Abstract: The present disclosure provides conduits with modified interior surfaces that increase the surface area of the interior surface of the conduit to provide the conduit with improved thermal energy exchange with the wall of the conduit. The modified interior surfaces can also be configured to reduce friction flow on the fluid passing therethrough.

Abstract: A method and apparatus for efficiently extracting geothermal energy from a subterranean thermal reservoir through a wellbore where the heat exchange fluid is introduced at a slower velocity than the velocity at which the fluid is extracted. The method and apparatus further comprises a region void of cement between the outer wall of a casing and the inner wall of the wellbore, such that thermally conductive material can be injected therein.

Abstract: A method and apparatus for extracting geothermal energy from a subterranean thermal reservoir through a wellbore where the heat exchange fluid is introduced at a slower velocity than the velocity at which the fluid is extracted. The method and apparatus further comprises a gas zone near the top of the wellbore to maintain the thermal energy of the heat exchange fluid. In one embodiment, a portion of the casing of the wellbore can directly contact the subterranean environment. Alternatively, a thermally conductive wall comprising a thermally conductive material can surround a portion of the casing of the wellbore. Further, the inner and/or outer surface of the pipes and conduits of the disclosed method and apparatus can include modified surface features that influence the flow and/or thermal conductivity of the heat exchange fluid.

Abstract: An apparatus and method for desalinating fluids produced or returning from a subterranean formation using pressure from a subterranean formation. Fluid from a formation is sent to a liquid/liquid separator for separating water from the fluid and then to a reverse osmosis unit, one or more of which are configured to operate from pressure delivered from a subterranean formation. The liquid/liquid separator operates under pressure and includes oleophilic materials for extracting oil from the formation fluid.

Abstract: A method and apparatus for efficiently extracting geothermal energy from a subterranean thermal reservoir through a wellbore where the heat exchange fluid is introduced at a slower velocity than the velocity at which the fluid is extracted. The method and apparatus further comprises a gas zone near the top of the wellbore to reduce heat losses of the heat exchange fluid. A portion of the casing of the wellbore can directly contact the subterranean environment for improved thermal conductivity. Alternatively, a thermally conductive wall comprising a thermally conductive material can surround a potion of the casing of the wellbore. Further, the inner and/or outer surface of the pipes and conduits of the disclosed method and apparatus can include features that enhance the surface areas for improved heat transfer efficiency.