System for energy storage including a heat transfer fluid tank

Abstract

The invention is directed to a system for energy storage including a heat transfer fluid (HTF) tank containing a HTF such as water; a chemical combustion reactor that is at least partially filled with a metal and/or an oxide thereof, and that includes a gas inlet and a gas outlet; wherein the chemical combustion reactor is at least partially submerged in the HTF within the HTF tank.

1 . A system for energy storage comprising
 a heat transfer fluid (HTF) tank comprising a HTF such as water;   a chemical combustion reactor that is at least partially filled with a metal and/or an oxide thereof, and that comprises a gas inlet and a gas outlet;   
       wherein said chemical combustion reactor is at least partially submerged in the HTF within said HTF tank. 
     
     
         2 . The system according to  claim 1 , further comprising one or more heaters thermally connected to the chemical combustion reactor. 
     
     
         3 . The system according to  claim 2 , wherein the heater is connected to the gas inlet such that it can heat gas entering the chemical combustion reactor through said gas inlet. 
     
     
         4 . The system according to  claim 1 , wherein the chemical combustion reactor comprises a wall that is thermally connected to the HTF in which the chemical combustion reactor is submerged, and wherein said wall is a heat-conductivity switchable wall. 
     
     
         5 . The system according to  claim 1 , comprising a plurality of the chemical combustion reactors, wherein each chemical combustion reactor is at least partially submerged in the HTF within said HTF tank. 
     
     
         6 . The system according to  claim 1 , wherein the chemical combustion reactor has a cylinder shape or a helix shape. 
     
     
         7 . The system according to  claim 1 , further comprising a HTF storage tank that is in fluid connection to said HTF tank. 
     
     
         8 . The system according to  claim 1 , further comprising a reducing gas supply system. 
     
     
         9 . The system according to  claim 1 , wherein the metal comprises one or more metals selected from the group consisting of Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr and Sn. 
     
     
         10 . The system according to  claim 1 , wherein the chemical combustion reactor is a fixed bed chemical combustion reactor that is at least partially filled with one or more fixed beds comprising said metal and/or an oxide thereof 
     
     
         11 . The system according to  claim 10 , wherein the fixed bed comprising the metal is configured as a plurality of layers, within the chemical combustion reactor, and wherein one or more layers of said fixed bed is alternated with one or more heat insolating layers. 
     
     
         12 . The system according to  claim 10 , wherein the fixed bed has a porous structure of which the exposed surface is optionally essentially entirely covered with said metal. 
     
     
         13 . The system according to  claim 10 , further comprising cartridges comprising a supporting frame to support the fixed bed, said cartridges being stackable within the fixed bed chemical combustion reactor. 
     
     
         14 . A method for storing energy in a system in according to  claim 1 , said method comprising providing a reducing gas stream, leading said reducing gas stream into the chemical combustion reactor and allowing the reducing gas stream to react with a metal oxide in the chemical combustion reactor to reduce the metal oxide. 
     
     
         15 . A method for discharging energy from a system according to  claim 1 , said method comprising providing an oxidizing gas stream, and leading said oxidizing gas stream into the chemical combustion reactor and allowing the oxidizing gas stream to react with a metal in the chemical combustion reactor to oxidize the metal. 
     
     
         16 . The system according to  claim 2 , wherein said one or more heaters are located in the chemical combustion reactor such that they can locally heat part of the metal and/or an oxide thereof in the chemical combustion reactor. 
     
     
         17 . The system according to  claim 8 , wherein the reducing gas supply system is a hydrogen gas system. 
     
     
         18 . The system according to  claim 8 , wherein the reducing gas supply system is a water electrolyzing apparatus comprising a hydrogen gas outlet that is connected to the gas inlet of the chemical combustion reactor. 
     
     
         19 . The system according to  claim 18 , wherein the water electrolyzing apparatus comprising a hydrogen gas outlet is connected to a water inlet that is connected to the gas outlet of the chemical combustion reactor. 
     
     
         20 . The system according to  claim 1 , wherein the metal comprises one or more metals selected from the group consisting of Cu, Fe, Ni, Co, Mn, and ilmenite.