A kit for use with a recirculating cooling system includes a bag. The bag includes a first wall, a second wall opposite the first wall, and a side wall defining a reservoir configured to retain a fluid therein. A first port is defined through the first wall and a second port is defined through the side wall or the second wall. The bag is configured to maximize a temperature differential between a fluid proximate the first port and a fluid proximate the second port. Further, the bag is collapsible.

A thermal-storage container used in thermal systems to exchange heat by fluid flow though phase-changing material disposed inside the thermal-storage container, including a thermal-storage container housing, a fluid inlet and a fluid outlet, and one or more capsules containing the phase-change material, and defining a plurality of passages configured to direct the flow of the fluid at different portions inside the housing, wherein an actual fluid flow length from the fluid inlet to the fluid outlet is longer than a direct length measured between the fluid inlet and the fluid outlet through all sections through which the fluid flows. Related apparatus and methods are also described.

A thermal-storage container used in a thermal-storage system to exchange heat by fluid flow though phase-changing material disposed inside the thermal-storage container, including a thermal-storage container housing, a fluid inlet and a fluid outlet, and one or more capsules containing the phase-change material, wherein the housing is shaped as an elongate container, a ratio of length to width of the housing is between 2 and 20. Related apparatus and methods are also described.

The invention relates to a thermal energy storage with at least one thermal energy storage volume. The thermal energy storage comprises at least one primary borehole extending from ground level to a first predetermined depth in a rock body; at least one set of secondary boreholes located around the at least one primary borehole; and at least an upper and a lower fracture plane extending in a radial and/or oblique plane from the at least one primary borehole towards adjacent secondary boreholes. At least one fracture plane permits a hydraulic flow between at least one of the secondary boreholes and the primary borehole. Each thermal energy storage volume is defined by one set of secondary boreholes and its upper and lower fracture planes. The set of secondary boreholes diverge away from the at least one primary borehole at each fractured plane level, without intersecting the at least one primary borehole.

The present disclosure describes heat exchangers for converting thermal energy stored in solid particles to electricity. Electro-thermal energy storage converts off-peak electricity into heat for thermal energy storage, which may be converted back to electricity, for example during peak-hour power generation. The heat exchanger for converting thermal energy stored in solid particles to electricity enables the conversion of thermal energy into electrical energy for redistribution to the grid. In some embodiments, pressurized fluidized-bed heat exchangers may achieve efficient conversion of thermal energy to electricity by providing direct contact of the solid particles with a gas stream.

A diffuser is provided for use in a thermal storage tank. The diffuser includes a fluid inlet to receive a flow of liquid into the diffuser, and a fluid outlet to discharge the flow of liquid out of the diffuser into an internal volume of the thermal storage tank. A flow circuit extends between the fluid inlet and the fluid outlet. A plurality of flow sections are sequentially arranged along the flow circuit. Each one of the plurality of flow sections defines a cross-sectional flow area for the flow of liquid. The cross-sectional flow area within any one of the plurality of flow sections is greater than the cross-sectional flow area within any of the plurality of flow sections arranged upstream of said one of the plurality of flow sections.

A diffuser for a water heater fill tubes having a tube wall with an outside diameter. The diffuser includes an elongated flexible diffuser body for positioning at the outlet end of the fill tube. The diffuser body has a sealing end for sealing with an outside surface of the fill tube wall closest to the inlet end of the fill tube, and an open end for positioning at an end closest to the outlet end of the fill tube. The open end has a diameter larger than an outside diameter of the tube wall, thereby creating an diffuser water outlet opening between the diffuser body and the tube wall for redirecting radial water flow emanating from the fill tube water outlet opening(s) toward the diffuser outlet opening. A fill tube assembly for a water heater, a water heater, and a method for heating water are also disclosed.

A diffuser for a water heater fill tubes having a tube wall with an outside diameter. The diffuser includes an elongated flexible diffuser body for positioning at the outlet end of the fill tube. The diffuser body has a sealing end for sealing with an outside surface of the fill tube wall closest to the inlet end of the fill tube, and an open end for positioning at an end closest to the outlet end of the fill tube. The open end has a diameter larger than an outside diameter of the tube wall, thereby creating an diffuser water outlet opening between the diffuser body and the tube wall for redirecting radial water flow emanating from the fill tube water outlet opening(s) toward the diffuser outlet opening. A fill tube assembly for a water heater, a water heater, and a method for heating water are also disclosed.

A stratified storage tank for a heat transfer fluid for a heating and/or cooling system, having at least one connection chamber which has at least one connection for connecting a line for supplying and/or discharging heat transfer fluid into and/or out of the stratified storage tank, at least one buffer chamber arranged beneath and/or above the at least one connection chamber, at least one first barrier element having a first, peripherally arranged opening, and at least one second barrier element having at least one second opening and being arranged between the at least one first barrier element and the at least one buffer chamber. Fluidic communication is provided between the at least one connection chamber and the at least one buffer chamber by the first opening and the at least one second opening, and the at least one second opening is arranged centrally relative to the buffer chamber.

Methods are provided for controlling thermal energy storage in a thermal energy management system that may operate in response to a variable or high transient heat load. Thermal energy management systems are also provided for controlling thermal energy storage that may operate in response to a variable or high transient heat load.