Thoughts: How to keep water unfrozen in winter outside

Please describe what you mean by "keeping their water from freezing" means. Does that mean a 24/7 supply from some well or other building that needs to flow all the time, or does it mean keeping a stock tank from freezing?

I have built a number of water systems to draw water from under a frozen lake at -40 that require little or no power (except for the pump).

Icarus

 

Could you hook up a compressor air tank and add bubbles to to the water, if the water is moving it will not freeze
Change the air tank when you change the water
Also I have no idea what size of air tank you would need

 

It seems that horses winter water needs increase due their
diet changing to dried hay/grass/grain. I never knew that.

Here's an interesting discussion and in-use analysis of a
DIY solar stock tank heater.

Some other ideas from "out in the field" here.

 

Even an aerated tank will freeze if it is cold enough. For 0F. I would build a box around the water tank, and either spray foam it or put pink or blue board around it, to perhaps R-15, build an insulated cover so only as much of the surface area is exposed as possible, including perhaps a bubble cover and protect the whole thing from the wind. Then if you add water every day or two, there should be enough thermal mass to keep it from freezing.

We have a wood fired hot tub, where the stove sits in the tub (a simple galvanized stock tank) that sits on the ice in the winter. Even at -10F it only loses ~15-20 degrees in 20 hours. (From 105f to ~85F) The key is to keep the wind off it.

 

How are you going to get the horses to drink from a pit?

 

if there is a water supply, they have hydrants that shut off 4' down, below freezing, but the standing water in the trough would freeze and need to be changed.

 

How about adding something to the water? How much Ethyl alcohol would have to be added to lower the freezing point? Perhaps the amount of Ethyl alcohol would be too high for the horses to tolerate. There are other substances as well. Just not sure the concentrations required to move the freezing point of the water low enough for your needs. =)

 

it could be, if the water is moving fast enough, it might not freeze. depends on extended temps i s'pose.

 

Maybe you ned two pits: one for the water, and one for uh...'horse fertiliser' that will decompose and possibly generate enough heat to keep the water from freezing. There might even be some methane to flare off and heat the water.

 

Having spent many a cold morning feeding and watering the livestock. Here are my thoughts-
1) The most fundamental issue is to keep the wind from blowing on it or by it. Specifically, ensure that the water is in a corner.....but still easily accessible to the human. (The less #$$%^%$# you tromp through, the better.)
2) Basic farm reality - The lower to the ground the water is, the faster it gets dirty. You don't want the solution to create more problems than the original setup.
3) Insure that the basic water tank makes it easy to remove the ice on top. My experience is that on nasty cold days, you always make an extra check of the animals (since warm water and a frozen horse is disaster). One of the critical checks is to make sure that the water is available. It's much easier to remove the ice covering on a water holder with slope to it rather than a pure cylinder.
4) There are many water heaters, dispensers, etc. in farm catalogs that would be the next thing to do beyond the above simple measures. No sense in reinventing those devices when it's cheaper to buy them than build them. I'm pretty sure the desire is for something simple that minimizes the problem with the simplest measures possible.

 

How deep is the frost line?

 

Meanwhlle back at the ranch. Let say you have 100 gallons of water in a tank. The weight of that 100 gal= ~800lbs. holds ~800 btus per degree f above freezing. So all one need to is to limit the heat loss from the container to less than that of the btu capacity of that water.

Calculate how many gallons you replace a day and at what temperature it is going in at. Lets say the water comes in @ 55F, a sort normal well temperature, and you put in 30 gallons per day. (I have know idea of how much water a horse uses!) that 30 gallons of water would have ~ 5500 btus to lose before it freezes. (23 degrees Delta T 23*30gallons*8lbs=5520btus. So all one need to is protect the water from losing that many btus.

You can do a simple heat loss calc, using say R 10 under the tank (floor) R-20 in the walls, R-20 on top (less any R-0 where horses can drink) and do the calcs.

For those that may not know, the U value of a structure is the inverse of the R-value. It is a quantifiable measure of heat loss (or gain) through a medium, like foam insulation.

U*Delta T= BTU/Hour/ft sq.

Walls Say U= .05*1*32=1.6 btu/sqf/hourt at 0F
Celiling .04U= .04*1*32=1.28
Floor .04U= .04*1*32=1.28

So lets assume the walls are 2'X6 for the long side, 2'X2' for the short side so you would have a total of 32 ft sq of wall, 12 ft sq of floor and "ceiling".

Heat loss for the sides would be 32*1.6=51 btu/hour @ 0F
Celing/floor 12*1.28*2=30.72 btu/hour @0f for a total btu loss of ~81 btu/hour.

So take the 5500 btus of water, and lose 81/hour over 24 hours (1944 btus/day) and you can easily see that the tank won't freeze. Add in some loss through the drinking hole, and do a guess for the btus lost by removing the water that the horses drink and there you have it.

Like we say in the Solar biz, conservation is everything. Add foam to the outside of the box up to ~R-20-30 keep it out of the wind and it will never freeze.

Icarus

Please check my arithmetic, as a quasi dyslexic I am very prone to math errors, as people who know me know. Also, I also have guessed a bit on the U values so they may not be 100% accurate, but should be close enough to prevent the tank from freezing.

 

I've seen people float large pieces of thick Styrofoam on top of stock tanks, to reduce air contact, and keeping the water liquid.
Of course, you would be reusing that styrofoam, not buying new (icky!!) - and, your horses would have to be the sort that don't see chunks of styro on top of their water as tub toys, to be chewed and thrown on the floor.

 

Barring everything else, a simple RV water heater (propane fired) could thermo-siphon tank water pretty simply. Problem would be getting the controls to fire it at a much lower temp, but that too is solveable.

Icarus