Chiller plant with ice storage

Abstract

A chiller plant is disclosed. The chiller plant includes a chiller circuit including a chiller, a first process fluid circuit, and a first heat exchanger. The chiller is configured to provide a first process fluid at a first temperature. The chiller plant also includes an air handling circuit including a plurality of ice storage tanks and an air handling unit. The chiller plant further includes a terminal cooling circuit including a plurality of terminals, the terminal cooling circuit providing a second process fluid to the plurality of terminals at a second temperature that is different from the first temperature. The terminal cooling circuit is fluidly separate from, but thermally communicates with, the chiller circuit via the first heat exchanger.

What is claimed is: 
     
         1 . A chiller plant, comprising:
 a chiller circuit including a chiller, a first process fluid circuit, and a first heat exchanger, the chiller being configured to provide a first process fluid at a first temperature;   an air handling circuit including a plurality of ice storage tanks and an air handling unit; and   a terminal cooling circuit including a plurality of terminals, the terminal cooling circuit providing a second process fluid to the plurality of terminals at a second temperature that is different from the first temperature, the terminal cooling circuit being fluidly separate from, but thermally communicating with the chiller circuit via the first heat exchanger.   
     
     
         2 . The chiller plant according to  claim 1 , wherein the first process fluid and the second process fluid are different. 
     
     
         3 . The chiller plant according to  claim 1 , wherein the ice storage tanks provide a third process fluid at a third temperature to the air handling unit. 
     
     
         4 . The chiller plant according to  claim 3 , wherein the third process fluid is the same as the first process fluid, and the third temperature is less than the first temperature. 
     
     
         5 . The chiller plant according to  claim 1 , further comprising a plurality of connecting lines, wherein the connecting lines fluidly connect the chiller circuit and the air handling circuit. 
     
     
         6 . The chiller plant according to  claim 1 , wherein the chiller circuit further comprises a second heat exchanger disposed upstream of the first heat exchanger. 
     
     
         7 . A chiller plant, comprising:
 a chiller circuit including a chiller and a process fluid circuit, the chiller being configured to provide a process fluid at a first temperature; and   an air handling circuit including a plurality of ice storage tanks and an air handling unit.   
     
     
         8 . The chiller plant according to  claim 7 , further comprising a heat exchanger disposed upstream of the plurality of terminals. 
     
     
         9 . The chiller plant according to  claim 7 , wherein the chiller circuit and the air handling circuit are operable separately, wherein the chiller provides the process fluid at the first temperature to a plurality of sensible cooling terminals, and ice in the plurality of ice storage tanks serves as a process fluid for the air handling unit. 
     
     
         10 . The chiller plant according to  claim 7 , wherein the chiller circuit and the air handling circuit are fluidly connectable such that the chiller is used to create ice for the plurality of ice storage tanks. 
     
     
         11 . A method of operating a chiller plant, the method comprising:
 receiving, by a controller, a plurality of operating factor inputs from one or more sensors in a chiller plant;   determining, by the controller, an operating mode and a setpoint based on the plurality of operating factors; and   sending, by the controller, operating states to one or more components of the chiller plant to place the chiller plant in the operating mode and at the setpoint as determined.   
     
     
         12 . The method according to  claim 11 , wherein determining, by the controller, the operating mode and the setpoint based on the plurality of operating factors includes determining the operating mode first, and using the operating mode as an input to determining the setpoint. 
     
     
         13 . The method according to  claim 11 , wherein sending, by the controller, operating states includes sending one or more of an instruction to enable or disable a flow control device, enable or disable a pump, modify a pump speed, and enable or disable a chiller.