Solar powered flashlights...any good ones out there?

What can you recommend for solar flashlights?

Thanks

You would be better off getting an flashlight that has an micro usb charging socket and get a solar panel to charge it, or even an usb power bank with a solar panel built in.

John.

the WakaWaka Power-- I'm not disappointed in mine.

- LetThereBeLight!

Unless you have two of them you are probably better off with a solar cell and charger and several cells to rotate in the light and charger so when one cell is used up you aren't stuck in the dark waiting for the sun to come out and charge a battery and when there is enough sun outside you no longer need the light at that moment.

OK, thanks.

Are there any usb flashlights and solar panels you recommend?

I'd like to try both flashlights and the panel options. The nice thing about a dedicated solar light is simplicity.

slackercruster said:

OK, thanks.

Are there any usb flashlights and solar panels you recommend?

I'd like to try both flashlights and the panel options. The nice thing about a dedicated solar light is simplicity.

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They may be simpler but typically most solar flashlights way underperform as it takes a pretty good sized solar cell to charge a decent sized battery to be able to power a light to decent output and runtime levels.
I don't really have a lot of experience with USB charging flashlights or solar panel setups but you can search for threads talking about both those topics there is a LOT of information available. The USB charged flashlight would be better than a solar powered one in that you can charge it multiple ways besides solar there is home wall USB adapters, laptop and computer ports, car USB chargers, solar panel USB power solutions, and even USB power banks.
A lot of people get enamored about solar but don't do their homework about it. In my state we have lots of cloudy days in the spring and fall/winter which could reduce solar charging usability greatly at times sometimes overcast for days. Also solar cells don't work at night either. Personally I think solar charging is an option but unless someone is far from the grid, and has no other charging methods available for long periods of time it is best to have the option of charging from other power sources too.

As far as solar panel goes, 20 - 60 Watts solar panels are your best bet, and don't forget to buy 10 - 30 Amps hour Lithium-ion battery bank too as it will save you unnecessary heartaches when it's somewhat cloudy out there. And I kind of have to agree that solar flashlight's useless. Why? 50mA output even at 12 Volts from the body-mounted solar cell won't be enough for the Lithium-ion battery charger, even with the buck DC-DC converter which is quite efficient.

As for the solar setup options, I bought Anker 21 Watts USB solar panel and Powercore 26800 (non Qualcomm QuickCharge version - that way I can use two input USB ports on the battery bank to charge the 27 Amps hour battery bank as quickly as I can at 3 Amps current rating) for the purpose of having the juice when I am camping (I will be doing astrophotography so I need to be able to charge the batteries for my Nikon D3400 DSLR camera). I just use the biggest 18650 Lithium-ion cell I can buy (like LG INR18650MJ1) and use my DIY Nichia 319AT flashlight that way, as well. It'd have much longer runtime than the useless solar flashlight, to be frank - in other word, don't bother buying the solar flashlight.

Sometime, maybe 2003, I used a solarflashlight. After a couple times charging on a south glass window ledge inside, the plastic frame of the light warped. little panel on it was still functional but the anemic incandescent bulb was near useless for tasks. Live and learn.

Simplicity? Have you tried the wind up lights?

A 5 watt solar panel can be had for not that much money, and will charge an 18650 in full sun. Don't go fully draining your battery, or that will take a while. Nitecore F1 is a solid candidate for a simple charger. Hopefully they will update that model with a stronger slide spring. If you are car camping, or otherwise stationary, a two bay charger is feasible and more flexible (MiBOXER C2-3000 being one choice if available- disclosure: MiBOXER sent me one of them for review)

+1 to what Dr. Mario said.

For maximum skimp, you could go with a 14W Anker or Aukey solar panel ($40), Nitecore F1 charger/battery bank ($10), and the 18650 based light or lantern of your choice with a couple batteries.

The 14W can put out 1-2A quite fine, so a few hours of open sunshine can fully recharge a battery. It is 2 panel instead of 3 like the better but bigger 21W.

But there's a reason why those panels are something like 10 inches by 14 inches or more.. it takes that much solar panel to get useful juice.

Anything with a 2 inch by 2 inch panel will never get enough power into it... so either it has super low output to conserve the little juice it can store, or it simply can never do a real recharge from solar (only say minor top offs).

KITROBASKIN said:

Sometime, maybe 2003, I used a solarflashlight. After a couple times charging on a south glass window ledge inside, the plastic frame of the light warped. little panel on it was still functional but the anemic incandescent bulb was near useless for tasks. Live and learn.

Simplicity? Have you tried the wind up lights?

A 5 watt solar panel can be had for not that much money, and will charge an 18650 in full sun. Don't go fully draining your battery, or that will take a while. Nitecore F1 is a solid candidate for a simple charger. Hopefully they will update that model with a stronger slide spring. If you are car camping, or otherwise stationary, a two bay charger is feasible and more flexible (MiBOXER C2-3000 being one choice if available- disclosure: MiBOXER sent me one of them for review)

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The only solar flashlights I've ever seen have 5mm LEDs and 5mms LEDs don't take a lot of power unless you run a bunch of them. As for windup lights with the efficiency of LEDs now is such that with lower modes and an 18650 battery you don't need to use them and if you tried to recharge an 18650 with a hand crank you would have to have a carpal tunnel operation afterwards.

The wind up flashlight I was thinking about is the 4 emitter self-contained with handle. Cheap, but how durable?

Here is a brief (54 seconds) video showing a ~5 Watt Sunkingdom solar panel using the MiBOXER 2 bay charger with a pair of 18650's starting at something like 74%. Took about 3 hours to charge, seems like, in full sun. MiBOXER shows .45A and .5A for the two bays. The solar panel is about the size of a license plate and maybe 3mm thick plastic, not counting the USB connection/charge controller. My 15 Watt solar panel has more power (in full sun) than I can take advantage of with the solar compatible chargers at hand. Clouds take so much away from solar charging, at least with the panels used by me. Charge when the sun is shiny, if you can.

https://photos.google.com/share/AF1...?key=T3RadFlnTm9RMEl2VlZVVURmd0RYUWY4OXhTRlln

What would be more useful is true output (watts) specs on these solar flashlights and also crank flashlights.

Your solar cell (5W sounds about right on output 0.95A charging around 4v or so with losses due to electronics and heat it would certainly depend on the actual mah of the cells being charged. I'm not sure how big a 5W cell is these days but I'm guessing that a solar type flashlight the size of the old large 6v lanterns may possibly have enough surface area to start to put a charge on an 18650.

Since we are at about 7000 feet in altitude in what is considered a semi-arid environment, we get good sun. Curiously, more watts can be achieved when there are substantial white clouds in the sky, with the sun not obstructed by a cloud. This will exceed stated ratings sometimes.

KITROBASKIN said:

Since we are at about 7000 feet in altitude in what is considered a semi-arid environment, we get good sun. Curiously, more watts can be achieved when there are substantial white clouds in the sky, with the sun not obstructed by a cloud. This will exceed stated ratings sometimes.

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That makes some sense..... as that high up light reflected off of clouds is probably a lot brighter than down nearer to sea level.

I'd agree with the other comments and think the best solution is buying a good USB rechargeable flashlight and then using a 20 watt or higher folding USB solar charger to provide the power to recharge it.

I like my Fenix RC11 USB Rechargeable flashlight that has a magnetic USB charging connection mechanism and it will charge fine directly connected to my Aukey 20 folding solar panel with Sunpower cells. However, I actually prefer to use a USB powerbank in between the solar panel and USB charged Fenix light because the powerbank I have has a power passthrough feature that will let the power from the solar panel charge the flashlight up directly when there's sun but if it gets too cloudy for the panel to produce the needed USB power the powerbank kicks over and draws power from it's own batteries to recharge the flashlight without much of an interruption. The other great thing about it is if the solar panel produces more power than it takes to charge the flashlight the extra power will go into recharging the powerbank keeping it full as well as the flashlight which can be used for other USB devices.

As for an actual solar powered flashlight most units I've tested simply don't pass the muster of long term viability. They all seem to die rather quickly from what I'm guessing is heat related cooking of the battery. Most solar lights are really designed with inadequate venting or heat dissipation so they become an oven inside them and the electronics and battery are subjected to more heat than they can handle to maintain the health and longevity of the battery and components so they fail after only a number of months of constant use. The solar cells mounted on these solar flashlights are generally too small to provide an adequate power source to fully recharge the battery inside the light even after multiple days in the sun.

The Goal Zero Torch 250 however, has done rather well even with these known limitations as a all-in-one solar flashlight and lantern plus it has a decent handcrank dynamo for emergency use when the sun isn't shining. The solar panel on it is bigger than most solar lights (though still not big enough) but I will plug it into my USB folding solar panel to charge it up faster and it also serves to protect the battery from heat by placing the Torch behind the solar panel. If I need it charged a little faster I can set it in the sun in addition to being connected to the folding solar panel so it can utilize it's own panel in addition to the larger one.

A Goal Zero response to an Amazon customer that really addresses the nature of a product such as this:


We appreciate your feedback! It is always a struggle to find the right balance between available solar, and the battery capacity one of our products has.

There are two things we can do, as a manufacturer, to decrease charge times from solar. One, we can increase the size of the solar area. The second is to reduce battery capacity.

In this product, we felt that reducing the battery capacity down from 4400 mAh was not an option, as it is intended to be a USB power station and should be able to at least recharge the majority of the USB powered devices on the market today. Battery capacity less than what is available on the Torch 250, would eliminate the ability to recharge thousands of USB devices.

We did increase the available solar area, and felt that increasing it even more was pushing the limits as it relates to the size of the product. A great feature of the GOAL ZERO ecosystem of products, is that they are designed to work one with another. One could recharge the Torch 250, directly from solar, at a much faster pace by connecting it to one of our stand-alone solar panels, like a Nomad 7 v2.

We apologize that you feel we did not advertise the solar aspect of this product properly. As we reviewed the description, we did take note that we actually under promised on the solar by suggesting it is a "trickle charge" for its internal battery. It does more than trickle charge the internal battery, but again, it is not intended to recharge the internal battery at a rapid enough pace to recharge the internal battery in a day, by itself.

One of the features that differentiates this product from others is the ability to recharge it a variety of different ways, depending on the user's use case. One could recharge it from a USB wall outlet, USB car charger, built-in crank, and/or built in solar. How fast it recharges, depends on how the user is recharging it. The USB wall outlet or Car Charger is the fastest, as the available power is maximized in those two scenarios. In the right conditions, with the right solar panel, the Torch 250 could be recharged as fast as it would be recharged from the wall or car outlet.

The last thing to clarify would be that optimal solar charging, with any solar product, is achieved in direct sunlight. Any obstacle, including a window, will reduce the solar efficiency significantly. Modern windows have UV protection that blocks the valuable UV rays needed to solar charge/recharge. We would recommend that this be considered while using any of our solar products, or the solar products manufactured by other companies. We will ensure that our Solutions Center is also informing customers in similar situations about the optimal solar recharging scenario. We apologize that this was not clarified to you when you called in.

We hope this provides you and others reading this review some clarity to the "why" behind the product and some understanding of what factors need to be considered while recharging from solar.

Goal Zero's response above in Kitrobaskin's post proves that solar flashlight is actually useless, not to mention they point out that solar panel size is actually a function of how much current they pump out (milliamps to amps depending on size of arrays and how they're wired up). Hence you're actually better off buying USB rechargeable flashlight or an 18650 Li-ion flashlight and charger along with the larger solar panels (common sizes ranging from 7 to 28 Watts and beyond - I recommend that you buy a solar panel with Sunpower Maxeon solar cells which several USB solar panels use as they're quite efficient in bright sunlight, and I know Anker 21 Watts solar panel do use such solar panels).

Long story short; be careful of what you expect in such products. Not all hardware perform the way they're intended to.

Check out Suntactic's 14-watt solar panel to which you can connect something like an Xtar Charger to recharge your lithium ion batteries. The solar powered flashlights I've seen never were bright enough for me. The aforementioned WakaWaka Power is not exactly a "flash"light per se, but it does emit high and other lumens while possessing the ability to charge your cell phone and can be recharged in/by the sun. If the crap ever did hit the fan it would be the WakaWaka Power I'd use to recharge numerous Nitecore Tubes and a few Tips as a means to postpone depletion of my primaries.

- LetThereBeLight!