisting nature of the Colorado River, which constantly brought us in and out of shade as well as switching the orientation of the panel strapped to the raft. By the time we got to camp, the sun was often low in the sky. It takes the panel ~7 hours to fully charge an exhausted V72 battery and we rarely got that many hours of direct sunlight to devote to solar charging. I could only get the V72 charged up to 3 of 5 bars while in the Canyon, but after the trip successfully got it charged to all 5 bars by using best practices – unobstructed midday sun and the panel angled at right angles to the sun. Even at 3 bars I could get two EN-EL15s charged, so it kept me in business. According to Voltaic, 2 hours of sunshine are sufficient to charge one DSLR battery – this seems to agree with my results in the Grand.

For a Grand Canyon trip, other charging options exist. You can pack a pair of deep cycle marine batteries with an inverter (total weight over 100 pounds and if you are a heavy battery user, you might exhaust all your juice – these kits rent for $8/day, not including the hernia operation). Alternatively you can bring enough pre-charged camera batteries you don’t run out (big bucks, unless you go the AAs in battery grip route – I estimate I ran through 15 – 18 charged batteries on my trip, but I’m a heavy shooter – don’t forget a lot of memory too). Generator use to charge batteries is not allowed in the depths of the Grand.

The Voltaic can also be used to charge smartphones (7 charges per full V72) or a laptop (one charge per full V72).

Without months/years to test this system, I can’t comment on long-term durability and battery life.

The Bottom Line

In the right conditions – abundant sunshine with the solar panel directed properly – solar charging is a viable option to keep you shooting when no electric outlets are available. Efficiency drops way down in inclement weather or if the panel gets shaded. Don’t wait to charge your DSLR batteries until they are all exhausted – take advantage of every sunny day to keep your stock charged. Size your system to take care of your needs plus a bit more. I like that the Voltaic system I tested was relatively compact, lightweight (~3 pounds), simple to use and lived up to its published specs.