Amazing Solar Water Trough

Some time ago I found a story about a solar water trough project, and wanted to try it out.  Because we live in an area (Eastern Idaho) where we get winter temperatures down to -25 degrees, I knew I would have to change the design a little to compensate for the very low temperatures.  I made some changes and added about 4 inches of solid foam insulation under, over, and all around the galvanized metal water trough which is inside the plywood case.  Behind the clear corrugated poly-carbonate greenhouse panels in the front, is the front of the metal trough which is painted black to help absorb some heat from the sun.  The top is screwed down, and has a square hole on top where the cow drinks from.  The hole is a covered with an insulated top at night.  I have a water trough heater inside but have not had to use it.  I am amazed at how well the trough works.  Even at -25 degrees I have only found a slight skim of ice on top of the water's surface.  To warm the water up enough to last through the day without freezing, it only requires some added well water.  

Brian Drinking From the Solar Water Trough

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