Solar Charing not popular with CPF?

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mega_lumens

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Aside a few threads on solar charging, I'm not seeing threads on this topic. Why isn't solar charging popular on here especially for emergency/prepping? I don't know much about solar charging but I'd like to learn what brands, models and tech is to rave for in 2014? I want one system that can charge 18650s or Eneloops or radios that run on either lithium or NiMh. Are we there yet where solar chargers can handle 18650s size lithium? With the best setup, how many hours of charging are we talking about and how many 18650 or eneloops can solar chargers handle at once with today's tech?
 

Lynx_Arc

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I think it is mainly the cost vs other methods of emergency power available. As much as I like the idea of solar charging it has one issue that cannot be denied in that if you don't have any decent sun out (raining or really cloudy) then it is not very useful and in some places you can get rain for days upon days at times. Most places have access to automobiles such that car charging only requires some gas and proper chargers and car cords which is typically a lot cheaper to aquire than a solar setup which in the end probably have to rely on chargers similar to or perhaps exactly the same as car chargers. If you are on the coast in hurricane alley then you could have an emergency that solar charging would perhaps be the best last thing but far from the coast the only things that can get you is floods tornadoes and earthquakes and with the exception of floods and a massive tornado there should be plenty of cars out there to plug into. Many solar setups use lead acid batteries to store power for later charging and to buffer and a car does the same but with a battery that is huge in comparison and a charger that runs off gas that can charge it up in minutes compared to the power it could take half a day to put in a small lead acid battery.
 

Illum

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Solar charging is not realistic unless the application is static, and that power use is sporadic, not cyclical. Power derived from solar is finicky and requires regulation for it to be useful. This increases upfront cost and not immediately compatible with any particular cell chemistry. Solar requires a much larger surface area to facilitate the same charge rates as with a plug-in charger, taxing portability and simplicity.

For a standby installation its perfect, which flashaholic you know is a standby installation? :)

I find that the angle of tilt to surface cleanliness to geographical location causes a solar cell to vary its output. From experimentation I have produced direct solar chargers to charge li-ion directly.
To generate steady 2.5W at 5V to charge a li-ion at 500mA, I need a 10W solar panel and a DC/DC converter. The minute my hand, my shadow, or a stray cloud crosses into the light, charging is interrupted by the rapid voltage sag. a 10W panel and additional circuitry feels like carrying a massive cutting board.
 
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Timothybil

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As everyone has said, it is mainly cost, setup knowledge and ease of use that limit the popularity of solar charging. I had originally planned on using a nice little $70 flexible solar panel that put out about 15w to charge my two portable cell phone chargers (you know, the kind that charge from USB and output USB). That would be enough for my phone and tablet, with maybe a USB fan and some LEDS. But my Intellicharger takes 12v as input if not using AC. I planned on getting a USB to 12v DC/DC converter for a total package of about $100. I also priced out a nice system like Chris's but not as ambitious, but that came close to $500 or more, depending on how many panels. So now I don't know. Guess I'll watch prices and see how the savings go.
 

KITROBASKIN

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My two bay NiteCore charger did not like the 12v coming from a 15 watt GoalZero panel for charging 18650's, but a Miller single bay (with the micro(?) USB input) will charge the shorter 18650's and an Xtar MC1 does a great job with seemingly all sizes of 18650. These are not expensive chargers. The panel also charges cell phones with the USB output. I have not used it in a 'disaster' event and understand the limitations of cloudy days, but it does offer an alternative method of keeping the lights on.

It is a bit surprising that no one yet, has mentioned cottonpicker's chargers and portable solar panels over at CPFMarketplace.com, on this thread.

I have successfully used the i2 Intellicharger on my PV system at the small house I built before getting married. (Two 75 watt panels and two AGM batteries somewhat larger than the size of car batteries. I don't remember (Trace?) what controller/distributor/safety management device I am using but it is trouble free)


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ChrisGarrett

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It's not that hard folks and I'm no Nikola Einstein, either.

Get either a small 30w rigid panel, or either a CottonPickers, Brunton, Goal Zero, Global Solar or PowerFilm foldable/rollable panel, a decent controller, some wire, a few attachments and a ~20Ah (or larger deep cycle battery) and you're golden for more than a few charges in an emergency.

Obviously, solar charging presumes that you have some sun light to use.

Chris
 

WalkIntoTheLight

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The solar setups are cool, but probably not practical or the best solution in most cases. It's likely cheaper, easier, and more practical to keep a bunch of extra cells charged up in case you need them. (I keep a drawer full of Eneloops for this.)

You only need a few days worth of batteries. Any longer than that and your neighbours are probably coming to eat you.
 

Wiggle

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I picked up a Cottonpickers solar setup a little while ago. Haven't had much chance to use it but I am planning on using it for bike camping. Combined with a power bank it can make it much easier to maintain power for your phones, batteries etc... while not having access to a grid connection. That being said I'm sure most people would be fine with a small battery supply so part of my motivation is just that I find solar interesting :)

My setup is 3 x 1100 mA @ 5.5V panels. They can be used independently for USB charging up to 1100 mA each or can be combined in parallel providing up to 3.3A. They can also be used in series to produce 1100mA at 15V which can power 12V devices and even charge a small SLA battery. Along with this setup I have a 4x18650 battery box loaded with Panasonic 3400s that charges via USB and can output 2 USB ports and a third barrel type connector that can be adjusted from 5.0-13V in 0.5V increments. I also have a tiny form factor 700mA li-ion charger (USB powered).
 

yoyoman

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I also have a cottonpickers solar setup. I've lived in Switzerland for 4 years and we've never had a power outage - the power lines are underground. So I mainly use the solar setup for truly guilt-free lumens.
 

N8N

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I would think that for charging cells, since most "high end" chargers take a 12VDC input, the real way to do it would be set up whatever solar setup you want to charge a 12VDC SLA battery, then off that run your charger(s) of choice for your other cells. especially if you're using something like a Maha C9000 where if you interrupt power even for a moment it reverts to default 1000mA charge...

I haven't done it primarily because as others have said, it costs money...

now if you want this to be portable e.g. for backpacking you'd have to be more creative
 

ChrisGarrett

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I also have a cottonpickers solar setup. I've lived in Switzerland for 4 years and we've never had a power outage - the power lines are underground. So I mainly use the solar setup for truly guilt-free lumens.

Being in Miami, we've been lucky the past 5-6 years with light hurricane seasons, but back around Katrina and Wilma ('04-'05) times, power went out here for weeks. My GF's went out for 17 days, my uncle/aunt's for 8 days in Boca Raton (they stayed with me!) and my old boss lost his power for ~21 days! I lost mine for 15 hours in Wilma and 18 hours in Andrew, so not a great crisis for rechargeable batteries, but one never knows?

One might be able to go and stay in a hotel (boss) or stay with a family member (uncle/aunt) but often times the hotels are out of power, unless you drive up to Disney World in Orlando, or Naples across on the west coast.

I'm not a prepper per se, but I put together a nice 'car camping' setup with tent, backpack, 1st aid kit, saws, lanterns, sleeping bags, cook stoves, small 900w generator--stuff like that and the solar charger/mother battery kit was just a natural progression, even though I really haven't HAD to use it in over 2 years--it's still there.

To each his own, I guess?

Chris
 

ChrisGarrett

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Very much like wind turbines a complete and utter waste of space.

Come again?

My two panels in the link Norm provided above, fold up into really nothing and that 4 pistol gun case, which holds two of my three batteries and chargers/adapters takes up very little space.

I view my simple and modest system as a one time $400 insurance policy and I probably could have shaved $50-$100 off the bottom line if I had been a bit more patient and bought the panels at auction, off of Ebay ($178 for 2x30w monos with a pair of Y connectors.)

Chris
 

WalkIntoTheLight

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I would think that for charging cells, since most "high end" chargers take a 12VDC input, the real way to do it would be set up whatever solar setup you want to charge a 12VDC SLA battery, then off that run your charger(s) of choice for your other cells. especially if you're using something like a Maha C9000 where if you interrupt power even for a moment it reverts to default 1000mA charge...

I haven't done it primarily because as others have said, it costs money...

How much is a cheap setup that could trickle-charge a 12v SLA battery? I already have the battery (and an inverter), so something that could charge at about 2 amps might be a useful thing to have, if it wasn't very costly. I think it would need to provide about 14 volts to properly charge. I don't really care if it provides a complete charge, just something that could do about 90% of the charge so I could keep a battery from completely discharging.

Of course, 8 amps would be better, but I presume that gets expensive.
 

KITROBASKIN

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Certainly if you want to charge more than one cell at a time, a 12v system would be better. But even though my 15 watt panel can do 12v, the USB connection handles single cells just fine.

'The arrogant shall inherit the Earth' (not)
 

WalkIntoTheLight

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How much is a cheap setup that could trickle-charge a 12v SLA battery? I already have the battery (and an inverter), so something that could charge at about 2 amps might be a useful thing to have, if it wasn't very costly. I think it would need to provide about 14 volts to properly charge. I don't really care if it provides a complete charge, just something that could do about 90% of the charge so I could keep a battery from completely discharging.

Looking around at my local hardware store, it looks like I'd be looking at $250 for a 40 watt system that includes a charge controller. (Reviews seem to put it at about 30 watts in strong sunlight.)

For that price, I could buy another deep-cycle battery, which would give me the equivalent energy that the solar setup would provide in about a week of charging.

So the break-even point seems to be about a week without power. Shorter than that, and it makes better economic sense to just buy another battery and keep it charged. Longer than that (or for use in a remote site where you don't have mains power), the solar setup makes more sense.
 

Norm

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