Mini Swamp Cooler

In south Texas, we often have a significant amount of heat with which to deal.  One way to handle it when we get 21 days straight of 105+ degree weather is a swamp cooler.  It takes a little creativity to get it mounted, etc; but, here are the basics.

You will need:

Solar panel
Computer fan
Electrician’s tape/electrical twist caps
Water source
Expoxy/hot glue
Solar powered pond pump with hose
Plastic box for holding the sponge and fan
Small screen (small bit of scrap HW cloth is great)


Understand, this is not a strong breeze.  This is something that simply moves the air for small areas.  If you have a larger area, you will need multiples, or larger versions.


Swamp CoolerConnect the solar panel to the computer fan (or larger fan if you are using a larger solar panel).  You can see how to do it here.  If you have a three or four wire computer fan, you can still do the same thing, just use the positive and negative  wires and connect them to red and black respectively.  You can find the pin out for computer fans here.

You’ll need a bucket or something to hold your water.  I’d suggest something with a sealable lid that you can put a hose through (twice).  One is your out and one is your in.  You’ll see why in a moment.  This should be a reasonably sized container – a 20 gallon paint bucket with lid works great.

Figure out where it is that you want the cooler to be located.  Go take some measurements.  You want to be sure that you are within the range of your hose length.  You will run the hose up to where you intend to sit the fan and then back down to the bucket.  The outgoing hose needs to reach all the way to the bottom of the bucket to the pump, the incoming can be just inside the lid.  The purpose of the shorter hose is to return any residual water back to the bucket to be pumped back up through the sponge unit.

The unit holding the sponge will need a couple of things…one, a plastic box or something to attach the fan to.  Ensure the fan is oriented to pull air through the sponge, not push it.

You are going to cut two holes in the plastic box you are using to hold the fan and sponge.  One is going to be on the fan side, the other will be opposite the fan.  Cut it a bit smaller than the fan so you can either glue/epoxy it in place or punch holes in the plastic and use twist ties to hold it in place.  The side opposite the fan should have some hardware cloth to help hold the sponge in place and just to make me feel better.  There should be room above and below the sponge.  You can run wire all the way through from one side to the other to hold the fan, sponge and HW cloth all together, if you want.

The bottom of the box holding the sponge needs to have two holes in it that will allow your hose to enter and exit.  This is two pieces of hose, not one.  The hose that is bringing the water into the sponge “tank” needs to be actually inserted into the sponge or brought up over the top of the sponge to ensure the sponge gets completely doused with water.  Did I say sponge nearly enough in that sentence?  The excess that is not absorbed by the sponge will drain back down to the holding tank via the secondary hose.  So, the secondary hose needs to be a close to flush with the bottom of the sponge “tank” as possible.  Epoxy or hot glue works well to give a water tight seal.

The hose you will need will have to be rigged to your pump because most pond pumps are meant to be fountain type pumps.  It’s not that hard to find a decent hose and – again – epoxy works wonders to fill in any potential gaps.

Attach it all to the coop where you determined it was best.  Um, not to state the obvious – but, you really do want to be sure that your solar panels are on the south facing side, so plan accordingly.

You can make it smaller; but, when hitting serious heat, having a nice, large bucket sure helps.

Be sure that the pump you get is strong enough to get as high as you need it to go.  The small ones are generally sufficient and  don’t cost all that much.

If you want to get “fancy”, you could connect a water hose to the bucket controlled by a float valve….but, that’s mini-swamp cooler 2.0