The 10 Best Portable Solar Generators
Editor's Notes
December 17, 2020:
Unsurprisingly, given the current trajectory of solar-power technologies, it was a very busy round of updates. A combination of availability issues, poor consumer feedback and new-and-improved models led us to all but rebuild this list from scratch, with our only remaining selection being the Renogy Phoenix.
If you aren’t particularly electrically inclined, this can be a bit of a confusing category to shop in. If that’s the case, we likely don’t have enough space here to provide you with the answers to all of your questions, but we can give you a few tips.
Here’s three important things to keep an eye on while you assess your options:
Solar Panels: Not all models come with one. In fact, it seems that many top companies sell their panels separately, affording their customers the flexibility of being able to decide just how much panel (or how many, for that matter) they need. Without a companion panel, your solar generator will essentially act as a basic (though, albeit, sometimes very large) external battery pack. You can use their adapters to charge them up with a standard 120-volt receptacle or your 12-volt car outlet, but when they run out of juice, you’ll be out of luck — until you can find your way back to a power source.
Models we ranked that come with, or have an option to come with, a solar panel include the Wawui Travel, Jackery Explorer 500, Jackery Explorer 1000 and Goal Zero Yeti 400. If you're considering a model that doesn't come standard with hardware, then you might be interested in checking out our list of Best 100-Watt Solar Panels.
Capacity: The vast majority of the time, battery capacities in this category are expressed in watt-hours. Efficiency ratings can complicate this calculation, but for the sake of keeping things basic: a watt-hour denotes, quite simply, that a battery can put out a watt for an hour.
So, for example…
a fully charged 1,000-watt-hour battery can provide 1,000 watts to a single load for one hour;
a fully charged 1,000-watt-hour battery can provide 500 watts to two loads for one hour;
a fully charged 1,000-watt-hour battery can provide 500 watts to a single load for two hours;
and so on.
In this respect, models we ranked varied drastically. Units with larger capacities will very typically have bigger dimensions and larger unit weights, not to mention heftier price tags, so you’ll likely want to select a unit that balances portability and affordability with a capacity equal to or greater than your needs. At 84 watt-hours the Wawui Travel has the lowest capacity of any model we ranked, while the Goal Zero Yeti 3000X has the largest, at 2,982 watt-hours.
Output: Regardless of what their rated watt-hour capacity is, each of these machines will have a separate maximum power output that's rated in watts. While a unit's rated capacity will determine how long it can keep a load running for, its rated output determines which loads it can accommodate without causing an overload or overcurrent fault.
For example, The 120-volt AC outlet on the Jackery Explorer 160 has a 100-watt maximum output, which restricts it to things like charging laptops or powering small lamps. By contrast, the three 120-volt AC outlets on the Jackery Explorer 1000 have a 1,000-watt maximum output, which makes it possible for them to supply more demanding loads, like an electric grill or pressure cooker.
If you have a good idea what loads you're hoping to supply with this generator, it's a good idea to check what their rated watt demands are, and make sure that they're equal to or lesser than the generator in question's maximum output rating.
June 14, 2019:
A solar generator usually consists of two main components: A panel and a portable power generator. The panel converts sunlight into electricity, and the generator is made up of an inverter and a battery. The inverter converts DC power from the panel into AC power, which is what’s used in the vast majority of homes today. The battery stores any energy that’s not currently being used – ensuring you’ll have use of your electronics and maybe some light appliances in the event of a power outage.
There are many solar generators on the market today, and they couldn’t vary more as far as features and price. You’ll surely pay for reliability and convenience, and whether you’re willing and able to make such a significant investment is no small question. Our selection here covers a full range of models, to help take some of the guesswork out of your search process.
Speaking of investments, joining the list is the Renogy Lycan Powerbox, which boasts a large watt-hour capacity and can therefore power many devices, both small and not-so-small, at once. These include things like toasters, hair dryers, and even CPAP machines. It features four USB outlets and four DC ports, as well as a handy LCD screen that provides a battery status reading. Solar panels can be daisy-chained and plugged into it, for charging. At 60 pounds, it’s on the heavy side, but you’ll appreciate the two wheels and suitcase-style handle for easy pulling. Note that you’ll have to purchase your panel(s) separately, as none come with it. On the bright side, you can carefully select the shapes and sizes of panels that are right for you. (And Renogy makes some top-of-the-line ones.)
Another newly added item is the Goal Zero Yeti 400, which also features a convenient light-up screen with the status and a countdown in hours until it will no longer have charge. Price-wise, it’s pretty middle-of-the-road, so it’s great for the more budget-minded shopper who wants a reliable selection that can handle small-to-medium devices during camping, power outages, etc. It conveniently can be charged through either an AC outlet or a solar panel. It’s relatively lightweight at 16 pounds, and it’s around the size of a lunchbox.
Both of these new additions are backed by 12-month warranties and do not come with panels. No matter which you go with, always follow the included instructions carefully to ensure you're using them in a safe, proper way.
How Solar Panels Work
Silicon by itself is not a good conductor of electricity, but with the addition of certain impurities, a process known as doping, it becomes highly conductive.
All solar panels make use of photovoltaic cells. The inspiration for creating photovoltaic cells came about in 1839 when Edmond Bacquerel, a French scientist, noticed that certain materials created sparks when exposed to sunlight. By the late 1800s, researchers realized they could harness this release of electricity, which they termed the photoelectric effect, and created the first photovoltaic cells out of selenium.
Photovoltaic cells are comprised of two layers of semiconducter material, most commonly crystallized silicon. Silicon by itself is not a good conductor of electricity, but with the addition of certain impurities, a process known as doping, it becomes highly conductive. The lower layer of a photovoltaic cell is usually doped with boron, while the upper layer is usually doped with phosphorous. Boron facilitates a positive charge in silicone, while phosphorous facilitates a negative charge. Negatively charged silicon has a lot of extra electrons that are not bonded with neighboring atoms. Positively charged silicon has the opposite property. It has a lot of extra atoms that have no electrons to bond with.
When light strikes a photovoltaic cell, it is absorbed by the semiconductors causing them to release electrons. If the P-type and N-type semiconductors are placed next to each other, all of the free electrons released from the the negatively charged layer rush to bond with the free atoms in the positively charged layer. Not all of the electrons will find atoms to bond with, however. This mad rush of electrons also produces an electric field at the P-N junction (the area where the two semiconductors meet).
This electric field allows electrons to flow from the P-type semiconductor to the N-type, but not in the other direction. Once an equilibrium is reached in the N-type semiconductor, the extra electrons have nowhere left to go since they are blocked by the electric field from going back to the P-type semiconductor. By attaching an external circuit, a new pathway is created for electrons to flow from the negative layer to the positive layer. This flow of electrons passing through the circuit produces an electric charge that can be used to power other devices.
Benefits Of A Portable Solar Generator
Being left in the dark with no power is not a situation that anybody hopes to find themselves in when camping or dealing with an emergency. Unfortunately, for many owners of traditional generators, this is a situation that can happen all too often. You may forget to bring along an extra tank of gas or keep some stored in the shed. Even if you do happen to have remembered to keep a tank of gas lying about, most people don't realize that it only takes three to six months for gas to go bad, so not only do you have to remember to keep gas on hand, you also have to remember to change it out every couple of months.
You may forget to bring along an extra tank of gas or keep some stored in the shed.
Unlike with traditional generators, with a solar generator there is no need to worry about keeping gas lying around. Solar generators are self-sustaining and can always produce new power, as long as the sun is shining. They also contain a battery to store the excess energy generated during the day, which can then be used to power your devices throughout the night.
Solar generators are ideal for camping situations as they are completely silent. Since they make use of semiconductors and electric fields to produce electricity, they don't have any moving parts. This makes them more durable and reliable than their mechanical counterparts.Traditional generators make use of a motor to rotate the components of an alternator, thereby creating an electric field. The motors used to power traditional generators are often quite loud. Some of the quietest models still produce at least 53dB of noise, which is roughly equal to the sound of light traffic passing by you on a street, with most models producing closer to 75dB, which is roughly equal to the noise of a vacuum cleaner. Not only is a traditional generator loud and and annoying if set up near your campsite, you won't be doing your neighbors any favors either.
Finally, probably one of the biggest benefits of solar generators is that they are eco-friendly. Unlike traditional models, they neither consume fossil fuel nor release noxious gasses, like carbon monoxide, into the air. This means you can use one anywhere that is exposed to sunlight, such as in a greenhouse, without having to worry about poisoning yourself or the environment.
Three Things To Consider When Choosing A Portable Solar Generator
Before clicking that buy button on that solar generator you've had your eye on, you should stop and ask yourself a few questions to ensure it meets your needs. While a host of other features may play into your decision, the three most important determining factors should be input, output, and storage.
On the other hand, if you want it to function as a power backup for your home refrigerator, you will obviously need a much stronger unit.
First, ask yourself what kind of input works best for you. Some solar generators have their panels mounted directly onto the unit or built-in to it, while others are connected to the panel by a cable. Panels that are connected by a cable will offer you more placement options, as both the panel and the generator don't need to be set in the same spot. The longer the cable, the more versatile. There are also models available with panels that fold up for easier transport, like those commonly used in small solar chargers.
Next, ask yourself how much power you need. What are the wattage and voltage requirements of the devices you plan on charging with it? Some models may produce as little as 50 watts, while others are capable of outputting well over 1,000 watts. If you just plan on using your solar generator to power your laptop and speakers while camping, a small model will often suffice. On the other hand, if you want it to function as a power backup for your home refrigerator, you will obviously need a much stronger unit.
The final concern regards power storage, or battery size. The larger the battery, the more energy a model can store for overnight use. As with the rest of the features, though, you'll have to find the model that best balances your portability and power needs.