JP2002089928A - Air-conditioning system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air-conditioning system which is contrived to have high energy utilization efficiency and high economic efficiency by utilizing the heat discharged from a cogeneration device while the device supplies electric power to a small-scaled facility. SOLUTION: This air-conditioning system is provided with an air conditioner 2 provided in a room 1 to be air-conditioned, the cogeneration device 3 which is constituted in such a way that the device 3 generates and supplies electric power and the heat generated and discharged from the device 3 when the device 3 generates electric power is taken out by means of a heating medium, and an indoor unit 10 having a heat exchanger 10a which generates an ascending air current in the room 1 by using the heat discharged from the device 3 and taken out by means of the heating medium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioning system that utilizes heat generated in a cogeneration system.

[0002]

In recent years, from the standpoint of global environmental protection, which can be energy saving, CO ₂ reduction and the like, for example, a gas engine generator and gas turbine power generation unit, phosphate type or molten carbonate, solid oxide fuel cell The development of a distributed power generation device such as this is being carried out. For a specific area or large-scale building, a cogeneration system using a gas engine generator or a fuel cell is used to supply hot water and heat using generated heat together with power supply. I have.

[0003] Also, introduction of a cogeneration system into small-scale facilities for general households and shops has been studied, and a micro gas turbine power generation device and a polymer membrane suitable for the power generation device are used. A polymer electrolyte fuel cell having a low operating temperature has been developed. In a cogeneration system applied to such a small-scale facility, from an economic point of view, the power of the entire facility is not provided by the power but by a part of the power.

[0004] In addition, a micro gas turbine power generation device or the like used for a small-scale facility requires a long time to start and a narrow range of variable capacity, so that it always operates at a low output. Further, of the energy of the fuel, only about 35% is used for power generation, and the rest is discharged as heat, and the generated heat is used for hot water supply and heating.

[0005] For this reason, the utilization of the generated heat discharged is a key to installing a cogeneration system, and there is a great demand for hot water supply only in limited facilities such as hospitals. As for the use of heat generated in the summer, cooling and the like are performed by installing an absorption refrigerator in a relatively large-scale facility, but the efficiency of the absorption refrigerator is not good.

For this reason, in a small-scale facility for general households and stores, when a cogeneration system is installed, heat is generated by supplying hot water and heating in winter while supplying power. Is available for air conditioning. However, installing an absorption chiller in the summer to use the generated heat to perform air conditioning is not desirable in terms of installation costs, operating efficiency, and other factors. It has to be thrown away, which is not desirable from the viewpoint of energy utilization, and is not desirable from the viewpoint of economy.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to reduce the generated heat discharged while supplying power to a small-scale facility by a cogeneration system. It is an object of the present invention to provide an air conditioning system that is used effectively and has high utilization efficiency of energy and high economic efficiency.

[0008]

SUMMARY OF THE INVENTION An air conditioning system according to the present invention includes an air conditioning apparatus provided in a room for performing air conditioning, power generation and power supply, and heat generated and discharged with power generation. And a heat dissipating device that generates an ascending airflow in the room by heat discharged from the cogeneration device extracted by the heating medium. Further, the speed of the rising airflow by the heat dissipation device, the cooling operation by the air conditioner, characterized by being made to be variable corresponding to each operation mode of the heating operation, further, The heat dissipating device is provided on the floor in the room so as to heat the room, and furthermore, it operates when heating the room. The utilization ratio by the heat dissipation device of the exhaust heat of the cogeneration system according to the time zone is characterized in that as a variable.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

First, a first embodiment will be described with reference to FIGS. FIG. 1 is a block diagram showing the outline of the system.
FIG. 2 is a flowchart, and FIG. 3 is a diagram schematically illustrating the flow of air in a room where air conditioning is performed.

1 to 3, reference numeral 1 denotes a room for performing air conditioning, and a ceiling portion thereof has a ceiling-embedded air conditioner which can be independently operated by a control unit (not shown) having a built-in air conditioner in the room 1. The device 2 is mounted.
Reference numeral 3 denotes a cogeneration device (cogeneration unit), for example, a micro gas turbine 4 that operates using natural gas, naphtha, or the like as a fuel gas, a generator 5 that generates electric power by rotating the micro gas turbine 4, and a micro gas turbine. A gas heat exchanger 6 for extracting heat from the exhaust gas after operating the turbine 4 by using water as a heat medium and exchanging heat as exhaust heat;
Is connected to the outlet of the gas heat exchanger 6, and is provided with a pump 9 for discharging the heat medium to the outside from the outlet 7 and recovering the heat medium at the return port 8 of the gas heat exchanger 6 again. In addition, 5a
Reference numeral 4 denotes a power line for transmitting generated power, and reference numeral 4a denotes a gas pipe for supplying a fuel gas to the micro gas turbine 4.

In the lower part of the room 1, there are arranged a plurality of indoor units 10 for performing heat treatment of, for example, about 100 W / h by dissipating heat, and heat exchangers 10a of these indoor units 10 have heat exchangers 10a. The heat medium flows through the inflow pipe 12 so that the medium is distributed from the first flow control valves 11 connected to the discharge port 7 of the pump 9, and further flows through the heat exchanger 10 a of the indoor unit 10. However, they flow through the outflow pipe 13 and merge to return to the return port 8 of the gas heat exchanger 6.

A water heater 14 has a heat exchanger 14a in a hot water storage tank 14b.
The heat medium flows from the second flow control valve 15 connected to the discharge port 7 through the inflow pipe 16, and the heat medium after flowing through the water heater 14 flows through the outflow pipe 17 to flow through the gas heat exchanger 6.
To the return entrance 8. In addition, 18 is a water inlet pipe and 19 is a hot water outlet pipe. Furthermore, 20
Is a waste heat treatment apparatus provided with a heat exchanger 20a and a blower 20b for promoting heat exchange.
The heat medium flows from the third flow control valve 21 connected to the heat exchanger via the inflow pipe 22, and the heat medium after flowing through the heat exchanger 20a flows through the outflow pipe 23 to return to the gas heat exchanger 6. 8 is returned.

On the other hand, reference numeral 24 denotes a system control device comprising a microcomputer, which performs control based on the contents programmed in advance by signal lines 25a, 25b, 25c, and 25d indicated by broken lines for connection with each device. , 25e and exchanges signals.

That is, the system controller 24 controls, for example, the difference in the operation mode of the air conditioner 2 between the cooling operation and the heating operation, the strength of the cooling / heating air, and the opening of the first flow control valve 11 due to the temperature change of the room 1. Control or water heater 1
4, the opening control of the second flow control valve 15 for maintaining the temperature of the hot water, the opening control of the third flow control valve 21 corresponding to the amount of exhaust heat finally discarded to the environment, and the waste heat treatment apparatus. 20
Operation control and the like are performed.

With this configuration, when the cogeneration apparatus 3 is operated to generate electric power and the electric power is supplied through the power line 5a, the gas heat exchanger 6 is Then, the heat medium is heated, and when the pump 9 is started, the heated heat medium is sent to the first flow control valve 11, the second flow control valve 15, and the third flow control valve 21. The heat medium sets the opening of each of the flow control valves 11, 15, and 21 appropriately under the control of the system controller 24, so that the inflow pipes 12, 16, and
22.

The heat medium distributed and passed through the inflow pipe 12 via the first flow control valve 11 flows through the heat exchanger 10a of the indoor unit 10, and heat generated by natural convection of about 100 W / h per unit. The exhaust heat is treated by dissipation, and then the heat medium whose temperature has decreased flows through the outflow pipe 13 and returns to the return port 8 of the gas heat exchanger 6. Accordingly, a weak airflow is generated in the room 1 in which the air conditioning is performed.

At this time, when the air-conditioning apparatus 2 is in the cooling operation mode and blows cool air along the wall surface of the room, the cool air is opposite in the density difference and the rising airflow by the indoor unit 10. Then, the vehicle descends in the room according to the flow of the air, and is then sent to the upper part of the room by a weak ascending air current generated in the room, and is sucked into the air conditioner 2. Thereby, the inside of the room 1 is cooled to a uniform temperature.

Further, even when the air-conditioning apparatus 2 is in the heating operation mode, if the warm air is blown out slightly along the wall surface of the room, the warm air descends along the flow opposite to the upward airflow generated by the indoor unit 10. After that, the air is sent to the upper part of the room on the rising airflow and is sucked into the air conditioner 2. This allows
Room 1 is heated to a uniform temperature. The flow of air in the room 1 is as shown by the solid line in FIG.

On the other hand, the heat medium flowing through the inflow pipe 16 via the second flow control valve 15 is supplied to the heat exchanger 14 a of the water heater 14.
And heats the water in the hot water storage tank 14b, so that the exhaust heat transported by the heat medium is used. Thereafter, the heat medium whose temperature has decreased flows through the outflow pipe 17 to perform gas heat exchange. Return to the return port 8 of the vessel 6. In addition, the third
The heat medium flowing through the inflow pipe 22 via the flow control valve 21 flows into the heat exchanger 20a of the waste heat treatment apparatus 20, where the heat medium is transported by the heat medium so that heat exchange is promoted by the blower 20b. The discharged heat is discharged to the environment, and then the heat medium whose temperature has dropped is discharged to the outflow pipe 23.
And returns to the return port 8 of the gas heat exchanger 6.

Further, by changing the opening of the first flow control valve 11, the amount of heat medium flowing through the heat exchanger 10a of the indoor unit 10 is adjusted, and the amount of exhaust heat exchanged by the heat exchanger 10a is changed. Is changed, and the speed of the updraft generated in the indoor unit 10 can be changed. For this reason, at the time of the cooling operation, the opening degree of the first flow control valve 11 is set to the predetermined opening degree a, and the heat medium is supplied to the indoor unit 10.
To supply. As a result, as described above, the cool air blown out from the air conditioner 2 along the wall surface descends in the room along the flow opposite to the difference in density and the upward airflow by the indoor unit 10, and then is generated in the room. The air is sent to the upper part of the room on a weak rising airflow that is sucked into the air conditioner 2, and the inside of the room 1 is cooled to a uniform temperature.

On the other hand, during the heating operation, the first flow control valve 1
A predetermined opening b (b>
a), and supply a larger amount of heat medium to the indoor unit 10 than during the cooling operation. Accordingly, as described above, the warm air blown out from the air conditioner 2 along the wall surface has a small density and easily rises, but the rising airflow by the indoor unit 10 is stronger than that during the cooling operation. After descending the room along the opposite flow, the air is sent to the upper part of the room on an ascending airflow, sucked into the air conditioner 2, and the inside of the room 1 is heated to a uniform temperature.

This series of steps is executed under the control of the system controller 24 based on the flowchart shown in FIG. That is, the first step S ₁₁ determines the presence or absence of the system of operation requests have been made, if there is a request, the process proceeds to the second step. In a second step S _12, determination is the air conditioner 2 of whether or not the heating operation is performed, if it is not, the process proceeds to a third step S _13.
If no, the air conditioner is in cooling operation,
Adjusting At step S ₁₃ the opening of the first flow control valve 11 to a small predetermined opening a. Then, the fourth step S
Until it is determined in step ₁₄ that the operation stop command has been issued, the operation with the opening of the first flow control valve 11 kept small is continued.

Further, in the second step S _12, determination is the air conditioner 2 of whether or not the heating operation is made, in the case of the heating operation proceeds to a fifth step S _15. Adjusting the opening degree to a larger predetermined opening b (b> a) of the fifth step _{S 15} in the first flow control valve 11. Then, until it is determined that the command of the operation is stopped by the step S ₁₆ of the sixth is made, the operation in a state where the opening degree of the first flow control valve 11 and large opening is continued.

As described above, by adjusting the opening of the first flow control valve 11 in accordance with the air conditioning content of the air conditioner 2, the speed of the ascending airflow in the room 1 changes, and according to the operation mode, More comfortable air conditioning according to the strength of the cool and warm air can be realized. Furthermore, not only at the time of heating but also at the time of cooling, the exhaust heat of the cogeneration apparatus 3 is utilized, so that the exhaust heat finally discarded to the environment can be reduced and the echo generation apparatus 3 can be used.
The energy use efficiency of energy is improved, and the economic efficiency is also improved, and the amortization period of the energy can be shortened.

Next, a second embodiment will be described with reference to FIGS. FIG. 4 is a configuration diagram schematically showing the system, FIG. 5 is a plan view schematically showing a heating floor surface, and FIG.
Is a flowchart. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. The configuration of the present embodiment that is different from the first embodiment will be described.

In FIGS. 4 to 6, an air conditioner 2 with a built-in ceiling, which can be independently operated by a control unit (not shown) having a built-in air conditioner in the room 1, is provided on the ceiling portion of the room 1 for performing air conditioning. Installed. And
A panel-shaped floor heater 30 is laid on substantially the entire surface of the floor of the room 1. The floor heater 30 is, for example, 2
The heat exchanger 30a is composed of five small-panel heat exchangers 30a for dissipating heat. Each of the heat exchangers 30a receives a heat medium from the first flow control valve 11 connected to the discharge port 7 of the pump 9. It flows through the inflow pipe 12.

During the heating operation, the heat medium flows through all 25 heat exchangers 30a, and the entire floor is warmed. Further, during the cooling operation, the heat medium flows only through the four heat exchangers 30a provided at the center of the floor shown by hatching in FIG. 5 by switching by a switching valve (not shown), and a part of the floor is heated. ing.

Reference numeral 31 denotes a system control device including a microcomputer, which performs control based on the contents programmed in advance by signal lines 25a, 25c, 25d, and 25e shown by broken lines connecting the respective device devices. , 25f and exchanges signals.

That is, the system controller 31 controls, for example, the difference in the operation mode of the air conditioner 2 between the cooling operation and the heating operation, the intensity of the cooling / heating air, and the opening of the first flow control valve 11 due to the temperature change of the room 1. Control, furthermore, a part of the use of the heat exchanger 30a of the floor heater 30 depending on the difference between the cooling and the heating, the switching control of the entire use and the time period during which the heating is being performed are, for example, from 11 pm to 5:00 am (midnight). Or the first flow control valve 11 depending on whether it is a time zone other than
Is controlled. Further, the system controller 31 controls the opening degree of the second flow control valve 15 for maintaining the hot water temperature in the water heater 14, and furthermore, the third flow rate corresponding to the amount of exhaust heat to be finally discarded to the environment. The opening control of the control valve 21 and the operation control of the waste heat treatment apparatus 20 are performed.

With such a configuration, when the cogeneration apparatus 3 is operated to generate electric power and the electric power is supplied through the power line 5 a, the gas heat exchanger 6 is exhausted by the exhaust gas generated by the micro gas turbine 4. Then, the heat medium is heated, and when the pump 9 is started, the heated heat medium is sent to the first flow control valve 11, the second flow control valve 15, and the third flow control valve 21. The heat medium sets the opening of each of the flow control valves 11, 15, and 21 appropriately under the control of the system control device 31, so that each of the inflow pipes 12, 16, and
22.

The distributed heat medium flows through the inflow pipe 12 through the first flow control valve 11, flows through the heat exchanger 30a of the floor heater 30, and dissipates heat by natural convection. After that, the heat medium whose temperature has decreased flows through the outflow pipe 13 and returns to the return port 8 of the gas heat exchanger 6.
When heating the room 1, the heat medium flows through all the 25 heat exchangers 30 a, whereby the entire floor surface is warmed and the room 1 does not operate the air conditioner 2. Can be heated. In the case of the cogeneration device 3 having a power generation capacity of, for example, about 3 kW, since the heat output is 60% to 70% of the power generation capacity, usually, heating of one room can be performed only by using the exhaust heat. .

The air conditioner 2 may be used only when the heat output from the floor heater 30 is insufficient and the heating capacity is insufficient in a severely cold or cold area, or when heating a multi-room.
Is used in combination with the heating operation. Such an air conditioner 2
When the air conditioner is used in combination with the heating operation, the warm air generated by the floor heater 30 rises from the floor as an ascending airflow, and a weak ascending airflow is generated in the room 1. For this reason, the air conditioner 2
Then, when the warm wind is blown out along the wall surface, the warm wind descends along the flow opposite to the rising airflow by the floor heater 30, and then is sent to the upper part of the room on the rising airflow to the air conditioner 2. Inhaled. Thereby, the inside of the room 1 is heated to a uniform temperature. As a result, the rate of use of exhaust heat increases,
The utilization efficiency is improved, and the economy of the system is also improved.

On the other hand, when the air conditioner 2 is operated for cooling to cool the room 1, only the four heat exchangers 30a provided at the center of the floor of the floor heater 30 are switched by the switching valve. The heat medium flows, warm air rises from a part of the floor surface, and a weak air current is generated in the room 1. Accordingly, when the cool air from the air conditioner 2 is blown out along the wall surface of the room, the cool air descends the room along the flow opposite to the difference in density and the upward airflow by the floor heater 30. Thereafter, the passenger gets on the weak upward air current generated in the room, is sent to the upper part of the room, is sucked into the air conditioner 2, and is cooled to a uniform temperature in the room 1.

Further, the system controller 31
The opening degree of the first flow control valve 11 can be controlled depending on whether the time zone during heating is nighttime (midnight) or another time zone. This is intended to be performed based on the flowchart shown in FIG. 6, the determination of whether the system operation request is made in the first step S _21, when there is a request, the process proceeds to the second step. In a second step S _22, the determination of whether to carry out the heating is performed, in the case of performing the heating operation proceeds to a third step S _23.

[0036] In a third step S _23, the current, for example at night 5:00 am from 11 pm (midnight) is not time zone, i.e., the determination is made whether the daytime, when it is daytime proceeds to a fourth step _{S 24.} And
With adjusting to a large predetermined opening the opening of the fourth step S ₂₄ in the first flow control valve 11 is in a stopped state of the operation of the air conditioner 2. As a result, the room 1 is heated by the floor heater 30 using the exhaust heat. Thereafter, until it is determined that the command of the operation is stopped by the fifth step S ₂₅ is made, the remains stopped air conditioner 2 1
Heating by the floor heater 30 in a state where the opening of the flow control valve 11 is set to a large opening is continued.

Further, a third determination of whether the daytime in step S ₂₃ is performed, if the current is nighttime (midnight), the flow proceeds to step S ₂₆ of the sixth. Then, while adjusting the opening of the sixth step S ₂₆ in the first flow control valve 11 to a small predetermined opening, the air conditioner 2 to the heating operation state. As a result, the heating of the room 1 is mainly performed by the air conditioner 2 and the operation of the floor heater 30 is stopped only by generating a weak airflow. Thereafter, until it is determined that the command of the operation stop in the seventh step S ₂₇ is performed, in a state where the opening degree of the first flow control valve 11 to the small opening continues the heating operation by the air conditioner 2 .

As described above, by adjusting the ratio of the use of the exhaust heat of the cogeneration apparatus 3 at night (midnight) and other time zones as a whole, including the use of electric power by the electric power company, the total amount of CO2 is reduced. The amount of generation of carbon (CO ₂ ) can be suppressed. That is, the electric power of the electric power company during the daytime includes electric power generated by thermal power generation, so that a large amount of CO _{2 is} generated per unit electric power. For this reason, the utilization ratio of the exhaust heat of the cogeneration device 3 during the daytime, not at night (midnight), is increased.

Further, since the electric power of the electric power company at night (midnight) does not include the electric power generated by thermal power generation, the amount of CO ₂ generated per unit electric power is extremely small, and the cogeneration device 3 has a narrow output variable range. Unnecessary CO ₂ will be generated. For this reason, the usage ratio of the exhaust heat of the cogeneration device 3 at night (midnight) is reduced, and the air conditioner 2 uses the electric power of the electric power company to perform heating.

As described above, by adjusting the air conditioning content of the air conditioner 2 and the opening of the first flow control valve 11 in accordance with the difference between the heating and cooling of the room 1 and the time zone, etc.
The same effect as that of the embodiment can be obtained, and the amount of carbon dioxide (CO ₂ ) released to the environment can be reduced.

[0041]

As is apparent from the above description, according to the present invention, it is possible to effectively use exhaust heat while supplying power to a small-scale facility by using a cogeneration apparatus, and realize high energy use efficiency and high economic efficiency. And the like.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a system according to a first embodiment of the present invention.

FIG. 2 is a flowchart according to the first embodiment of the present invention.

FIG. 3 is a diagram schematically showing a flow of air in a room for performing air conditioning according to the first embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of a system showing a second embodiment of the present invention.

FIG. 5 is a plan view schematically showing a heating floor surface according to a second embodiment of the present invention.

FIG. 6 is a flowchart according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Room 2 ... Air conditioner 3 ... Cogeneration apparatus 10 ... Indoor unit 10a ... Heat exchanger

Claims (4)

[Claims] An air conditioner provided in a room for performing air conditioning, power is generated and power is supplied, and heat generated and discharged with power generation is extracted to the outside using a heat medium. An air conditioning system comprising: a cogeneration device; and a heat dissipation device that generates an upward airflow in the room by the discharged heat of the cogeneration device taken out by the heat medium. 2. The air conditioner according to claim 1, wherein the speed of the ascending airflow by the heat dissipation device is made variable in accordance with each of the cooling mode and the heating mode of the air conditioner. system. 3. The air conditioning system according to claim 1, wherein the heat dissipation device is provided on a floor in the room so as to heat the room. 4. The system according to claim 1, wherein, when heating the inside of the room, a utilization ratio of the heat discharged from the cogeneration device by the heat dissipation device is made variable in accordance with a period of operation. Air conditioning system.