Using a solar charger is one of the best ways campers, hikers, climbers etc. can charge their smartphone, GPS, tablet and other mobile electronics when off the grid. This article will help you understand what they are and how to find the right one for you.
Solar charging panels are typically rated in Watts, and how many of those you will need depends on the type and number of devices you want to charge. If you all you need to charge is a cell phone or mp3 player, a 5 Watt panel should work alright. On the other hand many today's smartphones, with large screens and fast processors are likely to need a larger 7-10 Watt panel to satisfy their energy needs.
If you have a even larger devices, such as iPad, or want to charge two smartphones, you will be looking at even larger solar charging panels, at least 15-20W.
It is important to know where and when you will use your solar charger, or more accurately - how many hours of sunshine a day can you realistically expect. The Watt numbers above assume a good summer weather, with a good amount of sunshine. If you plan to charge your electronics in darker months, when days are shorter and cloudier, you will always be better off investing in larger and more efficient panels. They will pull some decent Watts in cloudy weather, and can charge your devices faster whenever the sun does get through.
When picking a solar charger you should pay special attention to how many USB ports the charger has, and how many Amps of current you can get out of them. Amps mean how fast you can charge your device, for example a 1 Amp port will charge your smartphone faster than a 0.5 Amp port. Some chargers offer maximum Amp output of 2.1 Amps, however it is split into two or more USB ports. If you connect all of them at the same time, they will be charged at a slower rate.
There are basically three different types of solar charger panels:
Solar chargers with monocrystalline panels seem to be the best choice for personal use, because they combine durability with high efficiency.
Some solar charging panels come with a battery, which can be slowly charged by the solar panel during the day, and can be later used for recharging your devices after sunset. The battery can be separate, or built-in. Many smaller charging devices are in fact small power banks with a similarly small solar panel. Unfortunately due to the panel size, they are unable to charge any decently-sized battery in a reasonable amount of time.
If you plan to use your portable solar panels for camping or hiking, small dimensions are essential. If weight is the most important, you could take another look at CIGS thin film panels, as they are the real light weight there. Look for the most rugged and durable you can find.
On the other hand, if portability is what you're looking for, and you're not going to be off-grid for very long, you might come to the conclusion that an external battery or a power bank might be better in your situation. You will be able to charge your phone at least a few times and you won't have to worry about the weather. When it comes to the size and convenience, it would perhaps then be your best choice.
One of the best ways to figure out value of a solar panel is to divide the price of the solar panel by the number of Watts it can produce. If they panel you're looking for costs $60 and is rated at 5 Watts, that means $12 per Watt. The less you pay per Watt, the more the panel is worth, although you should also look at features and accessories the panel comes with to make a good judgment.
In the list below you will find the solar chargers you might be interested in looking at in your research:
This solar charger from EnerPlex delivers 6 Watts true output, which means that with direct sunlight it can charger your USB electronics at the similar rates as your wall socket. The charger is flexible and very light which makes it perfect for campers and hikers. At the same time it was designed for harsh outdoor conditions, which means you don't have to be afraid to drop it or spill water on it. EnerPlex Kickr weighs just around 0.6 pounds (296g) and its unfolded dimensions are: 775 x 185 x 2mm.
This all-in-one solar charging kit from Goal Zero includes a 3000mAh/11Wh lithium ion battery, Nomad 7 solar panel, Switch 110 Lumens flashlight and a small fan for personal cooling. The battery can be quickly charged witha a 1.5A USB port. If you're outdoor, you can use the included solar panel to recharge the battery. It should take around 4 hours in full sun conditions. The Switch 110 flashlight has adjustable light power, so that you can save energy when using it over extended periods. This is a great product if you're off-grid, but want to be able to use your portable electronics.
Renogy Firefly provides up to 175Wh of energy and can charge USB as well as AC appliances on the go. (up to 150W) This solar suitcase includes two high-efficiency solar panels rated at 10W for a total output of 20W, 10Amp solar charge controller, 150 power inverter and one 16 Amp Hours lithium polymer battery. The case is made from a durable and waterproof material, made to work in all-weather conditions. It has been designed for off-grid use and emergencies.
Goal Zero Nomad 7 was designed to charge your USB and 12V devices on the go. (it might be not enough to charge your tablet) The solar panel is made of highly efficient monocrystalline cells and is rated at 7 Watts. A LED indicator show the strength of solar charging, so that you can adjust the panel angle for maximum charging performance. It is built with durable and waterproof materials to withstand the demands of outdoor use. The weight of this unit is just 9.2 oz (260g) without a kickstand and the folded dimensions are the following: 6.5 x 8.75 x 0.75 inches. (16.5 x 22.2 x 1.9 cm) It has a 1-year warranty.