Voltaic Systems Arc 20 Watt Portable Solar Laptop Charger, 24,000mAh | Includes Foldable Panel, USB-C PD Battery Power Bank and 2 Year Warranty | Powers Laptops Including MacBook

I'm very impressed with Voltaic Systems and their products (and also their tech support). I bought the ARC 20 system (20W folding solar array and V88 power bank). Also the USB-powered Touchlight. Delivery was quick and easy to track.I had a couple of questions about the hardware, and submitted those via Voltaic's support page; before the end of the day I had a friendly, helpful, and knowledgeable response.The products themselves look and feel rock-solid. I bought the Voltaic products instead of other, cheaper alternatives primarily because of the many product reviews from photographers, journalists, Peace Corps volunteers, and others who clearly have put these products to real-life use in some difficult environments and who were uniformly pleased with the performance. I was not disappointed when my devices arrived: this is clearly "professional grade" hardware, not the cheap stuff.Just to satisfy my own curiosity, I fully charged the V88 power bank and then discharged it (at about a 10W rate) while monitoring the outgoing power. I expected to get significantly less than the nominal 88 W-hr energy rating [my experience with batteries is that you NEVER get the rated power]. To my surprise I got 88.4 W-hr from the V88 before the last capacity indication bar started flashing. [I quit there--I didn't want to run the battery all the way down to undervoltage shutoff.]I like that the unit uses [I believe] pouch-cell lithium polymer batteries, which I understand are much less likely to short out, overheat, burn or explode than lithium ion cells, especially if a manufacturer tries to eke every last mA-hr out of a Li-ion 18650 cell rating.During the first week of September (and at about 40 deg N latitude) on a clear hot day, from about 8 am to 3:30 pm, I saw maybe 10W average, 14.3W max of power delivered with the array lying horizontal (i.e., not optimal orientation). By momentarily tilting the array toward the sun (by hand ... I need to build a structure to do this) I got a maximum of 14.5W. That's less than the 20W nominal rating, but [as with batteries] I realize that it's difficult or unusual to achieve actual "rated" performance with arrays. It's possible the V88 was limiting input power near the end of charging, and of course the sunlight would be more direct (more overhead) on June 21 than early in September [and also more direct if one were at the equator!]. So the array may be capable of more than the 14.5W I observed. At any rate, I am satisfied with the observed performance and delighted with the product quality.I do have a couple of items I'd put on a "wish-list" of product features, but they are fairly minor:1. The labels for the input/output connectors are low-contrast and printed on the back side of the device (opposite side from the LCD display). Once I accidentally connected input power to the output [they have identical connector types]. Fortunately, no harm done--the unit took this in stride. I've since made labels and put them on the front side.2. I'm spoiled by my cell phone which reports battery state-of-charge (SOC) in percent. I don't know how truly accurate that cell-phone SOC number is, but it's satisfying to get a "full precision" value at a glance. The 6 bars showing the SOC of the V88 power bank are certainly adequate for the job, but a numeric display would be even better. I did a crude test, discharging the V88 from full charge and watching where the bars jumped down. [SOC determine by reading accumulated W-hr on a USB meter and assuming 0% corresponded to 88 W-hr discharge.] The V88's bar-graph "meter" appears to be very nonlinear. Here's what I observed (very approximate):1 bar shows whenever SOC is greater than ~0%2 bars when >2%3 bars when >15%4 bars when >35%5 bars when >50%6 bars show whenever SOC >75%I labeled the front of my V88 with these numbers for future guidance, but all the more reason why a numerical readout for SOC would be easier and more satisfying.3. This isn't a problem, just something I didn't find (well) documented. As is documented, you can hold down the power button when on and set the V88 for "always on" mode [so it doesn't turn itself off when little or no power is drawn]. However, if you power cycle the unit, it will then default (or so it appears to me) back to "Auto Off" mode. You need to manually set "Always On" every time you power the V88 on. That's a perfectly acceptable behavior, I just didn't see that mentioned in Voltaic's paper or online documentation [maybe I missed it?]Bottom line, I'm delighted with this clearly rugged hardware, and if I had any reservations about whether it would be worth the extra cost, I have none now.

I'm giving it a 5 because even though I had trouble with the original v72 battery, their customer service is INCREDIBLE and also because the replacement battery they sent is AWESOME. I had an issue with the first battery, but the replacement battery works right up to their specifications. I can finally be off the grid and still use my energy-sucking, 16.5v MacBook Pro!! Love this product! When it first arrived, I felt like the battery might not be working up to their specifications. When I contacted customer service, they were really good about responding to my concerns - I mean REALLY GOOD! We went through a list of possibilities, and they were patient with me while I tested the v72 battery on the solar panel and on the wall. In the end, they sent me a new battery, which performs like a rockstar - it turned out that the original battery wasn't quite up to standard. I am so appreciative of their help and their patience. I love the solar panel - no problems with it whatsoever. And, now I love the v72 battery as well!Now, on to the technical part...The battery does have an issue with its LED, which they explained to me after I questioned the capacity of the v72. They are working hard to resolve the issue and said they will have a new battery out in a few months that should alleviate the problem. But, if you buy one before then, just be aware...the LED blinking lights don't necessarily match up to the charge in the battery. Simply put, if the LED flashes 4 lights after being on the wall or solar panel for only an hour, don't believe that you have four bars! The battery isn't defective, the LED simply does not function correctly. I think you can solve the problem by just leaving the battery on the wall charger for at least 4 hours or on the panel for at least 6 hours of full sun. If that's not possible, then maybe just roughly estimate the amount of charge based on the amount of time you were able to have it on charge. The other thing to be aware of is that you may sometimes need to "reset" the battery if it turns itself off for any reason - say it gets too warm or you plug a 16.5v device in with the 12v option chosen on the battery. You just have to plug it into the wall outlet or the solar panel to "reset" it. But, that's in the instrutcion manual.I love the solar panel - it folds up nice and small, and the material feels sturdy. I haven't had many opportunities to test it's charging power, but the few times I have used it, even with cloud cover, it seems to charge very efficiently.The kit comes with loads of different adapters (which I haven't bothered to investigate since I am only using mine with my MacBook Pro) which is great if you have multiple devices that you are using the v72 for.The v72 battery has a sleek and shiny outer cover, which I really like. It seems very sturdy.Overall, I think voltaic makes great products. I'm a huge fan of Anker, and I think Voltaic is right up there with them. Form and function. It's nice to have well-made products that work and are aesthetically pleasing!

I bought this for my girlfriend's Dell Inspirion 5570. The battery for this laptop is rated at 18 Ah, the Voltaic battery is 24 Ah. The laptop reached 31% after 1/2 hour, 58% after an hour, 84% at 1.5 hours, 95% at 2 hours and 98% at 2.5 hours. The laptop was then fully discharged and plugged back into the Voltaic. This time the laptop was charge to 53%.... which is better than expected given the size of the two batteries. At this point the Voltaic display shows 2 bars out of 6 and still has plenty left to charge cell phones.The Voltaic website is pretty decent, but I think the Amazon site should make it very clear that Dell computers check to see if the charger is a Dell unit. It needs an adapter with a microchip that tells the laptop that this charger is safe, otherwise the laptop will not allow any charging to take place. There are two common adapter sizes used by Dell. Voltaic includes the larger one...which happens to fit my high end Dell Precision work station laptop. But it does not include the smaller adapter which fits the lower power/more common Dells. The adapter is $8 plus $15 for 3 day shipping from the Volaic website. I assume they could set up the Amazon site to suggest people buy this adapter, or better yet, simply include it with the battery. Customer service was very responsive, and I appreciated that.