Recommendation for portable Solar Panel

[mrwhite1]

Here's how I would charge that monster ;-) .....

1. I'd start by getting a nice simple regulated 12v car/lorry lead that plugs in to the cigarette lighter. Should give you some nice portability quick and cheap and will be needed later. (lorries run at 24v, so a charger that runs in either a 12v car or a lorry is a great start)

2. Next, get pretty much any solar panel rated at between 12v and 24v and put a car cigarette socket on the end. The more ma rating, the quicker it will recharge your flashlight. Remember, the regulated lead will take the 12v-24v solar voltage and regulate it to 12v nicely. Personally I wouldn't worry too much about Mono / Poly / Amorphous - I just would go for the nicest looking / best size / price combination that you like. This should now give you a fair bit more portability as you can charge it anywhere you can carry the panel - or sit at the back of your car charging away happily.

3. For more portability / reliability when the sun goes in,you could get a small 'AGM' (no liquid to spill and sealed) 12v battery and small solar "charge controller" to make sure you don't overcharge it. Then even if the sun goes in the small (maybe 12ah) battery can still put some juice in your flashlight. Alternatively get one of those 'jump start' battery chargers / compressors - they have a 17ah battery in them and a 12v socket - can also use it for other puposes then.

Generally if you are using solar, you need to avoid lots of voltage converting (avoid 12v --> 120v -->12v) which inverters lead to as you waste all that precious energy.

None of the panels I sell will be of any use to you with that monster light, but I certainly do think that solar is a viable method of charging batteries on the go. Its just a case of getting a good match for you needs.

For many people a 2w panel is easily carried, yet can put back 400mah into a li-ion in one hour. I don't think thats too shabby

Good luck with your solar search...
CP

Thank you very much!
My case comes with a 12V cigarette lighter adapter, and a lot of the panels I've looked at have female 12V adaptors so it should work.
I really appreciate the very simplified answer as it's much easier for a lay person like myself to understand. So let me see if I get this: As long as the panel with go 12V, the difference in watt / amp (mA) will only effect how fast it will charge? (just want to make sure it wont mess up the lights battery or anything) Is there a certain amount of watt / amp I would need, or as long as it says 12V it will work? I'm assuming at that point it comes down to affordability, and what size would be the most efficient for me to carry? I'll be anxious to use the Kill-A-Watt meter to give some specific examples of the actual power requirements of my light.

yes please do, this is a most informative read lovecpf and I haven't even read all of it yet

gonna print it out and keep reading it later on

I think I have most of the thread information from my emails, unfortunately I may have lost some or they may be out of order slightly, I appologize

 

[cottonpickers]

Hi,

Thats right, if the watt (or amp) rating is low it will be slower charging.

I don't know how many cells the beast has, but if it has 10 cells and they take 2 hours to recharge then I would guess that the supplied charger is a 15-20 watt charger so a 20 watt panel 12v panel would charge in 2 hours in *perfect* conditions. Your watt meter can confirm.

A 10watt panel is a nice size and would in practice probably take a day to charge if angled at the sun. If you overspecced the panel then you just 'waste' energy - it doesn't hurt the beast if more amps are available than it needs (a bit like your house wiring 'offers' far more amps than your lights need.)

 

[mrwhite1]

Hi,

Thats right, if the watt (or amp) rating is low it will be slower charging.

I don't know how many cells the beast has, but if it has 10 cells and they take 2 hours to recharge then I would guess that the supplied charger is a 15-20 watt charger so a 20 watt panel 12v panel would charge in 2 hours in *perfect* conditions. Your watt meter can confirm.

A 10watt panel is a nice size and would in practice probably take a day to charge if angled at the sun. If you overspecced the panel then you just 'waste' energy - it doesn't hurt the beast if more amps are available than it needs (a bit like your house wiring 'offers' far more amps than your lights need.)

I believe the light was rated as a 35W HID. So whenever I get the meter and measure my requirements, The watt rating on meter will tell me how big of a panel to get, and if I get bigger, it will just charge it faster? Does the fact the measurements will be done with 120 AC vs the 12V DC of the panel make a difference?

 

[deadrx7conv]

The kill-a-watt measures AC and not DC. I have one and wouldn't use it at all for this situation.

Since you want to use solar panel to dc battery, you need to do everything possible to avoid inverters as its just a waste of power.

Just about every battery powered device can be charged or powered by a cigarette lighter jack from a vehicle which is 12v. So, DC will be most efficient and get the most bang for the buck. Best bet and simple is a cigarette lighter jack connected to deep cycle 12vdc battery connected to any schottky'd solar panel. Check measurements and pick the biggest battery/panel combo you can carry.

I don't care for the brunton/powerenz/flexcell/... since their dollarower ratios are a joke. Folding is nice if you're a long term hiker. But, for the weekender, I have no problem carrying a couple 5w-20w solar panels in a backpack or hand case. Many 8-20ah sealed batteries can easily be carried.

For your laptop/cellphone..., read the power adapter. All the info you need is there. For the Beast-II, find out how what the batteries are rated for.

 

[ama230]

Ama230 you tell me that they make a flexable pannel that has 15% efficency in power conversion, and point to the exact pannel, and i will give them another try.

i have ones with a dark purple cast to them, and they werent cheap at all, and they suck. so if your telling me that everything has somehow changed, i will try them again, because these are older.

The mono or poly do not collect ambient light the amorphous do as well as direct sunlight nd look at a
many amorphous pannels have built in bypass diodes, and therfore can cope with shading sitatuations.
But
there isnt one place on the web, even from sellers, that would say a amorphous is anywhere near as efficent as even a poly.

show me ONE research paper even from the manufacture or seller that makes the claim that that they have a flexable pannel of any sort, that Per square foot can supply more energy at any level of light.
you have to have a KITE of these flexable pannels , and that is what it becomes out in the wind

Try and look at a CiGs or CiS panel as these have an efficiency of 15% and they are a thin film and come in flexible arrays. Not everybody needs a big v8 to do the job as thin films have gone along ways and are under rated. Take a look around and you'll be suprised. Manufacturer is the key here as cheap ones are going to always do poorly and not last.

And for mrwhite, take a look at any of the brunton foldable or flexible 12watt+ panels as this would more than meet and exceed what you need to do. Just get one at a good store as you can always return it if anything were to arise, which there shouldn't be. They come with the 12v plug built in and start at 800mA and go up. Weather proof and will do best in all lighting conditions. They seem to favor the amorphous and CiGs technologies and are ultraportable.
http://www.amazon.com/dp/B000GEFFBO/?tag=cpf0b6-20

This one is 26watts... And comes with all the plus you need and the sunforce charge controller has the highest ratings and is pretty cheap but is not really needed as your surefire only takes less than an amp to charge. Its basically for when you need to hook up a couple of these arrays and are going to run up to 7amps out to something.

rx7 - is right for the killawatt deal as this is for the ac plug supplied and is going to require a much larger panel as you are converting 12vdc to 110ac then to 12vdc again and would require an decent inverter which is added cost. If the surefire beast came with a 12v plug then its not needed as the panel above will do just fine. It supplies 15.4v @ 1.6amps wich is great for something the size of a wallet.

rx7 - If you get a mono or poly lower than 5$/watt it is going to have a lower efficiency than the thin films suggested, thats just the trade off. It just isn't going to give you 15% because you got it for cheap, its cheap because it has a lower grade silicon(lower efficiency) and no anti reflective film and protection diodes. Also when you get a smaller panel(s) you are going to have to pay more for the quality ones because they just aren't going to be cost effective for the manufacturer. They have huge crystals of silicon and the demand for smaller ones is just to low to make money. Its just like the bulk theory as its cost money to cut silicon and then package it.

Its a choice of wanting to carry a single large panel or a portable one as suggested as you have to point us in the direction you want.

Please answer the following if you don't mind:

Starting with max size of panel wanted:

What your li-ion battery specs are for the beast:

Whats your budget(max you want to spend):

Charger rating on the ac plug or dc plug(it should be in small print and will say dc supplied voltage and then current next to it):

How fast do you want it to charge:



Hope this helps..
Eric

 

[VidPro]

thanks.

 

[deadrx7conv]

For the cost of the 26w Brunton, you could get 3 of these and you only need 1 for experimenting with:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&Item=270591279729

Or for a little more cushion, a 42 watt'er is only a little more than the Brunton:
http://cgi.ebay.com/42-Watt-Foldable-Solar-Panel-/160426067880

I could care less whether its Cigs/Amorphous/Poly/Mono panel. You need as many watts as possible. Pretty simple. And unless you're perfect at aiming, 'real sunlight' is only about 4hrs on a good bright sunny day.

Simple math power requirements looking at my batteries here for the cellphone/laptop/HID light:
Cellphone 10whr + Laptop 50whr + HID light 100whr= 160whr
160whr/4hrs of sunlight=40watt solar panel to charge everything once a day. So, how many hours do you need to use your flashlight each night?

Use the 'most efficient' electronics you can find.

 

[mrwhite1]

Here's a picture of it.
The light usually lasts close to 2 hours at it's highest setting.
I would like to be able to charge it at least once during the day relatively quickly... and possibly recharge it again at night from a battery source of some type... not sure what battery requirements I would need though

 

[deadrx7conv]

Once a day relatively quickly are the key words.
Relatively quickly won't happen from solar panel all by itself unless its big. You'll have to charge off a battery being charged by the panel.

How big of a solar panel can you carry? if you're hiking, then the 20w, 26w, or 42w fold-able is a good start if it isn't too big.

2hrs for the HID on high? is it a 50watt HID? 2x50=100+whr
Assume so, within 3hrs, it'll be charged fully directly by the sun with the 42w panel. Should charge faster connected to a 12v battery.
So, get a 10ah-20ah 12v sealed UPS battery which is charged by the panel, and charge your light from the solar charged battery. Any residual sunlight, or free time, can be use to keep the deep-cycle battery topped off in case you need to recharge in the middle of the night.

The solar panel and your flashlight have red/black alligator clips. Connect them to a battery, like a UPS battery RBC4, and enjoy.

When it comes to solar, I will always recommend 'more' than what you need. Its for you to test whether you have enough panel and storage battery.

Simple economical test(with minimal cost components less than what I recommend but should work):
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&Item=270591279729
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=360288869388
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=360297411643

I recommend charge controllers because the 'LED' colors will let you know if its working. Connect solar panel to charge controller. Connect charge controller to deep cycle battery. Connect your flashlight's 12vdc clips to the same battery. When flashlight says its fully charged, disconnect flashlight charging clips but leave the solar panel/controller connected to deep cycle battery to fully top off. The charge controller prevents overcharging the deep cycle battery.

Make sure any/all batteries are fully charged prior to any expeditions. And, test your solar panel/deepcycle battery/controller combination at home. Up size the solar panel & battery as needed.

 

[ama230]

For the cost of the 26w Brunton, you could get 3 of these and you only need 1 for experimenting with:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&Item=270591279729

Or for a little more cushion, a 42 watt'er is only a little more than the Brunton:
http://cgi.ebay.com/42-Watt-Foldable-Solar-Panel-/160426067880

I could care less whether its Cigs/Amorphous/Poly/Mono panel. You need as many watts as possible. Pretty simple. And unless you're perfect at aiming, 'real sunlight' is only about 4hrs on a good bright sunny day.

Simple math power requirements looking at my batteries here for the cellphone/laptop/HID light:
Cellphone 10whr + Laptop 50whr + HID light 100whr= 160whr
160whr/4hrs of sunlight=40watt solar panel to charge everything once a day. So, how many hours do you need to use your flashlight each night?

Use the 'most efficient' electronics you can find.

The reason I had stated the amorphous/cis panel are their duty time. They are usable in 8-10+ hours of the day and will stay within 90% of their specs in all lighting conditions. They are also a lot smaller than carrying a 40watt mono or poly as its going to be at least going to be 3ft sq and its not going to fit into a glove compartment as he stated.

I had listed the 42 watt ebay panels earlier in this post with the cable accessory kit. Looks like he uses powerenz.com products which look very good and they use cigs panels which are the highest efficiency thin film type.

I had listed the brunton because he had pointed them out. As far as the powerenz and powerfilm, they seem to have the best exposure. The ebay one seems to be cheaper by half than what the actual site is asking too so its a bargain. Ill list is again but it comes with the plugs and stuff, just need the small battery as cotton said, a nice agm battery that wally world sells in the battery section for motor cycles or a website but its going to cost a few with shipping for weight.
http://cgi.ebay.com/42-Watt-Foldabl...498?pt=LH_DefaultDomain_0&hash=item2c56dea79a

This seems to the best deal in terms of portability and collecting light for 2x what a mono or poly would be able to do and is a lot cheaper.

Then if you don't care for portability: This is a 50watt but is only going to work on average 5 hours a day with direct light(sunny days).Its also grade A silicon as its the best you can get, commercially speaking. Its also a great deal as its around the 2$/watt the market is at right now, it may be higher but times are hard and they have to meet market demands. A year ago it was 3$/watt. As you can see this is barely putting out more current than a Cigs panel as its one piece of monocrystalline silicon. Just have to be careful where you put this as its going to need every tiny drop of sunlight it can get. The flexible ones aren't picky at all... This panel also requires that you hook up your 12v clips to the leads and put in direct sunlight.
http://cgi.ebay.com/ws/eBayISAPI.dl...fa00139&itemid=290467850467&ff4=263602_263622

It sucks that you didnt get anyspecs on the battery or charging setup but its alot better as its straight foward. So its up to you on how big of a setup you want, anything above 26watts will charge a small dead battery in about 4 hours. Then the 42 watt panel will do it in under 2 hours with all lighting conditions. Then this should charge you surefire a handful of times so you can rest in the meantime as i'm sure its going to take just as long to just charge the beast as they charge at low current to save battery life.

Here's a good battery with ample size too. 37 bucks for 6500mah and they warranty their products.
http://www.batteriesinaflash.com/mo...h-50cca-motorcycle-battery-replaces-12n6-5-3b

The battery is going to be for when you need to charge right then and there in any condition and will have a handful of full charges for the beast. Then when its done it would only require that you charge it for a couple hours using the 42 watt or the 50 watt panels. Just have to choose on aesthetics.

Also rx7, do you own an rx7?
if so what year and what motor?
Any mods
any plans

I had a b18b1 fully built turbo with a top mount turbo t60/63 @ 8lbs 220hp/210tq for emissions and never got around to injectors. It had a crappy integra shell but it was my first turbo project. Its fun stuff but expensive. Anyways I want to hear because you dont see many rx7's around. Rotarys are sick!!! and sound bad ace!!!

 

[VidPro]

http://www.ctsolar.com/104wbargainsolarpanel.aspx
for my 4.3" GPS i only needed 1/2 of one of these, to keep it going non stop and charge my huge internal battery. the only lightweight way of carrying glass is with the epoxy stuff.

 

[Jfet]

hey guys. A bit late to this thread, but I thought I would post my real world hiking results using the flexible solar panels.

First, I own the Brunton Solaris 26 watt CIGS panel, the Brunton 6 watt CIGS panel, and the Powerfilm 14 watt rollable panel (amorphous thin film).

All three perform fairly well, but the Brunton Solaris 26 is by far the winner. It seems underrated in power output, or the other two are overrated. In a Seattle sunny day I get nearly 25 watts out of the Solaris 26, while only getting 4 watts from the 6 watt and about 11 watts from the powerfilm 14 watt. Seattle is not known for high insolation either, so I am guessing the panels are not getting 1000 watts/m^2

Anyway, the Powerfilm is probably the most rugged, but is about 17 ounces. The Brunton 26 is right around 25 ounces and the Brunton 6 is 7 ounces.

I have day hiked with all three while using a Fluke 289 multimeter to log power consumption into a resistive load. They all deliver some power even when in indirect light or heavy clouds. As an example, on a rainy overcast day, the Brunton 26 will still put out about 2 to 4 watts depending on orientation. The Powerfilm 14 rollable fits a bit better on the backpack to use while hiking.

I recently did the west coast trail on Vancouver Island, BC. We took 7 days to do the 75km hike (seems longer than 75km) and I took the Brunton 26 to keep my smartphone (Nexus One functioning as a phone, gps, ebook reader, and camera all in one) fully charged. I knew this was way overkill but I wanted to play with my "toy" and see how it might work in that crap climate. I also used a Sanyo Eneloop usb AA/AAA charger powered off the panel to keep our flashlight batteries topped off (charger is about 1 ounce and not much bigger than two AA batteries, very cute).

With all of the ladders, trees and such, I didn't get a lot of charging time per day, but when I did get around to charging (usually after 4pm), the Brunton 26 would bring my Nexus One up to full charge in an hour or two. It uses a 3.6V 1400mA Li-ion battery, so I was at least getting several watts out of the Brunton 26. I used a car lighter DC-DC converter to buck the 15-20 volt output down to usb 5V for the phone and Eneloop charger. I don't think there was a single sunny day on our hike

All in all, it was not really worth the weight for such a trip, but if I had more gadgets or really liked taking pictures, I could see it balancing out vs carrying extra batteries in about 10+ day hikes. Even if you figured only getting 26 WH a day (so one hour in full sun), that would be equivalent to about 10 NiMh AA cells which i think are around one ounce each. The panel is 26 ounces, so on a 2 week hike it could theoretically provide the electrical equivalent of 16 pounds of NiMh batteries if used one hour a day in full sun. If you were hiking in SW USA the Brunton 26 would be a no-brainer if you needed that kind of power (maybe carrying a laptop for some reason, lol?).

I got the Brunton 26 for about $260 at thenerds, and I got the Powerfilm 14 rollable for $170 at defender.com. The Brunton 6 I got at REI for $25 clearance because they were getting rid of this model (the I6, which is the same thing as the regular but also comes with a ipod cable).

Just wanted to share some real world testing.

 

[SemiMan]

Jfet ... thank you for the thoughtful reply! It was about the only one worth it in this stream...

AMA230 ... you are talking out your butt. No way you have years of real experience with the stuff you are spouting....


1) Thin film manufacturers like to spout about how their product will produce more total power versus a crystalline panel. The reality is that this is NEVER proven out in testing. The best tested panel is a poly/multicrystalline. The second best is a First Solar thin film... then some other mono crystalline.. and a ways down amorphous silicon.

2) Amorphous silicon DOES NOT collect a wider amount of the spectrum. In fact, it collects a much narrower range compared to virtually every other solar technology, but it collects mainly in the blue end of the spectrum which is one of the reasons why it does better in overcast situations where the spectrum is blue slanted. Recent tandem/micromorph amorphous panels do collect more of the spectrum versus plain amorphous.

Technically crystalline cells generate electron-hole pairs with blue light as well, but unfortunately recombination near the surface eliminates these. Selective emitter gains some of this back.

3) The ABSOLUTELY best shipping thin film panel is barely over 11% (Global Solar). A CIGS panel.

4) Gallium Arsenide is only used for very expensive concentrator cells currently.

5) Amorphous and other thin film cells do do better at low light levels. However, that is not so much about sun angles, diffusion, etc. as it does about responsivity versus irradiation levels. Crystalline solar cells have poor efficiency at low irradiation levels.

6) "90% of their specs in all lighting conditions?" ..... What the heck does that mean. Max efficiency is 11%. To get 20 watts out, you need to hit it with almost 200 watts no matter thin film or not.

7) Amorphous, etc. all thin film are not flexible because of a loose lattice structure, they are flexible because the active layer is very thin allowing it to be put on an flexible substrate. Crystalline silicon when it gets down to 30-40um becomes flexible too!

8) Not all thin film panels deal well with shading. In fact, MANY portable ones do not deal well with it all. Amorphous thin film panels do well with shading as they have individual cells that run the length of the panel. Hence if you shade half the panel, you can still get half the current. Crystalline panels and MANY portable thin film panels are made up of series connected cells which all have the same shading issues. If you shade one cell, you lose the whole panel.

9) Sunpower and Sanyo DO NOT make thin film panels. They make crystalline panels! ... well Sanyo has started to make some thin film stuff, but very limited market exposure. Sunpower makes the highest efficiency crystalline cells in production, period. Obviously you have little clue about who the thin film players are.

10) "If you need current = Amorphous or thin film panels, If you need voltage = Poly(cheapest) or mono crystalline, or Copper Indium Sulfide or if you can afford it Gallium Nitride" ... COMPLETELY WRONG AND BACKWARDS

11) AR coating mainly affects directed sunlight, not brewster angle losses.

12) "The mono or poly do not collect ambient light the amorphous do as well as direct sunlight so in terms of versatility and cost amorphous is the best." ..... Not sure what you mean by ambient light, but mono/poly certainly collects diffuse light. "Ambient" light contains so little energy as to be almost useless ... except for running a calculator.

13) "not as good in direct since the efficiency is less being a thin film as photon pass right through the thin film " .... this is not why thin films are less efficient. Thin films of CIGS material are effectively opaque.

14) "The non name brand ones do not, there are only a few great manufacturers that do this. As its cheaper to have a few at a buck and replace them, then making a really good one that takes 10 bucks to make that is going to cause the customer to not need to buy anymore. YOu have to watch this as this is the case with all replicas." ... WHAT??? !!!! ... Generally any panel that is intended to be used in series with other panels will have bypass diodes. Panels that are intended to be used on their own in generally do not have bypass diodes as unless the full panel is producing voltage, then the total voltage will not be enough for the load. Hence panels that are targeted at only 12V battery charging rarely have bypass diodes. Higher voltage panels / on grid panels always have bypass diodes.

15) " 10+ hours of collecting light(Amorphous), 5hrs of collecting light(mono/poly/cis/GaN). The crystalline modules are limited by the amount of time they get direct sunlight(when the sun is directly over the panel and has less than a 45 degree pitch from exposure all the way up to ninety(which is perpendicular to the panel). An amorphous works from a little before sun up to a little past sun down with collecting light. " ..... Obviously you have never seen the power output report on a solar installation using crystalline panels ... and 8+ hours of collection. When the sky is not cloudy, most of the energy is in the directed beam from the sun. Whether thin film or crystalline silicon, it is all about getting that light into the cell and that is all about optical properties. Both have the same issues with surface reflection at high angles. Thin film as stated generally has better output at low light levels, but in general there is not a lot of energy here. That said, crystalline silicon has better surface structure for capturing off angle light. It can be a wash.

Stop passing yourself off as an expert when it is clear to someone who does not even consider themselves and expert that you have no better than a cursory understanding clearly evident from you frequent mixing of what feature applies to what technology.



And at the end of the day, all of this is meaningless for the intended application. Since the goal was portable, a flexible thin film solution is the only solution and the Brunton 26 is a reasonable solution.

 

[SemiMan]

Of course, you are likely better off buying the Sunlinq 25 (Global Solar) which is essentially the same as the Brunton 26. Both contain Global Solar cells I believe. They may even be the same packaging?

Search around. You can find them as low as $300 on the web.

Just looked at them again. I would place high odds they are the same product with Brunton likely private labelling the Global Solar product.

Semiman

 

[Jfet]

Is the Sunlinq 25 cheaper than the Brunton 26?

http://www.thenerds.net/BRUNTON.CHARGER_SOLARIS_26_WATT_FOLDABLE.FSOLARIS26.html

$263.99 for the Brunton...this is where I got mine.

 

[SemiMan]

Is the Sunlinq 25 cheaper than the Brunton 26?

http://www.thenerds.net/BRUNTON.CHARGER_SOLARIS_26_WATT_FOLDABLE.FSOLARIS26.html

$263.99 for the Brunton...this is where I got mine.

Good find. I had not seen the Brunton that low. Made a quick call and yes these two are the same thing so whatever you can find cheaper is best.

Semiman