Electricity generating and air conditioning system with water heater

• US 7,170,191 B2
• Filed: 01/24/2005
• Issued: 01/30/2007
• Est. Priority Date: 08/17/2004
• Status: Expired due to Fees

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Choi, Chang Min, Choi, Won Jae, Lim, Hyung Soo, Kang, Seung Tak, Hwang, Yoon Jei
• Primary Examiner(s): Waks; Joseph
• Application Number:
  US11/039,936
• Publication Number:
  US 20060038404A1
• Time in Patent Office: 736 Days
• Field of Search: None
• US Class Current: 290/2
• CPC Class Codes: F25B 13/00 Compression machines, plants or systems, with reversible cycle defrosting cycles F25B47/02
• CPC Class Codes: F25B 2313/0233 in parallel arrangements
• CPC Class Codes: F25B 2327/001 of the internal combustion type
• CPC Class Codes: F25B 2400/06 Several compression cycles arranged in parallel
• CPC Class Codes: F25B 2500/02 Increasing the heating capacity of a reversible cycle during cold outdoor conditions
• CPC Class Codes: F25B 27/00 Machines, plants or systems, using particular sources of energy F25B30/06 takes precedence
• CPC Class Codes: Y02A 30/274 using waste energy, e.g. from internal combustion engine
• CPC Class Codes: Y02E 20/14 Combined heat and power generation [CHP]

Abstract

A cogeneration system includes an engine, a generator connected to an output shaft of the engine to generate electricity, a heat pump type air conditioner, which uses the electricity generated from the generator, and includes a compressor, a directional valve, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger, a fluid-heating heat exchanger to heat a fluid, and a waste heat recovering means to supply waste heat of the engine to the heat pump type air conditioner or to the fluid-heating heat exchanger, so that the system exhibits a high energy efficiency.

Claims

1. A cogeneration system comprising:

an engine which generates heat during operation;

a generator connected to an output shaft of the engine to generate electricity;

a heat pump air conditioner, which comprises a compressor, a directional valve, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger;

a fluid-heating heat exchanger to heat a fluid;

a pre-heater facing the outdoor heat exchanger; and

waste heat recovering means for supplying the heat from the engine to the fluid-heating heat exchanger without supplying the heat to the pre-heater during a cooling operation of the heat pump air conditioner, and for supplying the heat to the pre-heater during a heating operation of the heat pump air conditioner such that the heat is transferred to the outdoor heat exchanger.

2. The system according to claim 1, wherein the heat pump air conditioner uses the electricity generated from the generator.

3. The system according to claim 1, wherein the waste heat recovering means comprises:

a cooling fluid heat exchanger to absorb heat from cooling a second fluid used to cool the engine;

an exhaust gas heat exchanger to absorb heat from exhaust gas discharged from the engine;

heat transfer means to transfer the heat from at least one of the cooling fluid heat exchanger and the exhaust gas heat exchanger to the fluid heating heat exchanger without transferring the heat from the cooling fluid heat exchanger and the exhaust gas heat exchanger to the pre-heater during the cooling operation of the heat pump air conditioner, and to transfer the heat from at least one of the cooling fluid heat exchanger and the exhaust gas heat exchanger to the pre-heater during the heating operation of the heat pump air conditioner.

4. The system according to claim 3, wherein

the pre-heater pre-heats outdoor air blown toward the outdoor heat exchanger during the heating operation of the heat pump air conditioner.

5. The system according to claim 4, wherein the heat transfer means comprises:

a pre-heater circulation conduit to guide a heat medium to be circulated through the cooling fluid heat exchanger, the exhaust gas heat exchanger, and the pre-heater; and

a fluid heating heat exchanger circulation conduit to guide the heat medium to be circulated through the cooling fluid heat exchanger, the exhaust gas heat exchanger, and the fluid heating heat exchanger.

6. The system according to claim 5, wherein the fluid heating heat exchanger circulation conduit is branched from the pre-heater circulation conduit.

7. The system according to claim 5, wherein the heat transfer means further comprises:

a heat medium circulation pump to pump the heat medium, and thus, to circulate the heat medium through the pre-heater circulation conduit or through the fluid heating heat exchanger circulation conduit.

8. The system according to claim 5, wherein the heat transfer means further comprises:

a control valve to alternately open/close the pre-heater circulation conduit and the fluid heating heat exchanger circulation conduit, and thus, to circulate the heat medium through a selected one of the pre-heater circulation conduit and the fluid heating heat exchanger circulation conduit.

9. The system according to claim 8, wherein the heat transfer means further comprises:

a controller to control the control valve to operate, during the cooling operation of the heat pump air conditioner, in a cooling mode in which the fluid heating heat exchanger circulation conduit is opened, and the pre-heater circulation conduit is closed, and to control the control valve to operate, during the heating operation of the heat pump air conditioner, in a heating mode in which the fluid heating heat exchanger circulation conduit is closed, and the pre-heater circulation conduit is opened.

10. The system according to claim 1, wherein at least one of the engine, the generator, the indoor heat exchanger, and the outdoor heat exchanger comprises a plurality of ones.

11. The system according to claim 1, wherein the fluid is a liquid.

12. The system according to claim 11, wherein the liquid is water.

13. The system according to claim 12, wherein the fluid heating heat exchanger is connected to a hot water consumer via a hot water conduit.

14. The system according to claim 1, wherein the waste heat recovering means stops supplying the heat to the fluid-heating heat exchanger during the heating operation of the heat pump air conditioner.

15. A cogeneration system comprising:

an engine;

a generator connected to an output shaft of the engine to generate electricity;

a cooling fluid heat exchanger to absorb heat from cooling a first fluid used to cool the engine;

an exhaust gas heat exchanger to absorb heat from exhaust gas discharged from the engine;

a heat pump air conditioner, which uses the electricity generated from the generator, and comprises a compressor, a directional valve, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger;

a fluid-heating heat exchanger to heat a second fluid;

a pre-heater to pre-heat outdoor air blown toward the outdoor heat exchanger; and

heat transfer means to transfer the heat from at least one of the cooling fluid heat exchanger and the exhaust gas heat exchanger to the fluid heating heat exchanger without transferring the heat from the cooling fluid heat exchanger and the exhaust gas heat exchanger to the pre-heater during a cooling operation of the heat pump air conditioner, and to transfer the heat from at least one of the cooling fluid heat exchanger and the exhaust gas heat exchanger to the pre-heater during a heating operation of the heat pump air conditioner.

16. The system according to claim 15, wherein the heat transfer means comprises:

a pre-heater circulation conduit to guide a heat medium to be circulated through the cooling fluid heat exchanger, the exhaust gas heat exchanger, and the pre-heater; and

a fluid heating heat exchanger circulation conduit to guide the heat medium to be circulated though the cooling fluid heat exchanger, the exhaust gas heat exchanger, and the fluid heating heat exchanger.

17. The system according to claim 16, wherein the fluid heating heat exchanger circulation conduit is branched from the pre-heater circulation conduit.

18. The system according to claim 16, wherein the heat transfer means further comprises:

a heat medium circulation pump to pump the heat medium, and thus, to circulate the heat medium through the pre-heater circulation conduit or through the fluid heating heat exchanger circulation conduit.

19. The system according to claim 16, wherein the heat transfer means further comprises:

a control valve to alternately open/close the pre-heater circulation conduit and the fluid heating heat exchanger circulation conduit, and thus, to circulate the heat medium through a selected one of the pre-heater circulation conduit and the fluid heating heat exchanger circulation conduit.

20. The system according to claim 19, wherein the heat transfer means further comprises:

a controller to control the control valve to operate, during the cooling operation of the heat pump air conditioner, in a cooling mode in which the fluid heating heat exchanger circulation conduit is opened, and the pre-heater circulation conduit is closed, and to control the control valve to operate, during the heating operation of the heat pump air conditioner, in a heating mode in which the fluid heating heat exchanger circulation conduit is closed, and the pre-heater circulation conduit is opened.

21. The system according to claim 15, wherein at least one of the engine, the generator, the indoor heat exchanger, the outdoor heat exchanger, and the pre-heater comprises a plurality of ones.

22. The system according to claim 15, wherein each of the first fluid and the second fluid is a liquid.

23. The system according to claim 22, wherein the liquid is water.

24. The system according to claim 15, wherein the heat transfer means stops supplying the heat to the fluid-heating heat exchanger during the heating operation of the heat pump air conditioner.

25. A cogeneration system comprising:

an engine;

a generator connected to an output shaft of the engine to generate electricity;

a cooling fluid heat exchanger to absorb heat from cooling a first fluid used to cool the engine;

an exhaust gas heat exchanger to absorb heat from exhaust gas discharged from the engine;

a heat pump air conditioner, which uses the electricity generated from the generator, and comprises an outdoor unit including a compressor, a directional valve, an outdoor heat exchanger, and an expansion device, and an indoor unit including an indoor heat exchanger;

a fluid-heating heat exchanger to heat a second fluid;

a pre-heater to pre-heat outdoor air blown toward the outdoor heat exchanger; and

heat transfer means to transfer the heat from at least one of the cooling fluid heat exchanger and the exhaust gas heat exchanger to the fluid heating heat exchanger without transferring the heat from the cooling fluid heat exchanger and the exhaust gas heat exchanger to the pre-heater during a cooling operation of the heat pump air conditioner, and to transfer the heat from at least one of the cooling fluid heat exchanger and the exhaust gas heat exchanger to the pre-heater during a heating operation of the heat pump air conditioner.

26. The system according to claim 25, wherein at least one of the engine, the generator, the indoor heat exchanger, the outdoor heat exchanger, and the pre-heater comprises a plurality of ones.

27. The system according to claim 25, wherein each of the first fluid and the second fluid is a liquid.

28. The system according to claim 27, wherein the liquid is water.

29. The system according to claim 25, wherein the heat transfer means stops supplying the heat to the fluid-heating heat exchanger during the heating operation of the heat pump air conditioner.