Sequential pulsing heat-to-power system

Abstract

A sequential pulsing heat-to-power system and method convert low-grade thermal energy into mechanical and electrical power. The system includes heat absorption chambers configured to undergo cyclical heating, discharging, and refilling stages. Each heat absorption chamber includes a heating module containing air, which is pressurized via isochoric heating using a hot coolant sourced from an external heat source. Upon reaching a target temperature and pressure, the pressurized air is discharged through a turbine to generate mechanical work. Ambient air is then drawn in during the refill stage to reset one heat absorption chamber for the next cycle. The system operates sequentially across multiple chambers to enable continuous power generation

Description

SEQUENTIAL PULSING HEAT-TO-POWER SYSTEMCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority to U.S. Provisional Patent Application No. 63 / 639,096, entitled "SEQUENTIAL PULSING HEAT TO POWER SYSTEM’; filed on April 26, 2024, and to U.S. Provisional Patent Application No. 63 / 755,874, entitled “HEAT ABSORPTION CHAMBER”, filed on February 7, 2025, the disclosures of both of which are herein incorporated by reference in their entirety.TECHNICAL FIELD

[0002] The present disclosure relates to a sequential pulsing heat-to-power system for generating useful mechanical work from heat. Specifically, the disclosure is directed towards a sequential pulsing heat-to-power system to generate electric power from low-temperature heat available as waste heat from industrial and other processes.BACKGROUND

[0003] Renewable energy generation today is predominantly driven by wind and solar technologies. While these systems offer clean and sustainable energy, they also suffer from several critical limitations. Chief among these is intermittency -the inability to generate power on demand, as output is contingent on environmental conditions such as sunlight availability or wind speeds within an optimal range. Moreover, these technologies are often constrained by geography and climate, and cannot be deployed universally across all locations. They also require large physical footprints relative to the energy they produce, particularly in the case of solar installations.

[0004] In parallel, traditional thermal systems, such as power plants and engines, produce substantial amounts of waste heat as a byproduct of energy conversion. According to the second law of thermodynamics, a significant portion of input heat energy is unavoidably lost rather than converted into useful work. In the United States, for example, of the approximately 100 quadrillion British thermal units (quads) of energy generated annually, over 60 quads are ultimately emitted as waste heat. This thermal waste is commonly released into the environment in the form of hot gases, steam, heated liquids, or. most often, warm air.

[0005] Although waste heat recovery systems exist, they are frequently complex, capital- intensive, and cost-prohibitive, especially at lower temperatures. Conventional technologies for converting heat into power, such as the Traditional Steam Rankine Cycle, Organic Rankine Cycle(ORC), and Kalina Cycle, are generally inefficient or uneconomical when applied to heat sources below approximately 450°F (232°C).

[0006] Accordingly, there exists a need for an economical, scalable, and geographically flexible method for generating renewable electrical power from heat, particularly from low-to-moderate temperature heat sources, such as industrial waste heat or server farm exhaust.SUMMARY

[0007] The following presents a simplified summary' of various aspects of this disclosure in order to provide a basic understanding of such aspects. This summary is not an extensive overview of the disclosure. It is intended to neither identify key or critical elements of the disclosure, nor delineate any scope of the particular implementations of the disclosure or any scope of the claims. Its sole purpose is to present some concepts of the disclosure in a simplified form as a prelude to the more detailed description that is presented later.

[0008] In some aspects, the techniques described herein relate to a sequential pulsing heat-to- power system, including: a heat source; a coolant distributor module coupled to the heat source via a hot coolant inlet; a recovery heat exchanger; and a plurality7of heat absorption chambers, one or more of the plurality of heat absorption chambers including: a turbine module; a heating module including: thermally insulated walls; a first fluid enclosed within the heating module; a heat exchanger configured to receive a second fluid from the coolant distributor module; at least one sensor configured to monitor temperature and pressure of the first fluid; one or more turbine ports, operable in a closed position wherein the heating module is airtight, and operable in an open position wherein air can enter or exit the heating module; air inlets; and air outlets; a coolant inlet coupled to the heat exchanger; a coolant collector; a coolant release valve; a coolant transfer valve; wherein each of the plurality7of heat absorption chambers is configured to operate in a sequential manner, such that in response to the coolant inlet valve of the heat absorption chamber being open, the coolant inlet valves of remaining heat absorption chambers are closed; wherein the heating module is configured to operate in a repeating three-stage cycle including: a heating stage, during which the one or more turbine ports are closed, the one or more air inlets and air outlets are closed, the first fluid is sealed at ambient temperature and pressure, and thermal energy7is transferred from the second fluid through the heat exchanger to the first fluid, increasing pressure of the first fluid via isochoric heating; a discharge stage, initiated in response to the temperature of the first fluid reaching a predetermined threshold, wherein a turbine port of the heat absorption chamber is opened and the pressurized first fluid is directed to the turbine moduleto perform mechanical work, and the turbine port of the heat absorption chamber is closed in response to the pressure approaching ambient pressure; and a refdl stage, wherein the one or more turbine ports are closed and ambient air is introduced into the sealed heating module via the air inlets and residual air is expelled via the air outlets, returning the temperature and pressure of the first fluid to ambient conditions.

[0009] In some aspects, the techniques described herein relate to a method of converting low- temperature heat into mechanical work, the method including: sealing a heating module of one of a plurality' of heat absorption chambers including a fixed volume of air; directing a heated coolant from a heat source through a heat exchanger, wherein the heating module includes the heat exchanger; heating the fixed volume of air within the sealed heating module via the heat exchanger, thereby increasing pressure of the air through an isochoric heating process until a target temperature and pressure is reached; opening a turbine port to discharge the pressurized air from the heating module into a turbine; closing the turbine port in response to a pressure of the air within the heating module approaching ambient pressure; opening one or more air inlets and one or more air outlets to expel heated air from the heating module and to draw in ambient air during a refill stage; closing the one or more air inlets and the one or more air outlets to reseal the heating module; passing the air expelled from the heating module and from the turbine through a recovery heat exchanger, wherein the recovery heat exchanger recaptures unused usable heat of exhaust air in the coolant before it returns to the heat source; and repeating the sealing, heating, discharging, refilling, and resealing steps sequentially across each of the plurality of heat absorption chambers.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present disclosure is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings.

[0011] FIG. 1 depicts a schematic view of a sequential pulsing heat-to-power (SPHP) system.

[0012] FIG. 2 depicts a flowchart providing a process for converting low-temperature heat into mechanical work.

[0013] FIG. 3 depicts an SPHP system assembly having multiple heat absorption chambers (HACs) and a recovery heat exchanger for reclaiming residual heat during the discharge and refill stage.

[0014] FIG. 4 depicts a multi-stage SPHP assembly, which includes multiple instances of the SPHP system.

[0015] FIG. 5 depicts a three-dimensional isometric view of one implementation of the SPHP assembly including five Heat Absorption Chambers (HACs).

[0016] FIG. 6 depicts a schematic view of the coolant distribution loops which operationalize the Cascade Flow Heating Process (CFHP) and control logic in an SPHP system

[0017] FIG. 7 depicts a cross-sectional view of one implementation of a heating module of a heat absorption chamber.

[0018] FIG. 8A depicts a side view of an implementation of the heating module (HM) of a Heat Absorption Chamber (HAC).

[0019] FIG. 8B depicts an isometric view of an HM.

[0020] FIG. 8C depicts a transparent view of an HM.

[0021] FIG. 8D depicts various elements within an HM.

[0022] FIG. 9 depicts the circulation of air during the heating stage of the heating module.

[0023] FIG. 10 depicts the air circulation during the refill stage for replacing heated air in an HM.

[0024] FIG. 11 depicts an isometric view of the lid mechanism.

[0025] FIG. 12A depicts a schematic view of a method for releasing pressurized air from multiple heat absorption chambers in a time-staggered manner into a shared turbine.

[0026] FIG. 12B illustrates graphically the idealized objective of the process of a time-staggered release of pressurized air from heating modules of multiple heat absorption chambers into a shared turbine.

[0027] FIG. 13A depicts a simplified view of a sequential pulsing heat-to-power system in an alternate implementation.

[0028] FIG. 13B depicts a top view of the system of FIG. 13 A.

[0029] FIG. 14 depicts a simplified schematic visualization of additional components of the SPHP system.DETAILED DESCRIPTION

[0030] Before the present subject matter is described in detail, it is to be understood that this disclosure is not limited to the particular implementations described, as such may vary. It should also be understood that the terminology used herein is for describing particular implementations only, and is not intended to be limiting, since the scope of the present disclosure will be limited only by the appended claims. While this disclosure is susceptible to different implementations in different forms, there is shown in the drawings and will here be described in detail a preferred implementation of the disclosure with the understanding that the present disclosure is to be considered as an exemplification of the principles of the disclosure and is not intended to limitthe broad aspect of the disclosure to the implementation illustrated. All features, elements, components, functions, and steps described with respect to any implementation provided herein are intended to be freely combinable and substitutable with those from any other implementation unless otherwise stated. Therefore, it should be understood that what is illustrated is set forth only for the purposes of example and should not be taken as a limitation on the scope of the present disclosure.

[0031] In the following description and in the figures, like elements are identified with like reference numerals. The use of “e.g.,” “etc.,”, “or” and “the like” indicates non-exclusive alternatives without limitation, unless otherwise noted. The use of “having”, “comprising”, “including” or “includes” means “including, but not limited to,” or “includes, but not limited to,” unless otherwise noted.

[0032] Multiple entities listed with “and / or” should be construed in the same manner, i.e., “one or more” of the entities so conjoined. Other entities may optionally be present other than the entities specifically identified by the “and / or” clause, whether related or unrelated to those entities specifically identified. Thus, as a non-limiting example, a reference to “A and / or B,” when used in conjunction with open-ended language such as “comprising” can refer, in one implementation, to A only (optionally including entities other than B); in another implementation, to B only (optionally including entities other than A); in yet another implementation, to both A and B (optionally including other entities). These entities may refer to elements, actions, structures, steps, operations, values, and the like.

[0033] Various aspects of the above referenced system are described in detail herein by w ay of examples, rather than by w ay of limitation.

[0034] A significant challenge in current thermal systems is the efficient recovery and utilization of heat that is otherwise lost as low-grade waste energy. Conventional approaches to converting thermal energy into power (especially from sources below' 450°F) are often inefficient, complex, and economically impractical.

[0035] A solution to existing system that focuses on the following is needed:

[0036] Dispatchable, meaning it can be turned on or off as needed;

[0037] Non-intermittent, allow ing it to operate as baseload power;

[0038] Geographically agnostic, enabling siting independent of local weather or climate;

[0039] Space-efficient, with a minimal physical footprint; and

[0040] Cost-effective, even at lower temperature thresholds.

[0041] The present system provides a sequential pulsing heat-to-power architecture that enables modular, efficient, and continuous conversion of thermal energy into mechanical work. By combining sealed isochoric air heating, pulsed turbine discharge, and a coordinated coolant flow strategy, the system provides a compact, scalable, and economically viable solution for recovering waste heat and generating dispatchable power.

[0042] FIG. 1 depicts a schematic view of a sequential pulsing heat-to-power (SPHP) system 100. Specifically, FIG. 1 depicts an assembly of the SPHP system 100 which includes multiple heat absorption chambers (including a heat absorption chamber 104) and a coolant distribution network). The SPHP system 100 depicts three chambers. However, additional or fewer chambers than depicted may be used.

[0043] The SPHP system 100 includes a hot coolant inlet 118 and a coolant distributor module 120. The SPHP system 100 further includes a heat absorption chamber-1 (104), which includes a chamber-1 coolant inlet valve 122. a chamber-1 coolant inlet tube 156, a chamber-1 coolant distributor 128, a chamber-1 heating module 134, a chamber-1 turbine port 162, a chamber-1 turbine module 106, a chamber-1 coolant collector 140, a chamber-1 coolant release valve 146, and a chamber-1 coolant transfer valve 129.

[0044] Heat absorption chamber- 1 (104) (also referred to as a first heat absorption chamber) is represented by the components contained within dashed lines in FIG. 1. Heat absorption chamber- 2 and heat absorption chamber-3 may include similar features as chamber- 1.

[0045] Specifically heat absorption chamber-2 (also referred to as a second heat absorption chamber) includes a chamber-2 coolant inlet valve 124, a chamber-2 coolant inlet tube 158. a chamber-2 coolant distributor 130, a chamber-2 heating module 136, a chamber-2 turbine port 164, a chamber-2 turbine module 108, a chamber-2 coolant collector 142, a chamber-2 coolant release valve 148, and a chamber-2 coolant transfer valve 131.

[0046] Additionally, a heat absorption chamber-3 (also referred to as a third heat absorption chamber) includes a chamber-3 coolant inlet valve 126, a chamber-3 coolant inlet tube 160. a chamber-3 coolant distributor 132, a chamber-3 heating module 138, a chamber-3 turbine port 166, a chamber-3 turbine module 110, a chamber-3 coolant collector 144, a chamber-3 coolant release valve 150, and a chamber-3 coolant transfer valve 133. The SPHP system further includes a coolant collector module 152, a heat absorption chamber 3 internal connector outlet 125, and a heat absorption chamber 1 internal connector inlet 127. The internal connector outlet 125 may be a tube that connects the third heat absorption chamber back to the heat absorption chamber- 1 (104) via the chamber 1 internal connector inlet 127, in a similar manner as the heat absorptionchamber- 1 (104) connects to the second heat absorption chamber and the second heat absorption chamber connects to the third heat absorption chamber, downstream of the chamber-1 coolant transfer valve 129 and the chamber-2 coolant transfer valve 131. In an implementation, the internal connector outlet 125 may be similar to a tube from the chamber- 1 coolant transfer valve 129 that connects to the chamber-2 coolant distributor 130, and a tube from the chamber-2 coolant transfer valve 131 that connects to the chamber-3 coolant distributor 132.

[0047] Hot coolant (e.g., water, refrigerant, oil, glycol or the like, but not limited thereto) provided by a heat source 102 is transmitted to the coolant distributor module 120 via the hot coolant inlet 118. The coolant distributor module 120 then distributes this hot coolant (which may be heated to maximum temperature, e.g., a temperature that is equal or close to the temperature of the heat source 102). If, for instance, a data center is acting as the heat source, the maximum temperature of the hot coolant may be between 45-100 degrees Celsius or another temperature and therefore, the maximum temperature may be dependent on the heat source and may be equal to the temperature at the heat source minus heat loses up until the point that it reaches the coolant distributor module 120.

[0048] The chamber- 1 coolant inlet valve 122, the chamber-2 coolant inlet valve 124, and the chamber-3 coolant inlet valve 126 each control the flow of the heated coolant to a respective heat absorption chamber.

[0049] The heat absorption chamber-1 (104) is depicted by dashed lines and all components within these lines are included within the heat absorption chamber- 1 (104) in FIG.l. In an implementation, in any given time, only one of the coolant inlet valves (e.g., the chamber- 1 coolant inlet valve 122, the chamber-2 coolant inlet valve 124, or the chamber-3 coolant inlet valve 126) is open while the other two remain closed. This ensures that the heated coolant from the heat source 102 is directed to only one of the set of heat absorption chambers at a time. Therefore, at first, the coolant is able to enter and pass through the chamber- 1 coolant inlet valve 122, while the chamber-2 coolant inlet valve 124 and the chamber-3 coolant inlet valve 126 are closed. The coolant is then passed through the chamber- 1 coolant inlet tube 156 to the coolant distributor 128, which splits up the coolant into streams and which are then permitted to enter the chamber- 1 heating module 134 from multiple points to allow fast heating of the air inside the chamber. Although three streams entering three tubes are depicted in the drawings, in other implementations, fewer or greater streams may enter fewer or greater tubes than depicted. Furthermore, although the coolant distributor 128 is depicted, in other implementations, the coolant distributor 128 may be replaced by a single inlet into the chamber- 1 heating module 134.In an implementation, a device such as a pump (not depicted) may push the coolant through coolant distributor 128 to enter the chamber-1 heating module 134 and this pump may be placed in coolant distributor module 120 or coolant collector module 152. Once the coolant passes through the chamber-1 heating module 134, it is collected in the chamber-1 coolant collector 140. which collects all the coolant passed through the chamber-! heating module 134 into a single channel.

[0050] After the coolant passes through the chamber-1 heating module 134 to the chamber-1 coolant collector 140, the coolant is to be passed through the rest of the heat absorption chambers. Therefore, the chamber- 1 coolant release valve 146 is closed and the chamber- 1 coolant transfer valve 129 transmits the coolant to the chamber-2 coolant distributor 130. The same process described above in chamber- 1 may be repeated for chamber-2 (utilizing the chamber-2 components which are similar to the chamber- 1 components) enabling the coolant to split into streams and be delivered to the chamber-2 heating module 136. The hot coolant delivers heat to raise the temperature of the air in chamber-2 and then is collected in chamber-2 coolant collector 142. As there is one other heat absorption chamber which has not yet received the coolant, the chamber-2 release valve 148 is closed and the chamber-2 coolant transfer valve 131 transmits the coolant to chamber-3. Subsequently, the coolant enters the chamber-3 coolant distributor 132 and splits into streams and is passed through a heat exchanger inside the chamber-3 heating module 138. Details regarding the heat exchanger are provided herein below' in FIGs. 7, 8A-8D, 9, and 10.

[0051] The coolant is then collected in the chamber-3 coolant collector 144. Since all chambers have now received the coolant, and as chamber-3 is the last in the loop, the chamber-3 coolant release valve 150 is opened thus allowing the coolant to exit into the coolant collector module 152 from where it is returned to the heat source 102 through a coolant outlet 154.

[0052] In an implementation, the coolant is configured to transfer thermal energy' sequentially and the coolant is transmitted through multiple heat absorption chambers in a Cascade Flow Heating Process (CFHP), such that the coolant sequentially transfers thermal energy to each of the multiple heat absorption chambers before being returned to the heat source.

[0053] In an implementation, the coolant is provided to at least two heat absorption chambers. The coolant passes through each of the two heat absorption chambers in sequence before exiting from a second of the two heat absorption chambers. In response to a temperature of the first of the two heat absorption chambers meeting a targeted temperature threshold, the coolant enters the second of the two heat absorption chambers first, and exits from the first of the two heatabsorption chambers. In response each of the two heat absorption chambers reaching a maximum available temperature, the sequence is repeated. The SPHP system network uses valves and pipes in order to pass the coolant according to the above sequence.

[0054] The heat absorption chamber-1 (104) includes a chamber-1 heating module 134 which is sealed with air (also referred to as a first fluid, e.g., ambient air) inside as well as a heat exchanger (not depicted in FIG. 1) inside. Heat is transferred to the air inside the chamber- 1 heating module 134 from the coolant passing through the heat exchanger of heating module 134. When the fixed volume of air inside the chamber- 1 heating module 134 is heated, it undergoes an isochoric heating process, whereby pressure of air rises in response to the rise in temperature due to the introduction of the heated coolant. As a result, once the air is heated to the maximum possible temperature by the coolant, which is a temperature very close to the temperature of the heat source 102, air inside the chamber-1 heating module 134 is also pressurized to the maximum possible pressure from an isochoric heating process. The maximum temperature is determined by the effectiveness of the heating process. In an implementation, the maximum temperature may be 1- 5 degree Celsius less than the temperature of the heat source 102. Once the air inside the heating module 134 of the heat absorption chamber-1 (104) reaches the targeted pressure and temperature (the air pressure and temperature may be checked by one or more sensors), the chamber- 1 turbine port 162 is opened releasing the pressurized air into the chamber- 1 turbine module 106. The targeted temperature may be equal to the temperature of the source (Ts) minus an infinitesimal difference (Te). Thus, the targeted temperature is: Ts - Te, where Te -> 0.

[0055] The turbine module 106 may have multiple implementations including the following. In one implementation, a microturbine (a very small turbine) may be contained or otherwise housed within the turbine module 106. The pressurized and heated air from the chamber- 1 heating module 134 passes through the microturbine of turbine module 106. As this heated and pressurized air passes through the microturbine, it turns the rotor of the microturbine, thereby converting the enthalpy of the heated and pressurized into mechanical work. This mechanical work may then be transferred to an electric generator which converts the mechanical work to electric power. The air exiting the microturbine has its pressure reduced close to outside (ambient) pressure, and its temperature also reduces as enthalpy reduces through the transfer of energy to the microturbine. The air exiting from the microturbine may exit at a pressure higher than ambient, however, the design of the microturbine will be such that the pressure of exiting air is very close to ambient air (less than few thousand Pascals).

[0056] In this first example, each heat absorption chamber has its own microturbine and may also have its own electric generator as well.

[0057] In a second example, all the heat absorption chambers may share a single turbine and electric generator. This is described in more detail in FIGS. 12A. 12B. 13A. and 13B. In this implementation, the turbine modules 106, 108 and 110, deliver the pressurized and heated air from the heating modules (the chamber- 1 heating module 134, the chamber-2 heating module 136 and the chamber-3 heating module 138), to a single turbine through a network of ducts. The pressurized and heated air may be delivered sequentially, such that at one time, only one heating module delivers pressurized and heated air to the shared turbine. However, there may be small durations of overlap, as described herein.

[0058] The duration wherein air inside the heating module of a heat absorption chamber is heated, while the heating module is sealed air-tight, may be called the Heating Stage. The duration wherein the pressurized and heated air inside the heating module of the heat absorption chamber is released into the turbine module may be called the Discharge Stage.

[0059] The heating module 134 of the heat absorption chamber-1 (104) completes the discharge stage, once the pressure of the air inside the heating module 134 becomes equal to the ambient pressure. At this point of time, the air inlets and air outlets of the heating module 134 are opened to allow fresh air to be pulled into the heating module and bring its temperature back close to ambient. This duration wherein fresh (cold) air is drawn into the heating module of the heat absorption chamber may be called the Refill Stage.

[0060] While heating module 134 of heat absorption chamber- 1 (104) is in heating stage, the following configuration of valves is executed: coolant inlet valve 122 is open; coolant inlet valves 124 and 126 are closed; transfer valves 129 and 131 are open, while transfer valve 133 is closed; coolant release valves 146 and 148 are closed, while coolant release valve 150 is open. As a result, the coolant is heated to its maximum available temperature by the heat source 102, fed into heat absorption chamber-1 (104) via coolant inlet valve 122; transferred to heating module 136 of heat absorption chamber-2 via transfer valve 129; then transferred via transfer valve 131 to heating module 138 of heat absorption chamber-3; then returned via coolant release valve 150 to coolant collector module 152, from where it returns to heat source 102.

[0061] Once the chamber- 1 heating module 134 is heated to maximum temperature, and moves into a discharge stage (e.g., by feeding air into the turbine), the chamber-1 coolant inlet valve 122 is closed, and the chamber-2 coolant inlet valve 124 is opened, and thereby, the hot coolant from heat source 102 enters the second heat absorption chamber first. This allows the temperature andpressure of the air inside the chamber-2 heating module 136 to be raised to the highest level available with the heat source 102. While the chamber- 1 heating module 134 is discharging air into the chamber- 1 turbine module 106, the chamber- 1 coolant inlet valve 122 is closed. The chamber-2 coolant inlet valve 124 is opened, while chamber-1 coolant release valve 146 and the chamber-2 release valve 148 are kept closed, and the chamber-3 coolant release valve 150 is kept open. Also, the coolant transfer valve 133 is kept closed. As a result, coolant flows from the coolant distributor module 120 to the chamber-2 heating module 136, to the chamber-3 heating module 138 and back to the coolant collector module 152. Once the chamber-1 heating module 134 completes discharging air into the chamber- 1 turbine module 106, and completes the refill stage by drawing in fresh air, and while temperature of air in the chamber-2 heating module 136 is not yet at its maximum, the coolant transfer valve 133 is opened, the chamber-3 coolant release valve 150 is closed, and chamber-1 coolant release valve 146 is opened. As a result, the coolant flows from the coolant distributor module 120 to the chamber-2 heating module 136, to the chamber-3 heating module 138 to the chamber- 1 heating module 134 and then returns via chamber-1 coolant release valve 146 to the coolant collector module 152 and back to the heat source 102. This process is continued until temperature of air in the chamber-2 heating module 136 reaches its maximum. Once air in the chamber-2 heating module 136 reaches its maximum, the chamber-2 turbine port 164 is opened to release the pressurized and heated air into the chamber-2 turbine module 108. At the same time, the chamber-2 coolant inlet valve 124 is closed, the chamber-3 coolant inlet valve 126 is opened. Therefore, while the chamber-2 heating module 136 is discharging, coolant flows from the coolant distributor module 120 to the chamber-3 heating module 138 to the chamber- 1 heating module 134 to the coolant collector module 152 via chamber- 1 coolant release valve 146 and back to the heat source 102. As a result, hot coolant from heat source 102 enters the chamber-3 heating module 138 first. While heated and pressurized air from the chamber-2 heating module 136 is being discharged to the chamber-2 turbine module 108, this coolant flow is maintained. Once air discharge from the chamber-2 heating module 136 is complete, and also refill stage of chamber-2 heating module is complete, chamber- 1 coolant release valve 146 is closed, the chamber- 1 coolant transfer valve 129 is opened and the chamber- 2 release valve 148 is opened. As a result, while air in the chamber-3 heating module 138 is being heated and has not reached the maximum temperature, coolant flows from the coolant distributor module 120 to the chamber-3 heating module 138 to the chamber- 1 heating module 134 to the chamber-2 heating module 136, and the back to the coolant collector module 152 via the chamber- 2 release valve 148, and from the coolant collector module 152 back to the heat source 102. Again,once air in heating module reaches maximum temperature and pressure, heated and pressurized air from the chamber-3 heating module 138 is discharged into the chamber-3 turbine module 110, by opening the chamber-3 turbine port 166. At the same time, the chamber-3 coolant inlet valve 126 is closed and the chamber-1 coolant inlet valve 122 is opened again. So that heated coolant from the heat source 102 enters the chamber- 1 heating module 134 again. As a result, while the chamber-3 heating module 138 is discharging air, coolant flows from the coolant distributor module 120 to the chamber- 1 heating module 134 to the chamber-2 heating module 136 to the coolant collector module 152 via the chamber-2 release valve 148, and then back to the heat source 102. Once the chamber-3 heating module 138 fully discharges air, and refills with fresh cold air, the chamber-2 release valve 148 is closed, the chamber-2 coolant transfer valve 131 is opened and the chamber-3 coolant release valve 150 is opened. As a result, the coolant now flows from the coolant distributor module 120 to the chamber- 1 heating module 134, to the chamber-2 heating module 136 to the chamber-3 heating module 138 and then back to the coolant collector module 152 via the chamber-3 coolant release valve 150, and then back to the heat source 102 from the coolant collector module 152.

[0062] In summary', the heating module is configured to operate in a repeating three-stage cycle: a heating stage, a discharge stage, and a refill stage.

[0063] During the heating stage, the turbine ports are closed, the air inlet(s) and air outlet(s) are closed, the air is sealed at ambient temperature and pressure, and thermal energy is transferred from the coolant through the heat exchanger to the air, thus increasing the pressure of the air via isochoric heating.

[0064] The discharge stage is initiated in response to the temperature of the air reaching a predetermined threshold. The turbine port of the heat absorption chamber is opened and the pressurized air is directed to the turbine module to perform mechanical work. The turbine port of the heat absorption chamber is closed in response to the pressure approaching ambient.

[0065] During the refill stage the turbine port(s) are closed and ambient air is introduced into the heating module via the air inlets which are opened. Additionally, residual air is expelled via the open air outlet(s) thus returning the temperature and pressure of the air inside the heating module to ambient conditions. Although reference is made to residual air that is expelled, the residual air may also be referred to as heated air.

[0066] Although three turbine modules are depicted, in other implementations, fewer or greater turbine modules may be used. Additionally, the turbine module(s) may be located elsewhere.

[0067] FIG. 2 depicts a flowchart providing a process for converting low-temperature heat into mechanical work.

[0068] At step 210, a heating module of one of a plurality' of heat absorption chambers comprising a fixed volume of air is sealed. The one heating module is thermally insulated from its surroundings to prevent heat or mass transfer through its walls.

[0069] At step 220, a heated coolant from a heat source is directed through a heat exchanger. The heating module comprises the heat exchanger. The heated coolant, such as water, refrigerant, oil, and / or a phase changing substance, carries thermal energy' from the heat source through an inlet tube into the heating module where it flows through the internal heat exchanger before exiting. As the coolant passes through the heat exchanger, it transfers heat to the enclosed air inside the heating module.

[0070] At step 230, the fixed volume of air is heated yvithin the sealed heating module via the heat exchanger, thereby increasing pressure of the air through an isochoric heating process until a target temperature and pressure is reached.

[0071] At step 240 a turbine port is opened to discharge the pressurized air from the heating module into a turbine.

[0072] At step 250, the turbine port is closed in response to a pressure of the air within the heating module approaching ambient pressure.

[0073] At step 260, one or more air inlets and one or more air outlets of the heating module are opened to expel heated air from the heating module and to draw in ambient air during a refill stage.

[0074] As the now-depressurized heat absorption chamber is refilled with ambient air, conditions inside the chamber are restored to near-ambient levels of temperature, pressure, and density, although the exact values may' not equal ambient exactly.

[0075] At step 270, the one or more air inlets and the one or more air outlets are closed to reseal the heating module.

[0076] At step 275, the air expelled from the heating module and from the turbine is passed through a recovery heat exchanger, wherein the recovery heat exchanger recaptures unused usable heat of exhaust air in the coolant before returning to the heat source.

[0077] At step 280, the sealing, heating, discharging, refilling, and resealing steps are repeated sequentially across each of the plurality of heat absorption chambers.

[0078] In an implementation, that at least one heat absorption chamber is in a discharge stage while another heat absorption chamber is in a heating stage.

[0079] In an implementation, when the heat transfer raises the temperature of the air, the temperature increase causes a corresponding rise in air pressure, due to the fact that the chamber is sealed and the air is confined to a constant volume. As a result, the air's density7and volume remain unchanged while pressure increases.

[0080] In an implementation, the opening of the turbine port to discharge the pressurized ambient air produces mechanical work.

[0081] In an implementation, the pressurized air from each heating module is delivered to a shared turbine via a duct network. The heating modules discharge in a time-staggered manner to maintain a substantially steady mass flow and pressure profile at the turbine inlet.

[0082] In an implementation, the directing of the heated coolant comprises: routing the coolant sequentially through the heating modules of multiple heat absorption chambers in a cascade flow heating process, such that each downstream module receives coolant at a low er temperature and returning the coolant to the heat source after exiting a final heating module.

[0083] In an implementation, a fan is actuated, where the fan disposed within each heating module which during a refill stage assists in expelling heated air through the one or more air outlets and drawing ambient air through the air inlets; and during a heating stage, assists in transporting air through the heat exchanger.

[0084] In an implementation, the turbine port of each heating module is opened based on a comparison between a measured pressure within the heating module and a predetermined threshold pressure, the pressure being measured by one or more sensors disposed within the heating module.

[0085] In an implementation, electrical power generated by the turbine is conditioned via a power electronics module that includes a capacitor bank, wherein the capacitor bank smooths timevarying output from the turbine into a substantially steady electrical signal deliverable to a load.

[0086] In an implementation, the heated, pressurized air passes through the turbine, driving its rotation and converting thermal and pressure energy into mechanical work. The turbine may be operatively coupled to a dynamo or generator to produce electrical output.

[0087] FIG. 3 depicts an SPHP system assembly 300 having multiple heat absorption chambers (HACs) and a recovery7heat exchanger for reclaiming residual heat during the discharge and refill stage, according to an implementation. The SPHP system assembly 300 includes multiples heat absorption chambers (301-1, 301-2. and 301-3) arranged in a series (i.e., configured to receive heated coolant from a heat source 302 at each of the HACs 301-1, 301-2, 301-3, one after another).Forthe purposes of brevity, the series ofHACs (301-1, 301-2, and 301-3) are collectively referred to as HACs 301A.

[0088] In an implementation, the SPHP assembly 300 also includes a Recovery Heat Exchanger (Recovery HX) 304 and a circulating coolant loop. In an implementation, the heat source 302 supplies thermal energy to a coolant, which exits the heat source 302 as "‘maximum temperature’7coolant 308 (i.e., the maximum temperature operationally permissible to which the heat source 302 may raise the temperature of the coolant). The maximum temperature coolant 308 may range between the temperature of the cold sink locally available, such as ground water and the temperature of the heat source 302. The maximum temperature coolant 308 is transferred through the series of HACs 301 A, enabling heat transfer to the air present within the HACs 301A, as described previously.

[0089] During the heating stage, each of the heating modules in HACs 301 A may absorb heat from the maximum temperature coolant 308 into the air within the heating modules of HACs 301 A, thereby reducing the temperature of the coolant. The coolant is delivered to the HACs 301 A following the Cascade Flow Heating Process (CFHP) described earlier. As the coolant transfers thermal energy’ to the air within each HAC, the coolant gradually loses heat as the coolant moves to the subsequent HAC (e.g.. from the first HAC 301-1 to the second HAC 301-2 to HAC 301-3). By the time the coolant exits the final HAC in the series of the CFHP process, the coolant has lost a significant amount of thermal energy, and the coolant exits as cold coolant 306. During the refill stage, ambient air 314 enters each HAC in the series of HACs 301 A to replace the heated air. The ambient air 314 is drawn into the HACs 301 A, causing the heated air to be expelled as exhaust warm air 312. Additionally, the air exiting the turbine(s) of the SPHP system also joins this air expelled from the HACs 301 A during refill stage, to become part of the exhaust warm air 312.

[0090] In an implementation, the cold coolant 306 flows into the recovery HX 304, while the exhaust warm air 312 is passed through the recovery HX 304 as well, where in residual heat from the exhaust warm air 312 is transferred to the cold coolant 306 inside the recovery HX 304. In this implementation, the exhaust warm air 312 may be directed to the recovery' HX 304, such as through exhaust ducts (not depicted) of the HACs 301A that may be connected to the recovery' HX 304. The exhaust ducts may allow the exhaust w arm air 312 from each of the HACs 301 A of the series and the turbine(s) to be collected / accumulated at the recovery HX 304. The recovery HX 304 may be implemented as a gas to liquid heat exchanger inside a duct.

[0091] The recovery HX 304 may be configured to reduce the temperature of the exhaust warm air 312 to near ambient temperature air 316 by causing the cold coolant 306 to absorb heat from the exhaust warm air 312 collected at the recovery HX 304. The near ambient temperature air 316 may then be released into the surrounding environment. Resultantly, the cold coolant 306 may then absorb the recovered heat from the exhaust warm air 312, becoming partially reheated coolant 310. The partially reheated coolant 310 is subsequently transferred back to the heat source 302, where the coolant undergoes full heating to reach the condition of maximum temperature coolant 308 before recirculating to the HACs 301 A.

[0092] In an implementation, the coolant loop / circuit depicted in FIG. 3 demonstrates a unified system that integrates the flow through both the HACs 301A and the recovery HX 304, thereby enabling efficient heat recovery and reducing thermal energy waste. The solid lines in the FIG. 3 represents the flow path of the coolant (e.g., the circulating coolant loop), while the dotted lines indicate the flow path of the air. Compared to the configuration shown in FIG. 4. where separate coolant paths may be used, the HAC system assembly 300 in FIG. 3 employs a single coolant loop. A single coolant loop may simplify the system design, improve integration, and maximize energy utilization across all components. As the coolant needs to absorb heat from the exhaust warm air 312 and heat from the heat source 302, the thermal power capacity of the coolant needs to increase. In some implementations, the thermal capacity of the coolant is increased by increasing the flow rate of the coolant in the coolant loop to account for the preheating of the coolant in the recovery' HX 304 before the heat source 302.

[0093] FIG. 4 depicts a multi-stage SPHP assembly 400, which includes multiple instances of the SPHP system. The SPHP system includes a first SPHP 401-1 and a second SPHP 401-2, and an inter-stage heat exchanger (IHX) 402. The IHX 402 may be placed between the first SPHP 401- 1 and the second SPHP 401-2, such that first exhaust air (warm) 403-1 from the first SPHP 401- 1 is passed through IHX 402.

[0094] The IHX 402 may be configured to absorb the heat from the first exhaust air 403-1 into a second coolant of IHX 402, and then transfer this heat to the second SPHP 401-2. In such implementations, the first SPHP 401-1 may be configured to receive a first coolant 410 carrying the heat from the heat source, and absorb the heat into the air inside the heat modules of SPHP 401-1, which receives ambient air 414. The heated air may then be expelled (as the first exhaust air 403-1) to the IHX 402 during the discharge and refill stages of SPHP 401-1. The IHX 402 may transfer the heat from the air to the second coolant associated with the IHX 402. The second coolant may be received from the second SPHP 401-2, after cooling and may be referred to ascold second coolant 412A. The portion of the second coolant after being heated may be referred to as heated second coolant 412B. The IHX 402 may then circulate the heated second coolant 412B to the second SPHP 401-2, where the residual heat is absorbed by the air inside SPHP 401- 2. The (cold) second coolant 412A (which may then be cooled due to the absorption of heat in the second SPHP 401-2) may be retumed / recirculated to the IHX 402. Further, after absorbing the heat from the heated second coolant 412B in the air within the SPHP 401-2, the second SPHP 401-2 may be configured to expel exhaust air 403-2 therefrom. Simultaneously, the IHX 402 may exhaust air 404, which is now cooled after passing through IHX 402, wherein the second coolant absorbed the heat. While two SPHPs 401-1 and 401 -2 are depicted in FIG. 4. it may be appreciated that the multi-stage SPHP assembly 400 may be suitably adapted to have any number of SPHP instances.

[0095] In an example, the second SPHP 401-2 may be deploy ed when the incoming temperature of first exhaust air 403-1 is sufficiently high relative to ambient air temperature (e.g., 20°C temperature difference). The second SPHP 401-2 may be configured to extract additional work from this recaptured heat.

[0096] FIG. 5 depicts a three-dimensional isometric view of one implementation of the SPHP assembly 509. In this implementation, the SPHP assembly 509 includes a coolant distributor module 508 configured to selectively transport heated coolant from the heat source to various heat absorption chambers. The SPHP assembly 509 also includes a coolant collector module 510 that receives the coolant after it has passed through the heat absorption chambers and returns it to the heat source. The SPHP assembly 509 further includes a first heat absorption chamber 512 as well as additional heat absorption chambers such as a heat absorption chamber 513. The SPHP assembly 509 also includes a coolant inlet valve 524 and a coolant transfer valve 516. The coolant transfer valve 516 depicted may be one of several coolant transfer valves used to direct coolant flow. Although one coolant inlet valve 524 is depicted, additional coolant inlet valves may be used.

[0097] FIG. 5 provides additional structural context to the schematic apparatus described in FIG. 1 and schematic operation depicted in FIG. 9 (described herein below).

[0098] FIG. 6 depicts a schematic view of the coolant distribution loops which operationalize the Cascade Flow Heating Process (CFHP) and control logic in an SPHP system 600. The system 600 includes a coolant distributor module 618. which controls the delivery’ of heated coolant from the heat source to individual heat absorption chambers. The system 600 also includes a coolant collector module 620, which collects coolant after it passes through the chambers and returns itto the heat source. The system 600 further includes a set of heat absorption chambers with heating modules including a heat absorption chamber- 1 622, a heat absorption chamber-2 624, a heat absorption chamber-3 626, a heat absorption chamber-4 628, and a heat absorption chamber-5 630 as well as their respective coolant loops-a heat absorption chamber-1 loop 632, a heat absorption chamber-2 loop 634, a heat absorption chamber-3 loop 636. a heat absorption chamber-4 loop 638, and a heat absorption chamber-5 loop 640.

[0099] To represent the system’s closed-loop operation, FIG. 6 includes the following wraparound indicators: a heat absorption chamber-2 coolant loop wraparound 642. a heat absorption chamber-3 coolant loop wraparound 644, a heat absorption chamber-4 coolant loop wraparound 646, and a heat absorption chamber-5 coolant loop wraparound 648. These coolant loop wraparounds indicate that the coolant loops exit from one side and re-enter from the other, thus forming a continuous circuit.

[0100] When the heated coolant exits the heat source, it enters the coolant distributor module 618 at its maximum available temperature. In the depicted configuration, five heat absorption chambers are shown, with the heat absorption chamber- 1 622 being the first and the heat absorption chamber-5 630 being the last in the loop 632. However, fewer or greater number of heat absorption chambers than depicted may be utilized. Initially, the heating modules in all chambers may be sealed and contain ambient air at baseline temperature, pressure, and density.

[0101] The heating process begins by activating the heat absorption chamber- 1 coolant loop 632, directing the heated coolant solely to the heat absorption chamber- 1 622 through the heat absorption chamber-1 loop 632. After passing through the heat absorption chamber-1 622, the coolant sequentially flows through the heat absorption chamber-2 624. the heat absorption chamber-3 626, the heat absorption chamber-4 628, and the heat absorption chamber-5 630. The coolant then reaches the coolant collector module 620 and is returned to the heat source, thus completing the loop. This configuration ensures that chamber- 1 622 receives coolant at the highest temperature, allowing it to heat maximally and develop higher internal pressure than the downstream chambers.

[0102] Once the heat absorption chamber- 1 622 reaches its target temperature and pressure, its coolant loop is deactivated, and the heat absorption chamber-2 coolant loop 634 is activated. Activation of the coolant loop refers to the coolant being routed along the given loop. Deactivation refers to the coolant no longer being routed along the given coolant loop. The heat absorption chamber- 1 622’s turbine port is then opened to release the pressurized air into a turbine for energy conversion. While discharging, the heat absorption chamber-1 622 is isolated from thecoolant flow. After the discharge is complete, the heat absorption chamber- 1 622 is refilled with ambient air, resealed, and reinserted into the loop as the final chamber-receiving coolant last in sequence before it returns to the heat source. In an implementation, once the heat absorption- chamber-2 coolant loop 634 is activated, coolant may exit from heat absorption chamber-1 622. However, for the duration that heat absorption chamber- 1 622 is in discharge and refill stage, the coolant loop 634 may exit via heat absorption chamber-5 630, back to coolant collector module 620. Once heat absorption chamber- 1 622 has completed the discharge and refill stages, it returns to the heating stage and the coolant loop 634 exits from heat absorption chamber- 1 622. as shown in FIG.6.

[0103] At this stage, when heat absorption chamber-2 coolant loop 634 is activated, the heat absorption chamber-2 624 is the first to receive the hottest coolant. As with the heat absorption chamber- 1 622, it heats maximally and develops pressure. Once the heat absorption chamber-2 624 reaches its operational threshold, the heat absorption chamber-3 coolant loop 636 is activated, and the heat absorption chamber-2 coolant loop 634 is deactivated. The heated coolant now enters the heat absorption chamber-3 626 first, followed by the heat absorption chamber-4 628 and the heat absorption chamber-5 630, then the heat absorption chamber- 1 622, and then heat absorption chamber-2 624, before returning to the heat source. As noted above, during the time that the heat absorption chamber-2 624 is in discharge and refill stage, the heat absorption chamber-3 coolant loop 636 may skip heating the absorption chamber-2 624, and return back to coolant collector module 620 from heat absorption chamber-1 622. However, once the heat absorption chamber-2 624 completes the discharge and refill stage, and returns to heating stage, the heat absorption chamber-3 coolant loop 636 exits from heat absorption chamber-2 624. This pattern continues, with each heat absorption chamber rotating through the heating, discharging and refill stages in sequence, one after another.

[0104] This rotational heating sequence ensures that each chamber eventually becomes the first to receive the maximum-temperature coolant, enabling it to reach temperatures near that of the heat source. Importantly, a heat absorption chamber cannot be heated beyond the temperature of the coolant entering it; thus, receiving coolant early in the loop maximizes heating efficiency. In some implementations, coolant flow to a chamber in discharge or refill stage may continue uninterrupted.

[0105] The cyclical control logic produces several advantages. It enables the system to absorb the maximum amount of thermal energy from the heat source, ensuring high energy utilization. It also allows for nearly continuous power generation, as one chamber can always be in thedischarge stage while the others are undergoing heating or refill. Additionally, each chamber is periodically positioned to receive the coolant with highest temperatures, which enhances turbine performance by consistently providing high-temperature and high-pressure air for energyconversion.

[0106] Other implementations may allow multiple chambers to discharge simultaneously for increased power output, depending on the application and desired load characteristics.

[0107] FIG. 7 depicts a cross-sectional view of one implementation of a heating module 700 of a heat absorption chamber. The heating module 700 includes a heat exchanger 702, which includes a coolant distributor tube 706 and a set of axial finned tubes 708. During operation, coolant flows through the heat exchanger 702, transferring thermal energy from the coolant to the air contained within the heating module 700.

[0108] The heat exchanger 702 is configured to provide rapid and efficient heat transfer to the air in the heating module 700. Also depicted are the internal wall 704 of the heating module 700, refill ports 710 for allowing ambient air to re-enter the chamber during the refill stage, and an air outlet 712 for expelling air during the refill stage. A turbine port may be placed along the air outlet 712.

[0109] The heat exchanger 702 may be implemented in a variety of structural forms and using different design approaches. The implementation shown is illustrative and not limiting. The heat exchanger may be fabricated from various materials, but will generally compose a material with high thermal conductivity, such as copper or aluminum.

[0110] FIG. 8A depicts a side view of an implementation of the heating module (HM) 800 of a Heat Absorption Chamber (HAC), according to an implementation. HM 800 represents a different implementation of the heating module compared to the implementation proposed in FIG. 7, incorporating certain features that make it more amenable to manufacturability and commercial operation. FIG. 8B depicts an isometric view of the HM 800. As described above, the HM 800 may be used within a system such as the SPHP system 100 described above.

[0111] The HM 800 includes an outer shell 802. The outer shell 802 may include one or more air inlets, viz., air inlets 804 A, 804B, 804C, and an additional air inlet (not depicted in the figures) positioned opposite to the air inlet 804C. The air inlets are collectively referred to as air inlets 804. The air inlets 804 permit an input of air (e.g., ambient air). While four air inlets are depicted in HM 800, it may be appreciated by those skilled in the art that the HM 800 may be adapted to have any number of air inlets in each wall thereof. Further, the HM 800 may include an air outlet 806, and a turbine port 808 defined to permit air to flow out of the outer shell 802. Further, a HeatExchanger (HX) 822, and a fan 816 (depicted in FIGs. 8C and 8D) may be disposed within the outer shell 802.

[0112] In an implementation, the outer shell 802 may correspond to an outer wall of the HM 800. In some implementations, the outer shell 802 is constructed of aluminum. It may be appreciated the outer shell 802 may be constructed of material which may be suitably adapted based on particular requirements (e g., desired thermal conductivity, weight, malleability, and the like). In some implementations, a thermally insulating layer of material may be disposed around the outer shell 802 to reduce thermal conduction losses from the outer shell 802. In an implementation, the air inlets 804 may be openings / pas sages through which ambient air enters the HM 800. In an implementation, the port may include a lid (such as lid / lid mechanism 1100 shown in FIG. 11) configured to operably open and / or close to allow or prevent the ambient air from entering the HM 800, respectively. In some implementations, the HM 800 may be configured to operate in a heating stage, where the lids of the air inlets 804, the air outlet 806, and the turbine port 808 are closed. When the lids are closed, an airtight seal prevents any air transfer between the HM 800 and the ambient environment / air. The HM 800 may be configured to operate in a refill stage, where the lids of the air inlets 804, and the air outlet 806 are opened, w hile the lids of turbine port 808 are kept closed. When the lids of the air inlets 804 are opened, the ambient air is allowed to enter the HM 800. Further, when the lid of the air outlet 806 is opened, the residual air in the HM 800 may be expelled through the air outlet 806.

[0113] The HM 800 may be configured to operate in a discharge stage. In such configuration, the turbine port 808 may be opened while the air inlets 804 and the air outlet 806 are closed, to cause heated and pressurized air in the HM 800 to exit and be directed into a turbine (not shown). The heating of the enclosed air within HM 800 increases pressure thereof, the pressurized and heated air driving the turbine upon being released from the HM 800, and thereby generating electrical power.

[0114] The HM 800 may be designed to efficiently absorb heat from a heat source and / or to convert waste heat into electrical energy. The heat source may be any device that generates heat, such as a data center or an industrial process like steel plants or glass-making industries or even geothermal w ells.

[0115] The HM 800 may utilize unused heat from the heat source for power generation. The HM 800 may also be used to facilitate dissipation of heat from coolants used in cooling systems. In some implementations, the HM 800 may be configured to receive heat through the coolants in the cooling systems associated with the heat source. The cooling systems may absorb heat fromthe heat source through the coolant. The coolant may be any one or a combination of water, refrigerant, oil, or the like, but not limited thereto. The coolant may then be supplied to the heat exchanger within HM 800, wherein heat is transferred from the coolant to the air inside HM 800, thereby reducing the temperature of the coolant and increasing the temperature of the air inside HM 800.

[0116] As described in FIG. 8C, in an implementation, the HM 800 may be areversible / operably sealable container configured to hold air therein, the container being designed to facilitate transfer of heat from the coolant fluid to the air using the HX 822 (as depicted in FIG. 8C). The HX 822 may facilitate the heat transfer between the coolant and the air. In some implementations, the HX 822 may be connected to pipes or ducts that allow the coolant heated by the heat source to flow into the HX 822. The HX 822 may be configured to enable heat transfer from the coolant flowing through the tubes of the HX 822 to the air. The tubes may be made of a thermally conductive material, such as copper, aluminum, or similar materials, which facilitates transfer / conduction of heat from the coolant to the air. Thereafter, the transferred heat may be distributed within the air through convection facilitated by the fan 816.

[0117] In some implementations, the HX 822 may include a labyrinthine or a corrugated piping / tubing through which the coolant may be circulated to maximize the dissipation of heat from the coolant by maximizing the surface area of the HX 822. In some implementations, the HX 822 may include passages to allow air to flow therethrough. The HX 822 may be one of various standard heat exchanger types, such as a micro-fin heat exchanger.

[0118] In an implementation, the fan 816 may be actuated to circulate air inside the HM 800 during the heating stage, ensuring uniform heating and rapid heat transfer, while also expelling warm / heated air from the HM 800 in the refill stage and pulling in fresh ambient air through the air inlets 804A. The air may be heated close to coolant entry temperature. The temperature approach is the temperature difference between an initial temperature of the coolant (at entry into the HM 800) and a final temperature of the air inside the HM 800 at the conclusion of the heating stage. In some implementations, the fan 816 may be configured to direct airflow through the gaps / interstitial spaces between a series of tubes and fins in the HX 822. The coolant may circulate within the tubes, transferring thermal energy to walls of the tubes and the fins via conduction. The airflow passing through the gaps between the tubes and fins facilitates convective heat transfer, enabling efficient thermal energy absorption by the air and promoting heat transfer from the coolant in the HX 822 to the air being circulated within the HM 800.

[0119] As stated, the HM 800 may be configured to operate in any one of the heating stage, the discharge stage, and the refill stage. In an implementation, during the heating stage, the coolant may enter the HX 822, transferring heat to the air inside the sealed HM 800. All the air inlets 804 and the air outlet 806 and turbine port 808 are closed, and the HM 800 is sealed to an air-tight state. As the air heats up, the temperature and pressure of the air inside the HM 800 may rise through an isochoric heating process. The heating process continues until the air temperature approaches the coolant temperature. The heating process may be facilitated by the circulation of the air by the fan 816. Once the temperature and the pressure inside HM 800 reach a selected threshold, the discharge stage may be initiated. During the discharge stage, pressurized air inside the HM 800 may be released through the turbine port 808, into a turbine, thereby spinning / driving the turbine to generate power. Once the pressurized air is released through the turbine port 808 such that the air pressure inside the HM 800 approximately matches the ambient pressure (which may be 101325 Pa on absolute scale, at sea level), the turbine port 808 may be closed. The pressure may be measured by a sensor, etc. Then, the refill stage may be initiated, where the fan 816 may expel the warm air from the previous heating cycle inside the HM 800 through the air outlet 806 and draw in fresh ambient air through the air inlets 804 defined at each outer wall. The air inlets 804 are opened and air outlet 806 is opened for the refill stage. Once the heated air in the HM 800 is replaced with cool air, the HM 800 may be resealed for the next heating stage by closing air inlets 804 and air outlet 806.

[0120] Pairing the fan 816 with the HX 822 inside the HM 800 may present certain challenges. The challenges may include (a) ensuring all air in the HM 800 passes through the HX 822 and minimal volume of air repeatedly recirculates through the HX 822. (b) ensuring a high flow rate of air through the fan 816 in a closed loop by minimizing the pressure drop experienced by air in closed-loop flow, (c) ensuring no pockets of air are left isolated and unmoved, (d) during refill stage, ensuring there are no pockets of warm air left behind un-expelled, (e) also during refill, ensuring fresh ambient air is pulled in with a high flow rate and warm air from the prior heating stage is expelled rapidly to complete the refill stage as quickly as possible, by minimizing pressure drop and minimizing the path length the air has to follow through the HM 800, and (f) minimizing air passing through the HX 822 and retained within the HM 800 during the refill stage. The use of a duct-within-chamber model in the HM 800 (as described in reference to FIGs. 8C and 8D) addresses the aforementioned technical challenges.

[0121] FIG. 8C depicts a transparent view of the HM 800, revealing components placed inside the outer shell 802, such as the HX 822, the fan 816, and an inner duct 812 connecting the fan816 and the HX 822. The inner duct 812 may have the fan 816 on one end and the HX 822 on the other end, to allow the fan 816 to push air through the HX 822. In some implementations, the geometric profile of the inner duct 812 may be defined by dimensions and shape of the fan 816 and the HX 822. For example, a first end of the inner duct 812 may have a circular profile (corresponding to that of the fan 816), and a second end of the inner duct 812 may have a quadrilateral profile (corresponding to that of the HX 822). The inner duct 812 may be disposed within the outer shell 802 such that a first region (e.g., a hot air collection region 810) is formed downstream of the HX 822 and a second region (e.g.. a cold air region 818) is formed upstream of the fan 816. The fan 816, when actuated, may be configured to draw air from the second region 818, and push the air through the inner duct 812 to the HX 822. The air may pass through the HX 822 to the first region 810, while absorbing heat from the HX 822 during the passage.

[0122] In an implementation, a gap (e.g., a duct-wall gap 814) may also be formed between the inner duct 812 and the outer shell 802, which defines a return path for the air during the heating stage. The gap may extend between (and thereby connect) the first region and the second region. The first and the second regions (viz., the hot air collection region 810 and the cold air region 818) may provide a plenum-like volume configured to enable the fan 816 to push air through the HX 822 via the inner duct 812, and then return to the plenum-like volume behind the fan 816 via the gap 814 between the inner duct 812 and the outer shell 802 during the heating stage.

[0123] In an implementation, the air volume within the 800 may be selected to ensure effective heat absorption. If the air volume is too small, the HM 800 may be unable to absorb all the heat from the coolant, while a volume that is too large may make the chamber larger than required, and consequently lead to higher costs. In an implementation, a geometric profile of the HM 800 is optimized based on the dimensions of the fan 816, the HX 822, and connecting inner duct 812. In an implementation, the gap 814 between the inner duct 812 and the outer shell 802 may manage pressure drop and efficiency. In an implementation, a larger gap may allow for higher flow during heating, but may trap heated air therein during the refill stage. In an implementation, a smaller gap may ensure more thorough expulsion of heated air dunng the refill stage, but increases pressure drop during the heating stage.

[0124] In an implementation, the HM 800 may be configured to pass the air through the HX 822, such that the bulk of the air passes through the HX 822 only once during the heating stage. The flow rate of the air may be determined such that the temperature of the air on absorption of heat from the HX 822 becomes substantially equal to that of the coolant on a single pass through the HX 822. In some cases, multiple passes of already heated air may waste energy, as the aircannot absorb more heat, and hence the HM 800 may be configured to continually switch between the heating stage and the refill stage at predetermined intervals defined by the amount of time taken for the air to be circulated once within the HM 800. The predetermined intervals may be pre-calculated times for which the lids should remain open or closed during the different stages of operation. However, in some implementations, the air may be passed through the HX 822 multiple times for efficient heating, such as in cases where the selected flow rate of the air is insufficient to bring the temperature of the air equal to that of the coolant in a single pass.

[0125] FIG. 8D depicts various sensors 820 within the HM 800. The sensors 820 continuously measure parameters such as pressure, temperature, and flow rate of the air. in real-time. In an implementation, the temperature and the pressure may be monitored within the HM 800 to determine the current state of the HM 800 during heating or cooling, and track pressure levels, for operational control. The sensors 820 inside the HM 800 may measure temperature to reflect the progress of air heating and pressure to determine when the HM 800 has reached sufficient pressurization for the discharge stage. For example, when the temperature of the air reaches a threshold (such as when the temperature of the air becomes nearly equal to the temperature of the coolant in the HX 822), or when pressure of the air due to the heat absorption increases to a value greater than a predetermined threshold during the heating stage, the HM 800 may switch from the heating stage to the discharge stage by opening the turbine port 808 and allowing the air to be depressurized. When the pressure reduces to a value less than the predetermined threshold, the HM 800 may shift to the refill stage. In an implementation, the sensors 820 may be placed to measure conditions within the inner duct 812, the duct-wall gap 814. the second region, and the first region, and accordingly control operational state of the HM 800. For example, the sensors 820 may indicate that the heating stage is complete when the temperature of the air at the inner duct 812, the duct wall gap 814, the second region, and / or the first region is substantially equal, and accordingly switch to the discharge stage.

[0126] An HM 800 depicted herein in FIG. 8D, may include several key design features aimed at improving absorption of heat and utilization thereof (such as for energy recovery). The structure and geometry of the HM 800 may be optimized to achieve nearly uniform and rapid heating of air through the HX 822, with minimal fan 816 power consumption. The inclusion of the inner duct 812 and the placement of the air inlets 804 (804A, 804B, 804C), and the air outlet 806 facilitate expulsion of the heated air inside the HM 800 during the refill stage, and circulation of the air for uniform heating during the heating stage.

[0127] Although the figures may use different reference numerals to describe similar or corresponding elements, it will be understood that, in some implementations, an element depicted in one figure may be substituted for or used in place of a corresponding element in another figure and the elements in different figures may be similar to the elements in other figure(s).

[0128] FIG. 9 depicts the circulation of air during the heating stage of the heating module. During heating, all lids of the air inlets 804 and the air outlet 806 (including the turbine port 808) of FIGs. 8A-8D may be sealed, such that the fan 916 circulates the air inside the heating module (HM) 900 in a closed loop. Since all the lids are closed, the fan 916 may be configured to draw air from the second region 918, and push the air through the inner duct 912. As the fan 916 pushes the air through the inner duct 912, the air may pass through the heat exchanger (HX) 922 on the other end of the inner duct 912, which allows heat to be transferred from the coolant to the air. The air (which may be heated by the HX 922, and hereafter referred to as heated air 902) may- then be collected at the first region (i.e., the hot air collection region 910). Due to the air being drawn from the second region 918 by the fan 916 and being pushed into the first region, a pressure differential may be created between the first region and the second region. The pressure differential may cause the heated air 902 to pass through the duct-wall gap 914 from the first region to the second region, thereby circulating the heated air 902. In some implementations, the flow rate of the fan 916 may be controlled such that the heated air 902 pass through the HX 922 only once during the heating stage. The control of lids and the airflow 902 may be integral to the operation of the HM 900. In some implementations, the HM 900 may use pre-calculated timing to determine how long the lids should remain open or closed during the different stages of operation, based on which the flow rate may be determined. In other cases, live sensor data may be used to determine the operation of the lids. During the heating stage, all lids, including the turbine port 808 (viewable in FIGs. 8A and 8B), are closed to circulate air through the HX 922. Further, during the heating stage, pressure may build up within the HM 900 as the air absorbs heat from HX 922. In the discharge stage, the lid associated with the turbine port 808 may be opened to allow pressurized air to exit to activate the turbine, thereby generating power. The turbine port 808 may then be closed, to allow the HM 900 to continue with the other stages.

[0129] Before the heating module performs the next heating stage cycle, the heated air 902 needs to be replaced with cooler air. FIG. 10 depicts the air circulation during the refill stage for replacing the heated air 1002 in the heating module (HM) 1000. During the refill stage, the heated air 1002 inside the HM 1000 is expelled out (the air expelled out form the HM 1000 being hereafter referred to as exhaust air 1012), and new, fresh, cooler air is drawn in from ambient air1008 through the air inlets 1004 (1004A, 1004B) to replace the exhaust air 1012. To replace the heated air 1002, the lids on the air inlets 1004 and the air outlet 1006 may be opened. The fan 1016 may continue to operate as before, unchanged. Since the lid of the air outlet 1006 is open, the heated air 1002 may be expelled out of the HM 1000 by the fan 1016, instead of being collected at a first region 1010. As exhaust air 1012 is pushed out of the HM 1000, a negative pressure may form behind the fan 1016, which may draw ambient air 1008 into the HM 1000 through the duct- wall gap 1014, from the air inlets 1004. The ambient air 1008 drawn in may pass through the duct-wall gap 1014, and move to the second region 1018, and flow through the fan 1016, an inner duct 1013 up to the first region 1010, all the while pushing the heated air 1002 in front of the drawn-in ambient air 1008 (including the heated air 1002 trapped in the duct- wall gap 1014) out of the HM 1000. The cooler ambient air 1008 may be drawn until all heated air 1002 in the HM 1000 is expelled. In some implementations, the duration of the refill stage (or the duration for which the lids are open) may be set to ensure that all the heated air 1002 inside the HM 1000 is expelled and fully replaced with fresh (cold) ambient air 1008. Therefore, the controlled airflow may ensure that heated air 1002 is fully expelled, and the comparatively cooler ambient air 1008 is effectively draw n in, to allow7the HM 1000 to continue heat absorption in the next heating cycle.

[0130] The air inlets 1004 and the air outlet 1006 require mechanisms that enable them to be operably opened and / or closed for the refill stage and the heating stage, respectively, and a mechanism to open the turbine port 808 during the discharge stage. Particularly, such mechanisms must provide an airtight seal w hen closed, without compromising on the flow7rate of the air into and out of the HM 1000 during the refill stage or discharge stage. In existing art, off-the-shelf valves do not meet specific operational requirements, such as achieving high flow7rates for significant air passage, rapid opening and closing within milliseconds, and providing a complete airtight seal to prevent leakage when closed. Additionally, it is desirable to have a maximally open area during the refill stage to maximize unobstructed airflow. To address these limitations, and for other desirable properties of minimal power consumption for energy efficiency and ensuring the design remains compact and cost-effective, the lid mechanism 1 100 is provided.

[0131] FIG. 11 depicts an isometric view7of the lid mechanism 1100. The lid mechanism 1100 may include one or more louvers 1102, a louver rod 1103 corresponding to each louver 1102. silicone seals 1104, a frame 1106, a stepper motor 1108. a crank rod 1110, and electromagnets 1 112. in

[0132] In some implementations, the frame 1106 may be attached to the air inlets 804, the air outlet 806, and / or the turbine port 808 of the HM 800 depicted in FIGs. 8A-8D, and may serve as the structural support for the louvers 1102 and other components of the lid mechanism 1100. In some implementations, the frame 1106 may be attached to the outer shell 802 (in FIGs. 8A-8D) using any attachment means. Examples of the attachment means may include, but not be limited to, screws, nails, rivets, adhesives, welds, interlocking elements, and the like.

[0133] In an implementation, the louvers 1102 may correspond to blades or panels configured to pivot about the corresponding rod 1103 thereof, running along a length of the frame 1106. The louvers 1102 may be operably pivoted to open and close the corresponding opening such as air inlets 804, to control the air flow into and out of the openings. The louvers 1102 may be designed to be lightweight to reduce the power demand on the stepper motor 1108, while being sufficiently rigid to withstand rapid opening and closing.

[0134] Additionally, the louver rods 1103 of the louvers 1102 may be mechanically connected to the crank rod 1110, enabling synchronized opening and closing of the louvers 1102 through lateral motion of the crank rod 1110, powered by the stepper motor 1108. In an implementation, the stepper motor 1108 may drive the crank rod 1110 that connects with all the louvers 1102, enabling synchronized movement of each of the louvers 1102. In an implementation, the crank rod 1110 may facilitate the movement of the louvers 1102 into specific positions. In the open position, the louvers 1102 may be oriented perpendicularly to the frame 1106 to allow air to flow therethrough, and in the closed position, the louvers 1102 may be abutted against the silicone seal 1104 to form an airtight seal and prevent the flow of air therethrough.

[0135] In an implementation, the electromagnets 1112 may be actuated when the lid mechanism 1 100 is closed, to pull (through magnetic coupling) the louvers 1102 onto the silicone seal 1104 to create a firm and airtight seal. In an implementation, the silicone seal 1104 may be positioned along the edges where the louvers 1102 contact the frame 1106, ensuring an airtight closure. When the stepper motor 1108 turns in one direction, the stepper motor 1108 may pull the crank rod 1110, causing the louvers 1102 to move into a near-vertical position, thereby creating an opening for air to pass. In an implementation, when the stepper motor 1108 rotates in the opposite direction, the stepper motor 1108 may move the crank rod 1110 to shift the louvers 1102 into a horizontal position with respect to the frame 1106, thereby closing the lid mechanism 1100 and preventing air to move into or out through the lid mechanism 1100.

[0136] In an implementation, design parameters of the lid mechanism 1100 for the air inlets 804, and the air outlet 806 may be suitably adapted based on the requirements of the use case. In animplementation, the lid for the air outlet 806 may be larger compared to the lids for the air inlets 804 to manage higher airflows. The number of louvers 1102 in each lid mechanism 1100 may be tailored to a size of the lids. The individual height of each louver may be minimized to reduce sweep area during opening and closing motions, thus minimizing unnecessary air displacement during opening and closing, and reducing the load on the stepper motor 1 108 that drives the louvers 1102. In some implementations, the louvers 1102 may be placed / oriented to open outwards, with respect to the interior air volume of the opening, while in other implementations louvers 1102 may be placed to open inwards.

[0137] While in one implementation the pressurized air from the heat absorption chamber is delivered directly to a turbine, other implementations are also possible. When pressurized air is released from the heat absorption chamber, its pressure drops rapidly and the mass flow through the turbine also drops as the pressure drops. Turbines are usually designed to operate optimally at given pressure and mass flow condition. When conditions vary substantially from the design point, the performance of the turbine can reduce significantly. Additionally, if each heat absorption chamber has its own turbine, it increases the capital cost of the system. In an alternate implementation, the pressure from the heat absorption chamber is released in such a way that the mathematical product of the pressure and volume levels results in a pressure times volume curve over time that is sinusoidal in form. Since pressure drops off rapidly and volume of air released increases as the valve opens, the pressure times volume curve can obtain such a shape that appears as a mathematical half sine-wave. When such half sine-waves from multiple heat absorption chambers are combined with the right phase difference (time gap) between them, it can result in a combined pressure times volume in the mixing region that shows a much flatter pattern than the individual pressure times volume curve for a single heat absorption chamber. A flatter pattern implies a condition where the maximum and minimum values of the property being measured (pressure times volume in this case) deviate from the mean value minimally. As a result, the system can deliver to the turbine a pressure and mass flow that is consistent and shows minimum variation over time. This in turn allows the turbine to operate at or near its design point continuously thereby allowing it to perform at a high level of efficiency.

[0138] FIG. 12A depicts a schematic view of a method for releasing pressurized air from multiple heat absorption chambers in a time-staggered manner into a shared turbine such that the resulting pressure-times-volume curve in the turbine mixing region approximates a stable, flattened profile. A turbine mixing region 1292 is provided upstream of the turbine 1294. Heat absorption chamber-1 (1296), heat absorption chamber-2 (1298), heat absorption chamber-3(1200) and heat absorption chamber-4 (1202) deliver pressurized air to the turbine mixing region 1292. At a given point in time, each heat absorption chamber provides a volume of air which may be different from the volume provided by other heat absorption chambers. In FIG. 12A, heat absorption chamber-1 (1296) provides a volume 1204, heat absorption chamber-2 (1298) provides a volume 1206, heat absorption chamber-3 (1200) provides a volume 1208, and heat absorption chamber-4 (1202) provides a volume 1210. If pressures fromheat absorption chambers are Pl from heat absorption chamber- 1, P2 from heat absorption chamber-2, P3 from heat absorption chamber-3, and P4 from heat absorption chamber-4; while volumes of air provided by each heat absorption chamber are vl from heat absorption chamber- 1 (1296), v2 from heat absorption chamber-2 (1298), v3 from heat absorption chamber-3 (1200), and v4 from heat absorption chamber-4 (1202), then the pressure in mixing region is PM = (PI*vI + P2*v2 + P3*v3 + P4*v4) / (vl+v2+v3+v4). By controlling Pl, P2, P3 and P4. and controlling the volumes released vl, v2, v3 and v4, the value of PM at any given time can be maintained within a narrow bound.

[0139] FIG. 12B illustrates graphically the idealized objective of the process of a time-staggered release of pressurized air from heating modules of multiple heat absorption chambers into a shared turbine. The pressure experienced by the shared turbine has minimal variations. The figure on the left side depicts a pressure-versus-time graph 1212 at the turbine inlet when each heat absorption chamber delivers pressurized air to its own turbine, resulting in distinct and periodic pressure spikes. The figure on the right side depicts a pressure-versus-time graph 1214 for a configuration in which a single shared turbine receives pressurized air from multiple heat absorption chambers. In this configuration, the pressure and volume of air released from each chamber are controlled over time such that the deviation of the pressure-times-volume property is minimized with respect to its average value, resulting in a flatter and more stable pressure profile at the turbine inlet.

[0140] FIG. 13 A depicts a simplified view of the sequential pulsing heat-to-power system in an alternate implementation. Specifically, in this implementation, multiple heat absorption chambers provide pressurized air to a single turbine while mixing varying volumes of air at varying pressures upstream of the turbine in order to deliver a relatively stable pressure and mass flow to the turbine over time.

[0141] A heat absorption chamber 1316 and a heat absorption chamber 1318 have respective turbine ports 1326 and 1328 and are connected to the turbine mixing region 1322 through pipes 1320 and 1321. A turbine 1324 is placed downstream of the turbine mixing region 1322. Pressurized air is released from the heat absorption chambers 1316 and 1318 when the turbine ports 1326 and 1328, respectively, are opened. The pressurized air travels through the pipes 1320and 1321 into the turbine mixing region 1322. The mixing of the varying volumes of air from the two chambers with varying pressures results in a total pressure in the turbine mixing region 1322 that is a volume weighted average of the pressure from each chamber. The total volume of air is the sum of the volume from each heat absorption chamber.

[0142] FIG. 13B depicts a top view of the system of FIG. 13A. and also shows additional heat absorption chambers: a heat absorption chamber 1317 and a heat absorption chamber 1319 not visible in FIG. 13 A.

[0143] The sequential pulsing heat-to-power system may require additional components for operation. FIG. 14 depicts a simplified schematic visualization of additional components of the SPHP system. Heat is delivered by a heat source 1430 to the heat absorption chambers that are coupled to turbine 1434. In order to control the operation of the valves, pumps, turbines, other components of the system, a control logic system 1432 is provided which interfaces with these components through sensors and actuators (e.g., valves). In addition, the power output from the dynamo may be run through a capacitor bank and power electronics 1436 to condition the power for delivery to an external electrical load 1440. While the heat source 1430 and external electrical load 1440 are external to this implementation, the control logic system 1432 and the capacitor bank with power electronics 1436 may be internal to the sequential pulsing heat-to-power system 1438. In an implementation, the capacitor bank may absorb a time-varying power output from a generator coupled to the turbine(s) of the system and provide time-steady power to a load coupled to it. A load may also be referred to as an electrical load which is any electrical device that consumes electric power.

[0144] While the implementations are susceptible to various modifications and alternative forms, specific examples thereof have been show n in the drawings and are herein described in detail. It should be understood, however, that these implementations are not to be limited to the particular form disclosed, but to the contrary, these implementations are to cover all modifications, equivalents, and alternatives falling within the spirit of the disclosure. Furthermore, any features, functions, steps, or elements of the implementations may be recited in or added to the claims, as well as negative limitations that define the inventive scope of the claims by features, functions, steps, or elements that are not within that scope.

Claims

CLAIMSWhat is claimed is:

1. A sequential pulsing heat-to-power system, comprising: a heat source; a coolant distributor module coupled to the heat source via a hot coolant inlet; a recovery heat exchanger; and a plurality of heat absorption chambers, one or more of the plurality of heat absorption chambers comprising: a turbine module; a heating module comprising: thermally insulated walls; a first fluid enclosed within the heating module; a heat exchanger configured to receive a second fluid from the coolant distributor module; at least one sensor configured to monitor temperature and pressure of the first fluid; one or more turbine ports, operable in a closed position wherein the heating module is airtight, and operable in an open position wherein air can enter or exit the heating module; air inlets; and air outlets; a coolant inlet coupled to the heat exchanger; a coolant collector; a coolant release valve; a coolant transfer valve; wherein each of the plurality of heat absorption chambers is configured to operate in a sequential manner, such that in response to the coolant inlet valve of the heat absorption chamber being open, the coolant inlet valves of remaining heat absorption chambers are closed; wherein the heating module is configured to operate in a repeating three- stage cycle comprising:a heating stage, during which the one or more turbine ports are closed, the one or more air inlets and air outlets are closed, the first fluid is sealed at ambient temperature and pressure, and thermal energy is transferred from the second fluid through the heat exchanger to the first fluid, increasing pressure of the first fluid via isochoric heating; a discharge stage, initiated in response to the temperature of the first fluid reaching a predetermined threshold, wherein a turbine port of the heat absorption chamber is opened and the pressurized first fluid is directed to the turbine module to perform mechanical work, and the turbine port of the heat absorption chamber is closed in response to the pressure approaching ambient pressure; and a refill stage, wherein the one or more turbine ports are closed and ambient air is introduced into the heating module via the air inlets and residual air is expelled via the air outlets, returning the temperature and pressure of the first fluid to ambient conditions.

2. The sequential pulsing heat-to-power system of claim 1 , wherein the heating module further comprises a fan and an inner duct connecting the heat exchanger and a fan, the inner duct positioned within the heating module such that a gap is defined between the inner duct and the thermally insulated walls of the heating module.

3. The sequential pulsing heat-to-power system of claim 1, wherein air exiting the heat absorption chamber during the refill and discharge stage is directed through a recovery’ heat exchanger configured to extract residual thermal energy from the exiting air, and wherein the extracted thermal energy is transferred to the second fluid, the second fluid comprising cold coolant exiting a last heat absorption chamber, prior to the second fluid returning to the heat source for reheating to the temperature of the heat source.

4. The sequential pulsing heat-to-power system of claim 1 , wherein the first fluid comprises air and the second fluid comprises a coolant comprising at least one of w ater, a refrigerant, oil, and a phase changing substance.

5. The sequential pulsing heat-to-power system of claim 1 , wherein the second fluid is a coolant that is configured to transfer thermal energy sequentially and the coolant is transmitted through the plurality of heat absorption chambers in a cascade flow heating process, such that the coolant sequentially transfers thermalenergy to each of the plurality of heat absorption chambers before being returned to the heat source.

6. The sequential pulsing heat-to-power system of claim 5, wherein the second fluid is provided to at least two heat absorption chambers of the plurality of heat absorption chambers, and wherein the coolant passes through each of the two heat absorption chambers in sequence before exiting from a second of the two heat absorption chambers, and in response to a temperature of the first of the two heat absorption chambers meeting a targeted temperature threshold, the second fluid enters the second of the two heat absorption chambers first, and exits from the first of the two heat absorption chambers, and in response each of the two heat absorption chambers reaching a maximum available temperature, the sequence is repeated.

7. The sequential pulsing heat-to-power system of claim 1 , wherein the heating module further comprises: a fan configured to circulate the first fluid within the heating module; and one or more sensors configured to monitor temperature and pressure within the heating module and to trigger transition between the heating, discharge, and refill stages; wherein the fan is operable: during the heating stage, to promote uniform heat distribution; and during the refill stage, to expel residual heated air and draw in ambient air.

8. The sequential pulsing heat-to-power system of claim 1 , wherein the heating module further comprises: one or more chamber lids operable between a closed position, in which the heating module is sealed, and an open position, in which air is permitted to enter or exit the heating module; and a fan configured to assist with air circulation during both the heating and refill stages; wherein the one or more chamber lids are opened during the refill stage to expel heated air and draw in ambient air, and closed during the heating stage to maintain airtight conditions and also closed during the discharge stage.

9. The sequential pulsing heat-to-power system of claim 1 , wherein the turbine module houses a microturbine, wherein the microturbine is driven by heated and pressurized air that is discharged through the microturbine during the discharge stage of the heating module coupled to the microturbine.

10. The sequential pulsing heat-to-power system of claim 1 , wherein the turbine module comprises a duct structure configured to deliver pressurized and heated air from the heating module coupled to the duct structure to a shared turbine, and wherein each respective turbine module of each of the plurality of heat absorption chambers transmits the heated and pressurized air from the heating module to the shared turbine during the discharge stage of the heating module coupled to duct structure.

11. The sequential pulsing heat-to-power system of claim 10, wherein the pressurized and heated air from the heating module is delivered in a time- staggered step to minimize variations of pressure experienced by the shared turbine from the pressurized and heated air delivered to the shared turbine.

12. The sequential pulsing heat-to-power system of claim 1, further comprising: a control logic system to control actuation of actuators; and a capacitor bank configured to absorb time-varying power output from a generator coupled to one or more turbines and provide time-steady power to an electrical load coupled to it.

13. A method of converting low-temperature heat into mechanical work, the method comprising: sealing a heating module of one of a plurality of heat absorption chambers comprising a fixed volume of air; directing a heated coolant from a heat source through a heat exchanger, wherein the heating module comprises the heat exchanger; heating the fixed volume of air within the sealed heating module via the heat exchanger, thereby increasing pressure of the air through an isochoric heating process until a target temperature and pressure is reached; opening a turbine port to discharge the pressurized air from the heating module into a turbine;closing the turbine port in response to a pressure of the air within the heating module approaching ambient pressure; opening one or more air inlets and one or more air outlets to expel heated air from the heating module and to draw in ambient air during a refill stage; closing the one or more air inlets and the one or more air outlets to reseal the heating module; passing the air expelled from the heating module and from the turbine through a recovery heat exchanger, wherein the recover}- heat exchanger recaptures unused usable heat of exhaust air in the coolant before it returns to the heat source; and repeating the sealing, heating, discharging, refilling, and resealing steps sequentially across each of the plurality of heat absorption chambers.

14. The method of claim 13, wherein the opening of the turbine port to discharge the pressurized air produces mechanical work.

15. The method of claim 13, further comprising delivering the pressurized air from each heating module to a shared turbine via a duct network, wherein the heating modules discharge in a time-staggered manner to maintain a substantially steady mass flow and pressure profile at the turbine inlet.

16. The method of claim 13, wherein directing the heated coolant comprises: routing the coolant sequentially through the heating modules of multiple heat absorption chambers in a cascade flow heating process, such that each downstream module receives coolant at a lower temperature; and returning the coolant to the heat source after exiting a final heating module.

17. The method of claim 13, further comprising actuating a fan disposed within each heating module which during a refill stage assists in expelling heated air through the one or more air outlets and drawing ambient air through the air inlets; and during a heating stage, assists in transporting air through the heat exchanger.

18. The method of claim 13, wherein the turbine port of each heating module is opened based on a comparison between a measured pressure within the heating module and a predetermined threshold pressure, the pressure being measured by one or more sensors disposed within the heating module.

19. The method of claim 13, further comprising conditioning electrical power generated by the turbine via a power electronics module that includes a capacitor bank, wherein the capacitor bank smooths time-vary ing output from the turbine into a substantially steady electrical signal deliverable to a load.

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