On a "Grand Design" program on ABC TV there was a house being built that used I think it was called a Heat pump or heat exchange to heat and cool the floor slab and to heat and cool air for the home.
The slab appeared to have pylons driven into the ground to conduct the stable temperature of the ground into the slab they also laid an underground pipe to bring air from the garden underground into the house, again using the mass of the earth to keep the air at a constant temperature.
Has anyone had any experience of these systems over here ?