Heat-storage system and operating method of heat-storage system

Abstract

An operating method of a heat-storage system includes the steps of executing a first operating mode to supply heat to a first hydrogen storage alloy in a first tank, to cause movement of hydrogen from the first hydrogen storage alloy in the first tank to a second hydrogen storage alloy in a second tank, the second hydrogen storage alloy being different from the first hydrogen storage alloy in dissociation pressure characteristic with respect to an alloy temperature, and executing a second operating mode to supply cold of outside air to the first hydrogen storage alloy, to cause movement of hydrogen from the second hydrogen storage alloy in the second tank to the first hydrogen storage alloy in the first tank, in which the step of executing the first operating mode includes a step of storing a temperature generated in the second hydrogen storage alloy in a heat storage device.

1 . An operating method of a heat-storage system, comprising the steps of:
 executing a first operating mode to supply heat of a heat source to a first hydrogen storage alloy in a first tank, to cause movement of hydrogen from the first hydrogen storage alloy in the first tank to a second hydrogen storage alloy in a second tank, the second hydrogen storage alloy being different from the first hydrogen storage alloy in dissociation pressure characteristic with respect to an alloy temperature; and   executing a second operating mode to supply cold of outside air to the first hydrogen storage alloy, to cause movement of hydrogen from the second hydrogen storage alloy in the second tank to the first hydrogen storage alloy in the first tank, wherein   the step of executing the first operating mode includes a step of storing a temperature generated in the second hydrogen storage alloy in a heat storage device.   
     
     
         2 . The operating method of the heat-storage system according to  claim 1 , wherein the step of executing the first operating mode includes a step of operating a first gas pump that sends hydrogen from an inside of the first tank to the second tank when a dissociation pressure of the first hydrogen storage alloy is lower than a dissociation pressure of the second hydrogen storage alloy. 
     
     
         3 . The operating method of the heat-storage system according to  claim 1 , wherein the step of executing the second operating mode includes a step of operating a second gas pump that sends hydrogen from the second tank to the first tank when a dissociation pressure of the second hydrogen storage alloy is lower than a dissociation pressure of the first hydrogen storage alloy. 
     
     
         4 . The operating method of the heat-storage system according to  claim 1 , wherein the step of executing the first operating mode includes a step of supplying hydrogen generated in a water electrolysis apparatus to the first tank. 
     
     
         5 . The operating method of the heat-storage system according to  claim 1 , wherein the step of executing the first operating mode includes a step of supplying hydrogen generated in a water electrolysis apparatus to the second tank. 
     
     
         6 . The operating method of the heat-storage system according to  claim 1 , further comprising, after the step of executing the first operating mode, a step of supplying hydrogen from the first hydrogen storage alloy in the first tank to a fuel cell apparatus, and causing the fuel cell apparatus to perform power generation. 
     
     
         7 . The operating method of the heat-storage system according to  claim 6 , wherein after the step of supplying hydrogen from the first hydrogen storage alloy in the first tank to the fuel cell apparatus and causing the fuel cell apparatus to perform power generation, the step of executing the second operating mode is performed. 
     
     
         8 . The operating method of the heat-storage system according to  claim 1 , further comprising, after the step of executing the second operating mode, a step of supplying hydrogen from the second hydrogen storage alloy in the second tank to a fuel cell apparatus, and causing the fuel cell apparatus to perform power generation. 
     
     
         9 . The operating method of the heat-storage system according to  claim 1 , wherein either the step of executing the first operating mode or the step of executing the second operating mode includes a step of supplying hydrogen from the first hydrogen storage alloy in the first tank to a fuel cell apparatus and causing the fuel cell apparatus to perform power generation when a power failure occurs. 
     
     
         10 . The operating method of the heat-storage system according to  claim 1 , wherein either the step of executing the first operating mode or the step of executing the second operating mode includes a step of supplying hydrogen from the second hydrogen storage alloy in the second tank to a fuel cell apparatus and causing the fuel cell apparatus to perform power generation when a power failure occurs. 
     
     
         11 . The operation method of the heat-storage system according to  claim 1 , wherein a dissociation pressure of the first hydrogen storage alloy becomes higher than a dissociation pressure of the second hydrogen storage alloy upon receiving supply of heat higher than an outside air temperature at least in wintertime, and becomes lower than a dissociation pressure of the second hydrogen storage alloy upon receiving supply of cold of outside air. 
     
     
         12 . The operation method of the heat-storage system according to  claim 1 , further comprising
 having a solar power generation apparatus, a water electrolysis apparatus using electric power from the solar power generation apparatus, a fuel cell apparatus, and a hot water storage tank as the heat storage device, causing hydrogen generated in the water electrolysis apparatus to be stored in at least one of the first hydrogen storage alloy or the second hydrogen storage alloy, generating by the fuel cell apparatus electric power using hydrogen supplied from at least one of the first hydrogen storage alloy or the second hydrogen storage alloy, and   causing heat of the second hydrogen storage alloy in the first operating mode to be stored in the hot water storage tank at least in wintertime, and causing heat when hydrogen generated in the water electrolysis apparatus in a period different from at least the wintertime is stored in at least one of the first hydrogen storage alloy or the second hydrogen storage alloy, and heat accompanying power generation of the fuel cell apparatus using hydrogen supplied from at least one of the first hydrogen storage alloy or the second hydrogen storage alloy to be stored in the hot water storage tank.