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Best Portable Solar Charger of 2021

Photo: Jane Jackso n
By Jane Jackson ⋅ Senior Review Editor
Friday February 5, 2021
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Ready to join the solar revolution? After spending 9 years testing 80+ models, we know a thing or two about the contenders that offer up the highest performance. We've purchased 10 for our 2021 update, subjecting them to exhaustive side-by-side testing across a range of metrics, such as charging speed and weight. From 40W behemoths to panels with battery packs, we've had our hands on a wide variety, testing them while car camping, in the backcountry, and on the side of rock climbing walls. Our review is a culmination of our expertise, and we highlight budget-oriented models, special niche products, and the cream of the crop.

Top 10 Product Ratings

Displaying 1 - 5 of 10
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Awards Top Pick Award Editors' Choice Award  Best Buy Award Top Pick Award 
Price $79.95 at Amazon$69.96 at Amazon$69.99 at Amazon$46.99 at Amazon$125.93 at REI
Overall Score
74
80
79
79
67
Star Rating
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Pros Durable, well-designed, fast charging timesInexpensive, efficient, user-friendly, excels in partly cloudy conditionsEfficient, powerful, great value for its size, lightweightQuick to charge, portable size, panel actually works despite small wattageSmart design, built in battery maintains charge through intermittent shade/sun, durable
Cons Expensive, bulkyBulky, heaviest weightPocket too small to hold extra cords and accessoriesHeavy, slow to replenish battery via solarExpensive, heats up when left in sun for long periods
Bottom Line Provides quick charge times, a durable design, and a roomy mesh pocketFor an inexpensive, easy-to-use and efficient panel, the BigBlue is a no-brainerThis panel is efficient in varying conditions and can charge multiple devicesFor a small battery pack with solar capabilities, this is an impressive productWith a smart design and high scores in overall performance, this panel impressed us
Rating Categories SunJack 25W BigBlue 28W Anker PowerPort 21W Goertek 25,000mAh BioLite SolarPanel 10+
Charging Speed (30%)  
9
9
8
8
8
Charge Interruption Recovery (20%)
7
9
8
8
8
Multiple Device Charging Speed (20%)
9
9
9
9
2
Weight & Portability (20%)
3
5
7
7
7
Durability (10%)
9
7
7
7
9
Specs SunJack 25W BigBlue 28W Anker PowerPort 21W Goertek 25,000mAh BioLite SolarPanel...
Panel Size (watts) 25W 28W 21W 5W 10W
Weight (measured) 30.1 oz 23.5 oz 17.6 oz 19 oz 19.2 oz
# of USB outlets 2 2 2 3 1
Max USB Output Current (amps per port) 2 amp 2 amp 2 amp 1 amp 2 amp
Battery kit? Yes No No Yes No
Size folded 12.6" x 7.8" x .8" 11.1" x 6.3" x 1.3" 11" x 6.3" x .75" 7" x 3.75" x 1.25" 10.1" x 8.2" x 0.94"
Battery? Yes No No Yes No
Charge tablet? Yes Yes Yes No Yes
Charge laptop? Yes Yes Yes No No
Panel Type ETFE PET Polymer Mono-crystalline Mono-crystalline Mono-crystalline
Size opened 24.6" x 7.8" x .8" 33.1" x 11.1" x 0.2" 26.3" x 11.1" x 0.2" 7" x 3.75" x 1.25" 20.3" x 8.2" x .4"
Battery input (Volts / Amps) 5V 2A N/a N/a 5V 2A N/a
Charge capacity (mAh) 10,000mAh (x2) N/a N/a 25,000mAh N/a
Charge iPhone/smartphone Yes Yes Yes Yes Yes
Direct USB Plug? Yes Yes Yes Yes Yes
Daisy Chain? Yes No No No No
12-Volt connection Yes No No No No
Warranty 1 year 2 years 18 months 1 year Limited lifetime

Best Overall Solar Charger


BigBlue 28W


BigBlue 28W
Editors' Choice Award

$69.96
(13% off)
at Amazon
See It

80
OVERALL
SCORE
  • Charging Speed - 30% 9
  • Charge Interruption Recovery - 20% 9
  • Multiple Device Charging Speed - 20% 9
  • Weight & Portability - 20% 5
  • Durability - 10% 7
Weight: 23.5 oz | Number of USB outlets: 2
Efficient
Functions in marginal conditions
Built-in ammeter and auto-restart function
Struggles to charge multiple devices
Bulky

The Big Blue 28W goes above and beyond the rest in terms of overall performance. This panel is the most consistent and efficient portable power source we've reviewed. Though there may be other options out there that charge faster or look flashier, nothing beats this model when it comes to overall performance. When your electronics need a boost, this panel will deliver a substantial charge in various conditions. In terms of features, we love the built-in ammeter and the zippered accessory pouch. We also appreciate this panel's simplicity and reasonable price tag. With two USB ports and a classic fold-out design, the BigBlue is an excellent all-arounder that will efficiently charge most small gadgets.

One downside to this panel is its weight. It's a bit heavy, weighing in at 23.5 ounces. As a result, it's better suited for frontcountry use, though it will excel wherever you bring it. Other than that, this panel receives high marks across the board.

Read review: BigBlue 28W

Best Bang for the Buck


ECEEN 13W


ECEEN 13W
Best Buy Award

$39.99
at Amazon
See It

70
OVERALL
SCORE
  • Charging Speed - 30% 8
  • Charge Interruption Recovery - 20% 6
  • Multiple Device Charging Speed - 20% 4
  • Weight & Portability - 20% 9
  • Durability - 10% 8
Weight: 12 oz | Number of USB outlets: 2
Reasonable price tag
Lightweight
Simple design
Fast charging capabilities
Clip-in points lack durability
Can't charge multiple devices effectively

The ECEEN 13W grabs our attention with its simple design, consistent performance, and, of course, its affordable price tag. Its small size and sleek shape make it a good option for backcountry use. This panel is easy to use and fairly compact, plus it charged our small battery packs and phone almost as quickly as panels with much larger capacities. The combination of high-performance and a reasonable price tag makes this panel a no brainer!

In some ways, we loved the simplicity of this panel. Its design is portable and easy to use, but it struggles to charge in partially cloudy conditions, and it can barely charge multiple devices simultaneously. Thirteen watts is relatively small when charging large, power-hungry devices, so keep that in mind when considering this panel.

Read review: ECEEN 13W

Another Excellent Value


Goertek 25,000mAh


Goertek 25,000mAh
Best Buy Award

$46.99
(6% off)
at Amazon
See It

79
OVERALL
SCORE
  • Charging Speed - 30% 8
  • Charge Interruption Recovery - 20% 8
  • Multiple Device Charging Speed - 20% 9
  • Weight & Portability - 20% 7
  • Durability - 10% 7
Weight: 19 oz | Number of USB outlets: 3
Reasonably priced
Portable size
Functioning solar panel, despite size
Fast charging capabilities
Heavy
Hard to replenish battery via solar

The Goertek 25,000mAh battery pack is a high capacity battery with three USB ports that deliver rapid charge to small electronics. We love that it has a large capacity and can fully charge a phone multiple times when the battery is topped off. Additionally, the small solar panel on its back works well enough for the battery to replenish using solar, even if it takes a few hours. In addition to all these great features, the Goertek rings in as one of the most reasonably priced options for solar charger set-ups.

Our issues with this battery pack are similar to the problems we've had with other battery pack/solar options — patience is required. This product does not work great as a solar charger alone; if you're planning to fully charge the 25,000mAh battery off the sun, give yourself a few full days. That said, the panel will continue to trickle charge the battery pack, even when small electronics are plugged in, which is a feature that we appreciate.

Read review: Goertek Solar

Best for Durable Performance


BioLite SolarPanel 10+


BioLite SolarPanel 10+
Top Pick Award

$125.93
(10% off)
at REI
See It

67
OVERALL
SCORE
  • Charging Speed - 30% 8
  • Charge Interruption Recovery - 20% 8
  • Multiple Device Charging Speed - 20% 2
  • Weight & Portability - 20% 7
  • Durability - 10% 9
Weight: 19.2 oz | Number of USB outlets: 1
Sleek design
Durable construction
Portable size and shape
Built-in battery adds efficiency
No storage pocket
Expensive

The BioLite 10+ is notable for its durability and portability. Its rugged construction makes it incredibly reliable, as does its hidden built-in battery pack. The battery regulates charge, so the panel works reasonably well in sub-optimal charging conditions. We liked the kickstand and fold-out design, as it's sleek and portable enough to fit into our backpacks on most light and fast missions.

The major downside to the BioLite is its price tag; this panel and its name-brand recognition come at a price. For us, its durability and overall performance outweigh the initial investment, but it's something to consider. There are plenty of less durable panels out there that will perform well, but few can stand up in terms of overall design and construction.

Read review: BioLite 10+

Excellent Lightning Fast Charging Speeds


SunJack 25W


SunJack 25W
Top Pick Award

$79.95
(33% off)
at Amazon
See It

74
OVERALL
SCORE
  • Charging Speed - 30% 9
  • Charge Interruption Recovery - 20% 7
  • Multiple Device Charging Speed - 20% 9
  • Weight & Portability - 20% 3
  • Durability - 10% 9
Weight: 30.1 oz | Number of USB outlets: 2
Durable construction
Thoughtful design with great storage pocket
Very fast charging speeds
Works well in marginal conditions
Expensive
Bulky

Though it is doesn't have the highest listed wattage of any panel in this review, the SunJack 25W wowed us with its impressive performance. It rapidly charged our cell phones, external battery packs, and other random electronic gadgets with ease. It boasts some of the fastest charging speeds we've seen in testing. Plus, its impressive build and durable construction are confidence-inspiring. It also performed well when partially shaded, or in partially cloudy conditions, which many of its competitors failed to do.

The significant downsides are its price and size. If it were a bit smaller or lighter, it would have ranked higher on our list. However, the Sunjack remains an exceptional option, with fast charging speeds.

Read review SunJack 25W


Real-world conditions that each panel purchased for this review was...
Real-world conditions that each panel purchased for this review was subjected to.
Photo: Jane Jackson

Why You Should Trust Us


Jane Jackson authors this review and spend 200+ days a year outside using and testing gear. For the past few years, she has spent the summer months in Yosemite and the High Sierra, working for Yosemite Search and Rescue. In other months, she travels in pursuit of perfect climbing conditions, which means lots of sun (and lots of opportunities to test portable solar chargers!). Between Yosemite and the desert Southwest, Jane is no stranger to relentlessly sunny days. When she's not living in her van, which is complete with its own solar setup, Jane is in the backcountry, using these smaller, portable panels to keep her electronics charged.

We put this comprehensive review together after researching over 80 different products on the market. After perusing several reviews, we carefully selected and bought the best of the best. Then, we tested each product objectively and thoroughly. We look at how quickly each model charges with different amounts of sunlight, how it handles multiple devices at once, the rate of charging, and its portability and durability. To test our metrics, we used each contender in the field. Our process reflects the most up to date products, with updates occurring multiple times per year.

Related: How We Tested Solar Chargers

Click to enlarge
Click to enlarge
Click to enlarge

Analysis and Test Results


Now more than ever, solar technology is growing in popularity. In this updated review, we've tested a wide variety of portable models. Our current line-up includes small panels with a 5W capacity to massive 40W panels that crank out power. By spending time testing these solar panels on the road, we get to see first hand the latest and greatest #vanlife solar setups. After looking over several options, we rated each on five important metrics. Whether you're checking out a set-up to put in your van, or a solar charger to power your iPhone while on a backpacking mission, our review offers excellent recommendations for anybody.

Related: Buying Advice for Solar Chargers

Dozens of companies produce affordable, effective monocrystalline panels ranging from small 5W models, to more substantial, powerful options that will allow for a faster charge. These monocrystalline models are much more effective and lightweight than their polycrystalline forefathers. We tested a few small wattage models that were portable and lightweight, like the Renogy 15,000mAh, which has an integrated battery pack along with a small 2W panel. We also tested the Goertek 25,000mAh, which is a similar design but with a larger capacity battery and a 5W panel. The ECEEN 13W is a larger capacity than both of these small panels, but is just as light.

The gigantic Powertraveller laid out in full desert sun.
The gigantic Powertraveller laid out in full desert sun.
Photo: Jane Jackson

Joining the ECEEN in the mid-capacity range is the BioLite 10+ and the Goal Zero 14W. Next, we filled out the upper end of the wattage range, with the addition of the Anker 21, the SunJack 25, and the Instapark Mercury 27. On the far upper end of the spectrum, we added the Powertraveller Falcon with an impressive 40-watt capacity. In general, solar technology is improving and most panels performed fairly well. That said, it's important to note that in this review, the panels' metric ratings range in scores, mostly due to their output capabilities (i.e., wattage), rather than the design of the models themselves.

Just as was the case in past reviews, panels that have large-capacity battery packs and small capacity solar panels tend to charge our electronics quickly, but take eons to charge via the sun. With this style of charger, we recommend topping off your battery pack at home before bringing it into the field.

The Voltaic is still the go-to for charging computers. However, this spring, the Powertraveller Falcon 40 joins the ranks as a large-capacity panel suited to charge laptops. The Voltaic and the Falcon impressed us with their ability to effectively charge computers. Large capacity batteries still take a good chunk of time to charge via the 20W panel, but we are excited about the improvements. We spend a great deal of time in the desert southwest, which means lots of sunshine! It's a perfect place to use solar power to keep our electronics charged.

Folded up, the panels range in size from the small Renogy or...
Folded up, the panels range in size from the small Renogy or Goertek, to the larger Sunjack or Goal Zero 14.
Photo: Jane Jackson

Value


Unlike some other products we test here at OutdoorGearLab (we've tested bikes that cost more than our cars!), portable solar chargers tend to be on the affordable end of the outdoor gear spectrum. However, even with such a reasonable price point, some models had much better value than others. For example, the reasonably priced ECEEN 13W and Goertek performed exceptionally well across the board, even standing up to some of the more expensive, higher capacity models. Other models, like the Goal Zero Nomad 14, cost a pretty penny, and did not compare to the high scorers in our side-by-side tests.


Charge Interruption Recovery


Here we consider the following questions: is your panel going to quit on you just because one cloud passes overhead, as you left it out on what appeared to be a clear afternoon? Or is the solar model strapped to your backpack, causing your phone to constantly vibrate as the connection goes in and out of the USB port? These are the questions we addressed in our charge interruption recovery metric. To test this criterion, we measured the amount each model charged within a half-hour span first in full sun, and then again in intermittent sun and shade. We also measured the output power before and after the charge interruption to see if the model could get back on track after being shaded.


The Instapark Mercury 10W working to charge a battery in prime...
The Instapark Mercury 10W working to charge a battery in prime conditions and sun orientation.
Photo: Jane Jackson

The highest performing models in this category were the ones with a large capacity (15-20W or higher) or a built-in external battery. The Renogy 15,000mAh and BioLite 10+ have built-in battery packs that can sequester energy and meter it out to plugged-in electronics, regardless of the sun quality. That said, though small battery/panel combos, like the Goertek, can manage shade — since it continues to charge your device off the battery — the panels themselves are too small to receive substantial power from the sun. The panel capacity of these models means their solar production provides a back-up as opposed to a primary power source.

Compared to the BigBlue, the Falcon has a larger surface area with...
Compared to the BigBlue, the Falcon has a larger surface area with solar cells, improving its performance in this metric.
Photo: Jane Jackson

Those with a larger surface area also tended to do better in this metric, because there are more cells exposed to the sun at one time. This is one of the major benefits of the Powertraveller Falcon 40, which has tons of surface area and a large capacity. The BigBlue 28W, which has lots of surface area as well, also comes with a built-in auto-restart function. This feature allows the panel to reconnect to your device after being shaded automatically. Naturally, the unit will still charge slower in cloudy conditions. The auto-restart feature will help to continue the flow of power in less-than-ideal charging conditions.

These are the types of conditions we wish for when charging...
These are the types of conditions we wish for when charging electronics using solar power.
Photo: Jane Jackson

Charging Speed


The main use for a portable solar panel is charging a cell phone when electricity is not readily available. We took this into account when we weighted charging speed as our highest rating testing metric. To execute this experiment, we used our lead tester's personal cell phone — a Google Pixel 3. We timed each panel as it charged our phone and also used a standard small capacity battery pack to cross-reference our results. It should be noted that in previous iterations of this test, we used an iPhone 6, which is also reflected.


To test the panels, we set each one in full sun for thirty minutes and noted how much charge the phone received. This way, we could obtain a good read on how efficiently the individual models worked over extended periods. We also timed how long it took each one to charge our 10,000 mAh portable battery packs, so we had that data to compare as well. In general, this size battery can charge an iPhone from 0 to 100% about two times.

The X-Dragon 20W panel has multiple loops to hang it up oriented...
The X-Dragon 20W panel has multiple loops to hang it up oriented toward the sun. However, we found that it worked well propped up on the ground instead, especially since it is such a sturdy panel and can hold itself up easily. This model also had the fastest charging speed out of any in our fleet.
Photo: Jane Jackson

We found a broad range in the ability to charge batteries, from literally not charging the battery pack at all, like the Goal Zero Nomad 14W, to charging it up a whopping 17% in 30 minutes, like the ECEEN. This considerable variability is due to the extensive range in output power of the contenders we tested. Twenty-one watts is four times as powerful as a 5W device, so it makes sense that panels like the BigBlue earned one of the highest in our testing. The ECEEN held its own among the 15W and the 20W models.

Using this USB multimeter, we found that the measured output was...
Using this USB multimeter, we found that the measured output was often less than what the manufacturers' claimed.
Photo: Jane Jackson

A priority of solar chargers is to provide a fast charge. Therefore, we recommend investing in a higher wattage charger to facilitate this function. For speed and efficiency, a more effective watt option is more efficient. That is unless you're trying to save weight or money, in which case a less powerful model might be a good compromise. With that in mind, it's no surprise that some of our highest scoring panels in this metric were panels with the largest capacity.

Multiple Device Charging Speed


As you might guess, when tasked with the challenge of charging multiple devices at once, the more powerful models performed better than lower wattage models. Smaller panels such as the 5W and 7W models don't have the power to sustain two gadgets at once. If this is a priority for you, then select a panel with a higher wattage. Generally, our testing found lower watt models to be less capable in this metric than the higher watt devices that can charge two devices.


The Big Blue, Anker 21, and SunJack were high scorers, as was the Goertek 25,000mAh. As discussed above, the results show that models with higher wattage are more effective at charging multiple devices at once. We were impressed by the SunJack's overall power and efficiency in this metric. Panels with built-in battery packs also excel in this metric, with the Goertek holding its own.

Shown here are the three ports on the updated version of the...
Shown here are the three ports on the updated version of the BigBlue. We usually didn't use all three at once - since it reduced the effectiveness of the panel, but we used the USB-C port often.
Photo: Jane Jackson

Durability


By design, portable solar panels need to be able to withstand long exposure to the elements. The way to get ample charge to small electronics is by leaving the panels exposed to the sun for long periods of time. To make sure these panels are up to the task, we have tested them in all kinds of conditions — from baking desert sun to high alpine terrain to extreme wind and rain. In general, almost all the panels stood up to the challenge. The canvas protective fabric is like an exoskeleton-guarding the important insides of the panels. Solar technology seems to be advancing too, with companies working to make cells more durable and resistant to sun and water damage.


When scanning through reviews online, we noticed complaints about various models withering and warping in the sun. Because of this, we were extra vigilant, even when we set them out in the blazing southern Utah desert sun. In our testing period, none of the chargers endured much damage. These are robust machines, and with technology advancing every year, solar panel companies have come leaps and bounds in the construction of portable options.

There is a fine line between exposure and turning your panel into a...
There is a fine line between exposure and turning your panel into a frying pan. Be aware that some panels will warp if left out in very hot conditions.
Photo: Jane Jackson

We appreciated the external storage options on the Anker 21W and the ECEEN. These pockets not only protect extra gadgets, but also keep the USB ports protected. Some of the models, like the Goal Zero Nomad 14W, have a mesh pocket, which looks nice and is convenient but is so tightly attached to the panel itself that it started to wear out. The BioLite 10+ is incredibly durable in its construction.

These panels lack canvas covers but instead are made from solid...
These panels lack canvas covers but instead are made from solid plastic that improves their overall durability.
Photo: Jane Jackson

Weight and Portability


Since an importany function of many of these panels is to remain portable, this is a crucial category. A model that is too heavy or bulky will be left behind to collect dust in the closet when you set out on your next adventure.


The panels that swept this metric by boasting the lightest weights were the Renogy 15,000mAh and the ECEEN 13W. The Renogy weighs 9.5 ounces, while the ECEEN panel weighs in at 12 ounces on the dot. These are the two standout models; most panels weigh in between 18 and 25 ounces. Though the ECEEN is an award winner, we like to say that it is a fairly simple panel, with its basic folding design cutting down on weight.

Compared to the Anker 21W, the Renogy is pocket sized. Its charging...
Compared to the Anker 21W, the Renogy is pocket sized. Its charging capabilities are much less than the Anker 21W, however.
Photo: Jane Jackson

Others come with lots of accessories and extra features, which make them more exciting to use, but also make them bulky and unappealing to carry on long trips. There is a happy medium between overkill and overly simple, which of course depends on your preference and needs.

The Falcon is definitely the largest panel we&#039;ve used in a while.
The Falcon is definitely the largest panel we've used in a while.
Photo: Jane Jackson

While portability is a critical consideration, we placed more emphasis on performance. If the panel doesn't work, then it is just training weight. That was our reasoning behind handing out awards to larger panels like the BigBlue 28W.

Here&#039;s the tiny Renogy panel in comparison to a standard Climbing...
Here's the tiny Renogy panel in comparison to a standard Climbing magazine. They are about the same thickness, but the Renogy has a much smaller footprint.
Photo: Jane Jackson

Accessories


To standardize our testing and procedures, we used the same 10,000 mAh battery pack and USB cord when testing all models. The battery we used is a well-reviewed and inexpensive pack designed to charge small gadgets and phones.

Accessories can quickly add up to create a heavy, cumbersome set up...
Accessories can quickly add up to create a heavy, cumbersome set up. These small external batteries work great to keep your electronics charged without creating a junkshow on the panel.
Photo: Jane Jackson

Panels that don't come with a built-in battery are often paired with a portable external battery pack. This arrangement allows the panel to charge the battery during the day while you're using your devices, and you can charge your device at night via the external battery. External batteries are an essential addition to any portable charging kit. Most modern tablets and smartphones demand higher power (like 2A charging ports) and this becomes harder to produce from the sun (which is variable at best). Instead of bulking up the solar panels themselves and making them too cumbersome to actually use, we found it much more effective to simply charge external batteries on a rotating system to keep a constant stockpile of fully charged battery packs ready to go. That way, you have a less strong and, most importantly, lighter weight, solar charger that charges a high-quality external battery. This battery can, in turn, produce the necessary 2A of current to charge small devices.

Some of our testing fleet catching rays under the watchful eye of...
Some of our testing fleet catching rays under the watchful eye of Castleton Tower in Southern Utah.
Photo: Jane Jackson

Conclusion


Deciding on the right solar charger can be an overwhelming task. To make it easier to wrap your head around, you'll want to figure out what you will be using it for, and go from there. Are you running a mobile office and need to keep multiple, energy-hungry devices happy? Or are you concerned with having a fully charged phone on a weekend excursion?

The smaller watt options are going to be less expensive, and often less powerful. As you increase the wattage, the panels typically become more efficient. The sky is the limit, but it depends on how much money you are willing to spend. We narrowed in on the top competitors and put them to the test. Some perform better than others, and a higher price tag doesn't necessarily mean a better product. We hope that our thorough tests and reviews of these products will be useful to you as you shop around for your new solar charger.

Jane Jackson