Abstract: A subterranean continuous loop heat exchanger is disclosed having a borehole including an entrance at a first end and an exit at a second end and a conduit for a fluid. A direction of fluid flow relative to the borehole is unidirectional, and a major length of the borehole is non-horizontal. The entrance and the exit are separated by a predetermined distance and a first thermal envelope at the entrance and a second thermal envelope at the exit are substantially independent. The conduit is positioned in at least a portion of the borehole and in operational connection to supply and return lines for connection to a ground sourced heat pump or to a heat exchanger system. Also disclosed are methods of constructing a subterranean continuous loop heat exchanger having at least one continuous borehole and a method of regulating a temperature in a structure with a system that includes the subterranean continuous loop heat exchanger.