Patent Publication Number: US-2012024334-A1

Title: Exhaust Heat Thermoelectric Generator (HETEG) System - Electric Power Generation Using the Combination of Thermoelectric Modules and Waste Exhaust Heat

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     THIS APPLICATION CLAIMS PRIORITY TO PROVISIONAL U.S. APPLICATION No. 61/274,407 FILED 17 Aug. 2009. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     REFERENCE TO SEQUENCE LISTING 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     The present invention is in the technical field of waste energy recovery. More particularly, the present invention is in the technical field of using thermoelectric modules in collaboration with wasted exhaust heat emitting from fossil fuel engines to generate electric voltage. 
     When an engine is powered by fossil fuel (natural gas, coal, wood or crude oil), only about 30% of the fuel is used to perform useful work. The rest 70% are wasted. 32 to 35% are wasted in the form of exhaust heat while 35 to 38% are wasted Carbon Dioxide pollutants. Fossil fuel engines are only about 30% efficient. 
     One type of this invention will be installed on the sides or roof of a moving vehicle. Another type of this invention will also be installed on a stationary location so that idling vehicles can plug their exhaust tails into it to generate voltage. Many other types of this invention will be shown in the cause of this disclosure. 
     This invention will recover and reuse a large portion of the 32 to 35% wasted exhaust heat. This invention will also increase the efficiency of a fossil fuel engine from 30 to at least 45%. 
     A typical thermoelectric module has three main operating quantities. The quantities are hot temperature, cold temperature and voltage. When any two of the three quantities are adequately applied to the appropriate points on the thermoelectric module, the third quantity is produced. As an example, when adequate heat is applied to hot plate side and cold temperature is applied to cold plate side, voltage is generated in output terminals. 
     It is therefore not uncommon to generate electric power at the electrical terminals of a thermoelectric module with thermoelectric modules that have a substantial amount of figure of merit zT, and when there is a temperature difference between the hot plate side and cold plate side. (This temperature difference is also known as delta temperature dT). A significant amount of voltage is generated when a large delta temperature is present. Also, a larger amount of voltage is generated when many thermoelectric modules are connected together, in series or parallel arrangements. 
     Other inventors have attempted to generate electric energy with thermoelectric modules. The limitations experienced by prior arts are two folds; firstly, there is not an adequate thermal insulation that prevents heat escape from the hot plate side. In most prior arts, when heat is applied to the hot plate side, a significant amount of the applied heat escapes from the periphery of the hot plate side. Due to the close proximity of hot and cold plate sides, the escaped heat finds its way to the cold plate side. The escaped heat causes the cold plate side temperature to increase as undesired, therefore, reducing the value of delta temperature. A small delta temperature will result in a small generated voltage. 
     My present invention will insulate and isolate the hot plate side and prevent same from influencing the cold plate side. 
     The second limitation suffered by prior arts is the crowded space where the thermoelectric modules are installed. When used in an automotive, prior art thermoelectric generators are installed under a vehicle where there is too much competition for space with other vehicle parts. A crowded and limited space reduces the usable quantity and size of the thermoelectric modules, therefore limiting the amount of generated voltage. Moreover, in a crowded location such as under the vehicle, the cold side temperature will never be colder than the ambient temperature; in fact, the cold side temperature will be warmer than ambient temperature. As a result, thermoelectric devices will not function at their optimum when their cold side temperature is warmer than ambient. 
     My present invention overcomes the known limitations of prior arts by arranging a large number of thermoelectric modules in an array and in an unrestricted space before they are used on an automobile. When my present invention is used on the periphery of a moving machinery, wind gust will cool the cold side plate. 
     My present invention will, when mounted on the periphery (roof or sides) of a vehicle, generate enough energy such that vehicle alternator will not be needed any more. Further, extra energy will be generated for storage and future use by the same vehicle or by another. Moreover, the stored energy can be used in homes, camp sites, boats, factories and anywhere energy is needed. 
     My present invention will increase the miles per gallon fuel usage of any vehicle that uses my exhaust heat thermoelectric generator (HETEG) device without introducing additional aerodynamic drag, weight increase or engine load. 
     Another advantage of my present invention is, a plurality of said invention can be installed in a fixed location such as but not limited to truck stops, railway stations, ship docks, airports or factory sites, so that when vehicles such as but not limited to trucks, trains, ships or planes are stationary and idling, their exhaust tails can be connected into inlet pipes of said plurality of said invention at said stationary location. 
     Yet, another advantage of my present invention is, when installed on vehicles such as but limited to trucks, trains, ships or planes, and when said vehicles are stationary and idling in a location such as but not limited to truck stops, loading docks, railway stations, ship ports, airports or factory sites, output voltage of said invention can be connected to a network grid of other energy sources or to a charging station. Also, a stationary pool of water can be used boost the efficiency of my present invention. 
     Further, my present invention will reduce the quantity of Carbon Dioxide emitted into the atmosphere by fossil fuel engines, therefore, reducing greenhouse effect. 
     Further, my present invention will reduce our dependency on fossil fuel; therefore, cost of fossil fuel will drop, creating a positive economic and national security impact. 
     When the environment is less polluted as a result of my present invention, there will be a reduction in respiratory illness which will prolong the lives of our citizens and reduce medical expenses. Also, when national security of any nation is not threatened, regional conflicts will cease. 
     It is anticipated that my present HETEG device invention alone will introduce additional weight if used on a moving vehicle. However, if my HETEG device is used with the entire HETEG system, a significant weight reduction will be achieved. The HETEG system are: 
     1—a multi-element HETEG device, 
     2—an Exhaust Bypass System (EBS), 
     3—a meshed wire exhaust pipe sandwiched with thermal insulation, and 
     4—a Systems Control Unit. 
     Benefits and advantages of my present invention is not limited to the areas than I have listed. 
     SUMMARY OF THE INVENTION 
     The present invention provides an improved system for generating electric energy by using the combination of wasted exhaust heat from fossil fuel engines and thermoelectric modules. 
     The method includes using a plurality of thermoelectric modules, together with exhaust heat from fossil fuel engines to generate electrical energy. The method also includes connecting several thermoelectric modules in an array of electrical series and parallel arrangements to achieve large output voltage and load current. 
     Further, the method includes conserving the exhaust heat from exhaust manifold, through the exhaust cylinder, up to the exhaust tail, by using a meshed sandwiched light weight exhaust pipe to convey exhaust heat into hot plate side of the plurality of thermoelectric modules. 
     The method further includes an exhaust bypass system (EBS) that serves three purposes, namely:
         1. it protects the thermoelectric modules from heat damage by diverting the exhaust heat away from the HETEG device when a temperature sensor senses an excessive exhaust heat;   2. it turns the HETEG device ON by allowing exhaust heat to enter the HETEG device, and turns it OFF by preventing exhaust heat from entering the HETEG device; and,   3. it keeps output voltage relatively constant by regulating the quantity of exhaust heat entering HETEG device.       

     Further, the method includes channeling temperature of lower value, lower than the temperature used on the hot plate side, onto the cold plate side, therefore creating a large temperature difference between hot plate side and cold plate side of thermoelectric modules. 
     The method also includes connecting the electrical output voltages of a multi output 
     HETEG device to a voltage selection unit for processing into a desired value by connecting them in series and or parallel arrangements. 
     The method further includes connecting the electrical output of the voltage selector unit to a voltage stabilizer/charger unit such as Direct Current to Direct Current (DC-DC) converter. 
     The method further includes connecting the output of the DC-DC converter to an electrical load such as replace vehicle alternators or use to charge discharged batteries. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       The drawings illustrate several preferred embodiments of the invention with same numerical referring to similar parts throughout the several views, wherein: 
         FIG. 1  is a HETEG system showing electrical and mechanical connections. 
         FIG. 2  is a HETEG device mounted on the side of a truck. 
         FIG. 3A  is a side view of a HETEG system mounted on the roof of a mini-van. 
         FIG. 3B  is a front view of a HETEG system mounted on the roof of a mini-van. 
         FIG. 3C  is a top view of a HETEG system mounted on the roof of a mini-van. 
         FIG. 3D  is a back view of a HETEG system mounted on the roof of a mini-van. 
         FIG. 4  is a pictorial view of several stationary HETEG systems ready for exhaust pipes of idling semi-trucks to be plugged into them. 
         FIG. 5  is a three element thermoelectric module with inputs and outputs. 
         FIG. 6A  is a top view of a thermoelectric module. 
         FIG. 6B  is a front view of a thermoelectric module. 
         FIG. 6C  is a back view of a thermoelectric module. 
         FIG. 7  is a diagram if thermoelectric modules connected in series and parallel arrangements. 
         FIG. 8A  is a front view of a five partition HETEG device 
         FIG. 8B  is a left side view of a five partition HETEG device 
         FIG. 8C  is a right side view of a five partition HETEG device 
         FIG. 8D  is a B-B view of a five partition HETEG device 
         FIG. 9  is orthogonal view of hot plate. 
         FIG. 10A  is a top view of a two sided HETEG device without a by-pass system. 
         FIG. 10B  is the bottom views of a two sided HETEG device with a by-pass system. 
         FIG. 10C  is the back view of  FIG. 10A . 
         FIG. 10D  is the front view of  FIG. 10A . 
         FIG. 10E  is G-G view of  FIG. 10D . 
         FIG. 10E  is expanded view of a section in  FIG. 10A . 
         FIG. 11A  is a left side view of a roof type HETEG device. 
         FIG. 11B  is a right side view of a roof type HETEG device. 
         FIG. 11C  is a inside side view of a roof type HETEG device. 
         FIG. 12  is orthogonal view of components of mounting bracket. 
         FIG. 13  is orthogonal view of a three-channel EBS. 
         FIG. 14  is a functional diagram of a three-channel EBS. 
         FIG. 15  is a vane table of a three-channel EBS. 
         FIG. 16A  is a sectional view of internal components of a four-channel four-channel EBS when it is OFF. 
         FIG. 16B  is a sectional view of internal components of a four-channel four-channel EBS when it is ON. 
         FIG. 16C  is a sectional view of internal components of a four-channel four-channel EBS when it is on AUTO. 
         FIG. 16D  is a vane table of a four-channel EBS. 
         FIG. 17  a time plot of control algorithm result. 
         FIG. 18  is the control schematics of a HETEG system showing all components. 
         FIG. 19A  is a voltage selector unit with two voltage outputs connected in series. 
         FIG. 19B  is a voltage selector unit with two voltage outputs connected in parallel. 
         FIG. 19C  is a voltage selector unit with four voltage outputs connected in parallel. 
         FIG. 19D  is a voltage selector unit with four voltage outputs connected in parallel and series. 
         FIG. 19E  is a voltage selector unit with two voltage outputs connected in parallel. 
         FIG. 20A  is a side view of meshed wire tube sandwiched with fire resistant thermal insulation. 
         FIG. 20B  is a top view of meshed wire tube sandwiched with fire resistant thermal insulation. 
         FIG. 20C  is an orthogonal view of meshed wire tube sandwiched with fire resistant thermal insulation. 
     
    
    
     DETAILED DESCRIPTION OF THE DISCLOSURE 
     A complete exhaust heat thermoelectric generator (HETEG) system, shown in  FIG. 1  is comprised of four essential components; each component has several embodiments. The components include a multi-element HETEG device  1 , an Exhaust Bypass System (EBS)  2 , a meshed wire exhaust pipe sandwiched with thermal insulation  3 , and a Systems Control Unit  4 . 
     A multi-array HETEG device  1  is shown in  FIG. 2  is mounted on the side of a truck. 
     A HETEG device  1  mounted on the roof of a mini-van is shown in  FIG. 3 .  FIG. 4  shows many HETEG devices mounted on a stationary location in readiness for idling trucks to plug their exhaust tails into them. 
     The inside construction of a HETEG element is shown in  FIG. 5 .  FIG. 5  is a three element N-type and P-type module having a hot plate side  5  and a cold plate side  6 . Hot plate side  5  is attached to exhaust channel  7 . The outside wall of exhaust channel  7  is for mounting HETEG on a structure such as the roof of sides of a vehicle  9 . The inside walls of exhaust channel  7  is constructed with a thermal insulated plate  10  shaped in saw-tooth pattern. The thermal insulated plate  10  is preferred to be of mica material to ensure durability and light weight. A heat dissipating plate  11  is securely attached to cold plate side  6 . When exhaust heat  50  is applied to hot plate side  5 , and simultaneously cold temperature is applied to heat dissipating plate  11 , a thermal flow  12  takes place. Electrons  13  on the hot side  5  are more energized than on the cold side  6 . Electrons  13  will flow from the hot side  5  to the cold side  6 . In the N-type semiconductor  15 , electron  105  flow will take place while in the P-type  16 , electron holes  14  will flow. If an electrical load  80  is applied to the electrical terminals  66 , an electric current  17  will flow through contact  18 . Electric wires  66  and contact plates  18  are secured using a low resistance bonding method such as brazing at point  81 . 
     One construction detail of the hot plate side  5  is shown in  FIG. 9 . A slot  99  is cut along the length of hot plate  5 . 
     Several views of a typical one module thermoelectric device are shown in  FIG. 6A  through  FIG. 6C . The module has multiple elements. The module of  FIG. 6  includes a hot plate side  5 , a cold plate side  6  and a pair of electrical terminals  66 . 
     When a thermoelectric module is used as a generator such as in this invention, hot temperature is applied to the hot plate side  5  and cold temperature is applied to the cold plate side  6 . Temperature difference between the hot plate side  5  and cold plate side  6  is known as delta temperature, dT. For example, if temperature T h  is applied to hot plate side  5  and temperature Tc is simultaneously applied to cold plate side  6 , then, 
       dT= T   h   −T   c   [°K.]   (1)
         T c  is less than T h  so that dT remains a positive number.       

     Using the three element thermoelectric module in  FIG. 5  as an example, the output voltage, V o  is determined by, 
         V   o   =S   m *dT   (2)
         Where,   S m  is Module&#39;s average Seebeck coefficient [volt/°K.]. S m  is also a function of figure of merit zT of the material.       

       FIG. 7  has a combination of series and parallel arrangements, therefore, considering load resistance R L  and output current I, output voltage is, 
         V   o   =I *( R   m   +R   L )   (3)
         Where,   R m  is Module&#39;s average resistance [ohms] and a function of the thermoelectric module.       

     Output current, I is, 
     
       
         
           
             
               
                 
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     Output power [watts] is therefore, 
     
       
         
           
             
               
                 
                   
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             Where, 
             S 1  is first series element. 
             S 2  is second series element. 
             S n  is n th  series element. 
             P 1  is first parallel path. 
             P 2  is second parallel path. 
             P n  is n th  parallel path. 
             N s  is the total number of series arrangements. 
             N T  is total number of elements in the array. 
             N p  is total number of parallel paths. 
           
         
       
    
     OTHER HETEG EMBODIMENTS 
     One embodiment: HETEG device that can be installed on the periphery of a train. 
     One embodiment: HETEG device that can be installed on the periphery of a plane. 
     One embodiment: HETEG device that can be installed in the ballast of a ship. 
     One embodiment: HETEG device that can be installed on a chimney. 
     Other embodiment may not have been listed here. 
     A two dimensional view of the inside components of the HETEG device  1  of  FIG. 2  is further shown in  FIG. 8A through 8D . The  FIG. 8  device has six sides in the shape of a box. The sides include a first side  20 , a second side  21 , a third side  22  and a forth side  23 . The second side  21  is on opposite of first side  20 . Second side  21  is the anchor side for installation to the side of a vehicle  9 . HETEG shown in  FIG. 8  also includes a third side  22  and a forth side  23 . Third side  22  and forth side  23  are top and bottom respectively of HETEG. 
       FIG. 8  HETEG device further includes a fifth side  24  and a sixth side  25  which are left and right sides respectively of the HETEG device. At the bottom location of fifth side  24  is an exhaust heat inlet pipe  26  securely attached to inlet hole  27 . At the top location of sixth side  25 , exhaust heat outlet pipe  28  is securely attached to outlet hole  29 . A flow of exhaust heat  50  leaves fossil fuel exhaust pipe  28  and enters HETEG device through exhaust heat inlet pipe  26  and leaves through outlet pipe  28 . Exhaust heat inlet pipe  26  and outlet pipe  28  are preferably made of heat resisting or other thermal insulating materials. 
     Outside shape of fifth side  24  is aerodynamically curved to prevent wind drag when vehicle is in motion. 
     Third side  22 , forth side  23 , fifth side  24  and sixth side  25  of the HETEG device as shown in  FIG. 8  are the outside surfaces. 
     First side  20  has two layers, a first layer  94  and a second layer  97 . First layer  94  is the same as hot plate side  5 . Second layer  97  is the same as the heat dissipating plate  11 . Thermoelectric elements  106  are sandwiched between hot plate side  5  and heat dissipating plate  11 . 
     As shown in  FIG. 8D , first side  20 , second side  21 , third side  22 , forth side  23 , fifth side  24  and sixth side  25  are securely attached together at their corners with screws  30 . None flammable heat resisting compound  19  as depicted in  FIG. 1  OF is spread between the corner joints to ensure a tight fit. The non-flammable heat resisting compound  19  is applied and allowed to dry to form a solid heat escape barrier. 
     The inside compartment of HETEG device is shown in  FIG. 8D  is partitioned into multi-layer heat chambers. The chambers are a first chamber M, a second chamber N, a third chamber O, a forth chamber P and a fifth chamber Q. Each chamber partition creates a heat path that maximizes the effect of heat on its portion of hot plate  5 . The cross sectional area of each chamber partition is equivalent to or more than the cross sectional area of the exhaust pipe that conveys the exhaust heat  50 . The chamber cross sectional area is chosen to prevent exhaust back stroke on fossil fuel engine. Each heat chamber partition M, N, O, P and Q is separated by partition separator plate  31 . 
     Partition separator plate  31  is preferably made of a rigid flat heat resisting material or other thermal insulating materials. Each partition separator  31  slides into slot  99  of hot plate  5 . 
       FIG. 1  is a general overview of the HETEG system showing all electrical and mechanical connections. The exhaust pipes that conveys exhaust heat  50  from fossil fuel engine into HETEG device includes a first exhaust pipe  32  a second exhaust pipe  3  and a third exhaust pipe  36 . 
     Exhaust heat  50  leaves the exhaust manifold  33  through first exhaust pipe  32 . First exhaust pipe  32  connects to inlet pipe  34  of exhaust cylinder  35 . Second exhaust pipe  3  connects to outlet pipe  37  of exhaust cylinder  35  and to exhaust bypass system (EBS)  2 . Third exhaust pipe  36  connects EBS  2  to exhaust heat inlet pipe  26 . 
     First exhaust pipe  32 , second exhaust pipe  3  and third exhaust pipe  36  are all made with meshed wire sandwiched with thermal insulation material  98  as in  FIG. 20  to prevent any heat loss along its path. Meshed wire sandwiched with thermal insulation material  98  is designed to be light in weight. Exhaust cylinder  35  is insulated with heat resisting material  38  in order to prevent any heat loss. A preferred heat resisting material is mica sheets. 
       FIG. 20A through 20C  show a preferred embodiment of a thermally insulated light weight exhaust pipe  3  construction. A cross sectional view of the thermally insulated robust light weight pipe  3  is shown in  FIGS. 20B and 20C . Exhaust pipe  3  includes an inner tube  39 , meshed wire  40  sandwiched with thermal insulations  41 . The meshed wire  40  also serves as reinforcement for durability and robustness Inner tube  39  is polished with ceramic coating to prevent accumulation of smoke soot. 
     Referring now to the invention in more details according to  FIG. 8D , there is shown exhaust heat  50  entering the HETEG device through exhaust heat inlet pipe  26  and travels into chamber partition M at point M 1 . Exhaust heat  50  continues its journey in chamber partition M to the end of chamber partition M at point M 2 . At point M 2 , exhaust heat  50  curves to chamber partition N at point N 1 . Exhaust heat  50  continues from chamber partition N to O and to chamber partition P and further to chamber partition Q. At point Q 2 , exhaust heat  50  leaves HETEG device through outlet pipe  28  and into the atmosphere. 
     As exhaust heat  50  enters each chamber partition M, N, O, P and Q, it is incident on a saw-tooth wall fins  10 . The saw-tooth shape of the wall fins  10  causes the entrant exhaust heat  50  to undulate. As exhaust heat  50  undulates, it bounces on hot plate  5 , causing hot plate  5  to absorb all the exhaust heat  50  energy. Saw-tooth wall fin  10  is made of light weight heat resisting material such as mica. 
     Exhaust heat undulation  42  inside chamber partitions M, N, O, P and Q serve two purposes. Firstly, exhaust heat  50  bounces on hot plate  5  as undulation takes place. Impact of the bounce increases the heat on hot plate  5 . Secondly, exhaust heat undulation  42  cause exhaust heat  50  to spend additional time inside each chamber partition M, N, O, P and Q. The more time exhaust heat  50  spends inside chamber partitions M, N, O, P and Q, the more hot plate  5  absorbs the heat energy. 
     To ensure a secure attachment of thermoelectric modules onto hot plate  5 , a securing bracket assembly  101  is used. The securing bracket assembly  101  shown in  FIG. 12  includes a pair of bracket elbows  43  and a pair of first fastening screws  44 , second pair of fastening screws  45 , a pair of adjustment nut  46 , a pair of space washer  47  and a rectangular bar  48 . The quantity of securing bracket assembly  101  is dependent on the number and size of thermoelectric modules in a HETEG assembly. 
     One of bracket elbow  43  is used at each end of rectangular bar  48 . Rectangular bar  48  has one hole in the center at each end where second fastening screw  45  passes through. First fastening screw  44  serve two purposes; they secure bracket elbow assembly  43  unto the thermally insulated outside frames of the HETEG device. First fastening screw  44  also ensure that necessary adjustment is made to maintain permanent and secure physical contact between hot plate  5  and heat dissipating plate  11 . 
     Bracket elbow assembly  101  is preferably made with high temperature heat resistant plate preferably mica bars. 
     HETEG embodiment shown in  FIG. 2  receives its cold side temperature Tc, when vehicle  9  is in motion. As vehicle  9  moves, heat dissipating plate  11  cuts through passing wind  49 . In the process, cold side plate  6  is cooled by wind gust. During winter seasons, the cold side plate  6  is colder by wind chill factor. 
     A HETEG device installed in a stationary location such as seen in  FIG. 4  can is cooled by ambient temperature or by a pool of water circulating on heat dissipating plate  11 . 
     One essential embodiment of the HETEG system is the Exhaust By-pass System (EBS)  2 . The inside lining  107  of EBS  2  is a heat resistant material such as mica. The outside material of EBS may be any rigid material such as metal sheet. EBS  2  can be of three or four channels. The number of EBS  2  channels depends on the HETEG configuration it is serving. Construction details of a three-channel EBS  2  are shown in  FIG. 13 . The inner components and functions of a three-channel EBS  2  are shown in  FIG. 14 . A four-channel EBS  2  is shown in  FIG. 16 . 
     For example, when exhaust heat inlet pipe  26  and exhaust outlet pipes  28  are in close proximity as with the HETEG device shown in  FIG. 10  and  FIG. 11 , a four-channel EBS  2  is used. Alternatively, when the physical location of exhaust heat inlet pipe  26  and exhaust outlet pipes  28  are far apart from one another as in  FIG. 1 , a three-channel EBS  2  is desired. 
     When a HETEG device is installed, it may be necessary to turn it OFF by diverting exhaust heat  50  away from chamber partitions M, N, O, P and Q. This can be achieved by installing an EBS  2  on the exhaust line. EBS  2  is also used to protect the thermoelectric elements from damage when excessive heat, detected by a temperature sensor  57 , is present in chamber partition M. 
     There are several locations where EBS  2  can be installed. In  FIG. 1 , the three-channel EBS  2  is installed between exhaust cylinder  35  and HETEG device. EBS is ON is when exhaust heat  50  enters the HETEG device and the device functions as a generator. OFF is when exhaust heat  50  does not enter the HETEG device and no voltage is generated. EBS  2  and its controller can regulate the quantity of exhaust heat  50  that enters HETEG to maintain a constant voltage. EBS  2  is in the AUTO mode when it is automatically controlling the output voltage of a HETEG device. 
     The three-channel EBS  2  shown in  FIG. 14  has a first channel  51 , a second channel  52 , a third channel  54  and a vane  55 . First channel  51  connects to exhaust cylinder  35 . Second channel  52  connects to the inlet pipe  26  and third channel  53  is a bypass exhaust pipe  54  for releasing exhaust heat  50  into the atmosphere. The internal construction of EBS  2  includes vane  55  and a vane support  111 . Vane  55  is securedly attached to a rod  96 . Rod  96  is attached to pivot at the intersection  56  between second channel  52  and third channel  54 . Vane  55  operates by flapping between first position  108  and second position  109 . When vane  55  is in first position  108 , exhaust heat  50  will only travel into second channel  52  and into HETEG device. This is the ON or DEFAULT position because the HETEG in operating continuously. When vane  55  is in second position  109 , exhaust heat will only travel into third channel  54  preventing HETEG from operating. This is the OFF position because HETEG is not generating any voltage. When vane  55  is between first position  108  and second position  109 , such as in position  110 , a proportion of exhaust heat  50  enters second channel  52  and another proportion enters third channel  53 . This is the AUTO mode because HETEG output is regulated automatically by controller  59  based on delta temperature dT. Output temperature V o  is relatively constant in the AUTO mode. 
     When the three-channel EBS  2  is in the ON position, vane  55  rests on vane support  111 . The contact between vane  55  and vane support  111  ensures that no exhaust heat  50  escapes into second channel  52 . 
     A vane table is shown in  FIG. 15 .  FIG. 15  table corresponds to the operation of the three-channel EBS  2 . 
     The three-channel EBS  2  shown in  FIG. 13  also includes a toggle switch  102 . Toggle switch  102  is used to by-pass the operations of the algorithm. At one position  103 , toggle switch  102  will allow control algorithm  84  to be functional. In another position  104 , toggle switch  102  will turn off control algorithm  84 . 
     The inside details of a four-channel EBS  64  is shown in  FIGS. 16A and 16B . Functional use of a four-channel EBS  2  is depicted in  FIG. 3  and  FIG. 11 . A four-channel EBS  2  shown in  FIG. 16  has four-channels and three vanes. A first channel  60  connects to exhaust tail  37  of a vehicle  65 . A second channel  61  connects to exhaust inlet pipe  26  of a HETEG device. A third channel  62  connects to exhaust outlet  28  of a HETEG device. A forth channel  63  allows exhaust heat  50  to escape to the atmosphere. First channel  60  and second channel  61  is constructed with one first continuous pipe  69 . Third channel  62  and forth channel  63  is made of another second continuous pipe  70 . An exhaust bypass pipe  68  perpendicularly connects the middle points of the first continuous pipe  69  and second continuous pipe  70 . First channel  60 , second channel  61 , third channel  62  and forth channel  63  are pipes made with meshed wire exhaust pipe sandwiched with thermal insulation  98 . 
     Further describing the functionality of the four-channel EBS  64  of  FIG. 16 , a first vane  71  is attached to and operates in the middle of exhaust by-pass  68 . A second vane  72  operates inside the second channel  61  and a third vane  73  operates inside the third channel  62 . The diameter of each vane is slightly less than the diameter of the channel it is serving; therefore, an unrestricted but tight movement of vanes is taking place. 
     The four-channel EBS  64  also includes a spur gear housing and assembly  74 . The spur gear housing assembly  74  contains three spur gears, namely, a first spur gear  75 , a second spur gear  76 , and a third spur gear  77 . Spur gear housing assembly  74  has upper housing cover and lower housing cover. Spur gear housing assembly  74  also contains lubricating agent  78  to cause first spur gear  75 , second spur gear  76  and third spur gear  77  to rotate freely and avoid wear during operation. First spur gear  75  is installed horizontally inside spur gear box housing  74 . Second spur gear  76  and third spur gear  77  are installed vertically and opposite of each other. Second spur gear  76  and third spur gear  77  are also installed perpendicularly to first spur gear  75 . The teeth of all three spur gears  75 ,  76  and  77  are engaged with each other as shown in  FIG. 16 . First vane  71  is attached to first spur gear  75 . Second vane  72  is attached to second spur gear  76 . Third vane  73  is attached to third spur gear  77 . 
     Using  FIG. 16B  to describe the ON position of the four-channel EBS  64 , first vane  71  is perpendicular with the walls of bypass pipe  68 , thus restricting the flow of exhaust heat  50  from first channel  60  to forth channel  63 . Second vane  72  is parallel with second channel  61 , thereby allowing exhaust heat  50  to travel from first channel  60  to second channel  61 . Also, third vane  73  is parallel with third channel  62 , thereby allowing exhaust heat  50  to flow from HETEG exhaust outlet  100  to forth channel  63 . 
     Using  FIG. 16A  to describe the OFF position of the four-channel EBS  64 , first vane  71  is parallel with the walls of bypass pipe  68 , thus allowing the flow of exhaust heat  50  from first channel  60  to forth channel  63 . Second vane  72  is perpendicular with second channel  61 , thereby preventing exhaust heat  50  from travelling from first channel  60  to second channel  61 . Also, third vane  73  is perpendicular with third channel  62 , thereby preventing exhaust heat  50  from traveling from HETEG exhaust outlet  100  to forth channel  63 . 
     Using  FIG. 16C  to describe the AUTO position of the four-channel EBS  64 , first vane  71  is partially blocking bypass pipe  68 , thus allowing the flow of some quantity of exhaust heat  50  from first channel  60  to forth channel  63 . Second vane  72  is partially blocking second channel  61 , thereby preventing some exhaust heat  50  from travelling from first channel  60  to second channel  61 . Also, third vane  73  is partially blocking third channel  62 , thereby preventing some exhaust heat  50  from traveling from HETEG exhaust outlet  100  to forth channel  63 . 
     In  FIG. 16D , a four-channel vane table that describes the inputs and impacts of a four-channel EBS  64  is shown. First column of vane table are vane positions of first vane  71 , second vane  72  and third vane  73 . Second column of vane table is HETEG output in response to positions of first vane  71 , second vane  72  and third vane  73 . The responses are ON, OFF and AUTO results. 
     Continuing on  FIG. 16 , first spur gear  75  is attached to a control mechanism, preferably a position solenoid  83 . A control algorithm  84  embedded into System Control Unit (SCU)  4  and temperature sensor  87 , determines the operation of position solenoid  83 . Position solenoid  83  controls rod  96 . Rod  96  controls first vane  71 , second vane  72  and third vane  73 . First vane  71 , second vane  72  and third vane  73  controls the flow of exhaust heat  50  inside first channel  60 , second channel  61  and third channel  62  respectively. 
     As exhaust heat  50  enters hot plate  5 , temperature sensor  57  reads the quantity of heat on hot plate  5 . Temperature sensor value T h sensed    86  is relayed to control algorithm  84 . Control algorithm  84  processes sensed temperature T h     —     sensed    86  and decides how and when to operate position solenoid  83 . 
     An example of a temperature sensor  57  reading during a typical operation is shown in  FIG. 17 . Top graph is a time plot of sensed temperature values in relation with operating points. The essential operating point is the maximum safe operating temperature of HETEG. The bottom graph is a time plot of HETEG output due to the operation of position solenoid  83 . 
     Continuing with  FIG. 17 , let T max +T 1  represent the maximum safe operating temperature of our HETEG device. Maximum operating temperature is separated into two quantities, T max  and T 1  in order to produce an efficient control algorithm  84 . T 1  is introduced to prevent sporadic ON and OFF toggling when temperature sensor  57  is doddering above  575  and below T max . Temperature sensor  57  is installed near chamber partition M. 
     When fossil fuel engine is running and exhaust heat  50  is passing through HETEG device, temperature sensor  57  begins to measure the temperature of exhaust heat  50 . HETEG is in the ON state at this initial stage. When sensed temperature T h     —     sensed    86  reaches or exceeds T max +T 1  as shown in point  87  in  FIG. 17 , HETEG is switched to OFF by the operation of position solenoid  83 . Exhaust heat  50  now passes through by-pass exhaust  68  at which time T h     —     sensed    86  begins to cool down as shown by point  88 . When T h sensed  drops to below T max  as indicated by point  89 , position solenoid  83  is de-energized and HETEG is turned ON. 
     A stepper motor  90  can be used in place of a position solenoid  83  to provide operations of rod  96 . The operation thus causes HETEG to go ON or OFF. A stepper motor  90  also provides a continuous control of rod  96  for AUTO operations. 
     One preferred embodiment of the HETEG system is the Systems Control Unit (SCU)  4  is displayed in  FIG. 18 . A SCU  4  includes a voltage selector unit  91 , a DC-DC converter unit  92 , a control algorithm  84  and a voltage charger/regulator unit  93 . Voltage selector unit  91  is used to arrange HETEG output voltage V 1 , V 2 , V 3  and V 4  into series and parallel combinations as shown in  FIG. 19 .  FIG. 19A  shows V 1  and V 2  connected in series.  FIG. 19B  is V 1  and V 2  connected in parallel.  FIG. 19C ,  19 D and  19 E depict V 1 , V 2 , V 3  and V 4    66  connected in series and parallel arrangements. Series and parallel arrangements ensure that the desired voltage is achieved. Output voltages V 1 , V 2 , V 3  and V 4    66  from HETEG device serve as inputs to voltage selector unit  91 . 
     One preferred embodiment of the HETEG system is a DC-DC converter  92  shown in  FIG. 18 . Converter  92  receives input voltage V 1 , V 2 , V 3  and V 4    67  provided by voltage selector unit  91 . Voltages  67  are conditioned and sent out as V 1 , V 2 , V 3  and V 4    95 . An electrical load  80  such as a rechargeable battery is connected across V 1 , V 2 , V 3  and V 4    95 . 
     While the invention has been taught with specific reference to the above embodiments, a person having ordinary skill in the art will recognize that changes can be made in form and detail without departing from the spirit and the scope of the invention. The described embodiments are to be considered in all respects only as illustrative and not restrictive. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope. Combinations of any of the methods, systems, and device described hereinabove are also contemplated and within the scope of the invention.