The article is mostly taking about passive solutions. But yeah, geothermal heat pumps are just refrigerant based A/C systems with the condensor (or evaporator,

The article is mostly taking about passive solutions. But yeah, geothermal heat pumps are just refrigerant based A/C systems with the condensor (or evaporator, or fancy reversible valve to switch back and forth for heat or cool) stuck in the ground.