Abstract: Aspects of the invention disclosed herein generally provide a heat engine system, a turbopump system, and methods for lubricating a turbopump while generating energy. The systems and methods provide proper lubrication and cooling to turbomachinery components by controlling pressures applied to a thrust bearing in the turbopump. The applied pressure on the thrust bearing may be controlled by a turbopump back-pressure regulator valve adjusted to maintain proper pressures within bearing pockets disposed on two opposing surfaces of the thrust bearing. Pocket pressure ratios, such as a turbine-side pocket pressure ratio (P1) and a pump-side pocket pressure ratio (P2), may be monitored and adjusted by a process control system. In order to prevent damage to the thrust bearing, the systems and methods may utilize advanced control theory of sliding mode, the multi-variables of the pocket pressure ratios P1 and P2, and regulating the bearing fluid to maintain a supercritical state.

Abstract: Systems and methods are provided for charging a pumped thermal energy storage (“PTES”) system. A system may include a compressor or pump configured to circulate a working fluid within a fluid circuit, wherein the working fluid enters the pump at a first pressure and exits at a second pressure; a first heat exchanger through which the working fluid circulates in use; a second heat exchanger through which the working fluid circulates in use; a third heat exchanger through which the working fluid circulates in use, a turbine positioned between the first heat exchanger and the second heat exchanger, configured to expand the working fluid to the first pressure; a high temperature reservoir connected to the first heat exchanger; a low temperature reservoir connected to the second heat exchanger, and a waste heat reservoir connected to the third heat exchanger.

Abstract: Provided herein are heat engine systems and methods for transforming energy, such as generating mechanical energy and/or electrical energy from thermal energy. The heat engine systems may have one of several different configurations of a working fluid circuit. One configuration of the heat engine system contains at least four heat exchangers and at least three recuperators sequentially disposed on a high pressure side of the working fluid circuit between a system pump and an expander. Another configuration of the heat engine system contains a low-temperature heat exchanger and a recuperator disposed upstream of a split flowpath and downstream of a recombined flowpath in the high pressure side of the working fluid circuit.

Abstract: Systems and methods are provided for generating electricity via a pumped thermal energy storage (“PTES”) system. A system may include a pump configured to circulate a working fluid within a fluid circuit, wherein the working fluid enters the pump at a first pressure and exits at a second pressure; a first heat exchanger; a second heat exchanger; a turbine positioned between the first heat exchanger and the second heat exchanger, configured to expand a first portion of the working fluid to the first pressure; a heat rejection heat exchanger configured to remove thermal energy from a second portion of the working fluid; a high temperature reservoir connected to the first heat exchanger; and a low temperature reservoir connected to the second heat exchanger.

Abstract: Aspects of the invention disclosed herein generally provide a heat engine system, a turbopump system, and methods for lubricating a turbopump while generating energy. The systems and methods provide proper lubrication and cooling to turbomachinery components by controlling pressures applied to a thrust bearing in the turbopump. The applied pressure on the thrust bearing may be controlled by a turbopump back-pressure regulator valve adjusted to maintain proper pressures within bearing pockets disposed on two opposing surfaces of the thrust bearing. Pocket pressure ratios, such as a turbine-side pocket pressure ratio (P1) and a pump-side pocket pressure ratio (P2), may be monitored and adjusted by a process control system. In order to prevent damage to the thrust bearing, the systems and methods may utilize advanced control theory of sliding mode, the multi-variables of the pocket pressure ratios P1 and P2, and regulating the bearing fluid to maintain a supercritical state.

Abstract: A turbopump system includes a pump portion including a housing having a pressure release passageway disposed therein. The pump portion is disposed between a high pressure side and a low pressure side of a working fluid circuit. A drive turbine is coupled to the pump portion and configured to drive the pump portion to enable the pump portion to circulate a working fluid through the working fluid circuit. A pressure release valve is fluidly coupled to the pressure release passageway and configured to be positioned in an opened position to enable pressure to be released through the pressure release passageway and in a closed position to disable pressure from being released through the pressure release passageway.

Abstract: Systems and methods are provided for controlling the pressure of a working fluid at an inlet of a main pressurization device of a heat engine system. The heat engine system may include a control system and a working fluid circuit including a waste heat exchanger, an expansion device, a recuperator, a main pressurization device, and a heat exchanger assembly. The heat exchanger assembly may include a plurality of gas-cooled heat exchangers configured to transfer thermal energy from the working fluid to a cooling medium, a plurality of fans configured to direct the cooling medium into contact with the gas-cooled heat exchangers, and a plurality of drivers, each driver configured to drive a respective fan. The control system may be communicatively coupled to the heat exchanger assembly and configured to modulate a rotational speed of at least one fan to regulate a pressure of the working fluid at the inlet.

Abstract: A method includes controlling a bearing fluid supply system to provide the bearing fluid to a hydrostatic bearing of the turbopump assembly. The bearing fluid includes a supercritical working fluid. The method also includes receiving data corresponding to a pressure of the bearing fluid measured at or near a bearing fluid drain fluidly coupled to the hydrostatic bearing, determining a thermodynamic state of the bearing fluid at or near the bearing fluid drain based at least in part on the received data, and controlling a backpressure regulation valve to throttle the backpressure regulation valve between an opened position and a closed position to regulate a backpressure in a bearing fluid discharge line to maintain the bearing fluid in a supercritical state in the hydrostatic bearing and/or at or near the bearing fluid drain.

Abstract: Aspects of the disclosure generally provide a heat engine system and a method for regulating a pressure and an amount of a working fluid in a working fluid circuit during a thermodynamic cycle. A mass management system may be employed to regulate the working fluid circulating throughout the working fluid circuit. The mass management systems may have a mass control tank fluidly coupled to the working fluid circuit at one or more strategically-located tie-in points. A heat exchanger coil may be used in conjunction with the mass control tank to regulate the temperature of the fluid within the mass control tank, and thereby determine whether working fluid is either extracted from or injected into the working fluid circuit. Regulating the pressure and amount of working fluid in the working fluid circuit selectively increases or decreases the suction pressure of the pump to increase system efficiency.

Abstract: The present invention generally relates to heat pumps that utilize at least one solar receiver operating with the same working fluids. In one embodiment, the present invention relates to a hybrid solar heat pump comprised of at least one microchannel heat exchanger with integral solar absorber, at least one compression device as the heat pump for concurrent compression to a higher pressure and mass flow regulator of the working fluid, and at least one working fluid accumulator with the entire system operating with the same working fluid.

Abstract: Embodiments of the invention generally provide a heat engine system, a mass management system (MMS), and a method for regulating pressure in the heat engine system while generating electricity. In one embodiment, the MMS contains a tank fluidly coupled to a pump, a turbine, a heat exchanger, an offload terminal, and a working fluid contained in the tank at a storage pressure. The working fluid may be at a system pressure proximal an outlet of the heat exchanger, at a low-side pressure proximal a pump inlet, and at a high-side pressure proximal a pump outlet. The MMS contains a controller communicably coupled to a valve between the tank and the heat exchanger outlet, a valve between the tank and the pump inlet, a valve between the tank and the pump outlet, and a valve between the tank and the offload terminal.

Abstract: A method for converting thermal energy into mechanical energy in a thermodynamic cycle includes placing a thermal energy source in thermal communication with a heat exchanger arranged in a working fluid circuit containing a working fluid (e.g., sc-CO2) and having a high pressure side and a low pressure side. The method also includes regulating an amount of working fluid within the working fluid circuit via a mass management system having a working fluid vessel, pumping the working fluid through the working fluid circuit, and expanding the working fluid to generate mechanical energy. The method further includes directing the working fluid away from the expander through the working fluid circuit, controlling a flow of the working fluid in a supercritical state from the high pressure side to the working fluid vessel, and controlling a flow of the working fluid from the working fluid vessel to the low pressure side.

Abstract: Aspects of the disclosure generally provide a heat engine system with a working fluid circuit and a method for starting a turbopump disposed in the working fluid circuit. The turbopump has a main pump and may be started and ramped-up using a starter pump arranged in parallel with the main pump of the turbopump. Once the turbopump reaches a self-sustaining speed of operation, a series of valves may be manipulated to deactivate the starter pump and direct additional working fluid to a power turbine for generating electrical power.

Abstract: Aspects of the disclosure generally provide a heat engine system and a method for regulating a pressure and an amount of a working fluid in a working fluid circuit during a thermodynamic cycle. A mass management system may be employed to regulate the working fluid circulating throughout the working fluid circuit. The mass management systems may have a mass control tank fluidly coupled to the working fluid circuit at one or more strategically-located tie-in points. A heat exchanger coil may be used in conjunction with the mass control tank to regulate the temperature of the fluid within the mass control tank, and thereby determine whether working fluid is either extracted from or injected into the working fluid circuit. Regulating the pressure and amount of working fluid in the working fluid circuit selectively increases or decreases the suction pressure of the pump to increase system efficiency.

Abstract: A refrigeration cycle is operated in conjunction with various thermodynamic cycle working fluid circuits to cool a target fluid that may be used in a separate system or duty. In one embodiment, the refrigeration cycle includes an ejector that extracts a motive fluid from the working fluid cycles in order to entrain a suction fluid that is also extracted from the working fluid circuits. Expanding the suction fluid reduces the pressure and temperature of the suction fluid for cooling the target fluid in an evaporator, which evaporates the suction fluid before being entrained into the ejector by the motive fluid. A mixed fluid is discharged from the ejector and injected into the working fluid circuits upstream from a condenser that cools the mixed fluid and the working fluid circulating throughout the working fluid circuits.

Abstract: A thermodynamic cycle is disclosed and has a working fluid circuit that converts thermal energy into mechanical energy on hot days. A pump circulates a working fluid to a heat exchanger that heats the working fluid. The heated working fluid is then expanded in a power turbine. The expanded working fluid is then cooled and condensed using one or more compressors interposing at least two intercooling components. The intercooling components cool and condense the working fluid with a cooling medium derived at ambient temperature, where the ambient temperature is above the critical temperature of the working fluid.

Abstract: The present invention generally relates to heat pumps that utilize at least one solar receiver operating with the same working fluids. In one embodiment, the present invention relates to a hybrid solar heat pump comprised of at least one microchannel heat exchanger with integral solar absorber, at least one compression device as the heat pump for concurrent compression to a higher pressure and mass flow regulator of the working fluid, and at least one working fluid accumulator with the entire system operating with the same working fluid.

Abstract: Solar energy conversion systems and methods use solar collectors and working fluid management systems to provide both efficient and safe operation under a wide range of operating conditions. In one embodiment, a solar collector and at least one fluid accumulator preferably with an integral heat exchanger, and at least two mass flow regulator valves enable working fluid flow into and out of the fluid accumulator.

Abstract: Waste heat energy conversion cycles, systems and devices use multiple waste heat exchangers arranged in series in a waste heat stream, and multiple thermodynamic cycles run in parallel with the waste heat exchangers in order to maximize thermal energy extraction from the waste heat stream by a working fluid. The parallel cycles operate in different temperature ranges with a lower temperature work output used to drive a working fluid pump. A working fluid mass management system is integrated into or connected to the cycles.

Abstract: Systems and methods for recovering energy from waste heat are provided. The system includes a waste heat exchanger coupled to a source of waste heat to heat a first flow of a working fluid. The system also includes a first expansion device that receives the first flow from the waste heat exchanger and expands it to rotate a shaft. The system further includes a first recuperator coupled to the first expansion device and to receive the first flow therefrom and to transfer heat from the first flow to a second flow of the working fluid. The system also includes a second expansion device that receives the second flow from the first recuperator, and a second recuperator fluidly coupled to the second expansion device to receive the second flow therefrom and transfer heat from the second flow to a combined flow of the first and second flows.