Best Portable Solar Chargers of 2024
Top Solar Panels for camping, basecamping, and outdoor adventures
Home > Gear Reviews > Electronics
May 30th, 2024
Updated to reflect updated technology and discontinued models and price changes
Electronics are a part of the adventurer’s quiver of tools more than ever before. Thanks to efficiency advances and cost decreases in solar cells, portable solar chargers are finally proving to be a viable means of providing electricity outdoors. A backcountry user might carry a smartphone, GoPros, headlamp, tablet, camera, headphones, and PLB or GPS devices. A family on an extended weekend trip will likely bring multiple smartphones, tablets, speakers, laptops, electric lanterns, and more. Rafters, climbers, bikepackers, and mountain bikers on a weekend mission might haul out even more high-powered lights and GoPros, radios, and other electronic equipment.
By harnessing the energy of the sun, anyone can charge their legion of devices rather than carrying physical batteries or draining the battery in their vehicle or camper. From portable solar chargers that can accommodate multiple devices during a family camping trip, to power banks that hold the biggest charge, to lightweight options for backcountry users that weigh under a pound, we reviewed top models to find the best portable solar chargers for most outdoor uses. Plus, we’ve got tips and tricks on how to get the most out of your portable solar panels, power banks and chargers.
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Portable Solar Chargers Comparison Table
| SOLAR CHARGER | TREELINE AWARD | MSRP* | WEIGHT | FOLDABLE | SOLAR CELL OUTPUT | POWER OUTPUT TO DEVICE | INTEGRATED BATTERY | PORTS |
|---|---|---|---|---|---|---|---|---|
| Big Blue 28W USB Solar Charger | Best Overall Solar Charger Read why |
$70 | 1 pound, 5 ounces | Yes | 28W | USB, 5V up to 2A (28W max) | No | 2, 2.4 Amp USB-A Ports |
| Goal Zero Nomad 50 | Best for Camping and Basecamping, Best Upgrade Solar Charger Read why |
$250 | 6 pounds | Yes | 50W | USB, 5V up to 2.4A (12W max)/8mm: 14-22V, up to 3.5A (50W Max) | Goal Zero Sherpa 100 AC sold separetely | 1 2.4 Amp USB-A Port, 1, 3.3 Amp Solar Port in 8mm 1, 3.3 Amp Solar Port out 8mm |
| BioLite SolarPanel 10+ | Best Solar Charger with Integrated Battery Read why |
$150 | 1 pound, 3.4 ounces | Yes | 10W | use integrated battery | Yes, Battery Storage Capacity (mAH): 3,200 milliamp hours | 1 Micro USB in, 1 2.4 Amp USB-A out |
| BioLite SolarPanel 5+ | $100 | 13.76 ounces | Yes | 5W | use integrated battery | Yes, Battery storage capacity 3200mAh Li-on, 8 Wh | 1 Micro USB in, 1 2.4 Amp USB-A out | |
| Goal Zero Nomad 10 | $99 | 1.2 pounds | Yes | 10W | 6-7V | Goal Zero Sherpa 15 AC sold separately | 1 2.4 Amp USB-A Port |
The Best Portable Solar Chargers
We had three clones to evaluate, all of which performed similarly well, so it was hard to determine which of those to award. However, one did surpass the others, as various sites have mentioned. We also considered different use cases in making our final judgments. As such, some of our winners are in unique categories.
Overall Winner: Big Blue 28W USB Solar Charger
Weight: 1 pound, 5 ounces
Solar Cell Output Capacity: 10 watts
Power Output to Device: USB, 5V up to 2A (28W max)
Foldable: Yes
Integrated battery: No
Ports: 2, 2.4 Amp USB-A Ports
What we liked: simple, lightweight, provides more power than similar models, can charge multiple small devices, includes ammeter
What we didn’t like:
Our overall winner is the 1 pound, 5 ounce Big Blue 28W USB Solar Charger for most outdoor use. It’s a simple, lightweight, and powerful solar power charger that seems to provide a little more power than its competition. It will also provide enough power in direct sunlight to charge multiple small devices for one or two people.
The Big Blue unit we tested also included an ammeter, which displays the amount of electrical current the solar panel is generating, setting it apart from the competition. That allowed us to see that the device was working and how much energy it was producing.
View the Big Blue Solar Charger
Charging the solar panel on the back of a backpack to provide energy for the headlamp on top.
Other than that, we found that it was remarkably, if not eerily, similar to two other top-rated solar chargers we evaluated. All three (the Anker 21 Watt PowerPort Solar charger, the Nekteck 28 Watt solar charger, and the BigBlue 28W USB Solar Charger) use the same basic design with two USB-ports and a light to indicate that they’re getting a charge; the Big Blue’s light indicator is the ammeter.
The solar cells in these foldable units are encased in PET polymer and surrounded by polyester canvas. Each offers moderate IPX4 water resistance — although you don’t really want to use these devices in the rain anyhow. They’re so similar they even use the same solar cells — SunPower’s Maxeon solar cells — which are among the most efficient commercially available solar cells and can convert up to 25 percent of the sun’s energy.
Each of these solar chargers had metal grommets in the casing, which allows you to attach them to a rock, backpack, tent, or camp chair. Each has a pouch where you can store the devices being charged and cords for charging your devices. None had kickstands or means to orient them to the sun properly, so you’ll have to get a little more creative, like propping them up on a rock, attaching them to your tent, or attaching them to your backpack to orient them properly to get the most power out of them in camp.
The Big Blue did better than the competition in tests, producing just under 950 milliamp-hours (mAh) of energy in an hour. In relatively similar conditions, the Anker produced 733 mAh, and the Nekteck produced 834 mAh. Without a dedicated test facility and control environment, it is hard to offer a complete scientific evaluation of the differences between these three since clouds could have obscured the sun for part of the testing periods.
In our experience, the Big Blue (or other similar solar panels) will integrate best into your outdoor lifestyle with the help of an external battery, like the Anker. The solar panel charges the battery, and then the battery provides a steady charge to reliably and safely charge your phone. See our section below on batteries for more details.
The Big Blue offered the highest power output among these three, and its cost is essentially the same as the Nekteck, so The Big Blue edged out the Nekteck as the best solar charger. It’s easy to use, well-priced, and offers enough portable power to charge a backup battery. Best yet, it is rugged enough to last for years.
Interested in backpacking gear? See our Backpacking section for our most popular stories.
The Best Solar Charger for Camping: Goal Zero Nomad 50
The Best Solar Charger for Basecamping: Goal Zero Nomad 50
Weight: 6 pounds
Solar Cell Output Capacity: 50 watts
Power Output to Device: USB: 5V up to 2.4A (12W max)/8mm: 14-22V, up to 3.5A (50W Max)
Foldable: Yes
Integrated battery: Goal Zero Sherpa 100 AC sold separately
Ports: 1 2.4 Amp USB-A Port, 1, 3.3 Amp Solar Port in 8mm, 1, 3.3 Amp Solar Port out 8mm
What we liked: can be linked with other solar panels for even greater charging, kickstands to properly orient to sun, can almost fully charge 2 laptops
What we didn’t like: size and weight make best suited for camping, not backpacking
The Goal Zero Nomad 50 is a larger solar charger that also wins our award for Best Solar Charger for Car Camping and Best Solar Charger for Basecamping and our Best Upgrade Solar Charger award. At 50 watts, it’s the biggest and heaviest solar charger we tried. But if we were doing a couple of weeks in a high mountain cirque with fellow adventurers and we wanted to cut battery weight while keeping our electronics charged, this is the charger we’d choose.
Likewise, if we’re powering all the devices a family needs on a week-long camping trip and they don’t want to drain a car or RV battery, we’d turn to the Goal Zero as our solar charger of choice. Similarly, it’s a good choice for road tripping or overlanding off-grid. It could also be used to work a remote aid station during an ultramarathon or adventure race.
Compare Prices on the Goal Zero Nomad 50
We tested charging an iPad with the Goal Zero Nomad. The Nomad 50 is the only solar charger we considered that has kickstands to angle the panels to the best angle to charge.
The Goal Zero is an obvious choice for camping and basecamping for other reasons as well. It’s the only solar charger we evaluated that can be linked to other solar panels and the only one that can be attached in a series to provide even greater charging power to a battery power bank.
With solar cells covered in a polymer and the whole unit encased in a durable polyester, the Nomad is like the larger sibling of the three clones (Big Blue, Anker, and Nektek).
Instead of two cells per foldable solar panel, each of its four panels has 12 cells. It has one USB connector that can provide up to 12 watts of charging power, but it also has a Goal Zero solar port connector that allows it to provide up to 50 watts of charging power or connect to other Goal Zero panels. Like the BioLite solar charger, the Nomad also has kickstands to help ensure it’s properly oriented to the sun.
The entire length of the unfurled Goal Zero Nomad 50, which folds up neatly to the size of a single panel for easy transport.
All of those extra features and solar cells add weight and size. Unlike the clones, the Nomad 50 would take up a significant portion of a backpack.
Folded up, it’s almost a foot wide and nearly 1 foot and a half tall. That’s roughly the size of an average male’s torso, and it weighs 6 pounds, 14 ounces. Even if it were attached to the front of Frankenstein’s backpack, it would likely drag on the ground like an oddly stiff cape.
But once unfurled and set up in camp, it can provide enough energy to power a laptop and charge a significantly larger battery than the smaller chargers can power.
When combined with a Goal Zero’s Sherpa 100AC power bank, it can charge in 6 or fewer hours in good sun. That 94.7 watt/hour battery includes an inverter allowing it to charge AC devices, like those that plug into a wall outlet. It can almost fully charge two 13” MacBook Pros on a single charge, and since it can deliver at higher wattages and voltages, it can provide higher charging speeds.
Interested in camping gear? See our Camping section for our most popular stories.
The Best Solar Charger with Integrated Battery: Biolite SolarPanel 10+
Weight: 1 pound, 3.4 ounces
Solar Cell Output Capacity: 10 W
Battery Storage Capacity (mAH): 3,200 milliamp hours
Power Output to Device: 10 W via USB charge out
Foldable: Yes
Integrated battery: Yes, Battery Storage Capacity (mAH): 3,200 milliamp hours
Ports: 1 Micro USB in & 1 2.4 Amp USB-A out
What we liked: includes integrated battery that works as power bank, can pre-charge included powerbank, easy to align with sun to get the most efficient charge, designed to reduce overheating (that impacts efficiency)
What we didn’t like: would be more useful if it were 21W and had storage 10,000 mAH
Though the BioLite SolarPanel 10+ is the smallest solar charger we tested at just 10 watts, it’s the most fully featured and the only solar charger we tested that came with an integrated battery that works as a power bank.
The 3,200 mAh battery is slightly larger than my iPhone 11’s 3100 mAh battery and could provide an iPhone with a full charge. You can also charge the integrated battery power bank via micro-USB. So users can pre-charge it for adventures so they can charge devices at camp even if the sun’s obscured or down when they get there. Indeed, starting every adventure with fully charged devices and auxiliary batteries is key to getting the most out of your electronic charging system in the backcountry.
COMPARE PRICES OF THE BIOLITE SOLARPANEL 10+
Unlike the other portable solar panels we tested, the BioLite Solar Panel 10+ encases its solar cels in a rugged, dimpled plastic to dissipate excess heat.
The SolarPanel 10+ also has a radically different design than every other portable panel we tested and most others available. All of its solar cells are encased in a ruggedized, dimpled plastic. BioLite says its solar panel design helps dissipate excess heat, which can cause a solar panel to produce less power than it otherwise would.
Like the other small solar chargers we evaluated, the corners feature holes allowing users to attach them to a backpack or tent. But its analog Optimal Sun System, consisting of an analog sundial, as well as its rotating kickstand, play an important part in making sure you get the most from the charger at any given time.
By aligning the shadow of the dot in the middle of the window, you ensure that the device sends as much solar power to connected devices and the battery as possible. The kickstand clicks into place throughout its rotation, making it easy to adjust the pitch of the portable solar panel to get the optimal placement at any given time.
While we found all these features very useful, we found that when first deploying the solar panel, it didn’t want to stay open until after it warmed in the sun a bit. Also, if its ability to absorb sunlight was larger — even in the 21 watt range — and its energy storage capacity was larger, even around 10,000 mAh, it could have been the Overall Winner.
Other solar panels we tested
Both the Anker portable charger and Nekteck portable charger fell a little short of the Big Blue, our overall winner (see review above). Either offer a great value, but we think the Big Blue has the most to offer for the money.
Anker 21 Watt Powerport Solar Charger
Weight: 14.7 ounces
Solar Cell Output Capacity: 21W
Power Output to Device: 21W to device via USB
Foldable: Yes
Integrated battery: No
Ports: 2, 2.4 Amp USB-A Ports
The now discontinued Anker 21 Watt PowerPort Solar Charger may no longer be available, but we think it’s worth putting on your radar for a few reasons.
First, it’s a near-clone of the Big Blue (see review above), our overall winner, so it’s a good example of the similarities between solar panels on the market. Second, it is still widely available on sites such as ebay for folks interested in buying a used solar panel.
One difference is that it was slightly smaller and lighter (15 ounces) than the Big Blue. The Anker produced a little less power in a given time in similar conditions, as expected. Its charging pouch also had a hook-and-loop closure rather than a zippered closure like the other clones. It didn’t include an ammeter. Ultimately, even when the Anker was available, we found the Big Blue to be a better choice given the amount of power it generated.
Nekteck 28 Watt Solar Charger
Weight: 1.44 pounds
Solar Cell Output Capacity: 28W
Power Output to Device: 28W via USB
Foldable: Yes
Integrated battery: No
Ports: 2, 2.4 Amp USB-A Ports
Without the branding, from the outside, the now discontinued Nekteck 28 Watt solar charger is essentially indistinguishable from the Big Blue, our overall winner (see review above). The specs are similar. Opened up, and without the ammeter, they look essentially identical, too.
However, in the end, it didn’t perform quite as well as the Big Blue — even though it uses the same solar cells and design. In relatively similar conditions, the Anker produced 733 mAh, and the Nekteck produced 834 mAh. It also has a claimed weight of 1 pound, 7 ounces — two ounces heavier than the Big Blue.
Understanding Solar Chargers
Comparing solar panels side-by-side. Here, we’re charging wireless earbuds, a satellite emergency messaging device, and a headlamp.
There’s a lot to understand about solar power chargers, but at their heart, a small solar panel consists of several photovoltaic cells grouped together to absorb some of the sun’s energy and convert it into an electric charge that you can use to charge electronics.
Modern, commercially available solar cells can harness nearly 25 percent of the sun’s energy that hits them into electricity. You’ll find this in the most efficient foldable chargers. When these cells are combined together into small solar panels, the solar cells can provide enough energy to recharge the batteries in USB devices and they can weigh under a pound, making them a lightweight option for backcountry adventures across the world.
Why choose a solar generator over other choices?
A portable solar charger is a lightweight and more compact means of electricity generation compared with other means of mobile energy generation. This is advantageous when on the trail and in remote locations because carrying multiple batteries and other means of electricity generation quickly becomes cumbersome as you add more energy storage to your pack. After all, no one wants to carry a gas generator — and gas — on their backs into the woods to provide power for all of their electronic devices. And while we’ve seen some portable wind and micro-hydro turbine generators, like the WaterLily Turbine, they’re also cumbersome, if not heavy. Solar panels are among eco-friendly gear swaps to reduce your environmental impact, especially if your base camp would otherwise run on a gas generator.
Solar chargers, combined with a power bank or backup battery pack — particularly those that can accommodate through charging (i.e., charging itself while charging devices) — are the best, lightest way to charge your electronic equipment.
While most adventurers are looking primarily for a portable phone charger, solar chargers can power:
Rugged cameras and camera batteries
Action cameras like the GoPro Hero 12 Black and Instant360 Action camera, and other vlogging or podcasting equipment
two-way satellite messengers and Personal Locator Beacons (PLBs)
ebooks
tablets
laptops
bluetooth speakers
SteriPens
sonar devices
Anytime you’re out for multiple days or weeks in the backcountry, you’ll likely have electronics that need charging. Solar panels work for camping, boating, climbing, bikepacking, mountaineering, and other activities.
Most mobile solar charging units have at least one USB port, making it easy to charge most devices and batteries people take into the wild. Still, many smaller solar chargers will struggle to provide enough power to charge multiple devices simultaneously.
Why Watts Matter
Yes, Watson, Watts Matter.
The most important thing about a solar panel charger is its wattage. The more watts, the more sunlight the solar panel can absorb and the more electricity it can generate. If you only need to power your own devices and don’t plan on using them continually while on the trail, you may only need to charge them once every few days or even once a week. In that case, a smaller unit like the BioLite SolarPanel 10+ with an integrated battery pack is an excellent choice, but the 10 watt foldable solar panel only has one USB port and wouldn't be powerful enough to charge a family’s devices on a five-day trip.
The Sherpa 100 AC power bank works with the goal zero nomad 50 solar panel to handle the needs of a week-long trip
On the other hand, our Best for Camping winner, the 50 Watt Goal Zero Nomad 50 Solar Panel, along with the Sherpa 100 AC battery, could handle the needs of a family on a week-long trip or a group of mountaineers exploring a range out for an extended period.
The Goal Zero system is significantly larger, heavier, and much more expensive. But this system with this power bank battery has an AC plug and is the only one we considered that charges devices such as large laptops.
We don’t normally advocate getting rid of gear before its end of life, but in this case, if you have a backup battery or power bank that isn’t chargeable via USB, consider recycling it and replacing it with one that is. Similarly, consider USB chargeable devices like headlamps.
While you can use rechargeable AA and AAA powered headlamps, using one device or cable to charge most of your equipment can simplify your carry. When Intel's Chief Systems Technologist Ajay Bhatt led the development of USB standards in 1996 and companies started using it, he essentially began a process of universalizing charging and connectivity for all devices. Now, USB technology allows us to easily recharge cameras and GoPros as well as smaller electronics like wireless earbuds.
How we researched and tested
Research
Comparing solar panels and solar chargers in a field test.
When researching the best camping solar chargers, we explored websites in the outdoor media sphere, and the tech and science spheres as geeks and gear heads are the most likely to use portable solar chargers to power their electronics.
We chose the models we tested based on reviews and articles we read and analyzed from other reliable sources, including Lifewire, Gear Institute, Backpacker, Wirecutter, The Adventure Junkies, Popular Mechanics, Outdoor GearLab, and others (see Sources). We also looked at verified customer reviews to gather data from professional reviewers and actual users.
We tested foldable solar panels in the field at campsites and also at home using a USB digital tester (shown here).
How We Tested
We tested these foldable solar panels on multiple days in the field, at campsites, and at home, sometimes even hanging them out of a south-facing window on sunny days of full Colorado summer sunshine. Despite multiple uses and attempts, none of the solar chargers we tested reached the manufacturer’s claimed fully-rated wattages for maximum power output during our tests.
We attached each solar panel to a USB digital tester and various battery packs and other electronic devices we use in the backcountry, including GPS units, Bluetooth headphones, bike lights, headlamps, and more. We attempted to charge our iPhones and iPads directly but found they wouldn’t accept the charge since the power varied too much with the sun and clouds — even on some bluebird days. We found it was better to use them to charge a backup battery or power bank with through charging capabilities and then use that battery to charge our devices while it was charging via the solar panel.
We attempted to test some of the chargers while hiking but found that even though companies place attachment points on the solar chargers to attach them to backpacks, they didn’t perform well in real-world testing that way. We’ll explain why in another section.
We found that the digital USB tester wasn’t as applicable to the Goal Zero and BioLite contenders. This is because we couldn’t connect the digital USB tester to the higher wattage power cord of the Goal Zero, and the BioLite’s solar charge controller and portable battery power bank can provide a more conditioned stream of power from the battery.
A more permanent solar panel set-up near Zion National Park. Photo by Jeremy Bezanger on Unsplash
Buying advice
When looking for a good solar charger, there are many things to consider. First and foremost, you’ll want to determine what you’ll use it for as well as how many devices it will power. Secondly, consider how long you’ll be in the backcountry and how much energy storage and battery capacity you want to carry.
We looked at a wide range of solar chargers and, in some cases, energy storage units (aka batteries). We also came up with some different conclusions than other review sites based on our knowledge and our anticipation of how you’ll actually be able to use a solar charger in the field.
For instance, unlike many other reviews and ‘best of’ lists we evaluated, we firmly recommend using solar chargers with backup batteries. Many high-end electronics like smartphones and tablets require a steady, regulated, or conditioned stream of electricity to charge. It helps limit the amount of damage that a surge or dip in solar power can do to the sensitive electronics inside the device.
Efficiency and power output
Efficiency and power output are two separate, but related, things. Efficiency refers to the efficiency of the solar cells in a panel and also the panel itself. The solar cells in the panel have a higher efficiency than the overall panel as some of the energy they capture is lost in transmitting energy through the wires and electronics of the solar panel. The most efficient commercial solar cells are around 24 percent efficient. A solar panel or charger, however will likely be in the range of 18 to 21 percent efficient.
Power output is measured in terms of wattage or how many watts of energy a solar panel can output. The more efficient a solar panel is means it can output more watts and amps from a smaller area. For charging devices you’ll want a solar panel that’s capable of producing at least 5 watts, however many highly portable solar panels produce up to 28 watts of charging power in ideal conditions. Higher wattages do equal more charging power—however, since most of these solar panels still use USB-A style plugs, they can only produce 2.4 amps of current through those plugs.
Portability and size
The smallest outdoor solar panels we evaluated are 5 watts. These are about the size of a medium tablet, like the BioLite SolarPanel 5+, and weigh less than a can of beer. They can produce enough power to slowly charge a smartphone or other device. At 8 inches by 9.75 inches, they’re easy to slip into a day pack.
The largest portable solar panel we tested was the 6 pound Goal Zero Nomad 50, which folds down to just over 17 inches long by 11 inches wide and is well over an inch thick at its thickest parts, making it hard to fit in most backpacks. When set up it folds out to 53 inches wide. It was also the most powerful solar panel we tested and is capable of charging a battery that can charge laptops.
Durability and weather resistance
While these panels will last for years and even decades with proper care, they’re not designed to be left out in the elements like a permanent installation. They are encased in abrasion-resistant fabrics and plastics and are foldable.
The solar cells are encased in impact-resistant plastic and the units usually have an IPX4 water-resistant rating, meaning they can handle water splashes but not much more than that. That shouldn’t be a surprise since the majority of portable solar panels have standard USB-A ports with no waterproof cover.
Battery capacity
The majority of the solar panels tested don’t have batteries. The BioLite SolarPanel 5+ and BioLite SolarPanel 10+ have 3,200 mAh batteries. That’s enough to charge an iPhone 13 or 14 one time. You can also pre-charge these batteries before you leave and use them to charge a device while it’s in your pack or at night and recharge the battery with the sun.
Direct solar charging speed
If the solar panel is optimally placed in full sun it should be able to produce its maximum wattage rating. In these cases, a panel like the Anker 21 Watt PowerPort Solar Charger should be able to provide enough energy to charge 2 USB devices simultaneously at 2.4 amps, the same as many 12-Volt USB adapters used in cars.
Multiple device solar charging speed
In ideal, full-sun conditions a 20 or more watt solar charger with two (or more) USB ports should be able to charge multiple devices at up to 2.4 amps like most 12-Volt USB adapters used in cars. A more powerful panel should be able to charge more, but the device has to be able to handle higher charging amperages like those that use USB-C connections.
Additional features and accessories
The majority of portable solar panels for camping are pretty minimal in terms of features. Most consist primarily of the panel and USB ports. Additional features include a pocket for cables, grommets or loops to attach the panels to a pack or tent, and on some, stands to help keep the panel upright and at the right angle. A few, like the BioLite panels, have integrated batteries and they also have a little sundial that helps users properly orient the panel so that optimum sun hits the solar cells.
When it comes to accessories, there are two main accessories you can use with the solar panels, cords and batteries.
We highly recommend using these with a backup battery rather than plugging a smart device directly to them. Some smart devices limit the speed at which the devices can charge when dealing with a variable power source, like a solar panel. Backup batteries, however, can better harvest the variable currents flowing from a solar panel.
Price and value for your money
The price of basic solar panels isn’t very high, about $70 for our Best Overall pick, the Big Blue 28W USB Solar Charger. If you have an existing backup battery and know you’ll be camping out for days and need extra power for your electronics when camp is set up, it’s a decent investment.
If you’re hoping it’ll power your devices while strapped to the outside of your pack and hiking, you’ll be displeased. Despite advertising photos, even in sunny Colorado where we tested all the devices, these panels weren’t great at delivering power consistent enough to charge devices while hiking with them on a pack.
Integrated Battery or power bank
Unlike many other reviews and ‘best of’ lists we evaluated, we firmly recommend using solar chargers with backup batteries. Many high-end electronics like smartphones and tablets require a steady, regulated, or conditioned stream of electricity to charge. It helps limit the amount of damage that a surge or dip in solar power can do to the sensitive electronics inside the device.
In addition, carrying a pre-charged backup battery or power bank and a way to easily charge all your devices when you’re in town or your vehicle can reduce the amount of charging you’ll need to do on the trail. Pre-charging or recharging a backup battery or power bank via the wall or your vehicle will almost always be faster than charging via a solar panel.
The other two models we evaluated cost more. The BioLite, which is only a 10 watt solar panel, retails for $150. However, it’s also the only solar charger we tested with an integrated battery (sometimes called a portable solar power bank). It also has a kickstand, and a unique but simple mechanism called the Optimal Sun System, which helps orient the charger to get the maximum amount of sunlight available. It’s also unique in that it’s encased entirely in plastic.
The Goal Zero Nomad 50 Solar Panel, our winner for Best Solar Charger for camping (see review above) had the highest wattage of any unit we tested at 50 watts and was the most expensive unit we tested at $250. It was also the largest and heaviest, but it is the only one that can provide a charge at a higher wattage and voltage.
With panels this small, when the skies are gray, don’t expect much power output. The 50 watt, Goal Zero Nomad 50 should still produce enough energy to trickle-charge a smartphone but smaller panels will slow down to producing very small amounts of power, suitable only for trickle charging a backup battery.
Types of solar cells
The types of solar cells in a solar panel also matter. Though we only recommended portable solar panels that used monocrystalline silicon solar cells, some solar chargers use polycrystalline silicon solar cells or even thin-film solar cells. A monocrystalline panel consists of monocrystalline solar cells, which are currently the most efficient commercially available solar cells. A polycrystalline solar panel is made of polycrystalline cells.
While some thin-film solar cells have the advantage of flexibility and are often more lightweight, they’re less efficient. This means you need a larger surface area to absorb as much sun and produce the same wattage or charge that a monocrystalline solar cell does.
For each monocrystalline solar panel we recommend, we did hands-on testing. As such, it’s no surprise that both the 28 Watt BigBlue solar charger retails for about $70 while the slightly smaller 21 Watt Anker solar retails for less (if you can find it). One advantage of solar panels is they seem to become less expensive year after year as the technology improves.
Is solar power good for the environment?
The whole world is starting to look at solar power as a more viable way to power our lives. That’s because solar’s environmental footprint is less than most other forms of power generation.
While some have criticized both the energy cost of making solar cells and the use of certain materials in their production, it’s becoming clear that solar panels produce more energy than is used to create them.
In fact, solar panels have been more efficient than other forms of electricity since at least 2013. They last up to 20 or more years in the field, and most, if not all, components of solar panels are recyclable.
With that said, regularly used portable solar power chargers probably won’t last 20 or more years without seeing significant failure. It’s tough to tell because they largely haven’t been in use for that long. Still, when compared to using disposable batteries, you’ll get far more life out of the solar chargers, and their use will pay back the amount of energy used to create them. We recommend recycling your solar chargers at the end of life and anticipate that they may last for up to 10 years with regular use.
By the time a solar battery charger does fail, it’s quite likely that newer solar chargers will be much more efficient and lightweight as new technologies continue to make solar power more efficient, lightweight, easy to produce, and less impactful on the environment.
FAQ
Do solar chargers still work on cloudy days?
Smaller solar charger or panels don’t deliver enough power to charge devices on cloudy days effectively. A larger panel, like the Goal Zero Nomad 50 should still be able to deliver enough power to charge a device on a cloudy day. Solar chargers or solar battery banks, with on-board energy storage, like the BioLite + series, can if the solar panel was previously charged by the sun or at home.
Do portable solar chargers work?
Yes. In good sun and when properly oriented portable solar panels do work well.
How many amps solar charger do I need?
Most people want a solar panel or charger that can deliver at least 2.4 amps, which is the power needed to charge a USB device.
What is the difference between a solar charger and a solar power bank?
A solar charger consists of a solar panel and means to harvest the energy produced via cables or ports. A solar power bank allows you to ‘bank’ the sun’s energy. It includes an energy storage component—a battery—either as part of the panel or externally.
How to choose the best solar panels for you
The best solar panel for you will depend on whether you are camping, backpacking, or base camping. It will also depend on the size of your group a you may find one of these portable, foldable, solar chagrers to suit your needs better.
When considering a solar charger, you need to consider how and what you’ll use it for and how many people are likely to need power from it for their devices. Before choosing a solar panel and power bank, ask yourself the following questions:
What type of trips will I use it on?
If it’s just you and a buddy going out for a weekend of backpacking or bikepacking, you’re probably only going to need the Big Blue or the BioLite SolarPanel 10+.
If you’re out for a weekend, unless you’re running a lot of devices, you’re probably not going to need a whole lot of solar charging. With the backup battery capacity of the BioLite 10+ and its photovoltaic charging ability, its ability to provide solar power will rival that of the Big Blue for the weekend.
How many people will need to use it?
If you’re going on a major trip with a group and are going to be away from civilization and access to other power sources for more than four or five days, like a backcountry bikepacking or climbing expedition, and want to do a lot of videography and documentation, you’re going to have different needs than someone on a solo trip.
Likewise, if your family is going out with a pop-up tent for two weeks and you want to charge all your and your kids’ devices without firing up the car, consider investing in a larger unit like the Goal Zero Nomad 50, our Best Solar Charger for Camping (review above).
Also, consider getting an advanced battery pack with an AC inverter like the Goal Zero Sherpa 100AC. You could even plug a Dometic backcountry friendly refrigerator and cooler into it.
For example, if you’re on a Solo Road Trip, your needs will likely be less than if you’re on a family RV or vanlife style road tripping for multiple months off grid.
Tips for maximizing the efficiency of your solar charger
We know, we know, we know, you’ve seen the pictures of solar chargers strapped to the front of backpacks, like they’re actually charging your devices while you’re on the move. That’s the ideal, right? But it’s not necessarily the reality.
For a solar charger to produce optimal power while hiking, you’d have to be hiking primarily northbound in the northern hemisphere and primarily southbound in the southern hemisphere — all day, in direct sunlight, and without any shadows from trees or clouds. You’ll meet these conditions in desert or snowfield hiking.
You’d also want to shift them east to west across your pack with the sun’s movement or find a trail that slowly moves from west to east to orient the panels throughout the day properly. Then you might also have to keep your back arched at a certain angle to maintain the best angle orientation throughout the day.
Bottom line — you’re not going to get a lot of solar power from a solar charger while carrying your solar panel on your pack (even if it looks cool in advertising photos). However, during the daytime in camp, they’re great. You can lay them on the ground, and they’ll produce energy, but angling them to the sun without movement will net you far more energy.
How to charge a solar panel for use in the outdoors
Set them up toward the sun and, if propping them up on rocks or sticks, try to minimize the shadows beneath them. You can also attach them to your tent or on the front of your backpack — just orient them so they cast the smallest shadow.
If you’re setting and forgetting them while going out on day trips and leaving them connected to a battery, the best angle to set them at in most of the US is around 37 degrees. That’s just shy of the angle needed for an equilateral triangle. If you’re in the southern US, make the angle shallower. If you’re in the northern US, make it steeper. You can eyeball the angle, or you can use a compass or a level app on your smartphone to help determine the angle at which you’re setting it. If you lay it flat on the ground, it will generate slightly less power.
Solar panel accessories
Hiking watches with their respective chargers are common items that need to be charged in the field.
We’ve stated earlier in the piece that you should use these solar panels with a backup battery or power bank; we're reiterating that here.
Batteries
The real reason to use a solar charger is to help you cut the number of backup batteries you’ll need on a more extended trip or with multiple people to charge your electronics. That, in turn, helps cut back on the weight you need to carry into the wilderness.
Although you could hook your panel right up to your phone, when a cloud comes or sun angle changes, phones often interpret that as “I’m no longer plugged in.” Even when the sun comes back, most phones can’t recognize the charge connection has returned without a human plugging the cord back in. Batteries, in contrast, don’t shut off the charge when they receive low input.
When it comes to choosing a backup battery, make sure it’s rugged enough to handle being tossed around and ideally has at least some water resistance rating. It should be big enough to provide enough power to fully charge your most important device and ideally two or three others, just in case you hike through a patch of rainy days.
Likewise, choose a battery or power bank with through charging capability that is chargeable via a USB and ideally a micro-USB cable. These cables are easy to find, work with solar chargers, and are inexpensive.
While shorter cables are lighter, the difference is often negligible, even for the most conscious gram counters. Make sure your cords are long enough so that you're not tied within inches of the solar charger or your battery while you’re using them.
charging block
A charging block allows you to charge multiple USB devices at once. While typical chargers run at 5 W, many charging blocks (also called power adapter) can run at 20W. The result is a much faster charge of devices.
About the Author/ Why You Should Trust Us
The author, Chris Meehan, in his happy place.
As an outdoors writer covering adventure and gear, I have contributed multiple “best” guides to Treeline Review, and am a regular contributor to Backpacker and other outdoor publications and organizations.
In addition to writing about the outdoors, I have also written about solar and renewable energy for the past decade. I have gained a lot of knowledge about how solar power and photovoltaics work and what they can and cannot do.
I have written multiple outdoor guidebooks. My most recent Falcon Guide, Colorado’s Best Front Range Adventures: The Greatest Hiking, Climbing, Paddling and More From Denver to Colorado Springs and Fort Collins. In it, I cover the best hiking, biking, climbing, and rafting in the region.
I’m also the author of Falcon Guide’s “Climbing Colorado's Fourteeners: From the Easiest Hikes to the Most Challenging Climbs” and edited Justin Lichter’s excellent guide to thru-hiking titled Trail Tested: A Thru-Hiker's Guide To Ultralight Hiking And Backpacking. All of this experience has helped me become a first-rate gearhead and product tester.
Overall, I have 20-plus years of exploring, mountain biking, hiking, backpacking, climbing, guiding, and playing in the wild. I worked with National Geographic and their mapping division in developing their Colorado 14ers Map Pack Bundle. I’ve written about hiking and climbing for Elevation Outdoors, including stories about Colorado 14ers and outdoor apps to boost adventures.
I’ve written about countless outdoor companies, outdoor sports, and tested gear with publications including CompanyWeek, Outdoor USA Magazine (print), Elevation Outdoors, 5280, and more.
I am not sponsored by any companies, nor are any of my family members working for, serving as ambassadors for, or sponsored by any of the companies mentioned in this review. At Treeline Review, we strive to offer unbiased reviews to help you find the best product for the price. Treeline Review doesn’t accept sponsored content, native advertising, or paid reviews.
You can read all of Chris’s Treeline Review stories on his author page.
