Thermal energy storage systems and methods

Abstract

A thermal energy storage apparatus is disclosed. The thermal energy storage apparatus has a phase change medium, an inner header having at least one inner feed port, and an outer header having at least one outer feed port and fluidically coupled to the inner header. The inner header and the outer header are configured to be substantially immersed in the phase change medium. Related methods of constructing and controlling a thermal energy storage system are also disclosed. A thermal energy power system utilizing a thermal energy storage apparatus is further disclosed, as is a heat exchanger for the thermal energy storage system.

1 . A thermal energy storage apparatus, comprising:
 a phase change medium;   an inner header having at least one inner feed port;   an outer header having at least one outer feed port and fluidically coupled to the inner header; and   wherein the inner header and the outer header are configured to be substantially immersed in the phase change medium.   
     
     
         2 . The thermal energy storage apparatus of  claim 1 , wherein the phase change medium is selected from the group consisting of a salt, a salt mixture, a eutectic salt mixture, lithium nitrate, potassium nitrate, sodium nitrate, sodium nitrite, calcium nitrate, lithium carbonate, potassium carbonate, sodium carbonate, rubidium carbonate, magnesium carbonate, lithium hydroxide, lithium fluoride, beryllium fluoride, potassium fluoride, sodium fluoride, calcium sulfate, barium sulfate, lithium sulfate, lithium chloride, potassium chloride, sodium chloride, iron chloride, tin chloride, and zinc chloride. 
     
     
         3 . The thermal energy storage apparatus of  claim 1 , wherein the inner header is centered within the outer header. 
     
     
         4 . The thermal energy storage apparatus of  claim 1 , wherein the inner header and the outer header lie on substantially the same plane. 
     
     
         5 . The thermal energy storage apparatus of  claim 1 , further comprising a collection header, and wherein the inner header is fluidically coupled to the outer header via the collection header. 
     
     
         6 . The thermal energy storage apparatus of  claim 5 , further comprising:
 one or more inner tubes coupled between the inner header and the collection header;   one or more outer tubes coupled between the outer header and the collection header; and   wherein the inner header is fluidically coupled to the outer header via the one or more inner tubes, the collection header, and the one or more outer tubes.   
     
     
         7 . The thermal energy storage apparatus of  claim 6 , further comprising one or more core heat tubes coupled to the inner header. 
     
     
         8 . The thermal energy storage apparatus of  claim 6 , wherein at least one of the one or more inner tubes further comprise a bypass valve configured to selectably create a hot spot in the phase change medium. 
     
     
         9 . The thermal energy storage apparatus of  claim 6 , further comprising a tankless structure configured to contain the phase change medium such that the inner header and the outer header are substantially immersed in the phase change medium. 
     
     
         10 . The thermal energy storage apparatus of  claim 9 , wherein the tankless structure comprises bricks. 
     
     
         11 . The thermal energy storage apparatus of  claim 10 , wherein the bricks comprise a material selected from the group consisting of firebrick, refractory material, castable refractories, refractory brick, mixtures of alumina (Al2O3), silica (SiO2), magnesia (MgO), zirconia (ZrO2), chromium oxide (Cr2O3), iron oxide (Fe2O3), calcium oxide (CaO), silicon carbide (SiC), carbon (C); metallic materials, plain carbon steels; alloy steels, manganese, silicon, silicon-manganese, nickel, nickel-chromium, molybdenum, nickel-molybdenum, chromium, chromium-molybdenum, chromium-molybdenum-cobalt, silicon-molybdenum, manganese-silicon-molybdenum, nickel-chromium-molybdenum, silicon-chromium-molybdenum, manganese-chromium-molybdenum, manganese-silicon-chromium-molybdenum, vanadium, chromium-vanadium, silicon-chromium-vanadium, manganese-silicon-chromium-vanadium, chromium-vanadium-molybdenum, manganese-silicon-chromium-vanadium-molybdenum, chromium-tungsten, chromium-tungsten-molybdenum, chromium-tungsten-vanadium, chromium-vanadium-tungsten-molybdenum, chromium-vanadium-tungsten-cobalt, chromium-vanadium-tungsten-molybdenum-cobalt; stainless steels, austenitic, ferritic, martensitic, duplex, precipitation-hardening, superaustenitic, superferritic; nickel alloys, nickel-chromium-iron, nickel-chromium-iron-aluminum, nickel-chromium-iron-aluminum-titanium, nickel-chromium-iron-aluminum-titanium-niobium, nickel-chromium-iron-cobalt-molybdenum, nickel-chromium-iron-niobium, nickel-chromium-iron-molybdenum-niobium, nickel-chromium-iron-molybdenum-niobium-titanium-aluminum, nickel-chromium-molybdenum-iron-tungsten, nickel-chromium-iron-molybdenum-copper-titanium, nickel-chromium-iron-molybdenum-titanium, nickel-iron-cobalt-aluminum-titanium-niobium, nickel-copper, nickel-copper-aluminum-titanium, nickel-molybdenum-chromium-iron, nickel-chromium-molybdenum-copper, nickel-chromium-molybdenum-iron-tungsten-copper, and nickel-chromium-molybdenum. 
     
     
         12 . The thermal energy storage apparatus of  claim 10 , further comprising at least one layer of insulation substantially surrounding the bricks. 
     
     
         13 . The thermal energy storage apparatus of  claim 12 , further comprising at least one band supporting the bricks. 
     
     
         14 . The thermal energy storage apparatus of  claim 10 , wherein the bricks are configured to have a cooling zone which encourages the phase change medium to solidify in at least a portion of gaps defined by the bricks. 
     
     
         15 . The thermal energy storage apparatus of  claim 9 , further comprising a base which supports the tankless structure. 
     
     
         16 . The thermal energy storage apparatus of  claim 15 , wherein the base comprises a material selected from the group consisting of earth, firebrick, refractory material, concrete, castable refractories, refractory concrete, refractory cement, insulating refractories, gunning mixes, ramming mixes, refractory plastics, refractory brick, mixtures of alumina (Al2O3), silica (SiO2), magnesia (MgO), zirconia (ZrO2), chromium oxide (Cr2O3), iron oxide (Fe2O3), calcium oxide (CaO), silicon carbide (SiC), carbon (C); metallic materials, carbon steels; alloy steels, manganese, silicon, silicon-manganese, nickel, nickel-chromium, molybdenum, nickel-molybdenum, chromium, chromium-molybdenum, chromium-molybdenum-cobalt, silicon-molybdenum, manganese-silicon-molybdenum, nickel-chromium-molybdenum, silicon-chromium-molybdenum, manganese-chromium-molybdenum, manganese-silicon-chromium-molybdenum, vanadium, chromium-vanadium, silicon-chromium-vanadium, manganese-silicon-chromium-vanadium, chromium-vanadium-molybdenum, manganese-silicon-chromium-vanadium-molybdenum, chromium-tungsten, chromium-tungsten-molybdenum, chromium-tungsten-vanadium, chromium-vanadium-tungsten-molybdenum, chromium-vanadium-tungsten-cobalt, chromium-vanadium-tungsten-molybdenum-cobalt; stainless steels, austenitic, ferritic, martensitic, duplex, precipitation-hardening, superaustenitic, superferritic; nickel alloys, nickel-chromium-iron, nickel-chromium-iron-aluminum, nickel-chromium-iron-aluminum-titanium, nickel-chromium-iron-aluminum-titanium-niobium, nickel-chromium-iron-cobalt-molybdenum, nickel-chromium-iron-niobium, nickel-chromium-iron-molybdenum-niobium, nickel-chromium-iron-molybdenum-niobium-titanium-aluminum, nickel-chromium-molybdenum-iron-tungsten, nickel-chromium-iron-molybdenum-copper-titanium, nickel-chromium-iron-molybdenum-titanium, nickel-iron-cobalt-aluminum-titanium-niobium, nickel-copper, nickel-copper-aluminum-titanium, nickel-molybdenum-chromium-iron, nickel-chromium-molybdenum-copper, nickel-chromium-molybdenum-iron-tungsten-copper, and nickel-chromium-molybdenum. 
     
     
         17 . The thermal energy storage apparatus of  claim 9 , wherein the outer header has a shape which substantially follows a shape defined by the tankless structure. 
     
     
         18 . The thermal energy storage apparatus of  claim 9 , wherein the tankless structure defines a horizontal cross-sectional shape which is selected from the group consisting of circular, oval, hexagonal, rectangular, and square. 
     
     
         19 . The thermal energy storage apparatus of  claim 1 , further comprising:
 at least one inner valve;   at least one outer valve;   an inner pipe which couples the inner valve to the inner feed port; and   an outer pipe which couples the outer valve to the outer feed port.   
     
     
         20 . The thermal energy storage apparatus of  claim 19 , wherein the inner pipe and the outer pipe enter the phase change medium substantially vertically. 
     
     
         21 . The thermal energy storage apparatus of  claim 19 , wherein the inner pipe and the outer pipe enter the phase change medium substantially horizontally. 
     
     
         22 . The thermal energy storage apparatus of  claim 1 , wherein the inner header and the outer header comprise material selected from the group consisting of plain carbon steels; alloy steels, manganese, silicon, silicon-manganese, nickel, nickel-chromium, molybdenum, nickel-molybdenum, chromium, chromium-molybdenum, chromium-molybdenum-cobalt, silicon-molybdenum, manganese-silicon-molybdenum, nickel-chromium-molybdenum, silicon-chromium-molybdenum, manganese-chromium-molybdenum, manganese-silicon-chromium-molybdenum, vanadium, chromium-vanadium, silicon-chromium-vanadium, manganese-silicon-chromium-vanadium, chromium-vanadium-molybdenum, manganese-silicon-chromium-vanadium-molybdenum, chromium-tungsten, chromium-tungsten-molybdenum, chromium-tungsten-vanadium, chromium-vanadium-tungsten-molybdenum, chromium-vanadium-tungsten-cobalt, chromium-vanadium-tungsten-molybdenum-cobalt; stainless steels, austenitic, ferritic, martensitic, duplex, precipitation-hardening, superaustenitic, superferritic; nickel alloys, nickel-chromium-iron, nickel-chromium-iron-aluminum, nickel-chromium-iron-aluminum-titanium, nickel-chromium-iron-aluminum-titanium-niobium, nickel-chromium-iron-cobalt-molybdenum, nickel-chromium-iron-niobium, nickel-chromium-iron-molybdenum-niobium, nickel-chromium-iron-molybdenum-niobium-titanium-aluminum, nickel-chromium-molybdenum-iron-tungsten, nickel-chromium-iron-molybdenum-copper-titanium, nickel-chromium-iron-molybdenum-titanium, nickel-iron-cobalt-aluminum-titanium-niobium, nickel-copper, nickel-copper-aluminum-titanium, nickel-molybdenum-chromium-iron, nickel-chromium-molybdenum-copper, nickel-chromium-molybdenum-iron-tungsten-copper, and nickel-chromium-molybdenum. 
     
     
         23 . A thermal energy power system, comprising:
 a) a phase change medium;   b) an inner header;   c) an outer header;   d) a collection header;   e) one or more inner tubes coupled between the inner header and the collection header;   f) one or more outer tubes coupled between the outer header and the collection header, wherein the inner header is fluidically coupled to the outer header via the one or more inner tubes, the collection header, and the one or more outer tubes;   g) a brick structure configured to contain the phase change medium such that the inner header and the outer header are substantially immersed in the phase change medium and wherein the bricks are configured to have a cooling zone which encourages the phase change medium to solidify in gaps defined by the bricks   h) a base which supports the brick structure;   i) a pump;   j) a renewable heat source;   k) a turbine plant; and   l) wherein the inner header and the outer header are reversibly connected in a closed loop with the pump, the renewable heat source, and the turbine plant and wherein the closed loop carries a heat transfer fluid.   
     
     
         24 . The thermal energy power system of  claim 23 , wherein the renewable heat source is selected from the group consisting of a solar parabolic mirror, a solar mirror farm, and a wind turbine. 
     
     
         25 . The thermal energy power system of  claim 23 , wherein the heat transfer fluid comprises oil. 
     
     
         26 . A method of constructing a thermal energy storage system, comprising:
 forming a base;   aligning at least one heat exchange system substantially over the base, the at least one heat exchange system comprising an inner header and an outer header;   dry-laying a brick wall substantially on the base to surround the at least one heat exchange system or an area where the at least one heat exchange system will be aligned; and   filling the area defined by the base and the brick wall with a phase change medium such that the phase change medium substantially covers the at least one heat exchange system.   
     
     
         27 . The method of  claim 26 , wherein forming the base further comprises forming the base on an insulator. 
     
     
         28 . The method of  claim 26 , wherein the brick wall comprises a material selected from the group consisting of firebrick and refractory brick. 
     
     
         29 . The method of  claim 26 , further comprising insulating the brick wall. 
     
     
         30 . The method of  claim 26 , further comprising banding the brick wall. 
     
     
         31 . The method of  claim 26 , further comprising:
 heating the phase change medium so that it transitions to a liquid phase and enters gaps defined by the dry-laid bricks of the brick wall; and   allowing the phase change medium to cool enough to solidify in at least a portion of the gaps in order to substantially seal the brick wall where it meets the phase change medium.   
     
     
         32 . A method of controlling a thermal energy storage system, comprising:
 a) when a renewable heat source is available:
 i) thermally and fluidically coupling the renewable heat source to an inner header of a heat exchange system which is substantially immersed in a phase change medium and which is further coupled to an outer header of the heat exchange system which is also substantially immersed in the phase change medium; and 
 ii) thermally and fluidically coupling the outer header to a turbine plant and then back to the renewable heat source in a closed-loop heating mode which provides a remaining renewable energy source heat to the turbine plant; and 
   b) when the renewable heat source is not available:
 i) thermally and fluidically coupling the renewable heat source to the outer header; and 
 ii) thermally and fluidically coupling the inner header to the turbine plant and then back to the renewable heat source in a closed-loop cooling mode which provides a stored heat to the turbine plant. 
   
     
     
         33 . A heat exchanger for a thermal energy storage system, comprising:
 an inner header having at least one inner feedport;   an outer header having at least one outer feedport and fluidically coupled to the inner header; and   wherein the inner and outer feedports are configured to enable a heat transfer fluid to reversibly flow from the inner header to the outer header when the inner header and the outer header are substantially immersed in a phase change medium.   
     
     
         34 . The heat exchanger of  claim 33 , wherein the inner header is centered within the outer header. 
     
     
         35 . The heat exchanger of  claim 33 , wherein the inner header and the outer header lie on substantially the same plane. 
     
     
         36 . The heat exchanger of  claim 33 , further comprising a collection header, and wherein the inner header is fluidically coupled to the outer header via the collection header. 
     
     
         37 . The heat exchanger of  claim 36 , further comprising:
 one or more inner tubes coupled between the inner header and the collection header;   one or more outer tubes coupled between the outer header and the collection header; and   wherein the inner header is fluidically coupled to the outer header via the one or more inner tubes, the collection header, and the one or more outer tubes.   
     
     
         38 . The heat exchanger of  claim 37 , further comprising one or more core heat tubes coupled to the inner header. 
     
     
         39 . The heat exchanger of  claim 37 , wherein at least one of the one or more inner tubes further comprises a bypass valve.