The invention relates to a system and to a method for compressed-gas energy storage and recovery comprising at least a first and at least a second heat exchanger, a cold liquid storage means and a hot liquid storage means, as well as a separation means. The separation means is positioned after at least a first heat exchanger. The system comprises at least one means for feeding the liquid leaving the separation means to the cold liquid storage means.

A compressed air energy storage power generation device includes a compression/expansion combined machine having a function to produce compressed air utilizing electric power and a function to generate electric power utilizing the compressed air, a pressure storage unit that is fluidly connected to the compression/expansion combined machine and stores the compressed air, inverters that adjust rotation speed of the compression/expansion combined machine, a flow rate adjustment valve that adjusts amount of the compressed air supplied from the pressure storage unit to the compression/expansion combined machine, and a control device that reduces, when receiving a command value that reduces amount of power generated by the compression/expansion combined machine, amount of power generated by the compression/expansion combined machine by making the inverters to reduce rotation speed of the compression/expansion combined machine and decreasing an opening degree of the flow rate adjustment valve.

Systems and methods for variable pressure inventory control of a closed thermodynamic cycle power generation system or energy storage system, such as a reversible Brayton cycle system, with at least a high pressure tank and an intermediate pressure tank are disclosed. Operational parameters of the system such as working fluid pressure, turbine torque, turbine RPM, generator torque, generator RPM, and current, voltage, phase, frequency, and/or quantity of electrical power generated and/or distributed by the generator may be the basis for controlling a quantity of working fluid that circulates through a closed cycle fluid path of the system.

Systems and methods for variable pressure inventory control of a closed thermodynamic cycle power generation system or energy storage system, such as a reversible Brayton cycle system, with at least a high pressure tank and an intermediate pressure tank are disclosed. Operational parameters of the system such as working fluid pressure, turbine torque, turbine RPM, generator torque, generator RPM, and current, voltage, phase, frequency, and/or quantity of electrical power generated and/or distributed by the generator may be the basis for controlling a quantity of working fluid that circulates through a closed cycle fluid path of the system.

A method of temporarily storing thermal energy via a thermal storage subsystem in a compressed air energy storage system comprising an accumulator disposed at least 300 m underground and having an interior configured to contain compressed air at an accumulator pressure that is at least 20 bar and a gas compressor/expander subsystem in communication with the accumulator via an air flow path for conveying compressed air to the accumulator when in a charging mode and from the accumulator when in a discharging mode.

The present disclosure relates to systems and methods wherein a dilute hydrocarbon stream can be oxidized to impart added energy to a power production system. The oxidation can be carried out without substantial combustion of the hydrocarbons. In this manner, dilute hydrocarbon streams that would otherwise be required to undergo costly separation processes can be efficiently utilized for improving the power production system and method. Such systems and methods particularly can utilize dilute hydrocarbon stream including a significant amount of carbon dioxide, such as may be produced in hydrocarbon recovery process, such as enhanced oil recovery or conventional hydrocarbon recovery processes.

The present disclosure relates to systems and methods wherein a dilute hydrocarbon stream can be oxidized to impart added energy to a power production system. The oxidation can be carried out without substantial combustion of the hydrocarbons. In this manner, dilute hydrocarbon streams that would otherwise be required to undergo costly separation processes can be efficiently utilized for improving the power production system and method. Such systems and methods particularly can utilize dilute hydrocarbon stream including a significant amount of carbon dioxide, such as may be produced in hydrocarbon recovery process, such as enhanced oil recovery or conventional hydrocarbon recovery processes.

Provided herein is a power generation system and method for transforming thermal energy, such as waste heat, into mechanical energy and/or electrical energy. The system employs features designed to accelerate start times, reduce size, lower cost, and be more environmentally friendly. Tire system may include multiple compressors on separate pinion shafts with multiple expanders, a temperature valve upstream of compressors with a mass management system downstream, an intercooler between compressors, and a cascade exchanger. In one embodiment, the system is configured to drive a synchronous generator, with the separate pinion shafts rotating at two separate, but constant, speeds.

Systems and methods for transferring and converting heat to a power cycle using a plurality of heat transfer fluids, loops and heat exchange devices to convert heat to useful work and/or power. Power is generated using intermediate heat transfer loops (IHTL) and an intermediate heat transfer fluid (IHTF) to cool the hot exhaust power cycle fluid (PCF) stream that is at or above its critical conditions. The temperature of the IHTF can be increased by 100° C., 150° C., 200° C., 250° C., 300° C., 350° C., 400° C., 450° C., 500° C., 550° C. or more by exchanging heat with the PCF, either directly or indirectly.

An energy storage-combined cooling, heating and power (S-CCHP) system for a building receives energy from a source, for example an intermittent source, and stores the energy in first and second high temperature energy storage (HTES) units. A Brayton cycle using the first HTES unit produces hot and pressurized air that is further heated in the second HTES unit. The heated air drives a turbine to generate electricity for the building. A portion of the compressed air from the Brayton cycle is diverted to a hot water heat exchanger, then to another turbine to produce electricity to the building. The hot water heat exchanger heats water for the building and the other turbine exhaust cools water for building cooling. Heat exchangers are strategically placed to optimize the thermal efficiency of the cycle. In some embodiments the heat transfer fluid is humidified to improve thermal energy transfer properties.