We have had a number of requests to review ways to make electricity without the need for the grid, particularly for things like cellphones and tablet computers. I’ve been looking into options, and they usually boil down to solar, though I hope to get some products that use other strategies.
There is a huge range of solar solutions out there, from systems that can power a whole house to something that can keep a small battery charged. The whole house solutions can easily hit $40,000 or more when you include the battery backups, while the least expensive small ones can be as little as $10. Faced with this range, we have to decide what we need to do and how much we can afford.
A major problem hits those of us who prefer not to buy Chinese products. Many, if not most, solar products, particularly the small ones, come from mainland China. The one I’m writing about here is Chinese. This is, alas, simply a case of not being able to find alternatives.
Another difficulty is that many of the small solar panels just don’t produce enough power to do much. You will wind up needing to charge things more hours than you can use them.
Watts are the basic unit of measurement for the power produced, and I was very disappointed with a 5-watt folding panel I tried before this one. It was very hard to keep our Kindle Fire tablet fully charged, if we used the tablet more than a couple of hours a day. It also meant that the tablet had to be tethered to the panel all day, which worked best if outside. I also tried the charger that came with the panel for AA and AAA batteries, and I found it took most of the day to charge a set of four and they often still didn’t hit 100% charged. In theory, it was supposed to be able to charge both a USB device and the AA/AAA charger, but it just didn’t have the panache to pull it off. While the strategy was to use their AA/AAA charger to charge cells during the day and then use them to charge other devices later, it just wasn’t enough power to serve our needs.
I figured that I needed to look for more juice, and so I began scrolling around on Amazon. The Anker 14W Foldable Dual-Port Solar Charger turned up for $60, which was only a little more money than the 5-watt unit I purchased a bit over a year ago. Luckily, the price on solar panels is going down.
The Anker had good reviews on Amazon, and there were enough of them to make me feel they meant something. There are several comparable units on Amazon, and while they have similar rating and cost a little less, this one had the most ratings. So, I felt it might be the safest choice.
The Anker only includes a USB charging cable. Unlike the 5-watt unit, it didn’t have a 12-volt output, which I would have really liked. It did, however, have two USB ports rather than the one on the smaller panel. USB will charge most tablets and current cellphones. Additionally, there are a number of USB chargers for AA and AAA batteries, though I haven’t found any that offer rapid charging. While it is better to slow charge batteries, it is nice to have the option to go faster in a jam. A 12-volt output would have provided the option to charge a car battery, a number of other devices, and more sizes of batteries. I haven’t, for example, found a way to charge C or D batteries with USB. I’m sure there are those who could make that happen, but I haven’t located an off the shelf solution for the non-technicians among us.
I picked folding units, because I wanted something that could be easily carried, stored, and deployed most anyplace. You often see these hung on backpacks and used while hiking. It has grommets on each end to allow it to be tied down. This particular unit folds to 11×6.9 or a bit smaller than a sheet of printer paper. It is 1.5 inches thick when folded. It unfolds to 34.6x11x.5 inches, and it weighs 27.9 ounces.
Because solar panels are most efficient when aimed directly at the sun, I discovered that I could lay it on the backrest of a reclining lawn chair and use a clamp to hold it in place. I then moved the chair to keep it aligned with the sun and avoid the shadows that move across my yard as the day goes by. By tilting the backrest up and down, I could better aim it in the early morning and then reposition it for midday.
Anker rates this at 2 amps at 5 volts, but that only gets us to 10 watts. I assume that the missing watts are used up somehow in the charging system. Anker says they use PowerIQ Technology, which allows the charger to adapt to almost any USB device, and that is a very good thing. I’ve had a number of devices that would only charge from the manufacturer’s charger, which was highly irritating. So far, everything I’ve tried has worked with this one.
The USB plugs are located in a pocket that folds up on the inside when you store the charger. It can also hold some USB cords to connect your devices. They provide one that will connect to a micro USB plug; however, since there were two outlets, I added a second one. I was thinking that it might be smart to include a mini USB cable, as there are still a few items that use that style plug. Micro USB was designed for many connect/disconnect cycles as one would use with a charger while the mini size was really intended to just be connected and left alone.
I no longer have any nickel cadmium batteries, so all of the testing with AA and AAA cells was done with nickel-metal hydride cells (NMH). The AA cells ranged from 1,900 milliamp hours (mAh) to 2,300 mAh, while the AAA cells were 750 mAh. I primarily used our Kindle Fire to test charging of USB devices, but I also plugged in an iPod and a couple of cell phones to see if they would charge. All did.
The AA and AAA batteries were charged in a little unit that came with a Solaraid 5-watt panel I bought earlier. If you have charged batteries in it, you can plug a USB device into it and charge the device. This kit is no longer available as far as I can determine, and I was disappointed with it. The terminals for the batteries tend to collapse and have to frequently be bent out or you don’t get contact. At some point, there is going to be fatigue and the contacts will break. I also felt the 5-watt panel wasn’t adequate to do much charging. It was a bit of a struggle to keep 4 AA’s charged every day, and it just didn’t seem able to get the Kindle fully charged.
You can also plug the little charger into a USB port on a computer or other USB charger, and it works pretty well, charging four AA batteries in about five or six hours and AAA batteries in three hours or so. I am going to find a similar product to replace it, since I expect the contacts to pack it in sooner or later.
The Kindle Fire has a 4,400 mAh 3.7-volt battery, which should charge in about three hours on this unit. Initially, it took between five and six hours on the Anker solar charger, but that improved to about three hours. I’m not sure why, unless some clouds came by while I was inside. The 9-watt Amazon wall charger will do it in three hours.
I measured the output on the panel with a $14.00 PortaPow USB Power Monitor while charging the Kindle Fire and the AA battery charger. The Kindle alone drew about 8 watts, and when I added the AA charger to the second outlet, it dropped to about 3 watts. The AA charger was drawing about 3 watts as well. I had expected, of course, for the power to be split, but had hoped the total would be higher.
As with all solar devices, you need a lot of sunlight to make them work well. The Anker charger has an LED that indicates it is making power, which is very welcome. As with any solar panel, it works best when aimed perpendicular to the sun. You have to keep it moving during the day, if you want to get the most out of it. It did produce current when the sun went behind clouds, but the Kindle Fire would usually stop charging. The AA/AAA charger, however, kept blinking its LED’s, indicating that it was continuing to charge.
I have an assortment of rechargeable AA and AAA batteries on hand, but I have started to standardize on the Eneloop brand. They are NMH cells with 2,100 mAh for the AA’s. They offer the huge advantage of being low self-discharge (LSD). Earlier NMH batteries would usually completely discharge if they sat on the shelf for a month or two, which is a terrible shortcoming. Eneloops can hold most of their charge for years. The latest version can be recharged as many as 2,100 times– another critical advantage if one anticipates disruptions in the supply chain. Unfortunately, Eneloops only come in AA and AAA sizes, but they offer holders so you can use them to replace C or D cells. They have less power, of course, than a C or D, but they will work. Several other companies are offering this technology, and I have used the Tenergy 9-volt batteries with success, though I haven’t found a USB charger for them. Tenergy also offers LSD C and D cells, but their products come from China. The Eneloops are Japanese.
The question, of course, is how much you can do with a few AA cells and a tablet, should that be all the power you have. You will have to judge that for yourself, but I have found I can keep an Energizer LED lantern going all night without problems and get at least two to three hours of runtime on the Kindle Fire using the Anker 14W unit. I had to use the holders that upsize the AA’s to D cell size for the lantern, but I was very surprised at how long it ran with the smaller batteries. For my family, having just these two items usable would be a big help. A lot of reference material can be stored on the Kindle that might be invaluable in a crunch. We also have an assortment of radios for AM/FM and shortwave, along with a bunch of two-way radios that can run off of AA batteries.
The biggest drawback is managing the batteries and chargers. The panel needs to be aimed several times a day, and you must remember to put things on the charger. A series of rainy days will cause problems, unless you have enough panels to stay ahead on the charging chores. You also have to be mindful that they are sitting outside and need to be in a secure area lest someone make off with them.
Solar power is, in most respects, the perfect power source for preppers or anyone who craves independence. It is clean and requires little work, other than planning. There is no fuel to store and it makes no noise. The problem is getting enough power. I feel like the bad guy character in the movie Key Largo who just wants “more”. The Anker 14W is going to help our preps and also serve well on camping trips, but we are going to need more power to keep our key systems working. A number of them require 12 volts, so this quest for power is going to be a continuing saga with more reviews to come.
I am still getting good use from the Work Sharp I reviewed last September, but I did discover one drawback if you aren’t careful using it. You can round off the tip on your knife. I got in a bit of a hurry and somewhat careless when sharpening some of our kitchen knives, and I began to notice that they no longer had well-pointed tips. I did some research and found that I’m not the only one who has done this. It isn’t terribly hard to avoid, but you must be careful when you pull the knife across the belt as you near the end of the blade. It is pretty easy to continue with a twisting motion, but that will rotate the tip across the spinning belt, which causes the problem. Take some time at the end of the stroke and watch how the tip proceeds through the machine, and you should be fine. I still like the tool, but I wish I weren’t faced with going back and fixing my wife’s knives. Hopefully, if you bought one, my experience will save you some trouble.
– SurvivalBlog Field Gear Editor, Scot Frank Erie