e-bay solar panel completed pictures

[picmacmillan]

finally finished one ebay panel....

I don't know if it is worth all the effort to buy these e-bay cells or not....the panels i built work out to about .75 cents canadian per watt if all the other parts needed are donated(which they were)....this does not count for your time which is a big factor in this...also, they aren't even up yet and i haven't figured out how to keep them from condensation  damage......this will require some more testing.....at this point i see that canadian tire has a 15 watt panel on sale this week for 99 bucks canadian.....so, i wonder with all the trouble with these things, and the serious amount of time if it is all worth it....below is some of my data

- each of my panels has 28 cells in them,(which is app. 1/2 pound)

-(1/2 pound was $17.50 u.s dollars)plus shipping plus canadian brokerage fees etc.

-i can build 1 panel for $17.50 plus all the solder, time etc......

- in conclusion, i guess i would save about $80.00 per panel, but personlly, i think it might be just as wise to buy a store bought panel as it is finished with no crap, and a warranty, and will work for sure.....anyone agree?...    pickster

[Geek]

Sounds like a good deal to me.

But the time can be a killer.

How much time do you have in the panel?

If you haven't allready posted the url for the solar cells please do.

If you can get the panel sealed you could just fill it with a dry gas. Leaks would be the bigest problem.

Heres a idea (hot off the press(which means i really havent thought it through much so it might be stupid)) but maybe you could use a chemical that absorbes water to keep it from condensing at cooler temps and just replace the chemical it once in a while as needed.

Geek

[picmacmillan]

i forgot the main purpose of this board is to share what i have learned on this project, especially if i can save someone some grief..below are some suggestions when building these panels.

-do all soldering of wires "before" cells are set in place permanently with adhesive etc..also, cut all wires to desired length and have the ends peeled and ready for connection to the next row of cells

-use a red wire as + exit wire and use black wire for - exit wire....,this will ensure you remember which one is which in case you have to work on it again.

-i am going to make two panels in parallel and the rest in series....i am going to use a differnet coloured caulking on the two parallel panels so i know which ones they are down the road....i would suggest doing something(ie. colour code) so that you know very clearly that these two are different.

-when i soldered the cells together, i put my roll of solder on the ground and pulled it up towards the bench i was working on...i found when i had the roll on the bench, it would occasionally get caught on a corner of a cell and it was possible to do damage to the completed row of cells....

-as you finish one group of cells it may be alot easier to solder the wires for the next group right then as you make your row....don't wait and do them all at the final assembly...any movement may damage the cells...and does...

- a well ventilated area is needed as all the smoke from the soldering gun will go right in your face.

-use a heavier wire as the connecting wire from one group of cells to the next...this wire will have to hold more amps so you don't want to have this wire to small and fry once you're done....

-you need a pretty big work area to do the production of these panels or you will be in poop like me.

take care.....pickster

[picmacmillan]

ya, thanks for the ideas....some suggested using silicon packets inside the glass to absorb the moisture, others suggested gas, ie. argon etc...a window company near me uses krypton gas in there windows....group 7 on the periodic table if i remember right....i think all those gases may work, radon, argon, krypton...i might try internetfreds idea and fill them with baby oil or something just to try it out..anyhow thanks for the ideas....pickster

[picmacmillan]

to find the solar cells on ebay..just go to ebay and type in broken chipped solar cells, and the engineroom will show up....the sellsers name is cusdn and you can email them from the e-bay site...take care...pickster

[Aelric]

Just an idea... where I used to work on some large towers we used nitrogen gas pumped up the tower to our microwave gear.  The purpose was two fold in that for one the nitrogen helped keep out other things like humid air or water and 2 it helped you know if you had a leak.   If there was a leak anywhere then you would loose pressure.  If you sealed the panels and had Nitrogen gas in them then you could easily tell if there was a leak.  Trick is to find where hehehehe.

[richhagen]

I built one a while ago and was disappointed that condensation built up in it and electrolytic destruction of some of the cells followed.  It was two sheets of glass sealed with silicone.  I commented about it a while ago and got a plethora of suggestions and ideas to prevent the problem in the future(butyl calk, mineral oil, intert gas, ect).  I've been busy with lots of other projects and havn't had a chance to fix it up yet.  I'm watching the other projects like yours with interest.  Anyway, my suggestions are to mount the panel for testing where you can keep a close eye on it, and if condensation starts, take it down and implement a fix before permanent damage is done.  Rich Hagen

[picmacmillan]

thanks rich for the photo.....that is exactly what i am looking out for.....i have heard of some using wd40 on the panels but i know there is water in that because i cleaned my guns with it before when i was out of gun oil,....didn't take long, a couple days i guess and here comes mr. oxidization(rust)....i am going to experiment with three layers of glass, or a mixture of 2 layers of glass covered by two layers of plastic above the glass....the method to my madness is if i am correct, the condensation will collect between the two layers of plastic and run out the bottom... this i hope will minimize the water in between the glass where the cells are..or better yet, eliminate it.....we will see and i will post my results...

 oh, one more thing...i am also going to fill one with baby oil, vegetable oil, or something along that line, in to one panel just to see what happens....i know when we test auto parts for instance, we will set the part(plastic) or whatever outside in the elements, just to see it's overall reaction to harsh weather conditions.....this experiment sometimes is over a period of two years....anyhow have a good one.......pickster

[debequechute]

Wouldn't it be possible to spray a UV-stabilized clear-coat on the individual cells before mounting (and after soldering)? Seems like that should eliminate any problems with condensation hurting the cells. Is there a well-known and long-lasting product that would work for that?

[Tom in NH]

Awesome, Pic. Congratulations. Break a bottle of champagne over it or something (whoa. maybe you better not, what with glass houses and all.) I'm pretty convinced you can't make panels for less than you can buy them if you count your time as money. You also have to count all your boo boos, which for me is often costly. However, now that I have a process figured out and a large supply of cells and plexiglas, I figure I have about US$250 in the materials for four 72-cell panels. It would take me four evenings to assemble them, about 24 hours total. There goes my savings.

But... What would have I been doing had I not been staying up late at night making panels? Probably staying up late at night playing on the computer or watching the boob tube. Who knows more about the guts of a solar AE system, me or somebody who just buys the panels? Does going to the trouble to make your own represent bother or fun?

There is a lot more than mere money at stake.  --Tom

[Volvo farmer]

Worth the time? Good question. Store-bought panels are pretty nifty. 20 year warranty, nice aluminum frames, no condensation problems. What you got for your time is a bunch of experience. Experience is also a nifty thing that cannot be bought for any price if you really need it right now. I've got a few store-bought panels but don't have any idea how to solder cells or wire them into useable arrays, so perhaps your time was well spent learning about these things.

Money is not the measure of all things.

Volvo farmer

[iFred]

Picky, If you are not enjoying what you are doing then why do it? That simple. This is a thing called "a labor of love" , to which you can't completely add your labor as the final cost, not to mention the learning experiences that you are gaining as a result, to which you cannot put a price tag on anyway.

In one week, in my spare time, at night for a few hours each night, I built all 12 panels with no problems. I took my time, thought it out and though of a strategy, I spent some more time thinking and when all was said and done, I did what was necessary to do and did it right the first time. I screwed up only unlucky #13, one panel. The rest are A ok as you have witnessed yourself in person. No moisture problems, no real problems that I could not solve.

What I believe you are not seeing yet is the end result. You now have a 45 watt panel which cost less then a 15 watt panel at $99. And when the sun shines and you see the power coming out of those panels, i think you'll change your mind real quick. So what do you have to loose but some spare time?

And as for wiring, I am wiring all in sets of two as series/parallel. But just to help you out, here is a wiring circuit for the panels, Enjoy!

[nothing to lose]

"But... What would have I been doing had I not been staying up late at night making panels? Probably staying up late at night playing on the computer or watching the boob tube. Who knows more about the guts of a solar AE system, me or somebody who just buys the panels? Does going to the trouble to make your own represent bother or fun?

There is a lot more than mere money at stake.  --Tom"

I agree with that alot! Also when considering time involved do it realistically, most people don't! I used to do alot of money counseling with people and I know the average person does not think about these things correctly. Of course most of the people here I would call above average though.

Let's say you earn $20 an hour at work, ok what all is that? Taxes, auto expenses to get back and forth, lunch money, work clothes ect... Ok for some people not to wise with money and tax deductions that hourly rate just dropped to about $15 (or less)after taxes and everything else.

So you invest 10 hours time into building a pannel, = $150 (useable pay) But you wouldn't have made that anyway since you did it while NOT working.

Now if you figure it would have cost only an extra $200 to buy it ready made, well remember we just figured the take home pay was $15 an hour, so that means you would have had to have worked for $200/$15hr = 13.33hrs. So besides saving REAL money you also saved 3.33 work hours

Up to you rather the extra $200 for a pre-built pannel includes taxes or if they were extra. The values change, some people may have more or less take home pay, and the cost of the pannels vary and so will how much was saved building your own. But that's the basic way I figure things to get a realistic idea if it was worthwhile.

You should see me explain why paying $25 for an oil change at jiffey oil mart costs a person $100 an hour labour!! Buy the oil and filter while doing other shopping, nothing except cost of parts is involved (about $10). Take 10 minutes to change it when your not doing anything else. Save $15 in 10 minutes, X 6 = $90 an hour. Now for the average person taking home $9 an hour cash pay after all expences thats 10 hours of real work they have to do if they owned 6 cars. For people that have the tools already and the little knowledge needed it's rediculous to be paying that!! People who can't do it themselfs or make $25hr take home may have an excuse.

 I have over 30 vehicles, driving about 6 now, didn't take me long to figure that out

 Not sure I have the patience to build a pannel. That's a nice looking pannel, looks like a good job putting it together. Thanks for the info and advice. Now that I rented the large rock house when I get everything set up I will have a lot of space to work. That's been my biggest problem getting anything done, no indoor work area. Just too cramped here for anything. I will be buying 1lb of these cells also and giving it a shot, if I get something working with those I'll go the bigger packs.

 For now (this time of year) That rock house gets a ton of sun all day long on one side (if it's shineing) and that side has 4 Large windows.

 Has anyone tried building these pannels in like a window unit?? I am thinking I don't want those windows anyway really, so I may hang pannels almost full size blocking them off. Any  heat the cells make will heat the room, also I am building solar heaters to hang under the windows outside to heat the rooms. Since I don't own this house I can't do anything permanant to it

 I figure being indoors in the window I could use just a heavy backing to mount them and condinsation should not be a problem right away. Later I'll mount them for outside use and put them on a roof at home, would also help shade the roof keeping the house cooler.

I know in the window like that they will not perform the best, but the sun does shine in them brightly all day long the entire top to bottom, just the angle changes from side to side.

Do those of you building these cell pannels think I can fit enough cells into a normal large window space and get enough power to be worth it?? Provided I get the sun of course.

[tecker]

   Making power from scratch is the drive for me along with watching a generation of doers take charge of the planet.

[RatOmeter]

Everyone, carefully read the label on your can of WD40 (or equivilent).  It is to loosen rusted/siezed parts.  As a lubricant or environmental shield it is much less than ideal. Most of its components evaporate, leaving almost nothing behind.

Got a bicycle?  Do this experiment. Pour motor oil on the chain or, better yet, swab it with some kind of bearing grease.  Go ride it a bunch, but make sure the chain gets dirty and leave it outside in the weather for a month or 2. Now clean that chain with lotsa WD40... get it good and clean and well covered with WD40.

Now, repeat the riding and sitting the bike outdoors part. What do you get?  A rusty chain.  WD40 is not intended to protect anything.

[picmacmillan]

thanks all for yor replies..i have recieved some valuable information on these posts...thanks to fred also for all the help and everyone else for their ideas.....today is a new day and if i had to do over....i would....especially when i would have been doing just what was said....watching the boob tube or something....i thought i learned alot in school in the mechanical engineering feild, but here it is actually something i really want to learn....all of it.....sometimes my head hurts from thinking here.....one thing i do know is i have to get back in to the books and recall all these formula's i need here....then i will be able to lead a little more instead of follow......there is a great deal of satisfaction that goes with doing this type of thing.....like i said before it is good clean fun...and at $17.50 for a complete panel, it is definately worth it...here is the 2nd panel i made with the broken, chipped cells...it took very little time compared to the first one......thanks again all....pickster

[tcrenshaw]

I was also worried about the effect of condensation. I was using inert gas to flush out the moisture.

Because like Fred and just about everyone else, I want to put these panels together as cheap as possible, so I stopped using that method. Sealing the panels completely was not going to work either because moisture would somehow find its way back into the panels. Completely open panels were also not to my liking.

My panels are 18x2 so they are tall and narrow. What seems to be working so far with this configuration is placing a small hole at the very bottom of the panel between the two columns of cells and one at the top. I'm using wood as my back board so I just drill through it. I do see condensation but only for ten or twenty minutes in the morning when the panels get their first bit of sun light on them. They quickly clear. What seems to be happening is that as the panel heats up the hot air is escaping out the top of the panel, pulling air in through the bottom. This movement of air clears the glass of condensation. I may put some type of filter over the holes because I don't want dirt in the panels.

No matter what, it appears that these home made panels will need more maintenance then commercial panels.

[iFred]

It is amazing to me that you thought about that and then didn't catch what I said all along about the use of the WD40. First, go to my web page and read what I posted. What I said was that I put a thin coat of spray on the cells and then let them dry?... now why would I do that? Besides which, there are no moving parts in a solar panel, so vis a vis, no rust.

Firstly, the WD40 puts a protective limited time span thin film on the cells, this was done so that when the cells where put together, the sealant would not corrode the wires nor effect the cells during the drying process.

The applied thin film that was applied was extremely thin, a once over and done. just enough so that when the panels are drying, the moisture contained within and the temperature differences would not cause problems during the sealant curing. this was the primary focus of the WD40. When applied, after a month or so of drying and curing a residue would be left behind, minor but not visible. which would be flushed later by a good type of mineral oil or baby type oil. And again, this was miss interpreted as well. My spacing is so small between the glass plates that a few drops will more then do when I say filling the cell with oil. The space is 3/16 minus the cell's and minus the wiring.

To add to this, I am now in the third month of creating these cells, I can say that there has been absolutely no moisture or corrosion as of yet. Also the WD40 is starting to finally dissipate and vaporize leaving behind, nothing but a clean cell.

There is no relationship between putting wd40 on cells and putting it on a bike.

[pyrocasto]

The reason I do it is the love for RE and homeprodjects both. I am a big do it yourselfer and I build everything I can since I have a wood shop(wakeboard, solar panels, ect...). I also got the most expensive items for these panels for free: the wood and the glass(if you use wood at least, which I do).

When I figure out the price it would take someone to build one of my panels, if you include your time then it would go over the price of a bought panel(depending on how fast you can work). I dont count my time, because I learn and have a blast, and a sense of achievement in doing stuff like this.

Here's a list:

90 cells:               $114

wood(1sht):             $30 a 4'x8' sheet

glass:                  $20

double sided tape:      $10

Resin:                  $10

Angle aluminum:         $15

Solder:                 $5

Copper Tabbing:         $10

   Total =              $214+-

Now, if you decide to build a few, the price starts dropping even more.

Now if you add in that I got 4 panels of glass for free(so far), and free scrap wood, and also bought 5lbs of cells instead of going by the pound, then it's much better.

For me:

90cells:  $82

Wood:     Free

Glass:    Free

Resinx3:  $25

Everything else:

  Total:  $130+-

Now tell me you wouldnt build a good panel, that should last for years, for less than a $1 a watt and it still look great. I'm thinking of putting it on Ebay, maybe with a high reserve, just to see what I could get for it and if I would sell it or not.

If so, I might have to figure out how to get 25lbs or more(dont want to drive there from NC).

[whatsnext]

This is probably a dumb question. Why is everyone trying to seal them up at all? Why not leave the back open? When the sun it out the slightly hotter panel will not allow condensation to form. Any that does form overnight just goes away when the sun shines. Allowing just a bit of air to come and go seems like a recipe for water formation. Leaving the back wide open allows any condensation to leave straight off.

John......

[Tom in NH]

Not dumb at all. I'm a fan of ventilation too.

http://www.fieldlines.com/story/2005/1/5/51211/79555

--Tom

[fishfarm]

I've been reading with interest everyone's experiences with engine room's solar cells and thought I should share mine as well. I live off-grid (12.5 kW diesel generator, Trace SW4024 inverter and 24 Trojan T-105 batteries) and have been watching the price of commercial solar panels for some time, hoping they would drop significantly on new technology or increased competition; target price $2.00/watt. But, continually rising fuel costs and international uncertainties caused me to go ahead with home made panels as an interim solution. I say interim because I decided up front not to try to build commercial-type panels, but to treat it as an experiment, minimize costs, accepting potentially shorter life spans and "bridge the gap" to the next generation of cheaper commercial panels (organic dye based, perhaps?).

Anyway, I built my panels in groups of 210 cells to fit on a 4'x8' sheet of plywood. Actually, each 4'x8' sheet is three 70-cell panels approximately 30"x48". Each 70-cell panel is made of five 14-cell strings approximately 6"x48". How I made the strings differs from what I've seen on the discussion boards. I basically laminated them in a product sometimes called "sign vinyl". I got a sample from my local sign shop, tried it on a couple of damaged cells and decided to go with it. Specifically, the product I used is "ORACAL 651 SERIES 2.5 mil 5 YR HIGH GLOSS INTERMEDIATE FILM". Using 15" x 50 yard rolls, I cut it into 50" lengths (to overlap my 48" plywood and frame), then cut the 50' lengths into 9" and 6" strips. The 9" strip is laid flat, adhesive side up (it's got a paper backing), cells placed face down (carefully, you can't move them once they are down), soldered the cells together, the 1.5" flaps are laid back over the sides of the soldered cells and the 6" strip is placed over this, completely sealing them. Only the + and - end connectors are exposed. I soldered the strings together using 18 gauge speaker wire, stapled the string ends to the 4x8 frame and wired them up. I bought some 0-80 amp DC ammeters on ebay to monitor the panels and used a 16 qt. plastic container for a combiner/meter box.

Per engineroom's specs, peak power for 210 cells should be around 285 watts. The panels show 38 volts at 10 amps short circuit, produce 32 volts at power and have shown a peak amperage of about 6 amps, resulting in 192 watts, say 200 peak watts in round numbers, about 70% of rated power. All in all, not bad. I wound up building eight 4x8 sheets using 40 pounds of cells. I used both cracked cells and partial cells, resulting in some variation between the panels. Smashed cells and cells less than about 75% whole I did not use. I used the solder ribbons from the smashed cells for the + end connectors on the strings. Right now at 2:00 pm on a clear day after a foggy morning in west central Florida, I'm getting a total of 40 amps at 32 volts (at the panels), or 1280 of my estimated 1600 peak watts. Total project cost was $2068.89 (approx $1.30 per peak watt); total project time was 16 weeks. Very satisfying to complete, but soldering 1680 solar cells did get tedious at times.

Before installing the panels, my average weekly generator run time was just over 23 hours or about 3 1/4 hours per day to charge the batteries. Last week it was 1.1 hours; the week before it was 1.3 hours. The average weekly run time in the 6 weeks I've had all eight panels installed is 2.2 hours, better than a 90% reduction. Many days I do not have to run the generator at all, and if I had more energy efficient appliances, perhaps then only under extreme circumstances. Estimated payback is less than 2 years, depending on the price of diesel fuel. Estimated life is at least 5 years based on the vinyl, one sign supply website stated "Tested minimum outdoor life of 6 years". However, it's too early to say what else might go wrong.

I'm sure this method is not for everyone, I don't have to worry much about impact resistance, just wind damage mostly. During Hurricane Frances September '04, I laid the panels flat on the ground and they survived quite well with no water intrusion.

[sandovalch]

Is there any chance you could post a picture? Thanks.

[fishfarm]

I don't currently own a digital camera but probably should. I'll try to borrow or buy one in the next couple of days.

[ghurd]

Real usable watts is different than rated watts.

Your panels are right on track for the output I would expect.

Maybe ArmourAll or other protectorant would extend the life of the vinyl?

G-

[picmacmillan]

yes fishfarm, i would be real interested in seeing the vinyl you used to cover the cells....i am up to 5 panels now, i will probably get 7 or so from 5 pounds....i am having a bit of a time with putting the ribbon back on some of them, it won'tstick.... any ideas?.......pickster....

[pyrocasto]

I would very much like to see some pictures too. If at all possable, put them on up perty please.

[fishfarm]

Here's a couple pics I took today:

[fishfarm]

Thanks for the input. I agree the manufacturer rating is not "real world". i understand they use a "flash test" to measure output, which probably prevents any temperature loss.

The ArmourAll is a good idea. I have some STP Son of a Gun I'll try.

[fishfarm]

Let me know what other info or other pictures you would like on the vinyl. As for soldering the cells, I wound up essentially double-soldering them; the first pass was to place a spot of solder on the pads, then a second pass to solder the ribbons to the pads. My thought was that the solder connection was probably the most critical part of the assembly so I spent more time on that. I used a silver-bearing solder from Radio Shack and a 140 watt soldering gun.

Here's a front and back of a string if that helps:

[pyrocasto]

After you vinyl the cell rows, what do you put over top the entire piece of plywood? Or do you even cover the top?

I never though about it, but when the vinyl starts to break down, you would kinda be screwed because it would still be stuck to the solar cells and you couldnt get it off. I'm thinking the vinyl should last a good 10 years(hopefully) though.

[fishfarm]

1) Nothing on top. The strings went straight on the frame and stapled down. I have considered adding 4'x8' sheets of thin acrylic (say 1/10") for additional protection and may yet if it looks like I need it. The acrylic I looked at has a 92% light transmission efficiency and I don't want to lose another 8% if I can help it.

2) I agree. I considered the eventual degradation of the vinyl in the estimate of the array lifetime. When or how this will occur is TBD. If it does become opaque, I'm hoping the vendor can tell me the best way to remove it. I did note on their website that surfactants and plasticizers can cause adhesive failure. I'm also hoping the failure will only be on the exposed top of the cells, leaving the underside ok.

[ghurd]

Just remembered... A friend had an old Jeep with vinyl windows that had yellowed very badly.  They make a stuff to clear them up again. It worked. Don't know what they call it. An aftermarket jeep place would know. Maybe its not the same.

G-