A thermodynamic apparatus (10) comprising a compressor module (100), a turbine module (200), and a regenerative heat exchanger (300) centred on a central axis (12). The compressor module (100), turbine module (200) and regenerative heat exchanger (300) are arranged in series along the central axis (12) such that the regenerative heat exchanger (300) is provided between the compressor module (100) and the turbine module (200).

Waste heat management systems are described. The waste heat management systems include a turbine engine having a compressor section, a combustor section, a turbine section, and a nozzle. The compressor section, the combustor section, the turbine section, and the nozzle define a core flow path that expels through the nozzle. The waste heat management systems also include an auxiliary power unit (APU) system and a waste heat recovery system operably connected to the APU system. The APU system is integrated into a working fluid flow path of the waste heat recovery system.

Power generation systems are described. The systems include a shaft, a compressor operably coupled to a first end of the shaft, a turbine operably coupled to a second end of the shaft, a generator operably coupled to the shaft between the compressor and the turbine, and a working fluid arranged in a closed-loop flow path that flows through each of the compressor and the turbine to drive rotation of the shaft. The shaft includes an internal fluid conduit configured to receive a portion of the working fluid at one of the first end and the second end and convey the portion of the working fluid through the generator to the other of the first end and the second end, wherein the portion of the working fluid is rejoined with a primary flow path of the working fluid.

Power generation systems are described. The systems include a shaft, a compressor operably coupled to a first end of the shaft, a turbine operably coupled to a second end of the shaft, a generator operably coupled to the shaft between the compressor and the turbine, and a working fluid arranged in a closed-loop flow path that flows through each of the compressor and the turbine to drive rotation of the shaft. The shaft includes an internal fluid conduit configured to receive a portion of the working fluid at one of the first end and the second end and convey the portion of the working fluid through the generator to the other of the first end and the second end, wherein the portion of the working fluid is rejoined with a primary flow path of the working fluid.

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.

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.

A power generation system comprising a shared hot side thermal store, a shared cold side thermal store, a plurality of power subunits, and an electrical bus is disclosed. Each of the power subunits may connected or isolated from the shared hot side thermal store and/or the shared cold side thermal store.

A power generation system comprising a shared hot side thermal store, a shared cold side thermal store, a plurality of power subunits, and an electrical bus is disclosed. Each of the power subunits may connected or isolated from the shared hot side thermal store and/or the shared cold side thermal store.

An energy storage plant includes a casing for the storage of a working fluid other than atmospheric air, in a gaseous phase and in equilibrium of pressure with the atmosphere; a tank for the storage of said working fluid in a liquid or supercritical phase with a temperature close to the critical temperature; wherein said critical temperature is close to the ambient temperature. The plant is configured to carry out a closed thermodynamic cyclic transformation, first in one direction in a charge configuration and then in the opposite direction in a discharge configuration, between said casing and said tank; wherein in the charge configuration the plant stores heat and pressure and in the discharge configuration generates energy.

An energy storage plant includes a casing for the storage of a working fluid other than atmospheric air, in a gaseous phase and in equilibrium of pressure with the atmosphere; a tank for the storage of said working fluid in a liquid or supercritical phase with a temperature close to the critical temperature; wherein said critical temperature is close to the ambient temperature. The plant is configured to carry out a closed thermodynamic cyclic transformation, first in one direction in a charge configuration and then in the opposite direction in a discharge configuration, between said casing and said tank; wherein in the charge configuration the plant stores heat and pressure and in the discharge configuration generates energy.