Abstract: A pumped thermal energy storage system includes an auxiliary cooling system, a working fluid circuit, a sensor system, and a flow control process. The working fluid circuit further includes a recuperator and a thermal reservoir. The recuperator has a low-pressure side and a high-pressure side and is connected in parallel with the auxiliary cooling system on the low-pressure side. The sensor system senses operational parameters of the working fluid at predetermined points in the working fluid circuit, the sensed operational parameters include temperature and pressure. The flow control process controls the flow of a working fluid through the working fluid circuit responsive to the sensed operational parameters to balance the heat transferred into the working fluid with the heat transferred out of the working fluid.

Abstract: A technique increases the round-trip efficiency (“RTE”) of a pumped thermal energy storage system by changing the coefficient of performance (“COP”) and efficiency of the cycles by changing the temperature ratios of each, which is accomplished by using two separate low temperature reservoirs (“LTRs”) that are at different temperatures. More particularly, the disclosed technique accomplishes this by using a low-temperature thermal reservoir during the charging process that is at a higher temperature than the generating cycle's low-temperature thermal reservoir. The low-temperature thermal reservoirs are “decoupled” and “independently existing”, in that their temperature and utilization are independent of one another. In general, decoupled and independently existing reservoirs may also be different in their independent reservoir media, reservoir location, and heat exchangers.

Abstract: The disclosure provides a heat pump cycle that allows for an improved matching of the T(Q) slopes of the heat pump cycle. More particularly, in the heat pump cycle, the high temperature heat exchange is separated into two stages. Furthermore, a portion of the working fluid that was cooled in the first stage, is further cooled by expansion before being mixed with a heated working fluid for input to the recuperating heat exchanger.

Abstract: A dual rail heat pump cycle includes a low-temperature heat source; a two stage, high-temperature heat exchange process through which, in operation, heat is exchanged with a thermal medium; and a working fluid circuit. The working fluid circuit includes an expansion process; a compression process; a recuperation process, and a pair of parallel flow paths. The recuperation process is interposed between the expansion process and the compression process and has a high-pressure side defined by the compression process and a low pressure side defined by the expansion process. The pair of parallel flow paths between the recuperation process and the high-temperature heat exchange process on the high-pressure side of the recuperation process.

Abstract: A method for operating a pumped thermal energy storage (“PTES”) system includes circulating a working fluid through a working fluid circuit, the working fluid having a mass flow rate and a specific heat capacity and balancing a product of the mass and the specific heat capacity of the working fluid on a high-pressure side of a recuperator and a low side of the recuperator as the working fluid circulates through the working fluid circuit. The PTES system includes a bypass in the working fluid circuit by which a first portion of the working fluid bypasses the high-pressure side of the recuperator while a second portion of the working fluid circulates through the high-pressure side of the recuperator.

Abstract: The disclosure provides a heat pump cycle that allows for an improved matching of the T(Q) slopes of the heat pump cycle. More particularly, the high temperature heat exchange is separated into two stages. Furthermore, a portion of the working fluid that was cooled in the first stage, is further cooled by expansion before being mixed with a heated working fluid for input to the recuperating heat exchanger.

Abstract: A method for operating a pumped thermal energy storage (“PTES”) system includes circulating a working fluid through a working fluid circuit, the working fluid having a mass flow rate and a specific heat capacity and balancing a product of the mass and the specific heat capacity of the working fluid on a high-pressure side of a recuperator and a low side of the recuperator as the working fluid circulates through the working fluid circuit. The PTES system includes a bypass in the working fluid circuit by which a first portion of the working fluid bypasses the high-pressure side of the recuperator while a second portion of the working fluid circulates through the high-pressure side of the recuperator.

Abstract: The disclosure provides a heat pump cycle that allows for an improved matching of the T(Q) slopes of the heat pump cycle. More particularly, the high temperature heat exchange is separated into two stages. Furthermore, a portion of the working fluid that was cooled in the first stage, is further cooled by expansion before being mixed with a heated working fluid for input to the recuperating heat exchanger.

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: 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: 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: 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: Embodiments provide a power generation device that utilizes a working fluid containing carbon dioxide within a working fluid circuit having high and low pressure sides. Components of the device may include a heat exchanger configured to be in thermal communication with a heat source whereby thermal energy is transferred from the heat source to the working fluid, an expander located between the high and low pressure sides of the working fluid circuit and operative to convert a pressure drop in the working fluid to mechanical energy, a recuperator operative to transfer thermal energy between the high and low pressure sides, a cooler operative to control temperature of the working fluid in the low pressure side, a pump operative to circulate the working fluid through the working fluid circuit, and a mass management system configured to control an amount of working fluid mass in the working fluid circuit.

Abstract: Embodiments provide a heat engine system containing working fluid (e.g., sc-CO2) within high and low pressure sides of a working fluid circuit and a heat exchanger configured to transfer thermal energy from a heat source to the working fluid. The heat engine system further contains an expander for converting a pressure drop in the working fluid to mechanical energy, a shaft coupled to the expander and configured to drive a device (e.g., generator or pump) with the mechanical energy, a recuperator for transferring thermal energy between the high and low pressure sides, and a cooler for removing thermal energy from the working fluid in the low pressure side. The heat engine system also contains a pump for circulating the working fluid, a mass management system (MMS) fluidly connected to the working fluid circuit, and a supply tank fluidly connected to the MMS by a supply line.

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: Various thermodynamic power-generating cycles employ a mass management system to regulate the pressure and amount of working fluid circulating throughout the working fluid circuits. 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 helps selectively increase or decrease the suction pressure of the pump, which can increase system efficiency.

Abstract: Embodiments provide a heat engine system containing working fluid (e.g., sc-CO2) within high and low pressure sides of a working fluid circuit and a heat exchanger configured to transfer thermal energy from a heat source to the working fluid. The heat engine system further contains an expander for converting a pressure drop in the working fluid to mechanical energy, a shaft coupled to the expander and configured to drive a device (e.g., generator or pump) with the mechanical energy, a recuperator for transferring thermal energy between the high and low pressure sides, and a cooler for removing thermal energy from the working fluid in the low pressure side. The heat engine system also contains a pump for circulating the working fluid, a mass management system (MMS) fluidly connected to the working fluid circuit, and a supply tank fluidly connected to the MMS by a supply line.

Abstract: A waste heat recovery system and a method for operating a thermodynamic cycle using a working fluid in a working fluid circuit which has a high pressure side and a low pressure side. The system comprises a waste heat exchanger, a waste heat source, an expander, a recuperator, a cooler, a pump, and a mass management system connected to the working fluid circuit. The mass management system comprises a working fluid vessel connected to the low pressure side of the working fluid circuit and configured to passively control an amount of working fluid mass in the working fluid circuit.

Abstract: A waste heat recovery system, method and device executes a thermodynamic cycle using a working fluid in a working fluid circuit which has a high pressure side and a low pressure side.

Abstract: A waste heat recovery system, method and device executes a thermodynamic cycle using a working fluid in a working fluid circuit which has a high pressure side and a low pressure side.