geothermal

As I wrote last time, we hope to control the sow's behavior in her pen in our new farrowing house by varying the temperature of the floor.  We started by installing plastic pipes on urethane insulation under the concrete.  As you can see in the first two pictures fourteen of these "loops" were installed under what would be the center of the pen, from about four feet inward from the gutter end to eight and one half feet, a total span of about four and one half feet.  This is where we expect the sow to nest up and have her piglets, with the guard rails adjacent and the water cup and dunging area in the four feet next to the gutter end, and the feed bowl and piglet creep area in the three feet at the pen's front.  See the pen pictures in the last post.  Through these fourteen loops of pipe we will pump cool water in summer and warm water in winter.  You can also see in these pipe pictures that we have installed a curving set of four pipes right near the very front of the pen.  These pipes will circulate warm water all year long, to tempt the piglets away from the sow to the warmer parts of the floor.

We have dug a geothermal supply trench west of the barn to a depth of twelve feet(see picture)  This was deep enough so that we got water in the bottom even in the very dry fall of 2012.  This trench was dug out five hundred feet from the barn at twelve feet and then those five supply pipes were folded back and run back toward the barn at a depth of eight feet.  This gives about 1000 feet of total collection area.  Now ground temperature at those depths is going to hover around 45 or 50 degrees winter and summer.  By pumping water through those pipes, we can chill it to that temperature in summer and then pump it through the cooling grid of under floor pipes to bring the sow a cooling effect and make her comfortable enough to want to lay quietly with her piglets.  Then in winter, plans are to run warm water through the same pipes to increase her comfort in that area while we keep the remainder of the building quite cool.  For now plans are to use a gas fired boiler to provide hot water for the floor under the sow in winter and under the piglets year around.  Very soon we plan to tie a good solar thermal panel into that system to minimize the amount of gas needed.

Meanwhile, in winter, we will continue to use the geo thermal trench, but now we will use the temperature which may be at 50 or 55 degrees at start of winter, to preheat the intake ventilation air so that the heating needs in the building will be minimized.  We do not have this part of the system settled in our minds yet and it will be some time before we have it in use.  The final picture is to give an idea of how we have tied the new building into the existing barn, getting a good second use out of the barn for a utilities and prep area, plus bedding and feed storage.