Patent ID: 11873740
Assignee: LAWRENCE LIVERMORE NATIONAL SECURITY, LLC
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F  H  Y | IPC F  H

Claim 14:
15. A system for storing and time-shifting at least one of excess electrical power from an electrical power grid, excess electrical power from a power plant itself, or heat from a heat generating source, in a form of pressure and heat, for future use in assisting with a production of electricity, the system comprising:
a reservoir system containing a quantity of a thermal storage medium, the thermal storage medium including at least one of sand, rocks, manufactured granular material including at least one of ceramic pebbles, or a mixture of manufactured granular material, sand, and rocks, and being configured to be heated;
an oxy-combustion furnace for heating the thermal storage medium during a charge operation using O2 and at least one of natural gas, coal, coke, petroleum, petroleum coke, tires, solid waste, or biomass, or electricity supplied from the power grid or the power plant;
a dryer subsystem for receiving a mixture of gaseous CO2 and water vapor from the reservoir system and generating therefrom CO2 during a charging operation;
a compressor for receiving the CO2 and pressurizing the CO2 for transmission to a CO2 storage reservoir;
a discharge subsystem including:
a heat exchanger having a first input configured to receive heated CO2 from the oxy-combustion furnace during a discharge operation of the system and to generate a first quantity of supercritical CO2 (sCO2) at a first temperature and a first pressure, at a first output thereof;
a Brayton-cycle turbine for receiving the first quantity of sCO2 from the first output of the heat exchanger and generating electricity therefrom at a first output thereof for transmission to the power grid, the Brayton-cycle turbine also configured to produce a second quantity of sCO2 having a second temperature and a second pressure at a second output thereof, the second temperature and the second pressure each being lower than the first temperature and the first pressure; and
a recuperator subsystem for circulating the second quantity of sCO2 in a closed loop to reheat and re-pressurize the second quantity of sCO2 to create a third quantity of sCO2 and feeding the third quantity of sCO2 back into the heat exchanger, wherein the heat exchanger further heats the third quantity of sCO2 to produce a re-heated third quantity of sCO2 which is output to the Brayton-cycle turbine to assist in powering the Brayton-cycle turbine.