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.

Steam generator systems including tubesheet assemblies, such as for use in nuclear reactor systems, and associated devices and methods are described herein. A representative steam generator system can be installed in a nuclear reactor vessel positioned to house a primary coolant. The steam generator system can include a tubesheet assembly defining a plenum and comprising a tubesheet and a flexible connection portion coupling the tubesheet to the reactor vessel. The tubesheet can include a plurality of perforations fluidly coupled to the plenum. The steam generator system can further comprise a plurality of heat transfer tubes fluidly coupled to the perforations and configured to receive a flow of a secondary coolant. The connection portion can be more flexible than the tubesheet and the reactor vessel to reduce stresses on the tubesheet and the connections (e.g., tube-to-tubesheet (TTS) welds) between the tubes and the tubesheet during operation of the nuclear reactor system.

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.

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.

An aroma diffuser using an aroma capsule is disclosed to include a hollow housing including a first opening on a top side thereof, a second opening on a bottom side thereof and an integrated holder member downwardly inwardly extended from a top side thereof and defining therein a holding chamber facing toward the first opening, a heat conduction device mounted in the holding chamber, and a heating element mounted at a bottom side of the heat conduction device and kept in contact with the heat conduction device. Thus, an aroma capsule can be placed in the holding chamber and heated by the heating element to release fragrant vapor. After the aroma contained in the aroma capsule is used up, the aroma capsule can be replaced conveniently and rapidly.

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.

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.

The disclosed apparatus and control system produces a single, on demand, energetic gaseous working fluid from any heat source. Working fluid in a liquid phase is released into a heat exchange tube in the form of very fine droplets or atomized mist, where it is rapidly heated to its gaseous phase. The gaseous working fluid can continue to absorb heat before exiting the heat exchange tube to perform work. The disclosed system controls the release of working fluid into the heat exchange tube and/or the heat energy to which the tube is exposed, resulting in a flow of energetic gaseous working fluid that can be quickly adjusted in response to changing conditions without a large pressure vessel.

A control method for operating a heat recovery steam generator having a flue gas channel in which an evaporator, having at least two evaporator heating surfaces arranged successively in the flue gas channel and at least one intermediate heating surface arranged between the evaporator heating surfaces, is provided, the method including determining a characteristic value characteristic of the heat absorption in the evaporator for the evaporator heating surfaces, additionally determining for the at least one intermediate heating surface, an additional characteristic value for the heat absorption of the intermediate heating surface, and subtracting this additional characteristic value from the characteristic value characteristic of the heat absorption in the evaporator.

A control method for operating a heat recovery steam generator having a flue gas channel in which an evaporator, having at least two evaporator heating surfaces arranged successively in the flue gas channel and at least one intermediate heating surface arranged between the evaporator heating surfaces, is provided, the method including determining a characteristic value characteristic of the heat absorption in the evaporator for the evaporator heating surfaces, additionally determining for the at least one intermediate heating surface, an additional characteristic value for the heat absorption of the intermediate heating surface, and subtracting this additional characteristic value from the characteristic value characteristic of the heat absorption in the evaporator.