Need a hand choosing the best solar charger? After spending 9 years testing 58+ models, we know a thing or two about the contenders that offer up the highest performance. We've purchased 14 for our 2020 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.
The Best Portable Solar Panels and Chargers of 2020
Best Overall Solar Charger
We love efficient solar chargers that give us the most output. That's why the BigBlue 28W receives our highest accolades once again. It features over 28-watts of power that'll charge small electronics fast and efficiently. With a built-in ammeter, you can track its output while it charges. Its simple design and the reasonable price tag is another reason we love this product so much. Its newest iteration features a USB-C port, meaning it can charge most Mac laptops. We appreciate this awesome new feature.
Unfortunately, as the name suggests, this panel is a bit bulky, weighing in at 23.5 ounces. As a result, it's better suited for frontcountry use. Aside from that, we can't think of anything else we don't like.
Read review: BigBlue 28W
Best Bang for the Buck
Our latest winner of the Best Buy Award goes to the ECEEN 13W. This panel is simple and sleek and is the no-frills option for quick and easy charging in the backcountry. If you need a lightweight and portable panel that can be used anywhere and charge small gadgets quickly, the ECEEN is the panel for you. We were very impressed when we first plugged it into our external battery pack and watched as it charged almost as fast as panels that are double its size. All of this functionality is great, but when paired with a reasonable price tag, it was a no brainer!
The downside to this panel is its simplicity. Though we liked this design for portability, it fell short when it came to charging multiple devices at once and when trying to use the panel in marginal conditions. Thirteen watts is still a relatively small-sized panel, so for charging larger electronics or power-hungry gadgets, the ECEEN might not be the best choice.
Read review: ECEEN 13W
Best for Durable Performance
BioLite SolarPanel 10+
The two proceeding award winners are more focused on performance than design. We wanted to highlight the BioLite 10+ for its durability and portability. Its rugged construction makes it incredibly reliable, as does its built-in battery pack. The battery regulates charge, so the panel works fairly well in sub-optimal charging conditions. We liked the kick-stand and fold-out design, as it's sleek and portable enough to fit into our backpacks on most 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 this could certainly be a hold-up for some. There are plenty of less-durable panels out there that will perform as well as the BioLite, but few can stand up to this panel in terms of overall design and construction.
Read review: BioLite 10+
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. Between Yosemite and the desert Southwest, Jane spends ample time in the sun, making her a solar-charging expert. When she's not living in her van, which is complete with its own solar set-up, Jane is in the backcountry, using these smaller, portable panels to keep her electronics charged.
This comprehensive review was put together after researching over 60 different products on the market. After perusing several user reviews, we carefully selected and bought the best of the best. Then, we put in the time to test each product objectively and thoroughly. We look at how quickly it charges with different amounts of sunlight, how it handles multiple devices at once, the rate of charging, and its portability and durability. To test this, we used each in the field while in the OutdoorGearLab lab! Our process reflects the most up to date products, with updates occurring at least four times per year!
Related: How We Tested Solar Chargers
Analysis and Test Results
Now more than ever, solar technology is growing in popularity. In this updated review, we have well-tested options representing a full spectrum of portable models. We include small to large options that range from 5W to 40W. Spending time in Yosemite Valley, this test period meant that we got to check out the latest in #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 great recommendations for anybody.
Related: Buying Advice for Solar Chargers
Now, dozens of companies produce affordable, effective monocrystalline panels ranging from small 5W models to more substantial and more powerful 20W options 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 Hiluckey Portable Power Bank, 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.
Joining the ECEEN in the mid-capacity range is the BioLite 10+ and the Goal Zero 14W. We also kept the RavPower 16W and the SOKOOO 22W in the mix from previous seasons of testing. Next, we filled out the upper end of the wattage range, adding the updated BigBlue 28 and keeping both the PowerGreen 21W and the Voltaic 21W. Solar technology is improving as a whole; while each panel performed well, their 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. We often opted to top off the battery packs from a wall charger before bringing them out on trips.
Joining the two solar setups that are designed to charge laptop computers (the Voltaic Arc 20 and the X-Dragon 40W) is the BigBlue 28W which now comes with a USB-C port, making it easier to connect a newer Mac computer directly into the panel. The Voltaic and the new design impressed us with its larger capacity and ability to charge Mac computers with ease. The large capacity battery still takes a good chunk of time to charge via the 20W panel, but we are excited about the improvements.
Unlike some other products we test here at OutdoorGearLab (we've tested bikes that cost more than our cars!), portable solar chargers all tend to be on the affordable end of the spectrum. However, even with such a reasonable price point, some models had much better value than others. For example, our Best Buy winner, the ECEEN 13W, performed quite well across the board, even standing up to some of the more expensive, higher capacity models. Other models, like the Goal Zero Nomad 14, costs a pretty penny but did not compare in our side-by-side tests.
Charge Interruption Recovery
Is your panel going to quit on you just because one little 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 these models, we measured the amount each one 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 highest performing models in this category were the ones with greater wattage 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 Renogy and the Hiluckey Portable Power Bank, can manage shade since they will continue to charge your device off the battery, the panels themselves are too small to receive substantial power from the sun. This means their solar function is more of a back-up than a primary power source.
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, which is a benefit of X Dragon 40W, 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. Though the unit will still charge slower in cloudy conditions, this feature will help continue the flow of power in less-than-ideal charging conditions.
The majority of the time, these solar panels are being used to charge cell phones when electricity is not available. Because this is typically the case, our highest rating metric in testing is Charging Speed. We wanted to know long it took each model to charge an iPhone 6 (the main phone used for testing, though we've also added in a Google Pixel 3) as well as our small external battery packs. We set each one out in the direct sun for 30 minutes and measured how much the phone charged.
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.
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. In this metric, the BigBlue outperformed all but the XDragon by charging our external battery pack the fastest. The ECEEN held its own among the 15W and the 20W models.
Overall, it's a better idea to invest in a contender with a higher wattage since a fast charge is what we look for in a solar panel first and foremost. For speed and efficiency, a more significant 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 the less powerful ones. The 5W and 7W models don't have the power to sustain two gadgets at once, which might not be what you're looking for anyway. That's why the lower watt models get a lower score compared to the models that can charge two devices.
The Big Blue, Renogy 15,000mAh, and Hiluckey were high scorers, followed by the X Dragon. Some panels, like the Wildtek Source 21W, now have three USB ports, but we found this panel to have the same issues as many of the 2-port versions out there. It appears that models with higher wattage are more effective at charging multiple devices at once. Panels with built-in battery packs also excel in this metric, with the Hiluckey holding its own.
Since their job is to lie out exposed to the elements, we had high hopes when it came to their ability to hang tough as we took them through deserts, mountains, sun, wind, and rain. Through months of testing, nearly all the contenders 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 customer 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.
Models with external storage pockets, like the Powergreen 20W and the ECEEN, won us over because their pocket not only protects extra gadgets but also keeps the USB port dry and covered when charging. Some of the models, like the Goal Zero Nomad 14W, had a mesh pocket, which helps to see what is inside, but was so tightly attached to the panel itself that it started to wear out. The BioLite 10+ is incredibly durable in its construction. We'd like to think the coated panels could be mounted to the roof of your van and last for a good while.
Weight and Portability
Since the primary function of all these portable models is to be, well mobile, this is a relevant 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 highest-ranking panels in terms of weight this time around are 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. From there, most of the panels average between 18 and 25 ounces. Though the ECEEN is an award winner, we like to say that it is a fairly boring panel, with its basic folding design cutting down on weight.
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. Though portability is vital, we found that we focused more on performance in our testing, since the panel is just dead weight if it doesn't work at all. That was our reasoning behind handing out awards to larger panels like the BigBlue 28W and the PowerGreen 21W.
To make the review more standardized across the board and to simplify the testing, we used a standard battery pack and USB for all the panels. We used a 10,000 mAh Portable Charger, as it was an inexpensive external battery with good reviews, used mainly for charging phones and small gadgets.
Many people choose to combine a solar charger that doesn't have an internal battery with an external battery. This arrangement allows the panel to charge the battery during the day while you're using your devices (phone, GPS unit, and the like), and you can charge your device at night via the external battery. External batteries are an essential addition; as our tablets and smartphones demand higher power (like 2A charging ports), this becomes harder to produce from the sun (which is variable at best), and requires higher wattages, and thus more panels, meaning more weight and bulk. The best option, in our opinion, is to have a less strong (and lighter weight!) solar charger that charges a high-quality external battery, which can, in turn, produce the necessary 2A of current for our devices.
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 become more and 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