Heat and cold storage tank with counterflow heat exchanger

Abstract

A heat storage and exchanger includes a first fluid conduit, a second fluid conduit, a heat exchanger, and a storage tank. The heat exchanger is configured to transfer heat between the first fluid conduit and the second fluid conduit. The storage tank is configured to receive a thermal storage medium. At least a section of the heat exchanger is arranged in the storage tank to enable a transfer of heat between the heat exchanger and the thermal storage medium.

What is claimed is: 
     
         1 - 45 . (canceled) 
     
     
         46 . A heat storage and exchanger comprising:
 a first fluid conduit and a second fluid conduit;   a heat exchanger configured to transfer heat between the first fluid conduit and the second fluid conduit; and   a storage tank configured to receive a thermal storage medium;   wherein at least a section of the heat exchanger is arranged in the storage tank to enable a transfer of heat between the heat exchanger and the thermal storage medium.   
     
     
         47 . The heat storage and exchanger according to  claim 46 , wherein the first fluid conduit and the second fluid conduit are in direct contact in the heat exchanger. 
     
     
         48 . The heat storage and exchanger according to  claim 47 , wherein the first fluid conduit and the second fluid conduit are in direct contact in the heat exchanger in a section of at least 0.5 m. 
     
     
         49 . The heat storage and exchanger according to  claim 46 , wherein:
 the second fluid conduit is thermally coupled to a solar system;   the first fluid conduit is thermally coupled to a cold side of a heat pump;   the storage tank is a cistern storage and is adapted for an underground arrangement; and   the storage tank has a volume for the thermal storage medium of at least 2 m 3 .   
     
     
         50 . The heat storage and exchanger according to  claim 46 , wherein:
 the heat exchanger comprises a double-pipe heat exchanger;   the first fluid conduit comprises an inner pipe of the double-pipe heat exchanger; and   the first fluid conduit is coupled to at least one of:
 a heat pump, and the cold side of a heat pump. 
   
     
     
         51 . The heat storage and exchanger according to  claim 46 , wherein:
 one of the first fluid conduit and the second fluid conduit is configured to pass through an upper surface of the thermal storage medium at least twice when the thermal storage medium is arranged in the storage tank;   said one of the first fluid conduit and the second fluid conduit passes through the storage tank at least twice in the uppermost fifth of its height extension;   the heat storage and exchanger comprises at least two additional heat exchangers, wherein the at least two additional heat exchangers are arranged at different heights in the storage tank.   
     
     
         52 . The heat storage and exchanger according to  claim 46 , wherein:
 the storage tank is configured as an ice storage;   the storage tank comprises at least one of:
 a circulation device configured to circulate the thermal storage medium in the storage tank; and 
 a pressure compensation vessel, wherein a gas volume of the pressure compensation vessel is at least 8% of a volume of the storage tank for the thermal storage medium; 
 wherein the thermal storage medium is arranged in the storage tank, wherein the thermal storage medium has a freezing point of at most −2°C. 
   
     
     
         53 . The heat storage and exchanger according to  claim 46 , wherein the storage tank comprises an upper lateral surface section and a lower lateral surface section, and wherein the upper lateral surface section comprises a stronger thermal insulation between the inner side and the outer side of the storage tank than the lower lateral surface section, wherein the lower region of the storage tank is thermally coupled to a surrounding soil. 
     
     
         54 . The heat storage and exchanger according to  claim 46 , wherein the thermal storage medium is arranged in the storage tank and wherein the thermal storage medium is configured to provide an electrolyte for an electrochemical cell, wherein the heat storage and exchanger is configured to provide the thermal storage medium of the electrochemical cell in a fluid-coupled manner. 
     
     
         55 . The heat storage and exchanger according to  claim 46 , wherein:
 a second section of the heat exchanger has no thermal contact with the thermal storage medium;   the second section of the heat exchanger has a thermal insulation to the thermal storage medium; and   the second section of the heat exchanger is arranged above a target filling height of the storage tank for the thermal storage medium.   
     
     
         56 . The heat storage and exchanger according to  claim 46 , further comprising at least one controller, wherein the at least one controller is configured to control a fluid flow through the first fluid conduit in dependence on a first parameter, wherein the first parameter is associated with at least one of:
 an availability of electrical power, and   an electrical power provided by a photovoltaic system.   
     
     
         57 . The heat storage and exchanger according to  claim 56 , wherein:
 the at least one controller is further configured to output a control signal for a heat pump in dependence on the first parameter, wherein the heat exchanger comprises a double-pipe heat exchanger, wherein the first fluid conduit comprises an inner pipe of the double-pipe heat exchanger, and wherein the first fluid conduit is coupled to the heat pump;   the first parameter is associated with the electrical power provided by the solar system, and the system comprises the solar system; and   the second fluid conduit is thermally coupled to a solar system.   
     
     
         58 . The heat storage and exchanger according to  claim 56 , further comprising a second heat storage and exchanger, wherein the second heat storage and exchanger comprises:
 a first fluid conduit and a second fluid conduit; and   a storage tank configured to receive a thermal storage medium;   wherein the second heat storage and exchanger is configured to enable a transfer of heat between the first fluid conduit and the thermal storage medium and between the second fluid conduit and the thermal storage medium;   wherein the at least one controller is configured to control a fluid flow through the first fluid conduit of the second heat storage and exchanger together with the fluid flow through the first fluid conduit of the heat storage and exchanger.   
     
     
         59 . The heat storage and exchanger according to  claim 58 , further comprising:
 a heat pump, wherein the at least one controller is further configured to output a control signal for the heat pump in dependence on the first parameter, wherein the heat exchanger comprises a double-pipe heat exchanger, wherein the first fluid conduit comprises an inner pipe of the double-pipe heat exchanger, and wherein the first fluid conduit is coupled to the heat pump;   wherein the fluid flow through the first fluid conduit of one of the heat storage and exchanger and the second heat storage and exchanger is configured to thermally couple that heat storage and exchanger to a cold side of the heat pump, and   the fluid flow through the first fluid conduit of the other heat storage and exchanger is configured to thermally couple the other heat storage and exchanger to a warm side of the heat pump; and   wherein the heat pump is configured to provide a power of at least 3 kW.   
     
     
         60 . A system comprising:
 a first heat storage and exchanger and a second heat storage and exchanger, wherein the first heat storage and exchanger comprises:   a first fluid conduit and a second fluid conduit;   a heat exchanger configured to transfer heat between the first fluid conduit and the second fluid conduit; and   a storage tank configured to receive a thermal storage medium, wherein:
 at least a section of the heat exchanger is arranged in the storage tank to enable a transfer of heat between the heat exchanger and the thermal storage medium; and 
 the first heat storage and exchanger has a volume for its thermal storage medium of at least 2 m 2  and is arranged at least partially underground; and 
   the second heat storage and exchanger comprises:
 a first fluid conduit and a second fluid conduit; and 
 a storage tank configured to receive a thermal storage medium, wherein:
 the second heat storage and exchanger is configured to enable a transfer of heat between the first fluid conduit and the thermal storage medium and between the second fluid conduit and the thermal storage medium; 
 a heat pump configured to provide a power of at least 5 kW, wherein:
 a fluid flow through the first fluid conduit of one of the first and second heat storage and exchangers is configured to thermally couple that heat storage and exchanger to a cold side of the heat pump; and 
 a fluid flow through the first fluid conduit of the other heat storage and exchanger is configured to thermally couple the other heat storage and exchanger to a warm side of the heat pump; and 
 a controller configured to control an operating state of the heat pump, the fluid flow through the first fluid conduit of the first heat storage, and the fluid flow through the first fluid conduit of the second heat storage together in dependence on a first parameter, wherein the first parameter is associated with an electrical power provided by a photovoltaic system; 
 wherein the second fluid conduit of at least one of the first heat storage and exchanger and the second heat storage and exchanger is coupled to a solar system. 
 
 
   
     
     
         61 . A method of operating a system comprising a heat storage and exchanger, wherein the heat storage and exchanger comprises:
 a first fluid conduit and a second fluid conduit, wherein the first fluid conduit is coupled to a heat pump;   a heat exchanger configured to transfer heat between the first fluid conduit and the second fluid conduit; and   a storage tank configured to receive a thermal storage medium;   wherein at least a section of the heat exchanger is arranged in the storage tank to enable a transfer of heat between the heat exchanger and the thermal storage medium;   wherein the method comprises at least two modes of operation, the method comprising:
 selectively executing one of the at least two modes of operation; 
 wherein the first mode of operation comprises:
 operating the heat pump at a first heat pump power; and 
 generating a fluid flow through the first fluid conduit to transfer heat between the heat pump and the thermal storage medium; and 
 wherein the second mode of operation comprises:
 operating the heat pump at a second heat pump power that is at most a quarter of the first heat pump power; and 
 generating a stronger fluid flow through the second fluid conduit than through the first fluid conduit to transfer heat via the second fluid conduit. 
 
 
   
     
     
         62 . The method of  claim 61 , wherein selectively executing one of the at least two modes of operation comprises automatically selecting between the first and second modes of operation based on a first parameter, wherein the first parameter is associated with an availability of electrical power. 
     
     
         63 . The method according to  claim 61 , wherein the second fluid conduit is thermally coupled to a solar system and the method further comprises:
 operating the system in the second mode of operation when the temperature of the solar system is below the freezing point of water while the temperature of the thermal storage medium of the heat storage and exchanger is above the freezing point of water;   wherein the method further comprises:
 controlling a flow of a fluid through at least one of the first fluid conduit and the second fluid conduit; 
 to reduce a temperature difference between a first fluid flowing out of one of the first fluid conduit and the second fluid conduit and a second fluid flowing into the other of the first fluid conduit and the second fluid conduit; and 
 to increase an additional temperature difference between the outflowing first fluid and the thermal storage medium. 
   
     
     
         64 . The method according to  claim 61 , wherein the heat storage and exchanger comprises a fluid coupling of the thermal storage medium to an external conduit, said external conduit being external with respect to the storage tank, and wherein the method further comprises:
 transporting electrolyte through said fluid coupling.   
     
     
         65 . The method according to  claim 61 , wherein the system further comprises a second heat storage and exchanger, wherein the second heat storage and exchanger comprises:
 a storage tank configured to receive a thermal storage medium; and   a first fluid conduit and a second fluid conduit;   wherein the second heat storage and exchanger is configured to enable a transfer of heat between the first fluid conduit and the thermal storage medium and between the second fluid conduit and the thermal storage medium;   wherein the method further comprises:
 performing the method steps having a relation to the heat storage and exchanger correspondingly on the second heat storage and exchanger; 
   wherein the first fluid conduit of one of the first and second heat storage and exchangers is coupled to a cold side of the heat pump; and   wherein the first fluid conduit of the other of the first and second heat storage and exchangers is coupled to a warm side of the heat pump.