Possible dessicant for solar cells

[Running Blue]

I was reading Pickster's post about his new Ebay cells and somewhere in the post was mentioned using a dessicant to absorb condensation.  The common dessicants that come in packaged electronics and the like do seem to have a limit as to how much moisture they can absorb before they have to be "cooked off" to remove the accumulated moisture.  This has obvious problems in a sealed panel once the dessicant is full.

I've used a product called Damp Rid for many years in my cellar that may be worth experimenting with.  Basically the stuff is left in the open and draws moisture from the air.  The "starter kit" comes with two plastic tubs, about the size of butter tubs, and one fits inside the other.  The inner tub has a perferated bottom and rests about an inch or two higher than the bottom of the outer tub.  The dessicant pellets are poured in the inner tub.  As the dessicant takes the humidity from the air it "drops" the excess moisture into the lower outer tub, which slowly fills with water and some dissolved dessicant.  After a month or so the collected moisture is discarded and the pellets are topped off again.

Seems like there could be a way to do something similar in a solar panel.  Someone mentioned a perferated tube filled with dessicant.  Maybe you could make a panel and seal it like a double pane window only with two aligned holes, one on top, one on the bottom.  The perf tube could fit through the holes, the top could be stoppered and the bottom could be screened to keep the dessicant in but let moisture drain.  After a period of time the tube could be opened, topped off and stoppered again.

You can buy just a refill carton of Damp Rid since you wouldn't need the tubs.  Seems like I got it at WalMart.  I'm not sure how environmentally friendly this stuff is or for sure what it's made of.  You may want to use a drain line to keep this stuff off your roof and collect it in a jug down below.  Seems like it might work.

There's always another project!

-Blue

[Ungrounded Lightning Rod]

The common dessicants that come in packaged electronics and the like do seem to have a limit as to how much moisture they can absorb before they have to be "cooked off" to remove the accumulated moisture.  This has obvious problems in a sealed panel once the dessicant is full.

If the panel is really sealed no more moisture will get in.  B-)

[Jeff7]

True, however, if moisture is present when it's sealed, that might condense on the glass front. I'm experimenting with filling the panel with helium, which will hopefully flush out any moist air. The prototype has been sealed up; I just need to wait for all the various adhesives/epoxies to dry and/or solidify, and I'll stick the thing in the sun, and begin my testing. I'll try to get some pics of it posted to my website sometime in the not-too-distant future.

[picmacmillan]

i have left my panels out in the snow now, for 3 days and nights...there is no moisture in them that i can see....i think the panels have hit equilibrium with the outside air moisture....my concern now will be, how will they act in the spring when we have the thawing....i know my tools left out in the shed get damp from the moisture in the air in the spring....i hope like some posted that if they were filled where moisture wasn't a factor, the panels will be o.k....they are in fact sealed.......

 i have reservation about the above statement that if they were filled in a warm environment, they will stay dry....my theory is that moisture can get trapped between the two peices of glass, because hydrogen, and oxygen(H2o)=(water)...there will be a temperature difference between the glass and the outside air..

 i have seen this in practice while moose hunting and we build a makeshift house from clear plastic....

 we use 2 layers to trap the condensation produced between the two layers and it runs out the bottom which is left open...the condensation is created by the difference in temperature between the outside and the inside where the wood stove is running......the water will run between the sheets

 i am thinking that because there is a temperature difference and the panels are in fact going to be warmer than the  outside air that the panel will not be in equilibrium, therefore moisture will appear

 . i hope this theory is wrong,but due to others experience with moisture troubles, i would tend to think this will be the case...

 one more thing for my particular application is that, i will be in the far north of canada....the temperature swing there is very high...there could be frost in the morning and by the afternoon its 75-80 degrees farenheit, then back to freezing again at night or very cool...just my thoughts....pickster

[ghurd]

Breathing adds a lot of moisture to the air.  Try sleeping in the back of a truck with an aluminimum cap (shell?) when the temperature is around freezing.  Breath condenses on the roof.  It actually rains inside!

Sometimes I wonder why I go 'Up There' to your neck of the woods where its that cold in the summer.

G-

[Running Blue]

Okay granted, if the panel is sealed properly any additional condensation isn't an issue.  I'm just thinking out of the box, or maybe I should say out of the panel.  

Isn't heat buildup an efficieny issue in these panels?  What if two such dessicant tubes were installed on each side of the panel?  Would this also act as a ventilation source whereby heated air could escape instead of expanding?

-Blue

[Psycogeek]

I came up with a POSSIBLE moisture exchange idea

it would have to be tested.

they have polymers mostly used to keep plants water in the pot for weeks at a time.

it Expands as it attacts and holds water, and contracts to hard crystals when it goes dry.

Because the condensation eventually dries out , MABEY this stuff could hold some temporarily.

obviously if water is getting IN, that is bad, and the water can then get OUT.

so if that is happening, i would wonder how effective the polymers would be at tanking the water till it got hot again, and went back out.

Notes when using with plants:

using it with Plants, you have to Drench it, and it expands to 30X the size

then it does leech water to the plant slowly. but it takes a very long time SOAKING it to get it filled.

when the plants soil starts drying out, there is a POINT where the crystals start keeping water from the plant , instead of providing for it.

the Smaller it is ground, the quicker it soaks up water.

but it still takes TIME to get enough water IN it, to have it be an assett to the plant.  otherwize the crystals would kill the plant instead of water it.

because of its properties, i would wonder if it would be more effective for large quantities of water, than the harder silicoln things that hold much less water.

its size would determine speed , smaller faster

the ammount of water in it would determine how well it captured or releaced water

it MIGHT be self rechargable, under the idea, of what got in can get out, when the sun bakes it.

[Psycogeek]

Links

http://www.cbsnews.com/stories/2000/07/07/earlyshow/saturday/main213116.shtml

http://water-absorbing-crystals.com/water_absorbing_polymers.html

this stuff is CHEAP too, get it at wallymart for 10$ a container or less.

grind it wet or dry, to change its size.