The present invention relates to a system of heat exchange between a building (1) and the Earth's subsurface (5), comprising a closed loop with at least one pipe (9) installed in said subsurface (5) for heat exchange with subsurface (5), and connected by connecting pipes (4, 7) to at least one pipe (6) installed in said building (1) for heat exchange with building (1), the closed loop comprising a circulation pump (P) for circulating a fluid through said closed loop, and the fluid comprising capsules containing phase change materials.

The invention also relates to a method for cooling or heating a building (1) from the heat exchange system between a building (1) and the Earth's subsurface (5).

FIG. 1 to be published.

A method for extracting thermal energy in an underground high temperature area of a coalfield fire area, including: determining a thermal extraction target area by a natural potential method and a ground detecting borehole; using an injection borehole to send a gaseous thermal medium to an underground high temperature area of the thermal extraction target area; after the thermal exchange between the gaseous thermal medium and a high temperature coal rock mass, the gaseous thermal medium is extracted through an extraction borehole; continuously monitoring a natural potential of the thermal extraction target area; arranging a casing-type borehole thermal exchanger in a potential anomaly region to complete the thermal exchange between the high temperature coal rocks and a liquid thermal medium; stopping the thermal extraction operations when the temperatures of the extracted gaseous thermal medium and the liquid thermal medium reach 70 C. or below.

Fluid classes for use in energy recovery in well and geothermal environments for power production are disclosed. The fluids fall into the classes of fluids being capable of increasing thermodynamic efficiency of electricity and/or heat generation from a closed-loop geothermal system. Numerous methods are disclosed which exploit the thermodynamics of the fluids for optimum energy recovery.

A heat pump includes a first portion for evaporating a working fluid at a first pressure, for compressing the evaporated working fluid to a second, higher pressure, and for liquefying the compressed working fluid within a liquefier, and a second portion for compressing liquid working fluid to a third pressure, which is higher than the second pressure, for evaporating the working fluid compressed to the third pressure, for relaxing the evaporated working fluid to a pressure, which is lower than the third pressure, so as to generate electrical current, and for liquefying relaxed evaporated working fluid within the liquefier.

A system, composition and method for controlling fracture grown in the extraction of geothermal energy from an underground formation includes (i) introducing a first fracking fluid into an underground formation; (ii) introducing a second fracking fluid into the underground formation; wherein the specific gravity of the second fracking fluid is different from the specific gravity of the first fracturing fluid, thereby controlling the growth of at least one fracture in a downward direction, and wherein the fracking fluid in at least one of steps (i) or (ii) contains proppant particles having a thermal conductivity contrast of at least 5.

Systems and methods for generating and a controller for controlling generation of geothermal power in an organic Rankine cycle (ORC) operation to thereby supply electrical power to one or more of in-field operational equipment, a grid power structure, and an energy storage device. In an embodiment, during hydrocarbon production, a temperature of a flow of heated fluid from a source or working fluid may be determined. If the temperature is above a vaporous phase change threshold of the working fluid, heat exchanger valves may be opened to divert flow of heated fluid to heat exchangers to facilitate heat transfer from the flow of wellhead fluid to working fluid through the heat exchangers, thereby to cause the working fluid to change from a liquid to vapor, the vapor to cause a generator to generate electrical power via rotation of an expander.

A system and method of harvesting geothermal energy in a subterranean formation includes providing an injection wellbore that extends into the subterranean formation, positioning a plurality of selectively opening sleeves in the injection wellbore spaced apart the subterranean formation, providing at least one producing wellbore that extends into the subterranean formation in a predetermined location proximate to the injection wellbore, and fracturing the subterranean formation in a plurality of locations proximate to the plurality of selectively opening sleeves to enhance a fluid pathway between the injection wellbore and the at least one producing wellbore. Fluid is injected down the injection wellbore at a first temperature, and the fluid is produced from the at least one producing wellbore at a second temperature higher than said first temperature.

The field of the invention relates to systems and methods for exchanging heat from the degradation, decomposition, and chemical/biochemical transformation of municipal, industrial, and other types of waste. In one embodiment, a heat extraction system may include a closed-loop fluid circulation piping channeled throughout at least one heat extraction well oriented throughout a waste mass. The piping is fluidly coupled to a heat exchanger. A first circulation fluid is circulated through the closed-loop circulation piping into various depths of the waste mass to transfer thermal energy between said mass and said heat exchanger. In one embodiment, the transfer of thermal energy between the waste mass and the heat exchanger is used as alternative energy method and to control at least one of shear strength, compressibility, and hydraulic conductivity of the waste mass.

A geothermal well with communicating vessels includes: an internal piping transferring an inflow up to the level of the depth of the well; an inlet pump regulating the pressure of the fluid; an external piping, coaxial to the internal piping, with diameter allowing ascent of the fluid, from the distal end of the well upwards up to heat user device; a flange on the internal piping engaging a collar connected to the external piping through spacers; detection sensors transferring to a software the information on the oscillations of the pipings; an automatic safety valve to avoid overpressures; a driven regulation valve transferring to a software the information on the fluid pressure; and a dedicated software monitoring fluid circulation within the well, adapted to operate on the inlet pump, on the regulation valve and on a plurality of actuators, damping the oscillations and preventing microseisms.

A thermal-energy exchange and storage system has a borefield with a core zone and at least one capacity expansion zone. Each of the core zone and the at least one capacity expansion zone have a plurality of boreholes. The at least one capacity expansion zone is positioned outwards from and encircling the core zone and each additional capacity expansion zone is positioned outwards from and encircling the previous capacity expansion zone. A heat source is provided in fluid communication with a heat exchanger. An injection system circulates an operating fluid. The injection system has at least one U-tube installed within the plurality of boreholes and operating fluid is circulated between the at least one U-tube and the heat exchanger for transferring heat from the heat source. An extraction system is provided for extracting heat stored in the system for use in an infrastructure.