Need dehumidifier solution for shipping container, but no AC power

Discussion in 'Homesteading Questions' started by HaggHomesteader, Sep 4, 2017.

  1. HaggHomesteader

    HaggHomesteader Member

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    I have a 40' HC shipping container on my property, but no AC power available yet, and probably won't for a year or two. I've got various items stored in the container, including tools, but also things like some books and paper. I bought a couple of buckets of DampRid (crystals) that may help bring down the humidity, but I'd like to get a better solution that pulls the moisture out of the air and keeps it low, with maybe a monthly service cycle. I was hoping to find a few battery powered dehumidifiers, but no dice--they take too much power and require AC.

    Does anyone know of a good solution for dehumidifying a shipping container without the use of DampRid or salts? By the way, the container is supposed to be air-tight (advertised as such), but I noticed it has a few tiny vents in the upper corners.

    Thanks,
    Chris
     
  2. Fire-Man

    Fire-Man Well-Known Member Supporter

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    I have several, and the only one I have had moisture problems with is one that I had set in a shaded area which the ground under/around it stays moist for a while after a rain, BUT its not a big problem. The other ones are out in the sun most all day and the ground around it dries quick after a rain(well drained). One of those even has clothes hanging on racks, books, lots of things in it. BUT, I open them several times a week----on sunny days I leave one of the doors open all day. We do not have hardly any snow here and not a lot of days that stay below freezing during the day. They do make a solar vent that runs just off the solar panel----no sun---it does not run---cloudy----does not run. That would work/help some.
     
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  3. HaggHomesteader

    HaggHomesteader Member

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    Thanks, Fire-Man. I'm glad to hear you don't have moisture problems. I hope the goes for me. I'll look into the solar vent. This was helpful.

    If there are any other suggestions from anyone, I'm still open to hear...
    Thanks!
     
  4. Wolf mom

    Wolf mom Well-Known Member

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    I had a 40 footer and had 2 wind turbines installed in the roof. In the winter, in a light snow area (6000 ft elevation) I'd cover them with doubled plastic bags and taped closed.
    I used half for hay storage. The other side was used for junque storage - christmas ornaments, etc. I also raised it off the ground onto railroad ties. Never any moisture problems.
     
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  5. HaggHomesteader

    HaggHomesteader Member

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    Cool! Well, I'm glad you didn't have the humidity problems, either. I also have mine on railroad ties, which might help.
     
  6. Fire-Man

    Fire-Man Well-Known Member Supporter

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    This one is at a good price----I bought one but have never used it. Keep in mind I do not have a problem with the ones in the sun----the one that stays in the shade----You Guessed it----solar would Not work in the shade. Put them in the sun in my opinion. You can cool seal/white to cut down on inside temp as well as open the door when its sunny---if you can.
    http://www.ebay.com/itm/Solar-Power...461940?hash=item35f2e68b74:g:gp8AAOSw4HVWDX1u
     
  7. MichaelZ

    MichaelZ Well-Known Member Supporter

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    If you can get enough ice in metal containers that have sufficient surface area, it will act as a dehumidifier, condensing moisture. Just make sure to have catch pans underneath which you will have to empty periodically, unless you can run a drain hose down a drain. And with this, keep the doors and windows sealed air tight to keep humidity out. It would take quite a bit of ice, so make a deal with an ice supplier.

    Note that I have never tried this except for the fact that our toilet tank condenses out all kinds of moisture on humid days due to its cold water inside. Also, I know that a dehumidifier is nothing more than refrigerated coils condensing out water.
     
  8. HaggHomesteader

    HaggHomesteader Member

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    Thanks, MichaelZ! I didn't know that a fan would alone (w/ solar panel) would dehumidify, but I support that it runs when it's hot and sunny. My container is in the full sun. So, how did you install the fan, if you don't mind me asking.
     
  9. HaggHomesteader

    HaggHomesteader Member

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    Interesting idea. Well, since I don't live at the property, I'm hoping the leave whatever system I have in place there for 30 days at a time. Great idea, but this may rule out ice in my case. Thanks for suggesting, though.
     
  10. hunter63

    hunter63 Well-Known Member

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    It won't.....
    "Dehumidify" is a process that pulls moisture out of the air by mechanical means...is actually a small A/C unit...and requires current of some kind.

    Fans will "circulate" outside air...be it dry or moist....and will require cutting in vents in the metal, mounting the fan unit, as well as solar panels and controls....for both voltage battery and humidity setting....you don't want to circulate wet air ...like a rainy day....especially if you are not there.

    Gonna be tough to get from here to there, easily....no easy cheap answer.
     
  11. Fire-Man

    Fire-Man Well-Known Member Supporter

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    That is why I felt this above linked solar fan would work----it does not have a battery---only runs if the sun is shinning on the solar panel. It can do a air exchange on sunny days. But as I mentioned above---I never installed mine----hasn't been needed because I open them a few days out the week and leave them open all day some days.
     
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  12. Fire-Man

    Fire-Man Well-Known Member Supporter

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    Not MichaelZ, but being you quoted my post I will reply. A fan exchanging humid air inside with warm dryer air from outside should help a lot with inside humidity. Like I stated above. I bought one, but have never installed it. It has not been needed in my situation because I do open mine often and leave them open on sunny days-----Not every sunny day---maybe a few days during the week.
     
  13. fishhead

    fishhead Well-Known Member Supporter

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    My first thought was of using salt too. Either bags of feed salt or inorganic fertilizer will pull some of the moisture out of the air inside the container. Will it be enough? That I can't say but I'll bet that some researcher can tell you how much water salt or fertilizer can absorb. You might be able to dry the salt by heating it with solar heat on a really low humidity day. Maybe put it in a small greenhouse of some sort.
     
  14. MichaelZ

    MichaelZ Well-Known Member Supporter

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    Note that exchanging cool air for warm outside air may actually increase your moisture if the warm air is humid. Warmer air holds more moisture. But given you are not using this space, here is what you can do:
    When you have a very dry spring day with dewpoint of 45F or less, bring in much outside air as possible. Then seal it up air tight - meaning all cracks taped tight. If you can seal it up sufficiently when it is dry, it could stay dry all summer.
     
  15. Fire-Man

    Fire-Man Well-Known Member Supporter

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    I agree--another reason I manually open and close mine---so I do not pull or allow humid air into them---best to leave them closed. Another thought----maybe add a humidity switch to a solar fan---if the humidity is not below the set adjustment---it want come on!! I like that!!
     
  16. hunter63

    hunter63 Well-Known Member

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    Temperature differential will effect condensation formation on a non-insulated space,....especially metal.
    I had prepared a 55 gal off site cache of emergency supplies......
    Then sleeping bags, sealed up long term freezed dried foods ...etc.

    Sealed in the airtight 55 drum (I thought(?) ......after a year drum had rust and condensate in the inside.
    Supplies that were sealed in plastic bags came thru through fine.....some tools stored showed rust.
    Do you have a way to protect your stored supplies in bags, and totes?
     
  17. manfred

    manfred Well-Known Member

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    I've had a 20 footer for about 15 years. In e, Okla. I set it on several squarerocks that keep it a few inches off the ground.
    Never had any problem with mold at all. my guns are stored there and no rust.
     
  18. HaggHomesteader

    HaggHomesteader Member

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    Lots of great feedback. Thanks a lot. I'm heartened that I may not have a very big humidity problem on my hands, based on some of the feedback, though the 55 gallon drum didn't keep moisture out very well (and no, Hunter63, I don't have anything stored in bags, but looks like a good idea for paper items and some tools). I think my plan is to put in a humidity indicator and monitor that along with a couple buckets of DampRid. I'll monitor and as necessary add more DampRid and perhaps move on to big buckets with rock salt.

    I'll give it a try and let you know how I fair over the winter. Good experiment! Thanks to everyone that posted!