Heat buffer comprising at least mechanically coupled wall parts, wherein each of the wall parts comprises a substantially plate-like body; a liquid throughflow circuit incorporated in the body; one or more hydraulic couplings accessible from the outer side of the wall part for discharge and supply of liquid to the liquid throughflow circuit and configured for coupling to hydraulic couplings of a similar device; and is coupled at a mutual angle about a substantially vertical axis to a similar wall part, wherein the mechanically coupled devices are connected such that they enclose one space and wherein the heat buffer also comprises a floor and/or cover part for closing the enclosed space on an upper and/or underside.

A helical pile including a heat exchanger is described. The pile is formed from a lead section and one or more extension sections. The interior of the lead and extension sections are hollow and form a heat exchanger cavity. At the lower end of the lead section is a helical blade. Rotation of the lead section causes the helical blade to screw into the ground, thus pulling the lead section downward. Extension sections are added to the lead section and the pile is rotated until it is installed to a desired depth. The pile includes an inflow tube extending a predetermined distance into the heat exchanger cavity and an outflow port connected with the heat exchanger cavity. In operation, a heat carrying fluid is pumped into the inflow tube from a heat source or sink, for example, a heat pump for a building heating and cooling system. The fluid exits the tube at a point near the bottom of the heat exchanger cavity. The fluid flows upward through the heat exchange cavity and exchanges heat with the surrounding soil. The fluid flows out through the outflow port and back to the heat source or sink.

A geothermal heat utilization system includes a heat source well facility, a heat source device having a refrigeration cycle including a compressor, a condenser, an expanded portion, and an evaporator, a primary refrigerant circuit that is connected to a first unit which is one of the condenser and the evaporator of the heat source device, heat exchange being able to be performed between the first unit and the well-side pipe, a secondary refrigerant circuit that is connected to a second unit which is the other of the condenser and the evaporator of the heat source device, heat exchange being able to be performed between the second unit and a load, and a mode switching unit that switches between a cold heat storage operation mode in which the primary refrigerant circuit is connected to the evaporator and the secondary refrigerant circuit is connected to the condenser and a cold heat discharge operation mode in which the primary refrigerant circuit is connected to the condenser and the secondary refrigerant circuit is connected to the evaporator.

A thermal storage subsystem may include at least a first storage reservoir disposed at least partially under ground configured to contain a thermal storage liquid at a storage pressure that is greater than atmospheric pressure. A liquid passage may have an inlet connectable to a thermal storage liquid source and configured to convey the thermal storage liquid to the liquid reservoir. A first heat exchanger may be provided in the liquid inlet passage and may be in fluid communication between the first compression stage and the accumulator, whereby thermal energy can be transferred from a compressed gas stream exiting a gas compressor/expander subsystem to the thermal storage liquid.

A heat transfer system includes a conduit having open first and second ends, first and second thermal exchange segments disposed in-between and in fluid communication with the ends, and a means for adding fluid to the first end. The first thermal exchange segment is disposed underneath and in thermal communication with the ground, a body of water, or other location with a different temperature. The first and second ends are arranged above all other section of conduit and relative to one another so that they are communicating vessels and a change in fluid level in one changes the fluid level in the other. The means for adding fluid to the first end of the conduit causes fluid to flow freely from the first end to the second end and fluid level to rise in the second overcoming any hydrostatic pressure in the system without a pump disposed along the conduit.

The present disclosure relates to a method for storing excess energy from at least one energy producing source, as thermal energy, using an existing geologic formation. First and second storage zones formed in a geologic region may be used to store high temperature and medium high temperature brine. When excess energy is available from the energy producing source, a quantity of the medium high temperature brine is withdrawn and heated using the energy supplied by the energy source to form a first new quantity of high temperature brine, which is then injected back into the first storage zone. This forces a quantity of medium high temperature brine present in the first storage zone into the second storage zone, to maintain a desired quantity of high temperature brine in the first storage zone and a desired quantity of medium high temperature brine in the second storage zone.

The present invention relates to devices and systems for collecting and storage of solar energy, wherein the system for storing and retrieving captured temperature based energy comprising: one or more thermal collectors (5, 60), an energy carrier (29), a piping system (3, 7, 34, 35, 36), pumping device for controlling the flow of the energy carrier (29), and one or more ground thermal storage systems (30).

The present disclosure relates to a system for storing and time shifting at least one of excess electrical power from an electrical power grid, excess electrical power from the power plant itself, or heat from a heat generating source, in the form of pressure and heat, for future use in assisting with a production of electricity. An oxy-combustion furnace is powered by a combustible fuel source, plus excess electricity, during a charge operation to heat a reservoir system containing a quantity of a thermal storage medium. During a discharge operation, a discharge subsystem has a heat exchanger which receives heated CO.sub.2 from the reservoir system and uses this to heat a quantity of high-pressure, supercritical CO.sub.2 (sCO.sub.2) to form very-high-temperature, high-pressure sCO.sub.2 at a first output thereof. The very-high-temperature, high-pressure sCO.sub.2 is used to drive a Brayton-cycle turbine, which generates electricity at a first output thereof for transmission to a power grid. The Brayton-cycle turbine also outputs a quantity of sCO.sub.2 which is reduced in temperature and pressure to a heat recuperator subsystem. The heat recuperator subsystem circulates the sCO.sub.2 and re-heats and re-pressurizes the sCO.sub.2 before feeding it back to the heat exchanger to be even further reheated, and then output to the Brayton-cycle turbine as a new quantity of very-high-temperature, high-pressure sCO.sub.2, to assist in powering the Brayton-cycle turbine.

The present invention relates to a thermal conductive cylinder installed with U-type core piping and loop piping for being installed within natural thermal storage body or artificial thermal storage body; wherein the piping segments of fluid inlet terminal and/or outlet terminal of the U-type core piping and loop piping are directly made of thermal insulating material, or thermal insulating structure is installed between the inlet terminal and the outlet terminal; so as to prevent thermal energy loss between adjacent piping segments on the same side when thermal conductive fluid with temperature difference passing through.

A thermal storage subsystem may include at least a first storage reservoir configured to contain a thermal storage liquid at a storage pressure that is greater than atmospheric pressure. A liquid passage may have an inlet connectable to a thermal storage liquid source and configured to convey the thermal storage liquid to the liquid reservoir. A first heat exchanger may be provided in the liquid inlet passage and may be in fluid communication between the first compression stage and the accumulator, whereby thermal energy can be transferred from a compressed gas stream exiting a gas compressor/expander subsystem to the thermal storage liquid.