I didn't run today

Four of my grandkids were visiting last night and half of today. In the afternoon, my wife and I spent a couple of hours walking in the hot sun looking at exhibits at a Conservation show. One exhibit I enjoyed was about using a heat pump to heat as well as cool ones house. The horizontal pipes for this only have to be down about 10 feet to be in the zone of the ground that is at a constant temperature of, if I remember the temperature, 51 degrees (F). Or, they can drill a well about 150 feet deep and put pipes in there instead of in horizontal trenches.