Geothermal Heating, Cooling & Hot Water
From https://www.hydrodelta.com/:
Anyone who has a refrigerator
or air conditioner is already familiar with the operation of a geothermal heat pump. Contrary to common belief, cold is not something that is produced, but is a condition that results when heat has been removed. If you remember your high school physics class, you know that heat is produced by a molecular motion. All substances are made up of tiny molecules that are in a state of rapid motion. As the temperature of a substance is increased, the molecular motion increases, and as the temperature decreases, the molecular motion decreases. Molecules move faster on a warm surface than on a cool surface. Heat will flow from a warm substance to a cool substance. Reminder: Second Law of Thermodynamics.