Thermal energy storage system comprising a combined heating and cooling machine and a method for using the thermal energy storage system

• US 9,518,787 B2
• Filed: 11/01/2013
• Issued: 12/13/2016
• Est. Priority Date: 11/01/2012
• Status: Expired due to Fees

• Current Assignee: Skanska Sverige AB (Skanska AB)
• Original Assignee: Skanska Sverige AB (Skanska AB)
• Inventors: Pilebro, Hans, Strand, Tobias, Vestin, Rasmus
• Primary Examiner(s): Ali, Mohammad M
• Application Number:
  US14/439,786
• Publication Number:
  US 20150292810A1
• Time in Patent Office: 1,138 Days
• Field of Search: 621/60, 165/10
• US Class Current: 1/1
• CPC Class Codes: F24D 19/1066 for the combination of central heating and domestic hot water
• CPC Class Codes: F24D 2200/11 Geothermal energy
• CPC Class Codes: F24D 2200/123 Compression type heat pumps
• CPC Class Codes: F24D 3/08 in combination with systems for domestic hot-water supply
• CPC Class Codes: F28D 20/0034 using liquid heat storage material
• CPC Class Codes: F28D 20/0039 with stratification of the heat storage material
• CPC Class Codes: F28D 20/0052 using the ground body or aquifers as heat storage medium
• CPC Class Codes: F28D 2020/0069 Distributing arrangements; Fluid deflecting means
• CPC Class Codes: Y02B 10/40 Geothermal heat-pumps
• CPC Class Codes: Y02E 60/14 Thermal energy storage
• CPC Class Codes: Y02P 80/15 On-site combined power, heat or cool generation or distribution, e.g. combined heat and power [CHP] supply

Abstract

The present invention relates to a thermal energy storage system comprising an energy storage (2) having a vertical temperature gradient and an internal combined heating and cooling machine (15). The internal combined heating and cooling machine (15) is adapted for retrieving energy having a first temperature from the energy storage, while simultaneously returning heated energy having a second higher temperature and cooled energy having a third lower temperature. The invention also relates to a method for using the thermal energy storage system.

Claims

1. A thermal energy storage system comprising an energy storage (2) having a vertical temperature gradient and an internal combined heating and cooling machine (15),

said internal combined heating and cooling machine (15) being adapted for retrieving fluid having a first temperature from the energy storage, while simultaneously returning heated fluid having a second higher temperature and cooled fluid having a third lower temperature, wherein said internal combined heating and cooling machine (15) comprises at least two heat pumps, wherein each heat pump comprises at least two compressors, and wherein said internal combined heating and cooling machine (15) is adapted for alternating the connection between said at least two compressors between series connection and parallel connection.

2. The thermal energy storage system according to claim 1, further comprising a pressurized electrical steam boiler arranged within said energy storage system such that surplus electricity in an electrical grid can be transformed into thermal energy as steam which can be directly injected into the thermal energy storage (2).

3. The thermal energy storage system according to claim 1, further comprising at least one immersion heater arranged within said energy storage (2).

4. The thermal energy storage system according to claim 1, further comprising at least one heat-absorbing system (3, 4).

5. The thermal energy storage system according to claim 1, wherein at least one of said heat-absorbing system (3) is a low temperature system.

6. The thermal energy storage system according to claim 1, wherein at least one of said heat-absorbing system (4) is a high temperature system.

7. The thermal energy storage system according to claim 1, further comprising a heat-emitting system (7).

8. The thermal energy storage system according to claim 4, wherein said heat-emitting system (7) comprises a combined heat and power plant.

9. The thermal energy storage system according to claim 4, wherein said heat-emitting system (7) comprises an electrical hot water boiler and/or an electrical steam boiler.

10. A method for using a thermal energy storage system according to claim 1, comprising the steps of:

retrieving fluid from a first level of temperature from the energy storage (2),

returning heated fluid having a second, higher temperature to a corresponding level of said energy storage (2) or to a heat-emitting system (7), and

returning cooled fluid having a third, lower temperature to a corresponding level of said energy storage (2) or to a heat-absorbing system (3, 4).