JP2012016315A - Air-conditioning system for cultivation greenhouse - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air-conditioning system for a cultivation greenhouse capable of achieving reduction of a cost and carbon dioxide.SOLUTION: The air-conditioning system 1 for performing air-conditioning in the cultivation greenhouse H includes: an oil burning warm-air heater 2 installed in the cultivation greenhouse H; an indoor unit 31 installed in the cultivation greenhouse H; and a heat pump type air-conditioning device 3 having an outdoor unit installed outside the cultivation greenhouse H. The oil burning warm-air heater 2 stops when the temperature in the cultivation greenhouse H is higher than a first preset temperature which is set in advance and the heat pump type air-conditioning device 3 stops when the temperature in the cultivation greenhouse H is higher than a second preset temperature, which is set higher than the first set temperature in advance.

Description

  The present invention relates to an air conditioning system for a cultivation house that performs air conditioning in the cultivation house.

  Cultivation of crops using greenhouses such as plastic greenhouses and glass-walled greenhouses is widely carried out, but the temperature in the cultivation house has a great influence on the growth of crops, so it is necessary to control the temperature in the cultivation house There is. For example, Patent Literature 1 discloses that warm air generated by burning fuel such as heavy oil in the winter is supplied into the cultivation house to heat the cultivation house.

JP-A-10-117603

  However, the heating in the cultivation house using the heavy oil-fired hot air blower as described above has a problem that the cost increases due to the recent rise in the price of oil and the environmental problem due to the emission of carbon dioxide. There was a demand for reduction of carbon emissions. Then, this invention makes it a subject to provide the air conditioning system for cultivation houses which can aim at cost reduction and the reduction of a carbon dioxide.

  The air conditioning system for a cultivation house according to the present invention is an air conditioning system that performs air conditioning in the cultivation house, an oil-fired warm air machine installed in the cultivation house, an indoor unit installed in the cultivation house, and the above A heat pump type air conditioner having an outdoor unit installed outside the cultivation house, and the oil-fired warm air heater stops when the temperature in the cultivation house is equal to or higher than a first preset temperature set in advance. The heat pump air conditioner stops when the temperature is equal to or higher than a preset second set temperature higher than the first set temperature.

  According to this air conditioning system for a cultivation house, the inside of the cultivation house is heated not only by an oil-fired hot air machine but also by a heat pump type air conditioner. And when this oil-fired hot-air machine becomes more than 1st preset temperature, the heating operation stops, and when it is more than 1st preset temperature, it will be in the state which only the heat pump type air conditioner is working. . In this way, the oil-fired hot air blower serves only as a supplement to the heat pump air conditioner, and the heat pump air conditioner mainly performs air conditioning in the cultivation house, thereby reducing costs and reducing carbon dioxide emissions. be able to. In addition, the heat pump type air conditioner has a problem that if the heating operation is continuously performed, the heat exchanger portion (especially the fin portion) of the outdoor unit is frosted and the passage of outside air to the outdoor unit becomes worse. It is set to perform a defrosting operation when frost adheres. However, since this defrosting operation is an operation in which warm air is supplied from the outdoor unit side and cold air is supplied from the indoor unit side, if only the heat pump air conditioner is installed, the inside of the cultivation house There is a possibility that the temperature in the cultivation house will be lowered too much because it is not heated. On the other hand, in the air conditioning system according to the present invention, since the oil-fired warm air machine is also installed, the inside of the cultivation house can be heated even when the heat pump type air conditioner is performing a defrosting operation, The problem that the temperature in the cultivation house falls excessively can be prevented. In addition, this oil-fired hot air generator generates warm air by blowing the heat obtained by burning the fuel with a fan, such as a heavy oil-fired hot air fan, a kerosene-fired hot air machine, and a light oil-fired hot air machine. It is a concept that includes a device.

  Although the said air conditioning system for cultivation houses can take various structures, for example, it can be set as the structure which installs a fan apparatus in a cultivation house and circulates the air in a cultivation house with this fan apparatus. According to this structure, the temperature in a cultivation house can be equalized more efficiently.

  In addition, a plurality of the heat pump air conditioners described above are installed, and the fan described above in the vicinity of the indoor unit of each heat pump air conditioner so as to diffuse the hot air blown from the indoor unit of each heat pump air conditioner into the cultivation house It is good also as a structure which installs each apparatus. In this case, each fan device is controlled to stop during the defrosting operation of the corresponding heat pump air conditioner. By comprising in this way, it can prevent that a cold wind is spread | diffused in a cultivation house by a fan apparatus at the time of the defrost operation of a heat pump type air conditioner. In addition, it is preferable to control so that a heat pump type air conditioner may not perform a defrost operation simultaneously.

  Further, at least one of the first set temperature and the second set temperature may be set so that the set temperature at night is lower than the set temperature during the daytime. Compared to the daytime, the nighttime temperature does not affect crops so much, so lowering the set temperature at night can save more energy. Note that the set temperature at night at this time is preferably set to be 3 ° C. lower than the set temperature during the daytime.

  The first set temperature is preferably set to be 2 ° C. lower than the second set temperature.

  ADVANTAGE OF THE INVENTION According to this invention, the air conditioning system for cultivation houses which can aim at cost reduction and reduction of the discharge | emission amount of a carbon dioxide can be provided.

Drawing 1 is a top view showing arrangement of each device of the air conditioning system for cultivation houses concerning this embodiment. FIG. 2 is a schematic configuration diagram illustrating a state during the heating operation of the heat pump air conditioner according to the present embodiment. FIG. 3 is a schematic configuration diagram showing a state during a defrosting operation (cooling operation) of the heat pump air conditioner according to the present embodiment. FIG. 4 is a graph showing the relationship between the temperature in the cultivation house and the operating state of the heavy oil-fired hot air fan and the heat pump air conditioner. FIG. 5: is a perspective view which shows the outline of the cultivation house which concerns on an Example. Drawing 6 is a top view showing arrangement of each apparatus in a cultivation house in an example. FIG. 7 is a graph showing a temperature change in the cultivation house in Example 1. FIG. 7 is a graph showing changes in power consumption of each heavy oil-fired warm air machine and heat pump air conditioner in Example 1.

  Hereinafter, an embodiment of an air conditioning system for a cultivation house according to the present invention will be described with reference to the drawings. In the following description, the left-right direction in FIG. 1 is referred to as the longitudinal direction, and the up-down direction is referred to as the short-side direction, and the arrows in FIG. Moreover, below, it demonstrates on the assumption that the air conditioning system for cultivation houses is used for heating.

  As shown in FIG. 1, the cultivation house air conditioning system 1 is a system for performing air conditioning in the cultivation house H, and in this embodiment, two heavy oil-fired hot air machines 2 and four heat pump air conditioners. It is mainly composed of the device 3 and six fan devices 4.

  The cultivation house H employs a so-called vinyl house in which a synthetic resin film is coated on a framework formed of steel, wood, or the like so as to be an outer wall, and has a substantially rectangular shape in plan view. As the cultivation house H, a known one can be adopted.

  In the cultivation house H, the indoor units 31 of the heat pump type air conditioner 3 are arranged at the four corners, and the heavy oil-fired hot air machine 2 is installed between the indoor units 31 in the short direction. These heat pump type air conditioners 3 and heavy oil fired warm air machines 2 are arranged to send warm air toward the center side of the cultivation house H. Moreover, in the cultivation house H, the temperature sensor 5 for control which measures the temperature in the cultivation house H is installed, The installation place is a place as shown in FIG. Each can be installed in front of the blower 2 in the blowing direction.

The heavy oil-fired warm air machine 2 is an apparatus that generates heavy air by burning heavy oil, and conventionally known devices for heating in a cultivation house can be used. This heavy oil-fired hot air blower 2 is controlled by the control means (not shown) to start and stop the supply of hot air. Specifically, when the temperature in the cultivation house H detected by the control temperature sensor 5 is equal to or higher than the first preset temperature T ₁ set in advance, the supply of warm air is stopped, and the first preset temperature T _When it is less than ₁ , the control means controls so that the supply of hot air is started. The first set temperature T ₁ can be set so that the temperature differs between daytime and nighttime. For example, during the period from 6:00 am to 8:00 pm (daytime), when the control temperature sensor 5 detects that the temperature in the cultivation house H has become 13 ° C. or higher, the control means uses the heavy oil-fired hot air blower 2. The supply of hot air is stopped, and if it is less than 13 ° C., the supply of hot air is controlled to start, and the temperature in the cultivation house H is 10 ° C. from 8 o'clock to 6 am When it becomes above, supply of the warm air by the heavy oil fired warm air machine 2 can be stopped, and when it becomes less than 10 degreeC, it can control to start supply of a warm air.

  The heat pump type air conditioner 3 is mainly composed of an indoor unit 31 installed in the cultivation house H and an outdoor unit 32 installed outside the cultivation house H, and an air outlet formed in the indoor unit 31. Hot air (or cold air) is blown out. As shown in FIG. 2, the heat pump air conditioner 3 includes a compressor 301, a four-way switching valve 302, an indoor heat exchanger 303, an expansion valve (decompression mechanism) 304, and an outdoor heat exchanger 305 that are refrigerant pipes. Are connected in a ring shape, so that the refrigerant circulates inside. Of these, the indoor heat exchanger 303 is installed in the indoor unit 31, and the compressor 301, the four-way switching valve 302, the expansion valve 304, and the outdoor heat exchanger 305 are installed in the outdoor unit 32. Yes. The indoor unit 31 is formed with a suction port for sucking air in the cultivation house H, and the air sucked from the suction port is heat-exchanged with the refrigerant flowing in the indoor heat exchanger 303. During heating operation, the air exchanged with the refrigerant is heated and warm air is blown out from the outlet, and during defrosting operation (or during cooling operation), the air is cooled to become cold air and blown out from the outlet. It is configured.

The heat pump type air conditioner 3, the temperature of the cultivation house in H detected by the located control temperature sensor in the interior of the indoor unit 31, the second set temperature T ₂ above becomes the hot air to a preset supply is stopped, it is controlled by a control unit (not shown) so when it comes to the second set temperature T less than ₂ the supply of hot air is started. The second set temperature T ₂ is preferably higher by about 2 to 5 ° C. than the first set temperature T _1, more preferably about 2 ° C. Further, it can be a different temperature the second set temperature T ₂ in the daytime and nighttime. More specifically, for example, in the time zone from 6 am to 8 pm (daytime), the second set temperature T ₂ is set to 15 ° C, and in the time zone from 8 pm to 6 am (nighttime) The second set temperature T ₂ can be set to 12 ° C.

  In addition, as shown in FIG. 2, the heat pump type air conditioner 3 at the time of heating operation includes a compressor 301, a four-way switching valve 302, an indoor heat exchanger 303, an expansion valve 304, an outdoor heat exchanger 305, Since the four-way switching valve 302 and the compressor 301 flow in this order, the high-temperature refrigerant flows through the indoor heat exchanger 303 and the low-temperature refrigerant flows through the outdoor heat exchanger 305. If this heating operation continues, frost adheres to the outdoor heat exchanger 305 main body, fins, etc., and the flow of outside air to the outdoor heat exchanger 305 deteriorates. Therefore, a defrosting operation is performed to melt this frost. During this defrosting operation, the flow path in the four-way switching valve 302 is switched as shown in FIG. 3, and the refrigerant is the compressor 301, the four-way switching valve 302, the outdoor heat exchanger 305, the expansion valve 304, and the indoor side heat exchange. Since the refrigerant flows in the order of the condenser 303, the four-way switching valve 302, and the compressor 301, the high-temperature refrigerant flows through the outdoor heat exchanger 305, and the low-temperature refrigerant flows through the indoor heat exchanger 303.

  The fan device 4 is installed to circulate the hot air blown from the heat pump air conditioner 3 or the like in the cultivation house H, and is arranged in the vicinity of the indoor unit 31 of each heat pump air conditioner 3, More specifically, each of the indoor units 31 is arranged on the downstream side in the blowing direction. In addition, although it does not necessarily limit, it is preferable that the distance of the fan apparatus 4 and the indoor unit 31 shall be about 5-6m. Two fan devices 4 are installed not only in the vicinity of the indoor unit 31 but also in the central portion in the longitudinal direction. The fan device 4 arranged in the vicinity of each indoor unit 31 is controlled by control means (not shown) so as to stop when the corresponding heat pump type air conditioner 3 is in the defrosting operation. Moreover, it can also be set as the operation | movement which repeats an operation | movement and a stop of the fan apparatus 4 for every 15 minutes for energy saving.

  Next, the operation method of the air conditioning system for cultivation houses configured as described above will be described. In addition, below, the operation | movement method of the air conditioning system for cultivation houses in the time slot | zone of daytime (6 am to 8:00 pm) is demonstrated.

First, as shown in FIG. 4, when the temperature in the cultivation house H continues to decrease and becomes lower than the first set temperature T ₁ , supply of warm air from the heavy oil-fired warm air fan 2 is started. Since the temperature of the cultivation house in H than a second set temperature T ₂ at this time is low, it is supplied with hot air from the heat pump type air conditioner 3.

And if the temperature in the cultivation house H rises to _1st preset temperature T1 by supply of the warm air by the heavy oil fired warm air machine 2 and the heat pump type air conditioner 3, supply of the warm air by the heavy oil fired hot air machine 2 stops. Only the heat pump type air conditioner 3 is in a state of supplying hot air. When the temperature in the cultivation house H further rises to the _second set temperature T ₂ by supplying only the heat pump type air conditioner 3, the supply of the hot air by the heat pump type air conditioner 3 is stopped, and the heat pump type air conditioner 3. And the heavy oil fired hot air machine 2 are in a state in which the supply of hot air is stopped. When the wherein the second set temperature T lower than ₂ the temperature drops in the cultivation house H, again, the supply of hot air by the heat pump type air conditioning device 3 is started.

As described above, according to the cultivation house air conditioning system 1 according to the embodiment, fuel oil-fired hot air machine 2, if less than a first set temperature T ₁ of the hot air supply is not performed, basically a heat pump type air conditioning Since it is an auxiliary role for the apparatus 3, it is possible to reduce carbon dioxide emissions and reduce costs.

As mentioned above, although embodiment of this invention was described, this invention is not limited to these, A various change is possible unless it deviates from the meaning of this invention. For example, in the said embodiment, although demonstrated only about the case where the inside of a cultivation house was heated, the inside of a cultivation house can also be cooled. In this case, cold air can be provided in the cultivation house H by stopping the heavy oil fired hot air fan 2 and operating the heat pump air conditioner 3 in the same manner as the defrosting operation described above. In this case, when the temperature becomes lower than the third set temperature T ₃ , the supply of the cold air by the heat pump air conditioner 3 is stopped, and when the temperature becomes equal to or higher than the third set temperature T ₃ , the control means controls the cold air to be supplied. For example, the third set temperature T ₃ can be set to about 20 ° C.

In addition, the first set temperature T ₁ and the second set temperature T ₂ in the above embodiment are not particularly limited, and may be changed depending on the crop to be cultivated.

  Moreover, the control means for controlling the stop and operation of the heavy oil-fired hot air blower 2, the heat pump type air conditioner 3 and the fan device 4 may be incorporated in each device one by one or all by one control means. It is good also as a structure which controls this apparatus. In addition, a plurality of devices are controlled by one control means (for example, each device on the left side of FIG. 1 is controlled by the first control unit, and each device on the right side of FIG. Or the like).

  Moreover, in the said embodiment, although the heavy oil-fired warm air machine 2 which used heavy oil as the fuel is employ | adopted, the warm air machine which uses light oil, kerosene, etc. as a fuel is also employable.

  The present invention will be described more specifically with reference to the following examples and comparative examples. In addition, this invention is not limited to the following Example.

Example 1
As shown in FIG. 5, the cultivation house has a length d in the longitudinal direction of 78 m, a length w in the short direction of 16 m, a ceiling height h ₁ of 6.35 m, and an eave height h ₂ of 2.2 m. Yes, it is formed of two layers of polyethylene film. As the heavy oil fired hot air blower 2 arranged on the left side of FIG. 1, a house kaonki HK-4025 made by Nepon is used, and as the heavy oil fired hot air blower 2 arranged on the right side, a house kaonki HK- made by Nepon Co., Ltd. is used. 2025 was used. Moreover, as the heat pump type air conditioner 3, a floor-mounted type air conditioner PSZN-ERP160GB made by Mitsubishi Electric Co., Ltd. was adopted. The fan device 4 is a straight power fan PF-H35CTC manufactured by Sowa Technica Co., Ltd. In order to measure the temperature in this cultivation house, temperature sensors TH1-1 to TH1-12 were installed at a total of 12 locations, and the outside air temperature was measured by the temperature sensor TH1-13. In addition, arrangement | positioning of each apparatus in the cultivation house H was as FIG. The temperature sensors TH1-1 to 1-8 measure the temperature at a height of 1.5 m from the floor, and the temperature sensors TH1-9 to 1-12 arranged at the center of the cultivation house are 4 at a pitch of 500 mm from the floor. The spot temperature was measured.

  In the time zone from 6:00 am to 8:00 pm (daytime), the heat pump type air conditioner 3 is set to stop when it reaches 15 ° C. or higher and to operate when it becomes less than 15 ° C., and the heavy oil fired hot air blower 2 becomes 12 ° C. or higher. It set so that it might operate when it stopped and it became less than 12 ° C. Moreover, in the time zone (nighttime) from 8:00 to 6:00 in the morning, the heat pump type air conditioner 3 is set to stop when the temperature is 12 ° C. or higher and to operate when the temperature is lower than 12 ° C. The temperature was set to stop when the temperature was higher than 10 ° C. and to operate when the temperature was lower than 10 ° C.

  FIG. 7 shows a graph of the temperature change for each time at each measurement point in the cultivation house H under the above conditions, and FIG. 8 shows a graph of the power consumption by this air conditioning system.

  Table 1 shows the running cost of each heat pump air conditioner.

  Moreover, since the temperature in the cultivation house did not fall below 10 ° C. in this example, each heavy oil-fired warm air fan 2 is not operating and the running cost is 0 yen. Therefore, the running cost of the air conditioning system of the embodiment is 1185 yen / day.

(Comparative Example 1)
As Comparative Example 1, the same air conditioning system as in Example 1 was used in the same cultivation house adjacent to Example 1, but the heat pump type air conditioner 3 was not used, and only the heavy oil-fired hot air machine 2 was used. Moreover, this heavy oil-fired hot air machine 2 was performed under the same conditions as in Example 1, that is, only under 13 ° C. during the day and only under 10 ° C. during the night. Table 2 shows the running cost of the air conditioning system in Comparative Example 1.

  Thus, the running cost of the air conditioning system of Comparative Example 1 was 2765 yen / day, and Example 1 was found to be lower in cost than Comparative Example 1.

DESCRIPTION OF SYMBOLS 1 Air conditioning system for cultivation house 2 Heavy oil fired warm air machine 3 Heat pump type air conditioner 31 Indoor unit 32 Outdoor unit 4 Fan apparatus H Cultivation house

Claims (7)

An air conditioning system for air conditioning in a cultivation house,
An oil fired warm air machine installed in the cultivation house;
A heat pump type air conditioner having an indoor unit installed in the cultivation house and an outdoor unit installed outside the cultivation house,
The oil-fired warm air heater stops when the temperature in the cultivation house is equal to or higher than a first preset temperature set in advance,
The heat pump air conditioner is an air conditioning system that stops when the temperature is equal to or higher than a second preset temperature that is higher than the first preset temperature.   The air conditioning system according to claim 1, further comprising a fan device that is installed in the cultivation house and circulates air in the cultivation house. A plurality of the heat pump type air conditioners are installed,
The fan device is installed in the vicinity of the indoor unit of each heat pump air conditioner so as to diffuse the hot air blown from the indoor unit of each heat pump air conditioner into the cultivation house,
Each said fan apparatus is an air conditioning system of Claim 2 stopped at the time of the defrost driving | operation of the said said heat pump type | formula air conditioner.   The air conditioning system according to any one of claims 1 to 3, wherein at least one of the first set temperature and the second set temperature has a night set temperature lower than a day set temperature.   The air conditioning system according to claim 4, wherein the nighttime set temperature is 3 ° C. lower than the daytime set temperature.   The air conditioning system according to any one of claims 1 to 5, wherein the first set temperature is 2 ° C lower than the second set temperature.   The air conditioning system according to any one of claims 1 to 6, wherein a plurality of the heat pump air conditioners are installed, and each heat pump air conditioner is controlled not to perform a defrosting operation at the same time.

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