Ground tubes to condition thermal heat pumps

[MattM]

Has anyone ever mated the idea of air going through ground-buried tubes with thermal heat pumps?  It should be relatively easy to mount 'heat pumps' over a grate built into the slab it rest on.  That way its always drawing air from a ground temperature enhanced environment.  I realize the longer the tube, the greater the resistance to airflow.  But its much easier to fix that resistance than putting in 8000 feet of water lines to use ground temperature for thermal heat pumps.

[joestue]

You still need a long pipe to get the surface area you need to move the heat.

The usual figure is 200 feet per ton, 6" diameter bore hole filled with cement and a 1" pex loop.

Apparently the pex is a significant limitation and folks are running 2 loops in the same 6" borehole.

Yes i have read about folks burying 4" corrugated plastic pipe and blowing air through it, through a coil in the ground..

Horizontal fields are a compromise between the lower cost but slso lower average ground temperature.

[MattM]

Seems like it would work for a window shaker better than a ground-based box mount.  Getting air properly to the exchanger's fins is most practical in a linear system.  The typical mounted system seems to be a box.  Almost would need a cooling tower design to make it work properly.