Thermal mass geo doesn’t require a hot spot or a deep well. All it needs is a stable temp at -4’ to -5’ elevation and enough room to put in a ditch 1’ wide and 80’-100’ long. It can also be done with a shallow bore hole (about 100’). It’s really amazing technology. In SE Tennessee where the soil temps are a constant 54F at -5’ you pass propylene glycol through either a coaxial absorber plate or about 300’ of coiled PEX tubing. The fluid is circulated through the field, then is then compressed twice using a heat pump, exchanging the energy pulled from the soil to freon then back to glycol for circulation in the floor. It works so well that you have to use a heat exchanger tank to keep from making steam. It’s very easy to get fluid temps in the 130F-150F range, perfect for radiant baseboard, radiant floor heat or even fan coils, although you lose a large percentage of efficiency by heating air. The run cycles of the compressors are very short, so not much electricity is used. To cool, you reverse the process using fan coil units to pull the heat out of the air through condensation. The system I’m putting in for my hangar this spring, coupled to existing LP fired radiant floor heat, runs in the neighborhood of 545% efficient for heating and 375% efficient for cooling. Pretty much blows everything else on the market away.
Here is some info from the first image in post #18. The dimensions are reduced but the size, in bytes, is of the full image:
Size: 1,674.99 KB (1,715,185 bytes)
Dimensions: 3,300px × 2,550px (scaled to 600px × 464px)