Patent Publication Number: US-2020277881-A1

Title: System and process for transforming thermal energy into kinetic energy

Description:
FIELD OF THE INVENTION 
     The invention is from the field of energy conversion. Specifically the invention is from the field of transforming thermal energy into kinetic energy. 
     BACKGROUND OF THE INVENTION 
     Processes that transform external thermal energy contained in a process fluid into kinetic energy by using an external source of thermal energy to heat the process fluid are well-known and used. 
     These well-known processes use one single process fluid in one single cycle to extract physical work from external thermal energy. In most cases the process fluid used is water. The process fluid is heated by the external thermal energy above the evaporation temperature of the process fluid in order to have the process fluid change from the liquid phase to the gaseous phase. Pressurising the process fluid at low temperature before heating it requires a certain specific amount of kinetic energy. Heating the pressurised process fluid above its evaporation temperature causes a phase change from the liquid state to the gas state of the used process fluid. The phase change from liquid to gaseous state causes a significant increase of volume. In case of water the increase of volume is about 1,673 times. This increase in volume allows easily extracting kinetic energy from the expansion of the gaseous phase of the process fluid, which exceeds by far the amount of kinetic energy used at the beginning to pressurise the process fluid. After the expansion this process fluid is then condensed and, in most cases, recycled. 
     The most prominent of these processes is a process similar to the theoretical Rankin-cycle, which for simplicity will be referred to in this application as the ‘conventional single-medium-process’. All known ‘conventional single-medium-processes’ that are the present state of the art use only one single closed cycle process with only one single process fluid. All known ‘conventional single-medium-processes’ inherently have loss of the energy of the phase change in common. 
       FIG. 1  shows, as an example of the state of the art, a typical flow-diagram of the most common process, the ‘conventional single-medium-process’. This flow-diagram can be found in many publications in this or a similar form. Note that  FIG. 1  shows the actual process and not an idealised theoretical process—referred to as Rankin cycle. 
     As shown in  FIG. 1 , external thermal energy, shown as an arrow ( 01 ), is inserted from outside the system into the system and process. In heat exchanger ( 02 ) this external thermal energy is used to produce the pressurised gas phase of the process fluid. Arrow ( 03 ) symbolically shows the medium that transported the external thermal energy into the system exiting heat exchanger ( 2 ). In nearly all cases, the gas phase is overheated pressurised steam from water and heat exchanger ( 02 ) is referred to as ‘the boiler’. However, also other process fluids, e.g. refrigerator liquids, can be and are used, but, to a much lesser degree. 
     The overheated vapour of the used process fluid, e.g. steam, contains the energy transferred to it from the external source and streams to an expander ( 04 ). In the expander ( 04 ), which in most cases is a steam turbine, a part of the thermal energy in the process fluid is used to generate kinetic energy, indicated by arrow ( 08 ). The remaining expanded vapour or steam leaves the expander ( 04 ) and goes to the condenser ( 05 ). Condenser ( 05 ) is a heat exchanger in which the expanded gaseous process fluid is cooled and condensed to its liquid state by means of coolant from an external source that enters condenser ( 05 ) at ( 09 ) and exits at ( 10 ). After passing through condenser ( 05 ) liquid process fluid is returned to heat exchanger/boiler ( 02 ) through reservoir ( 07 ) by a pump ( 06 ). 
     During the evaporation of the process fluid in the heat exchanger/boiler ( 02 ) only a part of the introduced external thermal energy is changed into thermal energy that can then be used to generate kinetic energy. A large part of the introduced external thermal energy is needed for and consumed by the phase change of the process fluid from liquid to gas. This part of the energy that enables and sustains the phase change is referred to as “heat of evaporation” or “evaporation enthalpy” and in the past was also called “latent heat”. This large part of the energy consumed by the phase change from liquid to gas is not thermal energy and cannot be used in the expander. 
       FIG. 2  shows the same flow chart as  FIG. 1 . However, in contrast to  FIG. 1 , the arrows that show the flow of the process fluid through the process are split into two parts: a first part that conveys and represents only the thermal energy is shown in lighter shading and a second part that represents only the energy of the phase changes is shown in darker shading. For example, the amount of thermal energy that enters expander ( 04 ) from boiler ( 02 ) is shown as arrow ( 22 ) and the thermal energy exiting expander ( 04 ) is shown as arrow ( 25 ). 
     Additionally, the temperatures in degrees Centigrade are shown in small tables attached to the specific parts of the process. Percentages of the energies relative to the introduced primary energy at the beginning at ( 01 ) are shown as numbers at each of the arrows indicting the parts through the ‘conventional single-medium-process’ using water as the process fluid. The energy numbers in kJ, as well the percentages are the amount of additionally introduced energy at ( 21 ) and do not contain the energy that may be already in the system or in the substances or media, when it operates above absolute zero degrees Kelvin. 
     The percentages in  FIG. 2  relate to a ‘conventional single-medium-process’ at an entrance temperature of steam to the heat exchanger ( 02 ) of around 600° Centigrade, which is a commonly used temperature range at which the ‘conventional single-medium-process’ uses about 60% of the primary energy that is introduced into the process in the boiler for the phase change from liquid water to gaseous steam. The numbers shown in  FIG. 2  can change from case to case because the pressure used in the system can change from application to application. The range of the percentages however is within realistic numbers, even on the high side, as most existing plants actually have an even higher percentage of the primary input energy used for the phase change of the process fluid from liquid to gaseous state. The energy of the phase changes, i.e. evaporation energy ( 23 ) and condensation energy ( 26 ) passes through the ‘conventional single-medium-process’ or system until it is then released at the condenser ( 05 ). 
     The condenser ( 05 ) is a heat exchanger where the process fluid in the form of expanded steam meets a colder medium ( 09 ) that is used for the condensation. In most cases external ambient air or external nearby water are used as the second medium in the heat exchange of the condenser ( 05 ). The energy of the phase changes ( 27 ) is then transferred in most cases to the surrounding without any use inside the ‘conventional single-medium-process’. 
     In  FIG. 1  at ( 08 ) and in  FIG. 2  at ( 24 ) the ‘primary kinetic energy’ is shown as an arrow. This ‘primary kinetic energy’ can only be recovered completely if the expander can change all of the ‘primary kinetic energy’ onto its output, for example at a shaft that drives an electric generator. Usually there are further losses due to the mechanical efficiency of the expander ( 04 ) so that the output of kinetic energy is lower than the ‘primary kinetic energy’ that a process is producing. Additionally the power for the used pumps and compressors needs to be subtracted from this ‘primary kinetic energy’. 
     If, in the exact same ‘conventional single-medium-process’ as shown and explained in  FIG. 2 , the temperature of the external medium entering at ( 01 ), is 200° (two hundred degrees) Centigrade, thus introducing around 2,200 kJ of available energy for the process per kg steam, then approximately 95% (ninety five percent) of the available external primary energy introduced into the process in heat exchanger/boiler ( 02 ) is consumed for the phase change from liquid water to gaseous steam. This would amount to approximately 2,090 kJ. This approximately 95% of the primary energy cannot be used in the ‘conventional single-medium-process’, which comprises no means for utilizing it. For the ‘conventional single-medium-process’ this energy is lost and only 5% of the primary external energy fed into the system is additional thermal energy that can be used. In  FIG. 2  this energy is shown at ( 22 ) but for the higher energy input at 600° C. 
     In the ‘conventional single-medium-process’ the steam leaves the expander before it is condensed. Therefore there is some thermal energy left in that part of the process. This is shown in  FIG. 2  at ( 25 ). 
     In case of the example with exactly the same ‘conventional single-medium-process’ but with 200° C. input, the expanded steam would leave the expander ( 04 ) as part of the process ( 25 ) at 120° Centigrade and thus with less than 32 kJ per kg steam. This thermal energy which has not been converted to ‘primary kinetic energy’ inside the expander ( 04 ) counts about 1.4% relative to the primary energy input at the beginning of the system of the ‘conventional single-medium-process’. Thus the possible conversion of primary energy to primary kinetic energy with the ‘conventional single-medium-process’ at 200° Centigrade cannot be more than 3.6% (three point six percent)! These numbers explain and present clearly why a ‘conventional single-medium-process’ is not suited for the utilisation of low temperature heat sources—the efficiency based on the fed external energy as primary energy would be incredibly low. Even if other numbers that are freely available for the energy content of steam at different temperatures are chosen as the base of such calculations, the results might be slightly different but would remain in the same range. 
     The ‘conventional single-medium-process’ and other existing and or known processes that extract kinetic energy from external thermal energy based on the changes of volume connected to the change of phase from liquid to gas and vice versa, exclusively consider thermal and kinetic energy. Accordingly these ‘conventional single-medium-processes’ are not designed to use or recover the energy of the phase change of the process fluid. Any additional use or recovery of the energy of the phase change of the process fluid is dependent on overcoming the following physical restrictions and/or limitations:
         Firstly, thermal energy can only be transferred as thermal energy from a mass with higher temperature to a mass with lower temperature. If and when energy were to be recovered as thermal energy from the condensation of the process fluid (after physical work has been done to extract kinetic energy) then this thermal energy can only be on a temperature level below the temperature of condensation of the process fluid. At this temperature level it is physically not possible to transfer this energy directly back into the single-medium-process. (This is also referred to as limitation of the Second law of Thermodynamics.)   Secondly, if the recovered thermal energy from the condensation of the process fluid were transferred back into the process fluid of the single-medium-process before heating the process fluid of the single-medium-process, in  FIGS. 1 and 2  at heat exchanger ( 02 ), then the process fluid would be heated in nearly all cases to a temperature level close to the temperature with which the external energy will be introduced into the single-medium-process. This is due to the amount of energy, for example measured in kilo Joule, that would lead to a temperature that corresponds with the amount of transferred kilo Joules and that would be in most cases close to the entrance temperature of the energy introduced from outside into the system of the ‘conventional single-medium-process’, in  FIGS. 1 and 2  at ( 02 ). Therefore, even if it were possible to recover the energy of the condensation as thermal energy and transfer it back into the process fluid of the ‘conventional single-medium-process’, it would increase the temperature of the process fluid and thus minimise the temperature difference between the external thermal energy from the outside source ( 01 ) trying to introduce thermal energy into the system and the temperature of the process fluid of the ‘conventional single-medium-process’ entering the heat exchanger or boiler ( 02 ). This would in turn lead to exhaust temperatures of the boiler, i.e. exit temperatures of the heat exchanger ( 02 ) that are significantly higher than with the usual temperature difference of the process fluid of the single-medium-process entering the boiler ( 02 ), and the medium used to introduce thermal energy into the system or process without this recovery of energy. The temperature of the medium delivering the external thermal energy to heat exchanger ( 02 ) would then be, when leaving heat exchanger ( 02 ), shown in  FIGS. 1 and 2  as arrow ( 03 ), higher than the stream of energy that would deliver the energy recovered from the condensation. Therefore the external medium would leave heat exchanger ( 02 ) still containing a large amount of thermal energy that could not be transferred into the process fluid of the ‘conventional single-medium-process’. The energy gained from recovering thermal energy from the condensation would be balanced by the losses caused by the decreased temperature-difference at the boiler or heat exchanger ( 02 ). Because thermal energy is transferred in conjunction with some mass, heat losses and some mechanical losses occurring during forwarding this interrelated mass could not be avoided and would thus further decrease the recovered thermal energy. The outcome would most likely even be negative. i.e. more energy would be lost than could be recovered due to losses of the additional steps for recovering and reusing the energy of the phase change.   Thirdly, it is also not possible in a ‘conventional single-medium-process’ to first introduce the external thermal energy from outside of the process ( 01 ) then to heat the process fluid of the ‘conventional single-medium-process’ with this external energy and then after heat exchanger ( 02 ) to heat the already heated process fluid of the single-medium-process further with the recovered thermal energy from the condensation. The external thermal energy that is introduced into the process fluid of the ‘conventional single-medium-process’ at heat exchanger ( 02 ) leads to an increase of temperature and therefore another extra increase of temperature to the same temperature level through another heat-source is physically not possible. In a ‘conventional single-medium-process’ two thermal energies cannot be introduced at a similar temperature level into the process fluid of the ‘conventional single-medium-process’. In much simpler words: it is not possible to heat a process fluid that is already at 500° Centigrade with another heat source at 500° Centigrade to a temperature above 501° Centigrade—that would defy physics.       

     It is therefore a purpose of the present invention to provide a system and process for converting thermal into kinetic energy that overcomes the above-described physical restrictions and/or limitations to allow recovery of the energy of the phase change of the process fluid. 
     It is another purpose of the present invention to provide a system and process for converting thermal into kinetic energy that provides process efficiencies in all temperature ranges that are significantly higher than in any other processes known today. 
     Further purposes and advantages of this invention will appear as the description proceeds. 
     SUMMARY OF THE INVENTION 
     In a first aspect the invention is a complete process to transfer thermal energy into kinetic energy. The complete process comprises:
         A) a work process in which a work process fluid circulates in a closed cycle through components of an energy transformation system. In part of the closed cycle the work process fluid is divided such that it flows in two parallel work process streams. In part of the closed cycle the two parallel work process streams are joined and the work process fluid flows in a single combined work process stream; and   B) an energy transfer process in which an energy transfer process fluid circulates in single energy transfer stream in a closed cycle through components of the energy transformation system.       

     The following four processes are carried out simultaneously for each of the streams: 
     i) for a first work process stream:
         a) sucking a first specific part of the work process fluid in its liquid state below its boiling temperature out from a reservoir;   b) pressurising the first specific part of the work process fluid to a specific pressure, which is at least as high as the highest pressure in the following steps of the work process;   c) causing the pressurised first specific part of the work process fluid to pass through a first heat exchanger and to receive thermal energy from the energy transfer process fluid of the energy transfer process, wherein the received thermal energy originates from within the energy transfer process;   d) causing the pressurised first specific part of the work process fluid to exit the first heat exchanger still in its liquid state but with increased temperature;   e) causing the pressurised first specific part of the work process fluid to pass through at least one valve mechanism configured to prevent premature evaporation of the heated work process fluid;   f) causing the pressurised first specific part of the work process fluid still in liquid state to enter an expansion chamber of an expander;   g) causing the pressurised first specific part of the work process fluid to flash evaporate, thus changing into a gaseous state with a specific pressure inside the expansion chamber, thereby converting at least a part of the thermal energy received in the first heat exchanger into kinetic energy;
 
ii) for a second work process stream:
   a) sucking a second specific part of the work process fluid in its liquid state below its boiling temperature out from the reservoir;   b) pressurising the second specific part of the work process fluid to a specific pressure which is at least as high as the highest pressure in the following steps of the work process;   c) causing the pressurised second specific part of the work process fluid to pass through a second heat exchanger and to receive thermal energy from an external energy source;   d) causing the pressurised second specific part of the work process fluid to exit the second heat exchanger still in its liquid state but with increased temperature;   e) causing the pressurised second specific part of the work process fluid to pass through at least one valve mechanism configured to prevent premature evaporation of the heated work process fluid;   f) causing the pressurised second specific part of the work process fluid still in liquid state to enter the expansion chamber of the expander;   g) causing the pressurised second specific part of the work process fluid to flash evaporate, thus changing into a gaseous state with a specific pressure inside the expansion chamber, thereby converting at least a part of the thermal energy received in the second heat exchanger from the external energy source into kinetic energy;
 
iii) for the combined work process stream
   a) causing the evaporated and expanded gas phase of the first and second specific parts of the work process fluid to exit the expander via an outlet mechanism;   b) causing the evaporated and expanded gas phase of the first and second specific parts of the work process fluid to flow from the outlet mechanism into a third heat exchanger and to exchange thermal energy with colder energy transfer process fluid in the energy transfer process;   c) causing the first and second specific parts of the work process fluid to exit the third heat exchanger in the liquid state at their lowest temperature and pressure in the work process;   d) causing the first and second specific parts of the work process fluid to enter the reservoir;
 
iv) for the energy transfer stream;
   a) causing energy transfer process fluid in the gaseous state at its lowest temperature to enter the third heat exchanger in the energy transfer stream and to exchange thermal energy with work process fluid at a higher temperature in the combined work process stream;   b) causing the energy transfer process fluid in the gaseous state to be sucked out of the third heat exchanger with its temperature elevated by absorption of the condensation energy of the work process fluid;   c) causing the energy transfer process fluid to be pressurized, thereby further increasing its temperature;   d) causing the energy transfer process fluid to enter the first heat exchanger at its highest temperature in the energy transfer stream and to exchange thermal energy with colder liquid phase work process fluid of the first work process stream;   e) causing the cooled energy transfer process fluid still in the gaseous state to exit the third heat exchanger;   f) causing the cooled energy transfer process fluid still in the gaseous state to go through a decompression step, thereby further decreasing its temperature of the energy transfer process fluid, by passing through a section of a conduit wherein the cross section of the conduit is increasing;
 
v) cyclically repeating the steps of paths i) to iv).
       

     In embodiments of the process the energy transfer process receives all of the freed energy of the condensation of the process fluid of the work process. 
     In embodiments of the process the energy transfer process transfers all of the freed energy of the condensation of the process fluid of the work process back into the work process. 
     In embodiments of the process the first work process stream and the second work process stream share the same valve mechanism and pass through the valve mechanism to the expansion chamber of the expander together. 
     In embodiments of the process at least one additional heat exchanger further cools the energy transfer process fluid after the energy transfer fluid passes through the first heat exchanger by transferring thermal energy from the energy transfer process fluid to at least one process fluid flowing in at least one process external to the work process and energy transfer process of the complete process. 
     In embodiments of the process at least one additional expander decreases further the remaining pressure of the energy transfer process fluid after the energy transfer fluid passes through the first heat exchanger thus transforming at least a part of the pressure into available kinetic energy at the mechanical outlet of the expander. 
     In a second aspect the invention is a system for carrying out the complete process of the first aspect for transferring thermal energy into kinetic energy. The system comprises the following components:
         a) a reservoir comprising liquid work process fluid;   b) a first pump;   c) a first heat exchanger;   d) at least one valve mechanism;   e) an expansion chamber of an expander   f) conduits connecting components a) to e) to comprise a path for work process fluid of a first work process stream from the reservoir to the expander;   g) a second pump   h) a second heat exchanger   i) conduits connecting components a), g), h), d), and e) to comprise a path for work process fluid of a second work process stream from the reservoir to the expander;   j) an outlet mechanism;   k) a third heat exchanger;   l) conduits connecting components e), j), k), and a) to comprise a path for work process fluid of a combined work process stream from the expander to the reservoir;   m) a compressor; and   n) conduits connecting the third heat exchanger to the compressor, the compressor to the first heat exchanger, and the first heat exchanger to the third heat exchanger to comprise a closed path for energy transfer process fluid of an energy transfer stream.       

     In embodiments of the system at least one additional heat exchanger further cools the energy transfer process fluid after the energy transfer fluid passes through the first heat exchanger by transferring thermal energy from the energy transfer process fluid to at least one process fluid that flows in at least one process external to the work process and energy transfer process of the complete process. 
     Embodiments of the system comprise at least one additional heat exchanger in the energy transfer stream, that is configured to further cool the energy transfer process fluid after the energy transfer fluid passes through the first heat exchanger by transferring thermal energy from the energy transfer process fluid to at least one process fluid carrying thermal energy from an external energy source that flows into a heat exchanger connected before the second heat exchanger thus increasing the temperature of the at least one process fluid carrying thermal energy from the external energy source before it reaches the second heat exchanger. 
     Embodiments of the system comprise at least one additional expander in the energy transfer stream that is configured to decrease the pressure of the energy transfer process fluid after the energy transfer fluid passes through the first heat exchanger thus transforming at least a part of the pressure into available kinetic energy at the mechanical outlet of the expander. 
     In embodiments of the system the first work process stream and the second work process stream share the same valve mechanism and pass through the valve mechanism to the expansion chamber of the expander together. 
     In embodiments of the system the valve mechanism before the expander is configured to operate in a clocked fashion to prevent premature evaporation of the work process fluid before it enters the expander. 
     In embodiments of the system the valve mechanism before the expander is configured as a lock mechanism to prevent premature evaporation of the work process fluid before it enters the expander. 
     In embodiments of the system the valve mechanism before the expander is configured as a metering mechanism to prevent premature evaporation of the work process fluid before it enters the expander and to allow exactly metered amounts of the work process fluid to be released into the expansion chamber. 
     In embodiments of the system the metering mechanism is a metering rotating valve mechanism. 
     In embodiments of the system at least one of the pumps or the compressor are connected to the expander either by a direct or indirect mechanical, hydraulic, pneumatic, or electrical connection in a way that at least a part of the kinetic energy provided by a mechanical outlet of the expander at least partly provides the necessary kinetic energy for operation of the at least one of the pumps or compressors. 
     In embodiments of the system at least one of the pumps or the compressor of the system is connected to an additional expander in the energy transfer stream either by a direct or indirect mechanical, hydraulic, pneumatic, or electrical connection in a way that at least a part of the kinetic energy provided by a mechanical outlet at least partly provides at least some of the necessary kinetic energy for operation of the at least one of the pumps or compressors. 
     In embodiments of the system the speed of the work process and the energy transfer process can be adjusted relative to each other, with a different relative speed of the pumps of the work process compared to the compressor of the energy transfer process. 
     In embodiments of the system the cross section of the components through which the process fluids are moving are configured in such a way that the flow speeds and flow pattern of the process fluids at specific locations at which thermal energy in the process fluids is either increased or decreased, thereby changing the temperature of the process fluids, are optimised and thus energy losses reduced. 
     All the above and other characteristics and advantages of the invention will be further understood through the following illustrative and non-limitative description of embodiments thereof, with reference to the appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a flow chart that shows a typical prior art process that transform external thermal energy in a process fluid into kinetic energy; 
         FIG. 2  shows the same flow chart as  FIG. 1  the flow of the process fluid through the process split into a first part that represents the thermal energy and a second part that represents the energy of the phase changes, also shown are parameters related to the flow of the process fluid at various locations; 
         FIG. 3  shows the complete process and system of the invention in the form of a schematic flow diagram; 
         FIG. 4  shows the first work stream of the complete process and system of the invention in the form of a schematic flow diagram; 
         FIG. 5  shows the second work stream of the complete process and system of the invention in the form of a schematic flow diagram; 
         FIG. 6  shows the energy transfer stream of the complete process and system of the invention in the form of a schematic flow diagram; 
         FIG. 6 a    shows the same flow diagram as  FIG. 6  with the addition of one additional expander shown in darker shading; 
         FIG. 7  shows the same flow diagram as  FIG. 6  with the addition of two additional heat exchangers; 
         FIG. 7 a    shows the same flow chart as  FIG. 7  with only one of the two additional heat exchangers connected to an additional optional heat exchanger in the stream of external energy entering the complete process; 
         FIG. 8  shows the same flow diagram as  FIGS. 3 to 7  with the stream of external energy into the complete process shown in darker shading; and 
         FIG. 9 ,  FIG. 10 , and  FIG. 11  show the flow chart of  FIG. 3  with tables showing parameters related to the state of the flow of the process fluid at various locations. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     The present invention combines interacting main processes and sub-processes to extract kinetic energy from thermal energy. These different interacting processes and sub-processes are physically separate from each other with the main processes operating as closed cycles that operate with two different process fluids parallel to each other and interact with each other, in order to consider and utilize sufficiently all three forms of energy, i.e. thermal energy, kinetic energy, and the energy of the phase changes. By interacting, these different main processes and sub-processes enable a ‘combined-process’ that especially allows the highly efficient transformation of low temperature thermal energy into kinetic energy. Unique and outstanding features of the combined process of the invention are an artificial heat sink, the recovery and conservation of the condensation enthalpy in one of the sub-processes, and keeping all thermal energy inside the combined process. With the combined process even sub-zero temperatures can be used with high efficiency as heat sources. Additionally, the independence of the overall efficiency of transforming thermal energy into kinetic energy from the operating temperatures is significantly increased. For energy conservation and the environment the advantages of this invention are great. 
     In its minimal form that ensures that it can work orderly the process of the invention is comprised of two main processes that define separate streams for transferring energy that both operate as closed cycles parallel to each other. All processes together are referred to as the ‘complete process’. The following description and figures show for each component, part, process, or sub-process only the required minimum number that can allow orderly operation of the system. 
     It is always possible to increase the number of functional components, or streams and let those work in parallel in a similar way that, for example, in a piston engine several cylinders, pistons, or the number of valves or spark plugs per cylinder could be increased; all nevertheless still operating under the same principle, which would be described only with the minimum number of each item necessary for complete functionality. 
       FIGS. 3-11  are flow diagrams showing the flow of process fluid around the system. As such the figures are used to interchangeably describe both the process of the invention and the physical components of the system of the invention in which the process is carried out. 
       FIG. 3  shows the complete process and system ( 100 ) of the invention in the form of a schematic flow diagram. In  FIG. 3  a work process ( 110 )—known in the system as work stream ( 110 )—is shown in darker shading and an energy transfer process ( 120 )—known in the system as energy process stream ( 120 )—in lighter shading. For some steps the work process ( 110 ) divides into two parallel sub-processes—first work stream ( 150 ) and second work stream ( 140 ). Only the work process ( 110 ) generates kinetic energy out of physical work. The paths of the processes and sub-processes are shown with arrows. 
     In the embodiment shown in  FIG. 3  the first work stream ( 150 ) and second work stream ( 140 ) separate at the small reservoir ( 41 ) and reunite before the valve mechanism ( 45 ) at the point ( 44 ) after the heat exchangers ( 43 ) and ( 53 ). This section of work stream ( 110 ) operates as a closed cycle in the following way: In a small reservoir ( 41 ) is a first process fluid in its liquid state for both parallel partial streams. This process fluid that circulates in both parallel partial streams of the closed work stream is referred to herein as the work stream process fluid. The work stream process fluid could be water or another substance, for example with a significantly lower boiling temperature than water in order to utilise thermal energy with low temperature Example for two suitable process fluids are monochlorodifluor-methane (used for the calculation of  FIG. 11 ) or methoxy-ethane or di-nitro-tetra-oxide; Both, the first and the second partial streams of the work stream ( 110 ) move separated, parallel to each other, until they pass through the first heat exchanger in their separate paths until point ( 44 ). For the first parallel partial stream ( 150 ) this is heat exchanger ( 43 ) and for the second parallel partial stream ( 140 ) this is heat exchanger ( 53 ). 
       FIG. 4  schematically shows the first work stream ( 150 ) in dark shading. The first work stream ( 150 ) functions as follows: Using a first pump ( 42 ) a specific amount of work stream process fluid that is in liquid state is sucked out of the small reservoir ( 41 ), pressurised and pumped through heat exchanger ( 43 ). At the small reservoir ( 41 ) the work stream process fluid has the lowest temperature in the complete process. The amount of the cold, liquid work stream process fluid that is pumped out of the small reservoir ( 41 ) and used in the first work-stream ( 150 ) depends on the total amount of the work stream process fluid in the complete work process ( 110 ) and on the amount of energy that needs to be transferred in heat exchanger ( 43 ). Several sample calculations are provided herein below. 
     In heat exchanger ( 43 ) the pressurised, liquid, cold work stream process fluid is pressed forward by pump ( 42 ) and is heated up by the gaseous hot process fluid of the parallel operating energy transfer process ( 120 ) that will be described herein below. Heat exchanger ( 43 ) transfers thermal energy into the work stream process fluid from the energy transfer stream process fluid that enters heat exchanger ( 43 ) in the most efficient form from the opposite side. To this end the energy transfer stream process fluid was heated up and the liquid work stream process fluid has at its entrance to heat exchanger ( 43 ) still its coldest temperature in the first work stream. 
     In nearly all but some extreme cases the first of the two parallel work streams is heated to a much higher temperature than the second of the two parallel work streams. The pressure applied by pump ( 42 ) prevents this specific part of the work stream process fluid from starting to evaporate after being heated in heat exchanger ( 43 ). The energy that is transferred in heat exchanger ( 43 ) from the energy transfer stream process fluid into the work stream process fluid corresponds to the energy that is transferred during the condensation process into the energy transfer stream process fluid. 
     The work stream process fluid has the highest temperature it can reach in the first work stream ( 150 ) at this point when leaving heat-exchanger ( 43 ) before entering the valve mechanism ( 45 ). 
     The valve mechanism ( 45 ) has the main task of preventing the overheated, pressurised work stream process fluid from evaporation before it is inside the expansion-chamber ( 46 ) of the expander. The valve mechanism ( 45 ) also controls the flow-speed of the work stream process fluid in order to prevent a part of the hot work stream process fluid to increase speed and prematurely start evaporating. An advantageous way to realise controlling valve ( 45 ) is by using it as a lock system that disrupts fluid communication between the amount of work stream process fluid that is entering the expansion chamber ( 46 ) of the expander and the work stream process fluid that is still before valve mechanism ( 45 ). Another advantageous embodiment of the valve mechanism ( 45 ) is a metering mechanism, e.g. a rotating valve mechanism. If valve mechanism ( 45 ) causes a clocked or pulsed performance this would not pose any disadvantage for the process. For orderly operation the valve mechanism ( 45 ) and pump ( 42 ) need to be adjusted to or harmonised with each other. 
     When the overheated, pressurised work stream process fluid passes through the valve mechanism ( 45 ) and enters the expansion chamber ( 46 ) it immediately flash evaporates due to the increased cross section of the expansion chamber ( 46 ). The expander can be any kind of expander that either works with positive replacement or a fluid mechanical mechanism to generate a movement from the pressure difference of the flash work stream process fluid at the entrance and the exit of the expansion chamber ( 46 ). An advantageous embodiment of the expansion chamber is an engine that operates with positive replacement and can handle condensation and the formation of drops inside the expansion chamber. It is also possible to use a pre-chamber for the flash-evaporation as is known from turbines that work with super-critical steam. For the complete-process ( 100 ) the design of the expansion chamber ( 46 ) is not important. 
     During the flash evaporation in the expansion chamber ( 46 ) the overheated, pressurised work stream process fluid of both parallel work streams of the work process ( 110 ) consumes a specific amount of thermal energy to enable the phase change from the liquid state to the gaseous state and the temperature of the work stream process fluid drops to a lower temperature. In most cases this energy consumed for the phase change will be the largest part of the thermal energy contained in the work stream process fluid. The remaining thermal energy of the now gaseous work stream process fluid applies a certain pressure in the expansion chamber that is then converted to kinetic energy. In  FIGS. 3 to 11  this is shown as a schematic piston ( 47 ). 
     When the work stream process fluid is expanding, thus converting thermal energy into kinetic energy, and has reached the furthest point in expansion chamber ( 46 ), an outlet mechanism ( 48 ) connects the now expanded gaseous work stream process fluid to the following condenser ( 49 ). The outlet mechanism from the expansion chamber ( 48 ) to the condenser ( 49 ) can be an opening, a special valve or an outlet mechanism as described in patent application WO/2013072913 A1 to the inventor of the present invention. 
     The condenser ( 49 ) works as a heat exchanger. One medium is the work stream process fluid that circulates in the closed work process ( 110 ). The other medium going through heat exchanger ( 49 ) is the gas of the other closed main process, i.e. the energy transfer process ( 120 ). When entering heat exchanger ( 49 ) the gas of the energy transfer process ( 120 ) is significantly colder than the work stream process fluid. 
     The main task of the heat-exchanger ( 49 ) is to transfer energy from the expanded work stream process fluid to the energy transfer stream process fluid so that the work stream process fluid condenses and turns into its liquid state. The energy that has to be removed from the work stream process fluid to bring about the complete condensation of the work stream process fluid leads to a decrease of temperature of the work stream process fluid and an increase of temperature of the energy transfer stream process fluid. 
     The cooled, liquid unpressurised work stream process fluid flows then from the condenser ( 49 ) to the reservoir ( 41 ) and the same cycle for the first work stream ( 150 ) is repeated. 
       FIG. 5  schematically shows the second work stream ( 140 ) in dark shading. The second work stream ( 140 ) functions as follows: A second pump ( 51 ) sucks a specific amount of the cold work stream process fluid out of the small reservoir ( 41 ), pressurises, and pumps it directly to heat exchanger ( 53 ). The amount of the cold work stream process fluid that is pumped out of the small reservoir ( 41 ) and used in the second work-stream depends on the amount of the complete work stream process fluid in the complete process and on the amount of energy that needs to be transferred in heat exchanger ( 53 ). Several sample calculations are provided herein below. 
     As can be seen in  FIG. 5 , this second work-stream ( 140 ) does not go through heat-exchanger ( 43 ). The thermal energy for heating the work-stream-medium in heat exchanger ( 53 ) comes from outside the process. Heat exchanger ( 53 ) is thus the entrance point for external thermal energy entering the complete process or system. The entrance of the external thermal energy from outside into heat exchanger ( 53 ) is described further below. This introduced external thermal energy determines the temperature that can be reached at heat exchanger ( 53 ). If the amount of energy needed for the phase change of the work stream process fluid is higher than the amount of external energy that is introduced into the complete process, than the highest temperature that the work stream process fluid can reach at its entrance to heat exchanger ( 53 ) is lower than the temperature that is reached at its exit from heat exchanger ( 43 ). 
     The work stream process fluid of the second work stream ( 140 ) is heated without evaporating in heat exchanger ( 53 ) and released through a special valve mechanism ( 45 ) into the expansion chamber ( 46 ) of the expander. The work stream process fluid of the second work stream ( 140 ) flash evaporates only in the expansion chamber ( 46 ). In the embodiment shown in  FIGS. 3 to 8  both parallel partial work streams are mixed before the valve mechanism ( 45 ) and flash evaporate together as one stream. 
     Both, the first work stream and the second work stream move separated and parallel to each other until each stream has passed through its first heat exchanger. For the first work stream this is heat exchanger ( 43 ) for the second work stream this is heat exchanger ( 53 ). After they have each passed their respective first heat exchanger, both streams can be merged into one stream at any given point until the work stream process fluid flash evaporates and changes from the liquid phase into the gas phase inside the expansion chamber ( 46 ). It is technically advantageous if both partial streams of the work-stream meet before the valve mechanism ( 45 ) because then only one single valve mechanism is required. Otherwise this does not change the complete process ( 100 ) and/or the work process ( 110 ). 
     By splitting the work stream ( 110 ) into two parallel partial streams, it is possible to heat them independently and parallel to each other. The first work stream ( 150 ) receives the energy of the condensation of the work stream process fluid and thus keeps this energy inside the complete process ( 100 ). For the energy balance of the complete process ( 100 ) and for its efficiency this is of great importance. The second work stream ( 140 ) receives the external thermal energy that is introduced into the system from outside. By transferring the energy in parallel and not sequential or successively, both the first and second work processes can receive the complete amount of energy that is supposed to be transferred to each of them. Both parallel partial streams have at the beginning of the transfer of energy their lowest temperature in the work process ( 110 ) and the complete process ( 100 ), thus providing the ability to use the maximum temperature difference for the transfer of thermal energy. 
     Because the evaporation is not supposed to happen before either of the first or second work streams have reached the expansion chamber ( 46 ), it is possible that either one or both of them reach a temperature where the work stream process fluid is in a super-critical state. This has no process changing influence, neither on the task of the work process nor on the complete process. 
     Both parallel work streams mix with each other after they have received energy respectively in the heat exchangers ( 43 ) and ( 53 ). This mixing of both parallel work streams will lead to an average temperature that is lower than the temperature of the stream that had the higher temperature. However, this does not lead to a loss of energy because the combined streams still contain the exact same amount of energy (e.g. in kilo Joule) as the sum of the two parallel partial streams. 
       FIG. 6  is a schematic flow diagram showing the energy transfer stream ( 120 ) of the complete process and system ( 100 ) of the invention in darker shading and the rest of the complete process in lighter shading. The flow speed of the energy transfer stream can be different than the flow speed of the work stream. 
     The energy transfer stream uses a gas, e.g. carbon-dioxide and methane, as a medium referred to as the “energy transfer stream process fluid”. The main task out of several tasks of the energy transfer stream is to keep the energy which is extracted during condensation of the work stream process fluid inside the complete process. To this end the energy transfer stream process fluid streams into heat exchanger ( 49 ) with the coldest temperature the energy transfer stream process fluid has during the energy transfer process. In heat exchanger ( 49 ) thermal energy plus the energy related to the condensation is transferred from the nearly completely expanded work stream process fluid in its gaseous state with a temperature close to its condensation temperature into the energy transfer stream process fluid that has at the entrance of heat exchanger ( 49 ) its lowest temperature and its lowest pressure within the energy transfer stream. The energy transfer stream process fluid thus increases its temperature inside heat-exchanger ( 49 ) by the energy extracted from the work stream process fluid that is the second stream in heat-exchanger ( 49 ) and in turn the work stream process fluid condenses as a result of the extraction of energy. 
     When the energy transfer stream process fluid is extracting energy from the condensation of the work stream process fluid in heat exchanger ( 49 ) the energy related to the condensation of the work stream process fluid is transferred to the energy transfer stream process fluid at a low temperature level compared to the temperatures at other points of the complete process. The amount of the energy transfer stream process fluid has to be chosen accordingly to be able to absorb this energy in the form of thermal energy. The most advantageous amount of the energy transfer stream process fluid in the energy transfer stream is therefore determined by the ability to absorb the total energy freed during the condensation of the work stream process fluid. The energy that needs to be absorbed expressed in kilo Joule divided by the possible temperature increase in degrees Kelvin by the following compression in compressor ( 72 ), the heat capacity of the specific energy transfer stream process fluid at the different chosen temperatures, and relative flow speed of the energy transfer stream process fluid compared to the flow speed of the work stream process fluid gives the minimum mass and thus the minimum amount of gas that is needed for the energy transfer stream in order to be able to extract all of the energy related to the condensation from the work-stream. Several sample calculations herein below will explain this in more details. 
     Heat-exchanger ( 49 ) is followed in the energy transfer stream by compressor ( 72 ). The heated energy transfer stream process fluid is sucked into and compressed by compressor ( 72 ) to higher pressure and higher temperature. 
     Compressing the energy transfer stream process fluid in compressor ( 72 ) to a specific higher temperature allows then, in a following step, the transfer of this energy from the condensation back through heat exchanger ( 43 ) into the work stream process fluid in the first work stream ( 150 ). The thermal energy transferred from the energy transfer stream process fluid to the first work stream at heat exchanger ( 43 ) is used in the work stream ( 110 ) to support the evaporation of the complete work stream process fluid not just the process fluid of the first work stream. According to the amount of energy that needs to be transferred, the temperature of the energy transfer stream process fluid after compressor ( 72 ) needs to be sufficiently high enough to enable the transfer of a sufficient amount of thermal energy into the work stream process fluid of the first work stream ( 150 ). The exact temperature increase that the energy transfer stream process fluid needs to reach in compressor ( 72 ) is given by the amount of energy that needs to be transferred in kilo Joule, divided by the mass per time and the specific heat capacity of the energy transfer stream process fluid and the relative flow speed of the energy transfer stream process fluid compared with the flow speed of the work stream process fluid. 
     This step of elevating the energy of the condensation extracted from the work stream process fluid to a higher temperature level by compressing the energy transfer stream process fluid is only possible in a separate process and also only with a different process fluid than those of the work stream. 
     Leaving compressor ( 72 ) the pressurised and hot energy transfer stream process fluid enters the heat-exchanger ( 43 ). After the compression the energy transfer stream process fluid has at this location its highest temperature in the energy transfer stream. Inside heat exchanger ( 43 ) the pressurised and hot energy transfer stream process fluid exchanges thermal energy with the pressurised liquid work stream process fluid which enters heat exchanger ( 43 ) at its coldest temperature in the first work stream. Both the work stream process fluid and the energy transfer stream process fluid exchange thermal energy, thereby increasing the temperature of the work stream process fluid and lowering accordingly the temperature of the energy transfer stream process fluid. 
     The now cooler energy transfer stream process fluid leaves heat exchanger ( 43 ) and streams either directly to heat exchanger ( 49 ) or in other embodiments through one or several additional heat exchangers or through one or several additional expanders.  FIG. 7  shows the same flow diagram as  FIG. 6  with the addition of two additional heat exchangers. In  FIG. 7  all parts of the complete system ( 100 ) are shown in light shading except for the two additional heat exchangers that are shown in darker shading. These two additional heat exchangers ( 83 ), ( 84 ), extract additional thermal energy from the energy transfer stream ( 120 ). As a consequence the temperature of the energy transfer stream process fluid is further decreased. In case that the source of the external thermal energy of heat exchanger ( 53 ) is generated with the help of a device like a burner where compounds react and release thermal energy, heat exchanger ( 83 ) could heat the oxidiser, for example air used, in the burner and the following heat exchanger ( 84 ) could utilize the remaining thermal energy in the energy transfer stream process fluid to heat partially decompressed fuel gas used in the burner. 
     In case that instead of an oxidiser or fuel gas for a burner another medium is used as source of external thermal energy, especially a source with relative low temperature, thermal energy can be transferred from the additional heat exchanger ( 83 ) to an optional additional heat exchanger ( 86 ) in the incoming stream of external energy (see  FIG. 7 a   ). With the addition of at least one additional heat exchanger ( 83 ), the energy transfer stream process fluid is further cooled whereby the exchanged and/or extracted energy stays within the complete process ( 100 ). Thus the cooling of the energy transfer stream process fluid does not lead to any loss of energy for the complete process or system. 
     In other embodiments the now cooler energy transfer stream process fluid leaves heat exchanger ( 43 ) and streams through at least one additional expander ( 85 ), where at least part of the remaining energy in form of the remaining pressure of the pressurised energy transfer stream process fluid is converted to kinetic energy at the mechanical outlet of the expander that can be used, e.g. in the complete process ( 100 ) or parts of it, e.g. compressor ( 72 ).  FIG. 6 a    shows the same flow diagram as  FIG. 6  with the addition of the additional at least one expander ( 85 ). In  FIG. 6 a    all parts of the complete system ( 100 ) are shown in light shading except for the at least one additional expander ( 85 ) that is shown in darker shading. 
     In other embodiments at least one additional heat exchanger ( 83 ) and together at least one additional expander ( 85 ) are used in at least one of the energy transfer stream processes. 
     Cooling the energy transfer stream process fluid also decreases its pressure. It is therefore advantageous to increase and/or decrease accordingly the cross sections of the paths, for example pipes, in the system followed by the energy transfer stream process fluid in order to keep pressure losses at a minimum. After the energy transfer stream process fluid has passed through heat exchanger ( 43 ) (and optionally) additional heat exchangers ( 83 ), ( 84 ), and/or expander ( 85 ), or additional expanders, the energy transfer stream process fluid arrives at the entrance of heat exchanger ( 49 ). At the entrance of heat exchanger ( 49 ) the energy transfer stream process fluid is going through a decompression. By increasing the cross section of the path (( 117 ), ( 127 ), and  137 ) in  FIGS. 9-11  respectively) through which the energy transfer stream process fluid streams the remaining pressure of the at this point is lowered. At the same time the temperature also decreases. This effect is referred to as decompression effect or as Thomson-Joule effect. This effect is well-known and used in cryo-applications in general and air condition systems in particular. The energy transfer stream process fluid is thus rapidly cooling at the entrance of heat exchanger ( 49 ) and reaches the lowest temperature in the energy transfer stream ( 120 ), which is also the lowest temperature in the complete-process ( 100 ). 
     Through the suction that comes from the compressor ( 72 ) located in the heat transfer stream ( 120 ) right after the heat exchanger ( 49 ) the energy transfer stream process fluid is moved through heat exchanger ( 49 ) and does therefore not require a remaining pressure to overcome the streaming resistance inside heat exchanger ( 49 ). The rapid cooling to a very low temperature constitutes an artificial heat sink in the complete process ( 100 ). As opposed to prior art systems, especially those based on the ‘conventional single-medium-process’ in use since the year 1784 until today, utilize the surroundings, i.e. either the air or some water-body, as the point with the lowest temperature the present invention has its own controllable heat sink as an integral part of the complete process. 
     Like in other cryo-aggregates or cooling devices, the temperature of the heat sink can be chosen to be significantly below ambient temperature, thus creating a temperature difference between the ambient temperature and the lowest temperature within the complete process that can even be used to generate kinetic energy from a source of external thermal energy with ambient temperature of the surroundings. This is even possible if the surrounding ambient temperature is a sub-zero temperature. For such applications both process fluids have to be chosen with the right boiling temperature and the complete process/system needs to be realised with sufficient thermal insulation. Sample calculations herein below show such an example. 
       FIG. 8  shows the same as  FIGS. 3 to 6  except the stream of external energy into the complete process ( 100 ) is shown in darker shading. The external energy that is introduced from outside into the system or into the complete process, enters the process at heat exchanger ( 53 ) as the entrance point of external energy into the ‘complete process’ or system. In nearly all cases the external energy will be thermal energy. In case that heat radiation is used, for example micro waves, instead of external thermal energy the entrance point would still be heat exchanger ( 53 ). In turn heat exchanger ( 53 ) would have a different form for receiving heat radiation and introducing it into the work stream process fluid than in case the external energy is transferred in form of a heated medium. For the complete process ( 100 ) this would not make a difference other than the adaption of the entrance point ( 53 ). 
       FIG. 7 a    shows the same as  FIG. 7  except for the additional heat exchanger ( 86 ) that is connected to the optional heat exchanger ( 83 ) and is in this embodiment used to transfer at least a part of the remaining thermal energy of the energy transfer process ( 120 ) after heat exchanger ( 43 ) into the stream that is introduced from outside into the system or into the complete process. 
     In cases where the external energy that is introduced into the complete process raises the temperature of the second work stream ( 140 ) significantly higher at heat exchanger ( 53 ) than the temperature that the first work stream ( 150 ) reaches after heat exchanger ( 43 ) it would be possible to let the first work stream and the second work stream meet directly at heat exchanger ( 53 ). Then the already heated first work stream would be further heated directly by the external energy at heat exchanger ( 53 ). The same result could also be achieved by dividing heat exchanger ( 53 ) into two regions where the higher temperature region is used by the first work stream ( 150 ) and the lower temperature region is used by the second work stream ( 140 ). However, from an energetic point of view it makes no difference where the energy is transferred or whether the energy is transferred into the complete process ( 100 ) through the first or the second work stream or through both. At the end both streams will eventually mix, either right after the heat exchangers ( 53 ) and ( 43 ) or at the latest inside expansion chamber ( 46 ). Then the two parallel streams of the work stream process fluid will mix together and thus reach a balance between the different temperature levels of thermal energy. What counts for the efficiency of the complete process is how much energy is introduced into the expansion chamber ( 46 ), the different temperatures of the two parallel work streams, however, are not important. The simplest solution, which is shown in  FIGS. 3 to 8 , is therefore also the most advantageous. 
     It could also be advantageous to mechanically connect the expansion chamber ( 46 ) with at least one of the pumps ( 42 ), ( 51 ) and compressor ( 72 ) in order to utilize part of the energy output from the expander to operate these components. Additionally the pumps and compressors could be driven by electro-motors receiving their energy from a generator that is connected to the expander; this would also allow operating the different pumps and the compressor at different rotational speeds. The optional additional expander ( 85 ) (see  FIG. 6 a   ) in the energy transfer process ( 120 ) can be connected in the same ways. 
     The external energy can be introduced into the system in many ways, not unlike can be done with existing systems today. The external thermal energy can be generated in a burner through any kind of combustion, it can be introduced through a medium with thermal external energy that transfers its thermal energy through heat exchanger ( 53 ) into the work stream process fluid, it can be solar generated thermal energy, it can be heat-radiation, or any other kind of radiation able to introduce energy that does not even need to be thermal energy into the process or system or any other method to introduce thermal energy into heat exchanger ( 53 ). For the function of the complete process of this invention itself, the way how the external thermal energy is introduced from outside is not important. 
     Sample Calculations 
     Comparing the ‘conventional single-medium-processes’ with this invention based on the relevant calculations of the different energy streams involved, in the form of several simple small tables revealing temperatures and energies at various locations in the system, makes the innovative step, the purpose, and the technological benefit of this invention very clear and easy to understand. 
       FIG. 2  shows as an example of the present state of the art the schematic flow of a typical ‘conventional single-medium-processes’. At arrow ( 01 ) the primary energy enters the system. The small table ( 21 ) shows the temperature to which the used medium of the process will be or can be heated. The small table at ( 21 ) shows then the amount of energy that is introduced into the system as available energy for the process in kilo Joule. All the small tables in  FIGS. 2, 9, 10, and 11  do not show the enthalpies of the streams but the relevant energy solely available for the basic process of conversion from thermal energy to kinetic energy relative to the medium (process fluid) used in the process. (Thermal energy or other energy of a medium relative to its absolute temperature at zero Kelvin is not of interest and therefore also not shown in these Figures.) 
     The different energies in  FIGS. 2, 9, 10, and 11  are always shown relative to the mass of the only single medium that circulates in the process of  FIG. 2  or, in  FIGS. 9 to 11 , the work stream process fluid; therefore they can be compared with each other. Also the primary energy that is entering the system in  FIGS. 2, 9, 10, and 11  is seen in relation to the mass of the main medium of the process or to the work stream process fluid, and not to an external combustion that might produce this energy or to whatever method is used to introduce external thermal energy into the system. 
     In  FIGS. 9, 10, 11 , showing the invention, the masses in the streams change when parallel streams flow together. Therefore the mass is shown in each small table as relative to one kilogram of the work stream process fluid and also relative to two kilogram, clearly indicated in the different tables at the streams. The masses in any embodiment can vary, also the relation between the first and the second work streams can be different than in the examples given here. 
     In  FIG. 2  the main medium is heated at the boiler ( 02 ) and the energy for increasing the temperature, i.e. heating, the steam is shown in the table of stream ( 22 ) and, separately from it, the energy which is needed for the phase change from liquid water to steam, i.e. the evaporation, that has no influence on the temperature and that is not involved in heating the medium, usually steam, of the ‘conventional single-medium-process’ is shown in the small table ( 23 ). The energy that can be converted to kinetic energy is solely the thermal energy when it enters the expander ( 04 ). The energy of the phase change ( 23 ) is not relevant before the condensation of the used medium. It passes through the expander ( 04 ) unchanged. The temperature with which the expanded medium, in most cases steam, leaves after expansion the expander ( 04 ) is clearly above the condensation temperature. This is shown at ( 25 ) where still a small part of the thermal energy is in the medium that keeps this medium above its condensation temperature. The energy of the phase change remains therefore completely unchanged and leaves the expander as it enters it. This is shown in  FIG. 2  as the stream in darker shading with the numbers ( 23 ) and ( 26 ). Only at the condenser ( 05 ) the temperature of the ‘conventional single-medium-process’ is in a temperature range that leads to condensation of the medium used. Only here the energy of the phase change is in the temperature range needed for condensation and goes together with the remaining thermal energy of the medium, i.e. steam, which is above the condensation temperature into the condenser ( 05 ) and as stream ( 27 ) out of the system where it warms the environment. 
     The only part of the introduced external energy, referred to as primary energy ( 21 ) that can be changed into kinetic energy in the ‘conventional single-medium-process’ is the part that is shown at ( 24 ). It cannot reach more than 42% of the energy put into the system of the ‘conventional single-medium-process’. This energy is herein in  FIGS. 2, 9, 10, and 11  referred to as ‘primary kinetic energy’ for the simple reason that the efficiency of the mechanism of the expander ( 04 ) to convert the available thermal energy into kinetic energy is not always the same in each possible application and depends on which specific system is chosen. In order to be able to see clearly the potential of the two processes, the ‘conventional single-medium-process’ and the present invention, it is shown as the ‘primary kinetic energy’ which is the maximum energy that can be extracted from the primary energy that is introduced into the system at the beginning. In  FIG. 2  it is clear that the ‘conventional single-medium-process’ can only use 42% of the introduced external energy for the conversion into kinetic energy at a process with 600° C. The rest of the input energy cannot be converted in the ‘conventional single-medium-process’; it is spent—as explained—in other ways. 
       FIG. 9 ,  FIG. 10 , and  FIG. 11  show the complete process and system of the invention as described herein above in the form of a schematic flow diagram. In the first example shown in  FIG. 9 , thermal energy is introduced at heat exchanger  53  at the same temperature of 600° Centigrade as in the ‘conventional single-medium-process’ shown in  FIG. 2 . The external energy ( 1110 ) is used to heat the second work stream ( 140 ) at heat exchanger ( 53 ). This leads to an increase of temperature and energy as shown at ( 111 ). Independently and parallel to it, the first work stream ( 150 ) is heated at heat exchanger ( 43 ) leading to an increase of temperature and energy as shown at ( 118 ). Both parallel work streams ( 140 ) and ( 150 ) meet before the entrance of the expander at ( 112 ) where they mix and enter the expander ( 46 ) with temperature and energy as shown at ( 112 ). Inside the expander ( 46 ) the heated and pressurised work stream process fluid flash evaporates. The flash evaporation consumes the energy that is necessary for the evaporation. This is a specific amount of energy for the evaporation of the medium, which is different for each process fluid, temperature and pressure. In this example in  FIG. 9  the work stream process fluid is water as in  FIG. 2  to allow easy comparison. The energy that remains as thermal energy after the flash evaporation in the work stream process fluid is much lower than at the entrance of the expander ( 112 ). The first work stream ( 150 ) delivers additional thermal energy, recovered from the condensation. This recovered energy can be used for the flash-evaporation for both parts of the work stream process fluid. In case that all the recoverable energy of the condensation is reintroduced into the first part of the work stream, from the point of view of a calculation no energy from the second work stream ( 140 ) has to be subtracted for the evaporation and from the point of view of a calculation nearly all the amount of energy that was introduced through the second work stream ( 140 ) and is shown at ( 111 ) is available for the conversion to primary kinetic energy ( 113 ). The expanded gaseous medium leaves the expander ( 46 ) at a significant lower temperature shown at ( 114 ). The expansion and conversion to primary kinetic energy leads to a decrease of temperature and pressure. 
     At heat exchanger ( 49 ) the condensation is started by extracting thermal energy ( 114 ). In contrast to the ‘conventional single-medium-process’ in which the condensation of the medium is done using an external source of coolant, in the present invention condensation of the work stream process fluid is done with the energy transfer stream process fluid. By transferring the energy of the condensation into the energy transfer process ( 120 ) the energy of the condensation, shown at ( 115 ), can be kept in the complete system. Because this energy is not useful for the process on such a low temperature level, compressor ( 72 ) elevates the temperature, shown at ( 116 ), so it can be used in heat exchanger ( 43 ). The tables ( 115 ) and ( 116 ) show the difference in temperature. In both tables the temperature is also shown in degrees Kelvin. This is relevant because the temperature from the stream before compressor ( 72 ) and afterwards ( 116 ) needs to be increased in the example of  FIG. 9  by a factor of 2.16 to enable the absorbed energy of the condensation to be at a sufficiently high temperature level so that all of it can be transferred into the work stream process fluid. This increase of temperature is significantly less than in a conventional Diesel engine, compared to compression ratio and also to the reached temperature. 
     The compressed energy transfer stream process fluid is at a sufficient high temperature level ( 116 ) after the compression at compressor ( 72 ) to transfer all the energy that was recovered from the condensation in heat exchanger ( 49 ) to the first work stream ( 150 ) through heat exchanger ( 43 ). The energy that is needed for compressor ( 72 ) has to be taken from the primary kinetic energy at ( 113 ). Also the energy needed for the pumps ( 42 ) and ( 51 ) needs to be taken from the primary energy at ( 113 ). It is therefore an advantageous embodiment to connect the compressor and/or one or both pumps with the energy output of expander ( 47 ). This connection can be in form of a mechanical connection, like a common shaft, also other ways of connection are possible, like hydraulic, pneumatic, or electrical, etc. 
     Another advantage of the present invention over the prior art, besides recovering the energy of the phase change, is the lower temperature that allows more energy to be extracted at heat exchanger ( 53 ) from the external energy source. In the ‘conventional single-medium-process’ the process medium, usually water, is condensed at ambient temperature of the medium, e.g. an air or a water body, outside the system. Therefore the temperature of the process fluid in the ‘conventional single-medium-process’ streaming in  FIG. 2  into heat exchanger ( 02 ) cannot be lower than ambient temperature thus limiting the temperature range of heat exchanger ( 02 ). In the case of the present invention shown in  FIG. 9 , the temperature of the internal work process fluid streaming into the heat exchanger ( 53 ) that exchanges external thermal energy can also be much lower. This then allows more energy be transferred from an external energy source to the work process fluid due to the wider temperature range and/or the ability to also extract thermal energy from an external source at a lower temperature. 
     As can be seen in  FIG. 9  the amount of energy that is available to be converted into primary kinetic energy is with 93%—much higher than the 42% that is the limit of the ‘conventional single-medium-process’. 
       FIG. 10  is the same as  FIG. 9 , except that the entrance temperature ( 1120 ) for the external energy is around 200° Centigrade. At this temperature a ‘conventional single-medium-process’ can only convert around 3.6% of the primary energy fed into the system. 
       FIG. 10  shows the temperature of the second work stream ( 140 ) heated to 190° Centigrade at ( 121 ) where it is mixed with the first work stream ( 150 ) heated to 526° Centigrade at ( 128 ). The combined work streams enter the expander ( 46 ) with the combined temperature of 358° Centigrade at ( 122 ). The work stream process fluid leaves the expander ( 46 ) with a temperature of 110° Centigrade ( 124 ). Thus 95% of the primary energy entering the complete process is available to be converted into primary kinetic energy ( 123 ). 
     The additional energy fed by the first stream shown at ( 128 ) is the recovered energy of the condensation ( 125 ) after heat exchanger ( 49 ). The energy for the compressor ( 72 ) and the pumps ( 42 ) and ( 51 ) has to be subtracted from the primary kinetic energy ( 123 ). 
     The temperature difference of the energy transfer stream process fluid before the compressor ( 72 ) shown at ( 125 ) and after it shown at ( 126 ) can be seen as 436° Centigrade or as a 2.17 times increase of absolute temperature. This is much lower than in a conventional Diesel engine in respect of pressure and temperature. 
     A more extreme example is shown in  FIG. 11  in which the temperature of the primary energy entering the system ( 1130 ) is chosen to be minus 10 degrees Centigrade, shown at ( 1130 ). 
     The process fluid of the work stream in this specific case needs to have a boiling point at or below minus 40° Centigrade. In this extreme example of  FIG. 11  the substance monochlorodifluor-methane with a boiling temperature at around minus 41° Centigrade was chosen, this substance is also known as HCFC-22 or R22 and sufficient data is freely available, allowing an easy examination of the presented calculations. The process fluid of the energy transfer stream can be any gas with a low boiling point, in this example carbon-dioxide or methane can be used. 
     At heat exchanger ( 53 ) the external energy is transferred to a much colder second work stream ( 140 ) with a temperature of minus 40° Centigrade. This leads than to a temperature of the second work stream of minus 10° Centigrade, shown at ( 131 ). The first work stream ( 150 ) comes with a temperature of plus 112.3° Centigrade out of heat exchanger ( 43 ), shown at ( 138 ). Both parallel work streams mix and enter the expander ( 46 ) with a temperature of plus 51.2° Centigrade ( 132 ). The work stream process fluid flash evaporates in expander ( 46 ). By evaporating most of the thermal energy is consumed by the phase change from the liquid phase to the gaseous state. The amount of energy that is delivered by the first work stream has at best the temperature and thus the thermal energy that corresponds with the amount of energy needed for the phase change. When the work stream process fluid evaporates and expands inside the expander ( 46 ) it converts a certain amount of thermal energy into primary kinetic energy ( 133 ). With its remaining thermal energy the gaseous work stream process fluid leaves the expander ( 46 ) expanded and colder than it entered at a temperature of minus 36° Centigrade ( 134 ). There the colder and expanded gaseous work stream process fluid condenses and heat exchanger ( 49 ) transfers the energy of the condensation plus the remaining thermal energy to the energy transfer stream process fluid, which in this case is a gas with a sufficiently low boiling point, for example carbon-dioxide or methane. 
     In  FIG. 11  the temperature of this gas is after the decompression ( 137 ) at minus 55° Centigrade). The cold energy transfer stream process fluid is first heated at heat exchanger ( 49 ) to minus 41 Centigrade ( 135 ) and then compressed ( 72 ) to reach a temperature of plus 117.3° Centigrade ( 136 ) that allows the transfer of the recovered energy of the condensation at heat exchanger ( 46 ) into the first parallel partial stream of the ‘work-stream’. In the example of  FIG. 11 , the ratio of absolute temperature before and after compressor ( 72 ) is less than two. On the suction side this compressor ( 72 ) needs to generate sufficiently low pressure to enable the flow of the energy transfer stream process fluid after the decompression right before heat exchanger ( 49 ). This needs to be strong enough to facilitate the temperature drop to minus 55° Centigrade with the decompression, i.e. the Thomson-Joule effect. The energy for the compressor and pumps ( 42 ) and ( 51 ) needs to taken from the primary energy ( 133 ). 
     Such a system needs good thermal insulation in order to keep heat losses small. The amount of energy from the low external temperature thermal energy that is available to be converted to kinetic energy is in this process at 80% very high. Thermal and mechanical losses need to be subtracted. Because the amount of energy per kilogram is at this temperature range rather small, the losses of the compressors, pumps, and the expander are relative to the primary energy higher than they would be at higher temperature ranges. 
     The calculations made in the three examples in  FIGS. 9 to 11  are based on freely available properties of materials. The person skilled in the arts will have no difficulty to recalculate the numbers. Differences between publications for physical properties will lead to certain differences in the results. The range of the numbers will however, remain in the same ranges. These calculations shown in  FIGS. 2, 9, 10, and 11  are based on real situations not theoretical processes or cycles. 
     As can be understood from the description and the calculations the main advantages of keeping the significant amount of energy of the phase change within the system are only made possible:
         firstly by splitting the work process part that receives energy from outside the system to enable parallel partial heating processes using both the external thermal energy and the energy recovered from the condensation; and   secondly by keeping the energy of the phase change in the system the reachable process efficiencies in all temperature ranges are significantly higher than in any other processes known today.       

     Although embodiments of the invention have been described by way of illustration, it will be understood that the invention may be carried out with many variations, modifications, and adaptations, without exceeding the scope of the claims.