High-density, high-temperature thermal energy storage and retrieval

Abstract

A thermal energy storage (TES) system that uses an elemental material (e.g., elemental sulfur) as an energy storage material is disclosed. The energy storage material is separately stored from a heat transfer fluid. For example, the energy storage material can be sealed within one or more corrosion-resistant containers that are further contained within an outer shell. A heat transfer fluid flows through the shell via an inlet and an outlet, over and around the containers. A TES system may include an energy source that receives thermal energy intermittently, and a steam generator.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
         1 . A thermal energy storage component, comprising:
 an outer shell having an inlet and an outlet to accommodate a flow of a heat transfer fluid from the inlet to the outlet; and   a plurality of thermally conductive containers disposed in the outer shell, wherein each container contains only an elemental material comprising an element selected from the group of elements consisting of sulfur, mercury, selenium, hydrogen, nitrogen, and oxygen;   wherein the thermal energy storage component is configured to selectively: (i) transfer thermal energy from the heat transfer fluid to the elemental material for thermal energy storage, and (ii) transfer thermal energy from the elemental material to the heat transfer fluid to recover stored thermal energy.   
     
     
         2 . The thermal energy storage component of  claim 1 , wherein the elemental material transitions between two or more allotropic forms during the transfer of thermal energy between the heat transfer fluid and the elemental material. 
     
     
         3 . The thermal energy storage component of  claim 1 , wherein the elemental material consists of sulfur. 
     
     
         4 . The thermal energy storage component of  claim 1 , wherein the elemental material consists of sulfur, mercury, or selenium, and further wherein the elemental material is in a liquid form and a solid form during at least a portion of the transfer of thermal energy. 
     
     
         5 . The thermal energy storage component of  claim 1 , wherein the elemental material consists of sulfur, mercury, or selenium, and further wherein the elemental material is in a liquid form and a gaseous form during at least a portion of the transfer of thermal energy. 
     
     
         6 . The thermal energy storage component of  claim 1 , wherein the plurality of containers are sealed. 
     
     
         7 . The thermal energy storage component of  claim 1 , wherein the plurality of containers are cylinders. 
     
     
         8 . The thermal energy storage component of  claim 1 , wherein the plurality of containers are spheres. 
     
     
         9 . The thermal energy storage component of  claim 1 , wherein the plurality of containers are formed of a material selected from the group consisting of stainless steel, iron, carbon steel, carbon, aluminum, nickel, tantalum, molybdenum, platinum, and any combination thereof. 
     
     
         10 . The thermal energy storage component of  claim 1 , wherein the heat transfer fluid is selected from the group consisting of a molten salt, a liquid metal, and a synthetic organic heat transfer fluid. 
     
     
         11 . An indirect thermal energy storage system configured for use with a thermal energy source comprising:
 (a) a thermal energy storage component comprising a shell having an inlet and an outlet, and a plurality of sealed thermally conductive containers disposed within the shell, wherein each sealed thermally conductive container contains only an elemental material comprising an element selected from the group of elements consisting of sulfur, mercury, selenium, hydrogen, nitrogen, and oxygen;   (b) a thermal energy user; and   (c) a fluidic control system operable to selectively circulate a heat transfer fluid between the thermal energy source, the thermal energy storage component, and the thermal energy user to selectively: (i) transport thermal energy from the thermal energy source to the thermal energy user, (ii) transport thermal energy from the thermal energy source to the thermal energy storage component, and (iii) transport thermal energy from the thermal energy storage component to the thermal energy user.   
     
     
         12 . The indirect thermal energy storage system of  claim 11 , wherein the plurality of containers are cylindrical. 
     
     
         13 . The indirect thermal energy storage system of  claim 11 , wherein the plurality of containers are spherical. 
     
     
         14 . The indirect thermal energy storage system of  claim 11 , wherein the thermal energy user comprises a steam boiler. 
     
     
         15 . The indirect thermal energy storage system of  claim 14 , wherein the elemental material consists of sulfur. 
     
     
         16 . A thermal energy storage component, comprising:
 a sealed outer shell having containing an elemental fluid selected from the group of elements consisting of sulfur, mercury, selenium, hydrogen, nitrogen, and oxygen; and   a plurality of tubes having an inlet and an outlet to accommodate a flow of a heat transfer fluid from the inlet to the outlet;   wherein the thermal energy storage component is configured to selectively: (i) transfer thermal energy from the heat transfer fluid to the elemental material for thermal energy storage, and (ii) transfer thermal energy from the elemental material to the heat transfer fluid to recover stored thermal energy.   
     
     
         17 . The thermal energy storage component of  claim 16 , wherein the elemental material consists of sulfur. 
     
     
         18 . The thermal energy storage component of  claim 16 , wherein the elemental material consists of sulfur, mercury, or selenium, and further wherein the elemental material is in a liquid form and a solid form during at least a portion of the transfer of thermal energy. 
     
     
         19 . The thermal energy storage component of  claim 16 , wherein the elemental material consists of sulfur, mercury, or selenium, and further wherein the elemental material is in a liquid form and a gaseous form during at least a portion of the transfer of thermal energy. 
     
     
         20 . The thermal energy storage component of  claim 16 , wherein the plurality of containers are formed of a material selected from the group consisting of stainless steel, iron, carbon steel, carbon, aluminum, nickel, tantalum, molybdenum, and any combination thereof 
     
     
         21 . The thermal energy storage component of  claim 16 , wherein the heat transfer fluid is selected from the group consisting of a molten salt, a liquid metal, and a synthetic organic heat transfer fluid.