For a long time I was against the idea of buying a solar powered charger for camping. But then I saw a venomous viper 1 yard from my tent while wild camping with my 6 year old. I realized how much it would suck if my phone was dead and was unable to call the local police or rangers if she got bit.
So, as much as I am personally opposed to using your phone while in the outdoors (or any other device – seriously, you should be enjoying a good digital detox and not checking your email!), it is still good to have a portable solar charger to keep your phone juiced in case of emergencies. Likewise, anyone dependent on GPS for navigation will want a reliable way to keep it powered. And I’m sure there are a zillion other good reasons to have a solar charger while outdoors.
- Best Solar Chargers Reviewed
- Types of Portable Solar Chargers
- How to Choose a Portable Solar Charger
Top Picks Overview
#1: Suntactics S5 (5 watts; 7oz – $$$)
This isn’t the lightest solar panel you’ll find, but it’s damn near close. It also has nice features like auto reset and a high waterproof rating. It also doesn’t have an integrated battery, so you’ll have to use it with a power bank (like one of these ultralight power banks).
#2: ECEEN Solar Charger (13 watts, 9.3oz – $)
The portable solar panel by ECEEN is designed for outdoor use. It delivers 13 watts in just 9.3oz, and can charge two devices at once. It has features like auto-reset, waterproof, and straps for attaching to your backpack. The only reason it doesn’t get the #1 spot is because it hasn’t been field-tested as doesn’t seem to be as reliable as the Suntactics S5 solar panel.
#3: BioLite SolarPanel 5+ (5 watts; 13.8oz – $$)
This solar panel has a built-in battery, so you don’t need to bring along a power bank. The only major downside is that it doesn’t have an auto-reset feature, so isn’t great for cloudy weather.
Best Solar Chargers Reviewed
When choosing a portable solar panel, you’ll mainly want to look at the amount of power supplied (watts), the weight, and how this balances with cost.
If there is no integrated battery, you’ll have to use the solar panel with a power bank. This will add another 5-10 ounces or so (read my upcoming post on best ultralight power banks).
Make sure you choose a reputable brand. The cheap knockoff brands can’t be trusted to give accurate info. It’s worth it to pay an extra $10-$20 to ensure you get the advertised wattage.
Tip: Don’t forget how important cables are! Choose quality cables so you can charge faster and have less power loss.
Anker PowerPort Solar Lite 15w (Currently unavailable)
In pretty much every list of the top portable solar chargers, the Anker PowerPort Solar Lite takes the #1 spot. There is good reason for this. The solar charger is very reliable, doesn’t have issues with bouncing back to full charge after shadows pass overhead (auto reset feature), is pretty lightweight, durable, and a good value. It also comes in a 21w version if you need more power.
Some other perks of the Anker PowerPort solar charger is that it has elastic loops for attaching it to your pack and a pocket for holding your devices.
Note that this solar charger does not have an integrated battery. We recommend pairing it with the ultralight Anker Astro power bank (4.2oz) so you can store power. The total setup weighs in at 16.7oz.
- Watts: 15
- Weight: 12.5oz
- Size: 11×6.3” folded, 18.1×11” open
- Auto reset: Yes
- Integrated Battery: No
- Connections: 2
- Cost: $$
Best For: Changing devices quickly while camping, backpacking, or hiking
The Solar Paper by Yolk Station is marketed as the “world’s thinnest and lightest solar charger.” At just 0.4 inches thick, it really does live up to its promises.
In addition to being super small, the Solar Paper have some other great features like a 23.7% efficiency, auto reset (which is important for when those annoying shadows pass over and cause charge speed to reduce!), an LCD amp meter which shows charging speed, and waterproofness to IP64 rating. One panel is 5 watts, but additional panels can be easily added with a magnet system.
The only downsides of this portable solar charger is that it is fairly pricy, doesn’t have an auto-reset feature, and its bare design doesn’t have any straps. One panel will be enough to charge your phone. To charge tablets, you’ll need at least 2 panels.
- Watts: 5w (additional panels can be added)
- Amps: 1
- Weight: 4.8oz
- Size: 3.5×7.5”folded, 7×7.5” open
- Auto reset: No
- Integrated Battery: No
- Connections: 2
- Cost: $$$- Buy Here At Best Price
Best For: Lightweight backpacking
This brand is best known for making ultralight solar panels for backpacking. It is only 7 ounces, which makes it one of the lightest per wattage available. Pair it with the Astro battery bank for a setup which weighs just 11.4 ounces total. The Suntactics also has smart features like auto reset, a high waterproof rating, and durable design. It’s a bit pricy but worth it if you are trying to cut down weight.
- Watts: 5w
- Amps: 1
- Weight: 7oz
- Size: 6×6”folded, 6×11” open
- Auto reset: Yes
- Integrated Battery: No
- Connections: 2
- Cost: $$S – Buy here at best price
The ECEEN is really well designed for outdoor use. It has pockets where you can keep your gadgets while charging, a built-in stand, straps, and is waterproof. The most standout feature of this solar charger though is that it is lightweight at just 9.3 ounces
The only major downside is that you aren’t going to be able to charge two devices at once quickly. The 2amps is for ideal conditions. Connecting two devices to the solar charge will have a maximum of 1amp per connection, but realistically it’s going to be a lot less.
- Watts: 13
- Amps: 2
- Weight: 9.3oz
- Size: 7×12.7” folded, 14×12.7” open
- Auto Reset: Yes
- Integrated Battery: No
- Connections: 2
- Cost: $ – Buy Here At Best Price
Best For: People who want a cheap solar charger that won’t weigh them down.
This is one of the most popular solar charger for backpacking. It is a kit which consists of folding solar panels and a lightweight battery pack.
The way that the kit is set up means that you can charge devices directly from the Nomad 7 solar panels. Or you can charge the Goal Zero power bank and use that to charge your devices later. Oh, and it’s possible to charge 2 devices at once!
It has a reliable auto-reset feature, so it won’t stop charging if a cloud passes overhead. Another major plus is that it’s waterproof rated to IPX6, which means you can fall in a stream and it will still work. 🙂
The main issue with the Goal Zero kit is that it isn’t very lightweight (21.8 oz.). It’s also fairly pricy. Still, a lot of backpackers love this kit because it is so reliable. I would go with the more powerful, lighter the Anker PowerPort Solar Lite.
- Watts: 7w
- Amps: 1/2.4
- Weight: 8.8oz (battery pack) + 12.8oz (solar panel) = 21.6oz
- Size: 6.5×8.75×0.0.75” (solar panel folded); 4.5×3.25×1” (battery pack)
- Auto Reset: Yes
- Integrated Battery: Yes – 7800 mAh
- Connections: 2
- Cost: $$S – Buy here
The company BioLite makes some really cool alternative-energy gear. Their solar panel is no exception. It is very small and pretty lightweight (considering that the battery pack is integrated). The little kickstand allows you to position the solar panel towards the sun easily.
Yes, it does take a while to charge with this tiny solar panel. However, it has good reviews overall and does its job well. You’ll be able to clip the solar panel to your pack during the day and then use the battery to charge your phone/device at night.
- Watts: 5w (10 watt model also available)
- Amps: 1
- Weight: 13.8oz
- Size: 10.1 x 8.2 x 1.0 inches
- Auto Reset: No
- Integrated Battery: Yes – 2200 mAh
- Connections: 1
- Cost: $$- Buy here
This solar power bank has a huge capacity of 25000. That’s 10x more than most portable solar chargers. It will charge an iPhone 7 nearly nine times. Of course, that does mean it will take about 10x longer to fully charge the battery pack. At a conversion rate of 200mAh per hour, you’ll need 12 hours of sunlight to fully charge the battery pack.
It also has a built-in flashlight. This feature is really unnecessary for backpacking, but is nice if you want something for emergency preparedness.
The downside of such a huge capacity power bank is that it is heavy! It is definitely not suitable for thru-hiking, but would be great as a backup power source for multi-day backpacking trips – especially if you use your phone often.
*There’s also the BLAVOR solar charger. It only has 10,000mAh capacity, but is lighter weight at 8.5oz.
- Amps: 2.1
- Weight: 15.5oz
- Size: 7.5 x 3.9 x 1 inches
- Connections: 2
- Cost: $ – Buy here
The SLXTREME is currently the best solar cell phone case for backpacking. It has a waterproof rating of IP68, so you can literally let your phone fall in water and it will be ok. It also makes your phone drop-proof and dust-proof. Perfect for outdoorsy people!
As far as charging your phone goes, it will be slower than if you used a standard power outlet. However, it only takes about 1 hour of charging to give you 10 more minutes of talk time. There’s an area on the outside of the case where you can attach a carabiner to keep your phone on your pack while hiking.
There are different models for the iPhone 5, 6, and 7. Note that the Amazon description gives some inaccurate info about the battery and weight compared to the user’s guide.
- Amps: 1.4
- Weight: 7.5oz (without phone inside)
- Size: 6.56×3.35×1”
- Integrated Battery: Yes – 4000 mAh
- Connections: 1 (for charging phone only)
- Cost: $$- Buy Here At Best Price
Types of Portable Solar Chargers
If you don’t know much about portable solar chargers, read this before you buy. Otherwise, you might find yourself with an impractical solar panel.
The main thing to consider is whether the solar panel has a battery or not. If not, you’ll probably need to pair the panel with a lightweight power bank for storing energy. Read on to learn more about choosing solar panels.
Option 1: Portable Solar Panels without Battery
These are just solar panels without a battery. You simply plug your device into the solar panel, put it in the sun, and let it charge.
The main issue with these is that you have no way of storing power. So, if you need to charge your device and it’s a cloudy day, you are screwed. One solution is to bring your own power bank. Just use the solar panels to charge the power bank, and then charge your devices from the power bank. This gives you a lot of versatility because you can choose the solar panel and power bank size that suits your needs.
Most power banks are really heavy, but there are some lightweight options. The Anker Astro battery pack, for example, is lightweight at 4.2oz and could charge an iPhone 6 nearly two times.
Another issue with these solar panels is that if sunlight reduces during charging, the power output reduces – and stays at that reduced rate. That means a shadow passing over the charger can reduce output to practically zero!!
The problem is easy to fix: you just unplug the phone and plug it back in. Charging will resume at full capability then. However, it’s incredibly annoying to do this. It’s also incredibly annoying to come back to base camp after a long hike only to realize your phone hasn’t charged at all because a friggin’ cloud passed over after you left!
Many solar panels have an “auto reset” feature which ensures the panel continues to charge at full strength, even after clouds pass over. Be careful when choosing a solar panel as not all have this feature. Even popular models like the Poweradd 14 and Instapark Mercury 10 will stop charging when shadows pass over. It’s important to look for a solar panel which has “auto reset” feature By contrast, solar chargers like the Anker PowerPort Solar Lite will return to full charge once the shadow passes.
Another thing to watch out for: You may not be able to directly charge your devices with the panel. Check the compatibility, or you may need to get a charge controller to use with the panel.
- Lightweight: Without a battery, these are the lightest option.
- More surface area: These solar chargers fold out to capture the most sun.
- Fast charge: Because of their large surface area, these are generally the fastest at charging devices.
- Directly charge device: There is no need to first charge an integrated battery and then charge the device.
- No way to store power: Without an integrated battery, there is no way to store extra power for later use. You could bring your own power bank to charge, but this means extra weight.
- Shadows can screw up charging rate: An annoying fluke with solar chargers is that, if sunlight reduces while charging (such as a cloud passing overhead), the charging output will reduce and stay at that rate. To get the rate back up, you’ll have to unplug and replug the charger. Obviously, you can’t do that if you left your solar charger out while you went for a hike. Some models, like the Anker PowerPort Lite don’t have this fluke.
- May need a charge controller
Choose this option if: You are bringing your own power bank or don’t use your devices often, so are okay topping them up whenever there’s good sunlight.
Option 2: Solar Panels with Integrated Battery Packs
These solar chargers have a battery in them. First you charge the battery, and then you charge your device with it. Having a battery means you can store excess power, which is a lot more reliable. It also means you don’t have to worry about compatibility issues or charge controllers. The battery is usually compatible with all devices.
The main issue with them is that they are usually a lot slower on both ends. They are slow to charge the integrated battery, and then the battery is slow to charge your device. You also have to be careful that the battery capacity (measured in mAh) meets your needs. It can be hard to find a solar panel with the exact specs and battery size you need.
- Usually no issues with passing shadows causing it to stop charging
- Store the power for later charging
- Can charge battery at home/in town
- Integrated battery means extra weight
- Usually much slower than direct charging
- Integrated battery often has low capacity
- Often poor-quality, inefficient battery
Choose this option if: You use your devices often and need the reliability that comes with a built-in battery.
Option 3: Solar Power Banks
A lot of times, you might not even need a solar charger for your trip. A power bank could provide enough backup juice for recharging your devices. For example, on a 3-day trip where you are using your phone to take photos, a 7,000mAh power bank would recharge your phone completely 2-3 times.
Solar power banks have a solar panel built into them. You can use a standard wall outlet to charge the solar panel, or you can use the solar panel. The issue is that the solar panel on these is tiny, so it will take forever to recharge the power bank. For example, one good power bank takes 56 hours to completely recharge with its solar panel! That’s not reliable if you need to recharge often, but is good if you only need it for emergency backup.
- Easy to use
- Lightweight solution
- Tiny panel means it takes forever to recharge
Option 4: Solar Cell Phone Cases
These are a completely different type of portable solar charger. They go over your phone. Need to charge your phone? Just set the solar panel side in the sun and it will start charging.
The downside is that you won’t be able to use it to recharge other devices. However, they are lightweight (especially since you are probably carrying a case on your phone anyway). Most are made for outdoor use and have features like making your phone indestructible and waterproof.
- Protects your phone
- Quickly charges
- Can’t charge other devices
- Will have to keep your phone outside or clipped to your pack when charging
Best for: Clumsy people, everyday use, or if you only want to charge your phone
Choosing a Portable Solar Charger for Outdoor Use
There are so many solar chargers out there now. Here, I’m going to focus on what you need to look at for outdoor use.
I’m also going to focus on solar chargers which are actually portable. That immediately eliminates a lot of “camping” solar chargers because they are designed for RVs and car camping. Some of those camping solar chargers are meant to power friggin’ TVs and weigh a ton!
Portable Solar Charger vs. Power Bank
Solar power is awesome, but a solar panel is unnecessary on most short trips. Portable power banks can hold up to 25,000mAh without getting too heavy, which is plenty of power to keep gadgets like phones, camera batteries, headlamps, and GPS trackers charged.
However, power banks are a pain in the ass on longer trips where you will need to recharge frequently. As several thru-hikers mentioned about their experiences using a power bank, they had to recharge it when making rest/fueling stops in town. Since power banks take forever to recharge, you end up losing a lot of time. It forced them to stay in hotels to have a way to charge the damn thing, so ended up costing a lot of money too.
It really depends on how you are using your devices while hiking, camping, and backpacking though. Since solar powered phone chargers are getting so cheap, it might be worth it to have the reassurance of a more reliable power source than what battery packs offer.
- Day hikes: you probably don’t need any portable charger.
- Trips up to 3 days: You might need around 3,000 to 20,000mAh, depending on how often you are using devices.
- Photography trips: If you are staying in one spot, then a solar panel makes sense because you can capture maximum sunlight.
- Thru hiking: Calculate how long you will go before refueling. If you are refueling weekly, you can recharge the power bank in town – though it’s a pain in the ass to wait around for it to charge. A portable solar panel might make sense if you don’t want to recharge in town.
Watts: You are going to need at least 10 watts for charging a phone or GPS. More watts is better, but will add weight and size to the panel.
Amps: 1 amp is okay for older phones. But you should really get at least 2 amps – especially if you plan on getting a newer phone and don’t want to wait all day for the phone to charge. 2 amps will also charge tablets and even laptops at a reasonable speed.
Once you start looking for solar chargers, you’ll realize that the definition of “portable” varies a lot. Some manufacturers label their solar chargers as portable even when they weigh over 5lbs. Backpackers wouldn’t find these too portable!
Unfortunately, most solar chargers are still nowhere near the weight requirements of ultra-light backpackers. Extra to carry around at least an extra 12-20 ounces. You can find lightweight solar chargers (like some of the ones listed above), but they do charge much slower than the bigger, heavier chargers.
- Solar chargers that can connect to your backpack. This is great for charging as you hike (especially with integrated battery chargers)
- Panels that can be easily propped up. It will help you get maximum sunlight.
- Flexible or rigid panels. Flexible panels are less likely to get broken and a bit easier to use. Rigid panels should be foldable so you can pack them easily.
- Waterproof: By their nature, solar panels are waterproof. What you want to look at is how waterproof the solar charger connections and batteries are.
- Panel type: As a general rule, monocrystalline solar panels are the most durable and rugged. However, they are also the heaviest and thickest. CIGS panels (thin film) are next, followed by Polycrystalline
Good brands of portable solar chargers will list their efficiency rating. Anything above 22% is a fairly good efficiency.
Aside from the manufacturer’s listing, you can also determine solar charge efficiency by looking at:
- Panel type: Monocrystalline solar panels are the most efficient followed by polycrystalline and CIGS.
- Panel surface area: The larger the solar panel, the great its surface area and the better it will be able to convert solar energy into power. You’ll really see the difference in efficiency when the sunlight is less than ideal, such as on cloudy days.
Number of Connects and their Amperage
If you just need one connection for your solar charger, then choosing one is easy. Things get complicated when you need more than one connection port.
The reason is because most portable solar chargers list their TOTAL amperage for ALL connections. Let’s say you want to charge 2 power-thirsty devices on a 1amp solar charger. The solar charger splits the amps between the connections, so they both charge slowly.
Some devices won’t even start charging unless they can get a certain amperage level, so having multiple connections could backfire on you!
By contrast, some solar chargers list the amperage of EACH connection. Or, some solar chargers even have connections which have higher amps than others so you can put your priority device to charge there and leave the other device for the slower connection.
To figure out the value, look at the price per watt of the solar charger.
Total price divided by watts = price per watt.
Portable solar chargers are getting cheaper all of the time. It used to be that $10 per watt was a good deal. Now you can find quality portable solar chargers that cost less than $3 per watt.
Understanding Volts, Amps, mAh, and Watts
Let me preface this by saying I am NOT a tech person. However, after some reading, even I was able to get the gist of volts, amps, and watts. You need to have a general understanding of these electricity terms if you want to buy (the right) solar charger for your devices.
Metaphor for Understanding Electricity Terms
The standard metaphor used to explain the terms below is water going through a pipe.
- Watts = total water
- Volts = water pressure
- Amps = size of pipe
If you have high water pressure (volts) and big pipes (amps), then you are going to have a lot of water (watts) going through the pipes.
This is energy potential of the charger. All USB cables run at 5 volts (thus anything that charges via USB takes 5 volts). If you were to try charging your cell phone on a 12 volt solar charger, it wouldn’t be able to handle that much electricity. You’d see sparks and melting plastic! Luckily, we don’t have to worry about this happening because solar chargers designed for USB devices are standardized at 5 volt.
On the flip side, don’t try charging your phone on a solar charger with higher voltage! You’d need an adapter to do this safely.
The amount of electricity that can flow at once is measured in amps.
- Older cell phones will handle about 1 amp.
- Newer fast-charge phones will handle upwards of 2 amps.
- Devices which use more power (such as tablets) usually handle around 2 to 2.5 amps
You want high amps so your phone can charge faster.
But, if your device has low amp potential, then getting a high-amp charger isn’t going to help it charger faster. Your phone can only charge as fast as its amp rating.
For example, as Techlicious explains, the iPhone 6 supports 1.6 amps and comes with a 1 amp charger. You could use a 2.2 amp charger with it – but it will still only charger at a maximum of 1.6 amps.
Milliamp Hours (mAh)
Phone batteries are often measured in milliamp hours (mAh). Or, sometimes they are listed in amp hours (Ah).
1 Ah = 1000 mAh.
This is a measurement of the battery’s capacity. A lot of people use it to gauge how long a battery will last. The ZenFone 3 Zoom has an impressive 5,000 mAh battery. The LG X has a 4,500 mAh. Most newer phone batteries are going to have around a 3,000 mAh capacity though.
Once you know the mAh rating of your battery, you can figure out how long it will take to completely charge. For example, if your solar charger is capable of giving out 1 amp of power, in one hour it will charge 1,000 mAh. A 3,000 mAh battery would take 3 hours to charge (assuming ideal conditions – which pretty much never happen).
Volts x amps = watts
Since we know that all USB solar chargers are 5volt and most devices aren’t going to draw more than 2 amps at once, we can figure out how much watts we need our solar charger to have.
5 volt x 2 amps = 10 watts.
In the perfect world, a solar charger would always give out its maximum volts and amps. We know this isn’t true though. That’s why it’s good to look for solar phone chargers with higher wattage. 10 watts is the minimum you should look for in a solar charger for your phone. 20 watts is better.
Do you have a solar charger for camping, hiking, and backpacking? Which one and how do you like it?
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