Laundry treating apparatus indicating energy efficiency and method for indicating energy efficiency thereof

Abstract

A laundry treating apparatus may include a drum that receives laundry item therein, a heat pump that circulates a heating medium, a compressor that compresses the heating medium, a condenser that heats air to be transmitted to the drum, an expander that expands the heating medium, and an evaporator that cools air transmitted from the drum. A heater may re-heat air heated by the heat pump, and a sensing device may sense a state, such as temperature, of the heating medium. A controller may calculate energy efficiency based on the sensed state of the heating medium. Energy related information including the calculated energy efficiency may be displayed on a display so that energy efficiency may be monitored real time.

What is claimed is: 
     
         1 . A laundry treating apparatus, comprising:
 a drum configured to receive laundry items therein;   a heat pump configured to circulate a heating medium, the heat pump including a compressor configured to compress the heating medium, a condenser configured to heat air to be transmitted to the drum, an expander configured to expand the heating medium, and an evaporator configured to cool air transmitted from the drum;   a heater configured to re-heat air heated by the heat pump;   a sensing device configured to sense at least one state value of the heating medium;   a controller configured to calculate energy efficiency based on the at least one state value of the heating medium; and   a display configured to display energy related information and the calculated energy efficiency.   
     
     
         2 . The apparatus of  claim 1 , wherein the controller is configured to calculate the energy efficiency by calculating an amount of energy absorbed by the heating medium in the evaporator and an amount of energy supplied by the heating medium in the condenser. 
     
     
         3 . The apparatus of  claim 2 , wherein the at least one state value of the heating medium includes a temperature of the heating medium at least one point in a circulation path of the heating medium through the heat pump. 
     
     
         4 . The apparatus of  claim 3 , wherein the sensing device comprises a plurality of temperature sensors respectively installed in a heating medium inlet of the evaporator, a heating medium outlet of the evaporator, a heating medium inlet of the condenser, and a heating medium outlet of the condenser. 
     
     
         5 . The apparatus of  claim 2 , wherein the energy related information comprises an amount of energy absorbed by the heating medium in the evaporator and an amount of energy supplied by the heating medium in the condenser. 
     
     
         6 . The apparatus of  claim 5 , wherein the display is configured to display an amount of energy absorbed by the heating medium in the evaporator and an amount of energy supplied by the heating medium in the condenser in response to an external input received at a touch screen or a button operably coupled to the display. 
     
     
         7 . The apparatus of  claim 1 , wherein the controller is configured to calculate a power rate saved by the heat pump based on the at least one state value of the heating medium, and wherein the energy related information includes the calculated saved power rate. 
     
     
         8 . The apparatus of  claim 7 , further comprising:
 a communication device configured to communicate with an external device, and to receive power information including power rate time slot information, wherein   the controller calculates the saved power rate based on the power information received from the external device.   
     
     
         9 . The apparatus of  claim 8 , wherein the controller calculates the saved power rate based on an amount of energy absorbed by the heating medium in the evaporator. 
     
     
         10 . The apparatus of  claim 8 , wherein the sensing device comprises a plurality of temperature sensors respectively installed in a heating medium inlet and a heating medium outlet of the evaporator. 
     
     
         11 . The apparatus of  claim 8 , wherein the controller accumulates power rates saved within a predetermined period of time and re-calculates the accumulated saved power rate each time the predetermined period of time elapses. 
     
     
         12 . A method of operating a laundry treating apparatus, the method comprising:
 performing a sensing operation, comprising sensing at least one state value of a heating medium circulating in a heat pump;   performing an energy efficiency calculating operation, comprising calculating energy efficiency of the heat pump; and   performing an output operation, comprising displaying energy related information including the calculated energy efficiency of the heat pump,   wherein the energy efficiency calculating operation comprises:
 calculating an amount of thermal energy absorbed by the heating medium in an evaporator of the heat pump based on the at least one value state of the heating medium; and 
 calculating an amount of thermal energy supplied by the heating medium in a condenser of the heat pump based on the at least one state value of the heating medium. 
   
     
     
         13 . The method of  claim 12 , wherein sensing at least one state value of a heating medium comprises sensing a temperature of the heating medium introduced into the evaporator, a temperature of the heating medium discharged from the evaporator, a temperature of the heating medium introduced into the condenser, and a temperature of the heating medium discharged from the condenser. 
     
     
         14 . The method of  claim 12 , further comprising:
 performing a power rate calculating operation, comprising calculating a saved power rate based on an amount of energy absorbed by the heating medium in the evaporator, wherein the energy information includes the saved power rate.   
     
     
         15 . The method of  claim 14 , wherein sensing at least one state value of a heating medium comprises sensing a temperature of the heating medium introduced into the evaporator and a temperature of the heating medium discharged from the evaporator, and wherein
 performing a power rate calculating operation comprises:
 determining a total amount of power consumed within a predetermined period of time and calculating a saved power rate based on the total amount of power consumed and an applicable power rate for the predetermined period of time; 
 re-calculating the saved power rate at predetermined intervals corresponding to the predetermined period of time. 
   
     
     
         16 . A method of operating a laundry treating apparatus, the method comprising:
 sensing a temperature of a heating medium at least one point in a circulation path of the heating medium through a heat pump;   calculating energy efficiency of the heat pump based on the sensed temperature; and   displaying energy related information related to the operation of the laundry treating apparatus, comprising:
 receiving power rate information from an external source; 
 calculating an amount of power rate that has been saved within a predetermined period of time based on an amount of energy absorbed by the heating medium circulating through the heat pump within the predetermined period of time and the received power rate information; 
 displaying the calculated energy efficiency and saved power rate on a display; 
 re-calculating the saved power rate and the energy efficiency at predetermined intervals corresponding to the predetermined period of time; and 
 re-displaying the calculated energy efficiency and re-calculated saved power rate on the display. 
   
     
     
         17 . The method of  claim 16 , wherein calculating energy efficiency comprises:
 calculating an amount of thermal energy absorbed by the heating medium in an evaporator of the heat pump based on a first temperature of the heating medium measured at an inlet into the evaporator and a second temperature of the heating medium measured at an outlet of the evaporator; and   calculating an amount of thermal energy supplied by the heating medium in a condenser of the heat pump based on a third temperature of the heating medium measured at an inlet into the condenser and a fourth temperature of the heating medium measured at an outlet of the condenser.