Waste heat recapture from cooking appliance

Abstract

A waste heat extraction and capture device located in a stream of waste heat from a cooking appliance extracts heat energy from heated air destined for venting to an ambient exterior. A heat transfer element disposed in a vent hood above the cooking surface recovers heat for recapturing thermal energy that would otherwise be simply expelled. A fluid traveling through the heat transfer element is heated by the passing exhaust stream of waste heat, and can be stored for subsequent use, such as for potable hot water, interior space heating, or other cooking processes. An attachment strap, bracket or mechanism secures the heat transfer element in the vent hood that is typically tapered for effective heat gathering, and is positioned downstream of filters or traps for grease so as to avoid clogging the heat transfer element.

What is claimed is: 
     
         1 . A waste heat extraction device, comprising:
 a heat transfer element including a fluid vessel disposed in a stream of waste heat;   a vertical attachment securing the heat transfer element in the stream of waste heat;   a pump in fluidic communication with the fluid vessel for circulating a heated fluid through the fluid vessel;   a pump controller responsive to a temperature of the heated fluid in the fluid vessel in response to the stream of waste heat, the pump controller adapted to circulate the heated fluid based on predetermined waste heat recapture conditions; and   a recapture tank connected to the fluid vessel for receiving and storing the heated fluid.   
     
     
         2 . The device of  claim 1  wherein the waste heat recapture conditions are based on an activation of a source of waste heat and a demand for recaptured thermal energy in the heated fluid, the recapture tank engaged with a potable hot water source for sourcing a potable hot water tap. 
     
     
         3 . The device of  claim 1  wherein the waste heat recapture conditions are indicative of a temperature of the heated fluid above a threshold defined for useable recycled heat. 
     
     
         4 . The device of  claim 1  disposed in a path between a primary consumer of heat energy resulting in the waste heat and an exhaust path adapted for directing the waste heat away from a conditioned space housing the primary consumer. 
     
     
         5 . The device of  claim 4  wherein the primary consumer is a cooking appliance and the exhaust path includes a vent hood. 
     
     
         6 . The device of  claim 1  wherein the vertical attachment includes a bracket attaching the heat transfer element to an interior void of an exhaust conduit to an exterior ambient environment. 
     
     
         7 . The device of  claim 6  wherein the vertical attachment engages an interior of a circumference of the exhaust conduit, 
     
     
         8 . The device of  claim 6  wherein the vertical attachment extends transversely between opposed sides of the exhaust conduit. 
     
     
         9 . The device of  claim 1  wherein the heat transfer element is a radiator adapted for automotive applications, the radiator having a single inlet and a single outlet. 
     
     
         10 . The device of  claim 5  further comprising a plurality of heat transfer elements, the quantity of heat transfer elements based on a size of the vent hood. 
     
     
         11 . The device of  claim 10  further comprising a serial connection between the plurality of heat transfer elements, the serial connection defining a fluidic connection from the output of the respective heat transfer element to an input of a successive heat transfer element in the plurality of heat transfer elements. 
     
     
         12 . A method for recapturing waste heat from a commercial cooking facility, comprising:
 disposing a heat transfer element in a vertical orientation above a heat source emanating a stream of waste heat;   circulating a heated fluid through the heat transfer element for thermal absorption of the waste heat in the stream;   controlling a flow of the heated fluid based on predetermined waste heat recapture conditions; and   gathering the heated fluid in a recapture tank for storing and utilizing the heated fluid.   
     
     
         13 . The method of  claim 12  further comprising passing a water source through the heated fluid for receiving potable hot water. 
     
     
         14 . The method of  claim 12  further comprising directing the heated fluid to a hot water recycling application. 
     
     
         15 . The method of  claim 12  further comprising securing the heat transfer element in a vertical orientation between opposed sides of a venting conduit for exhausting waste heat from a cooking appliance. 
     
     
         16 . The method of  claim 15  wherein the venting conduit is a tapered vent hood, further comprising securing the heat transfer element between a filtering element and a propulsion source for the waste heat flow, the filtering element adapted for grease capture.