A supercritical carbon dioxide power generation Brayton cycle system and method that employs an alternate heat recuperation method and apparatus that utilizes switched banks of bead filled tanks to accumulate and recover the thermal energy of the two streams of working fluid in such a way that the variable thermal properties of the supercritical carbon dioxide can be accommodated without significant loss of thermal efficiency.

A thermal energy storage and retrieval device includes at least one working fluid and a plurality of thermodynamic circuits. Each thermodynamic circuit has a first process exchanging heat with a first material in a first temperature range common for all of the thermodynamic circuits. Each thermodynamic circuit also has a second process exchanging heat with a second material in a second temperature range. The second material comprises a heat storage material or a working fluid in another circuit or another device. Each thermodynamic circuit includes a gas pressure changing device and a liquid pressure changing device.

The present disclosure provides pumped thermal energy storage systems that can be used to store electrical energy. A pumped thermal energy storage system of the present disclosure can store energy by operating as a heat pump or refrigerator, whereby network input can be used to transfer heat from the cold side to the hot side. A working fluid of the system is capable of efficient heat exchange with heat storage fluids on a hot side of the system and on a cold side of the system. The system can extract energy by operating as a heat engine transferring heat from the hot side to the cold side, which can result in network output. Systems of the present disclosure can employ solar heating for improved storage efficiency.

The present disclosure provides pumped thermal energy storage systems that can be used to store electrical energy. A pumped thermal energy storage system of the present disclosure can store energy by operating as a heat pump or refrigerator, whereby network input can be used to transfer heat from the cold side to the hot side. A working fluid of the system is capable of efficient heat exchange with heat storage fluids on a hot side of the system and on a cold side of the system. The system can extract energy by operating as a heat engine transferring heat from the hot side to the cold side, which can result in network output. Systems of the present disclosure can employ solar heating for improved storage efficiency.

A method including: (i) operating a pumped-heat energy storage system (“PHES system”) in a charge mode to convert electricity into stored thermal energy in a hot thermal storage medium (“HTS medium”) by transferring heat from a working fluid to a warm HTS medium, resulting in a hot HTS medium, wherein the PHES system is further operable in a generation mode to convert at least a portion of the stored thermal energy into electricity; and (ii) heating the hot HTS medium with an electric heater above a temperature achievable by transferring heat from the working fluid to the warm HTS medium.

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.

Various embodiments include a system for providing heat, cold, and/or electric power comprising: a first and a second compressor; a first and a second expander; and a first heat store and a second heat store. An output of the first compressor is thermally coupled to a first input of the first heat store and to a second input of the second heat store. An output of the second compressor is thermally coupled to a first input of the second heat store and to a second input of the first heat store. An input of the first expander is thermally coupled to a first output of the first heat store and to a second output of the second heat store. An input of the second expander is thermally coupled to a first output of the second heat store and to a second output of the first heat store.

Various embodiments include a system for providing heat, cold, and/or electric power comprising: a first and a second compressor; a first and a second expander; and a first heat store and a second heat store. An output of the first compressor is thermally coupled to a first input of the first heat store and to a second input of the second heat store. An output of the second compressor is thermally coupled to a first input of the second heat store and to a second input of the first heat store. An input of the first expander is thermally coupled to a first output of the first heat store and to a second output of the second heat store. An input of the second expander is thermally coupled to a first output of the second heat store and to a second output of the first heat store.

A system including: (i) a pumped-heat energy storage system (“PHES system”), wherein the PHES system is operable in a charge mode to convert electricity into stored thermal energy in a hot thermal storage (“HTS”) medium; (ii) an electric heater in thermal contact with the hot HTS medium, wherein the electric heater is operable to heat the hot HTS medium above a temperature achievable by transferring heat from a working fluid to a warm HTS medium in a thermodynamic cycle.