Question of the Week
Answer: I am pleased to provide you with information on livestock water freeze protection. Appropriate technologies do exist for keeping livestock water tanks open during cold weather. These include passive systems of storing solar energy or geothermal heat and using it to keep water above freezing. ATTRA suggests the following ideas:
1. Pump water into a large enclosed storage tank at a higher elevation. You should insulate the tank in some way, bury it, or mound dirt up around it. If the tank is exposed, paint it black to absorb the sun’s heat during the day. From the storage tank, run a buried line to supply the watering tanks by gravity and control this flow with a float valve. You may want to use a thermostatically controlled float valve that opens when temperatures drop below a certain point. You can position some of these valves so that they direct water around the outside of the watering tank to keep water open for stock. You can also pump water into the storage tank during the day, so that it will continuously trickle into the watering tank at night and on cloudy days. The watering tank will need an overflow drain-field.
2. If a storage tank is not an option, you can use a solar pumping system to fill the watering tank directly during the day. Make a small hole that allows the tank to drain slowly at night to keep water moving.
3. You can use large heavy-equipment tires as watering tanks. These help keep water open since they are black and absorb heat from the sun. They are also flexible enough not to crack if freezing occurs. These tires are often free for the taking and they are very tough and can take abuse from animals.
4. Much of the heat loss from a watering tank occurs at the surface of the water. You can reduce this heat loss considerably by placing an insulated cover over a large part of the surface area of the tank. Provide openings around the edge where animals can drink. You can also insulate the sides of watering tanks with insulation material, sawdust, or wood chips. Partially burying a watering tank, or berming it with earth, takes advantage of the ground’s warmth to prevent freezing.
5. Another way to make use of underground warmth is to install a culvert with a sealed bottom under the tank. You can circulate water from the culvert into the tank with a separate small-wattage solar-powered pump. This system requires a battery bank to allow for night use. You’ll need to put the batteries in a non-freezing area, perhaps on a platform above the water level in the culvert.
6. You can use a special in-tank propane heater to keep water from freezing.
7. Another way to use propane is to run a ¼ inch copper tube from the regulator into the water tank and crack the propane valve open slightly, just enough to elicit small bubbles from the tube. The bubbling action will keep water open at the spot it emerges from the water. A propane tank will last over a month if used in this manner.
Energy-Free Livestock Waterers
A variation on item 5 above is to use an insulated livestock waterer in the manner suggested by Alberta Agriculture. They have tested low-input energy-free livestock water delivery and heating technology that relies on geothermal heat to keep water open during cold weather, as low as -15° F. For a report on the construction, use, and maintenance of the energy-free system, see:
Energy Free Water Fountains, Alberta Agriculture and Food (PDF/273 KB)
Energy-free waters can be purchased from MiraFount.
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