The invention provides a heat-storage medium conveying system for a solar-thermal power plant. The system includes a high-level tank subsystem including a high-level tank used to store the heat-storage medium. The system further includes a heat-storage medium transport subsystem. The high-level tank subsystem is connected with the heat-storage medium transport subsystem. The heat-storage medium transport subsystem includes a low-level tank. A mounting height of the low-level tank is lower than that of the high-level tank. A volume of the low-level tank is smaller than a volume of the high-level tank. The heat-storage medium can enter the low-level tank from the high-level tank partially or completely by its own gravity. The low-level tank is provided with a conveying pump, and the heat-storage medium is pumped out of the low-level tank through the conveying pump. The invention solves the problems such as construction cost, operation and maintenance cost brought about by using the vertical long-shaft submerged molten salt pump, while avoiding the potential safety hazards in the design of large and small tanks or high-level and low-level tanks.

Various embodiments include a thermal storage system for storing energy in a graphite thermal storage structure and a thermal shutter assembly configured to control the transmission of heat from the graphite thermal storage structure to a thermal energy receiver, such as a heat exchanger or material processing crucible. A thermal storage block, which may be made of graphite, may be isolated by insulation except for the thermal shutter assembly. Energy may be stored in the graphite thermal storage block by applying energy to the block to raise its temperature to maximum operation temperature. Stored energy may then be harvested in a controlled manner by a control system actuating the thermal shutter to expose the thermal energy receiver to thermal radiation.

A rotating heat pipe is used for temperature control of electric motors and generators and other rotating heat generating assemblies to ensure their proper operation. The heat pipe is integral with the shaft, and unlike conventional devices, incorporates a solid-liquid phase change material as the heat transfer/transport material. In addition, it comprises a scraped surface heat exchange mechanism at the heat dissipation region to allow for high cooling rates as required. This scraped surface mechanism is preferentially driven by a magnetic coupling to eliminate issues related to leaks of the heat transfer material.

An energy storage system converts variable renewable electricity (VRE) to continuous heat at over 1000° C. Intermittent electrical energy heats a solid medium. Heat from the solid medium is delivered continuously on demand. An array of bricks incorporating internal radiation cavities is directly heated by thermal radiation. The cavities facilitate rapid, uniform heating via reradiation. Heat delivery via flowing gas establishes a thermocline which maintains high outlet temperature throughout discharge. Gas flows through structured pathways within the array, delivering heat which may be used for processes including calcination, hydrogen electrolysis, steam generation, and thermal power generation and cogeneration. Groups of thermal storage arrays may be controlled and operated at high temperatures without thermal runaway via deep-discharge sequencing. Forecast-based control enables continuous, year-round heat supply using current and advance information of weather and VRE availability. High-voltage DC power conversion and distribution circuitry improves the efficiency of VRE power transfer into the system.

A heat pump system and a cooling/heating system using same, the heat pump system being able to prevent the occurrence of a vortex in a process in which fluid flows into a heat storage tank, and to supply and maintain constant-temperature cooling and heating. The heat pump system according to the present invention includes: an indoor unit which functions as a condenser during heating and functions as an evaporator during cooling; an outdoor unit which functions as an evaporator during heating and functions as a condenser during cooling; a heating medium for heat exchange; and a heat storage tank in which the heating medium for cold/hot water is stored.

A device is disclosed for the storage and transfer of solar thermal energy which includes a casing having a irradiation opening for the entry of incident solar radiation in a irradiation region of the casing. a bed of fluidizable solid particles received within the casing, and a plurality of reflecting and radiating surfaces arranged within the irradiation region and configured to convey the solar radiation entering through the irradiation opening, after multiple reflections, on the bed of particles.

A heat exchanger is provided capable of exchanging heat received from a concentrated solar power plant via heat exchanging pipes and conducting the heat via patterns of flexible heat conducting cables into heat storing solids. The heat exchanger is further capable of exchanging heat stored by heat storing solids via the patterns of flexible heat conducting cables to heat exchanging pipes for use by a heat consumer. The heat exchanger has a charging and a discharging speed of a heat exchanger is about 50 kW/m.sup.3 or at least 50 kW/m.sup.3.

Heat exchangers for thermal storage systems include a valve that can direct process fluid passing through the heat exchanger through supplemental heat exchanger tubing based on a temperature of the process fluid. The supplemental heat exchanger tubing can be located in areas where ice formation can occur during freezing of the storage fluid of the thermal storage system, but apart from the standard flow path for the heat exchanger. The valve can be a thermally-actuated valve. The thermally actuated valve can be set to divert flow of the process fluid to the supplemental tubing when the process fluid is at or above a melting temperature of the storage fluid. Methods can include selectively flowing process fluid through supplemental heat exchange tubing when it is at a temperature greater than the melting point of a storage material.

The disclosure relates to particle heaters for heating solid particles to store electrical energy as thermal energy. Thermal energy storage directly 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 particle heater is an integral part of an electro-thermal energy storage system, as it enables the conversion of electrical energy into thermal energy. As described herein, particle heater designs are described that provide efficient heating of solid particles in an efficient and compact configuration to achieve high energy density and low cost.

A method for assembling a thermal battery. The method including: arranging a plurality of tubes into a cylindrical shape; connecting the plurality of tubes to each other; attaching a first plate to a first end of the connected plurality of tubes into corresponding holes in the first plate; providing an initiation device to the first end of each of the plurality of tubes; filling each of the plurality of tubes from a second end with an exothermic material; assembling thermal battery components inside the connected plurality of tubes; connecting terminal wires to the thermal battery components; and connecting the second end of the connected plurality to a second plate.