# US 12,222,167 B2 · Arrangement and a method for storing thermal energy in the ground > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,222,167 B2 - Document ID: US12222167B2 - Status: Granted - Kind: B2 - Application number: 18/289,149 - Filed: 2022-05-05 - Published: 2024-11-07 - Granted: 2025-02-11 - Earliest claimed: 2021-05-12 - Applicants: Jakob Isaksson; Karl Johan Hogmalm - Inventors: Jakob Isaksson; Karl Johan Hogmalm - Web page: https://patentgrep.com/patent/US12222167B2 ## CPC - F28D 20/0052: {using the ground body or aquifers as heat storage medium} - F24T 10/15: using bent tubes; using tubes assembled with connectors or with return headers - F24T 10/17: using tubes closed at one end, i.e. return-type tubes - F28D 1/0477: {the conduits being bent in a serpentine or zig-zag} - F28D 7/12: the surrounding tube being closed at one end, e.g. return type (F28D7/14 takes precedence) - Y02E 60/14: Thermal energy storage - F28D: HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT (fluid heaters having heat generating means and heat transferring means F24H; furnaces F27; details of heat-exchange apparatus of general) - F24T: GEOTHERMAL COLLECTORS; GEOTHERMAL SYSTEMS - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract An arrangement for storing thermal energy includes a circuit containing a working fluid, where the circuit has a plurality of pipes which pipes are distributed throughout a volume of the ground forming a heat storage. Each pipe is arranged in a channel in the ground for heat exchange between the working fluid and the ground. The arrangement includes an electrical heating element, where the electrical heating element is arranged in a channel in the ground to heat the ground for storing thermal energy in the heat storage. The working fluid is a liquid having a boiling point above 120° C. at atmospheric pressure. ## Claims ### Claim 1 An arrangement for storing thermal energy, the arrangement comprising a circuit containing a working fluid, the circuit having a plurality of pipes which pipes are distributed throughout a volume of the ground forming a heat storage, each pipe being arranged in a channel in the ground for heat exchange between the working fluid and the ground, and an electrical heating element, the electrical heating element being arranged in a channel in the ground to heat the ground for storing thermal energy in the heat storage, wherein the working fluid is a liquid having a boiling point above 120° C. at atmospheric pressure. ### Claim 2 (depends on 1) An arrangement according to claim 1, wherein the circuit comprises a subcircuit having a set of pipes of the plurality of pipes, which pipes are fluidly connected in series and arranged at different distances from the electrical heating element. ### Claim 3 (depends on 2) An arrangement according to claim 2, wherein the arrangement comprises a heat exchanger and the subcircuit is fluidly connected to the heat exchanger for energy supply from the heat storage. ### Claim 4 (depends on 3) An arrangement according to claim 3, wherein the circuit comprises a plurality of said subcircuit, which subcircuits are connected in parallel to the heat exchanger. ### Claim 5 (depends on 1) An arrangement according to claim 1, wherein a set of pipes of the plurality of pipes is arranged along an imaginary circle where each pipe is arranged at substantially the same distance from a centre point, when looking at the ground from above. ### Claim 6 (depends on 5) An arrangement according to claim 5, wherein the electrical heating element is arranged inside the imaginary circle. ### Claim 7 (depends on 5) An arrangement according to claim 5, wherein the arrangement comprises a plurality of said set of pipes, which sets of pipes are arranged along different imaginary circles, the imaginary circles being arranged concentrically having the centre point in common. ### Claim 8 (depends on 1) An arrangement according to claim 1, wherein the arrangement comprises a plurality of said electrical heating element, which electrical heating elements are distributed throughout the volume of the ground forming the heat storage. ### Claim 9 (depends on 1) An arrangement according to claim 1, wherein the working fluid has a working temperature range from a lowest allowable temperatures to a highest allowable temperature for which working temperature range the working fluid is a liquid at atmospheric pressure. ### Claim 10 (depends on 1) An arrangement according to claim 1, wherein the working fluid is a liquid having a boiling point above 150° C. ### Claim 11 (depends on 1) An arrangement according to claim 1, wherein the working fluid is an oil or a compound or element in a liquid state. ### Claim 12 A method for storing thermal energy, comprising the steps of heating a volume of the ground forming a heat storage, by an electrical heating element, the electrical heating element being arranged in a channel in the ground to heat the ground for storing thermal energy in the heat storage, and transferring heat from the heat storage to an energy carrier for energy supply, by a circuit containing a working fluid, the working fluid being a liquid having a boiling point above 120° C. at atmospheric pressure, the circuit having a plurality of pipes which pipes are distributed throughout said volume of the ground, each pipe being arranged in a channel in the ground for heat exchange between the working fluid and the ground. ### Claim 13 (depends on 12) A method according to claim 12, wherein the working fluid has a working temperature range from a lowest allowable temperature to a highest allowable temperature for which working temperature range the working fluid is a liquid at atmospheric pressure. ### Claim 14 (depends on 12) A method according to claim 12, wherein the working fluid is a liquid having a boiling point above 150° C. ### Claim 15 (depends on 13) A method according to claim 13, wherein the working fluid is a liquid having a boiling point above 150° C. the method comprising transferring heat from an external energy source to the working fluid of the circuit, for storing thermal energy in the heat storage, the temperature of the working fluid being increased to above 120° C. by the external energy source.