Method and apparatus for power generation using waste heat

Abstract

According to the present invention, a method and apparatus for generating power aboard a marine vessel is provided. The method comprises the steps of: (a) providing a Rankine Cycle device that includes at least one of each of an evaporator, a turbo-generator that includes a turbine coupled with an electrical generator, a condenser, and a refrigerant feed pump; (b) disposing the one or more evaporators within an exhaust duct of a power plant of the marine vessel; (c) operating the power plant; and (d) selectively pumping refrigerant through the Rankine Cycle device, wherein refrigerant exiting the evaporator powers the turbine, which in turn powers the generator to produce power.

1 . An apparatus for generating power using exhaust from a marine power plant, the apparatus comprising: 
 an evaporator operable to be disposed within the exhaust from the marine power plant;    a turbo-generator that includes a turbine coupled with an electrical generator;    a condenser having a plurality of tubes disposed within a housing, wherein the tubes form a closed circuit within the housing that is sized to permit a flow of coolant into and out of the condenser; and    a refrigerant feed pump operable to pump refrigerant.    
     
     
         2 . The apparatus of  claim 1 , further comprising a coolant source that provides the coolant flow into and out of the condenser.  
     
     
         3 . The apparatus of  claim 2 , wherein the coolant source is environmental water.  
     
     
         4 . The apparatus of  claim 2 , further comprising a selectively operable bypass valve disposed within the apparatus and positioned to provide a path between the evaporator and the condenser, so that refrigerant may be selectively bypassed around the turbo-generator.  
     
     
         5 . The apparatus of  claim 1 , further comprising a recuperator disposed within the condenser, and the recuperator is positioned within the apparatus such that refrigerant from the refrigerant feed pump enters the recuperator and refrigerant exiting the recuperator passes into the evaporator.  
     
     
         6 . The apparatus of  claim 1 , further comprising a pair of the refrigerant feed pumps operable to pump refrigerant, wherein one of the feed pumps is connected to the condenser adjacent a first lengthwise end of the condenser, and the other of the feed pumps is connected to the condenser adjacent a second lengthwise end of the condenser, opposite the first lengthwise end.  
     
     
         7 . The apparatus of  claim 1 , wherein the condenser has a selectively removable access panel attached to a first lengthwise end of the housing, wherein removal of the access panel permits access to the plurality of tubes.  
     
     
         8 . A method for generating power aboard a marine vessel, comprising the steps of: 
 providing a Rankine Cycle device that includes at least one of each of an evaporator, a turbo-generator that includes a turbine coupled with an electrical generator, a condenser, and a refrigerant feed pump;    disposing the one or more evaporators within an exhaust duct of a power plant of the marine vessel;    operating the power plant; and    selectively pumping refrigerant through the Rankine Cycle device.    
     
     
         9 . The method of  claim 8 , further comprising the steps of: 
 disposing a selectively operable bypass valve disposed within the device, positioned to provide a path between the evaporator and the condenser; and    selectively operating the bypass valve to bypass at least a portion of the refrigerant flow around the turbo-generator.    
     
     
         10 . The method of  claim 9 , wherein the bypass valve is selectively operated to bypass refrigerant around the turbo-generator during start-up of the Rankine Cycle device and during shut-down of the Rankine Cycle device.  
     
     
         11 . The method of  claim 9 , wherein the bypass valve is selectively operated to bypass refrigerant around the turbo-generator when the turbo-generator is inoperable.  
     
     
         12 . A method for generating power, comprising the steps of: 
 providing a Rankine Cycle device that includes at least one of each of an evaporator, a turbo-generator that includes a turbine coupled with an electrical generator, a condenser, and a refrigerant feed pump;    disposing the one or more evaporators within an exhaust duct of a power plant of a marine vessel;    operating the power plant; and    selectively pumping refrigerant through the Rankine Cycle device.