JP2010220560A - Plant cultivation greenhouse, and thermal storage method in the greenhouse - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a greenhouse improved in heat collection efficiency to obtain a sufficient amount of stored heat. <P>SOLUTION: The greenhouse includes: a light-transmissive partition means 1 partitioning the inner space of the greenhouse into an upper chamber 6a and a lower chamber 6b; an air outlet 2 set up to the upper chamber 6a; an air inlet 3 set up to the upper chamber 6a; a heat pump 4 generating cool air to be exhausted through the air outlet 2, and taking out the heat each from gas sucked in through the air inlet 3; and a thermal storage medium 5 for storing the heat taken out by the heat pump 4. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a greenhouse for plant cultivation and a heat storage method in the greenhouse.

  Conventionally, a greenhouse for plant cultivation using a heat pump is known (see Patent Document 1 below). However, the heat pump is only used as a heater for raising the room temperature at night.

  On the other hand, there is known a greenhouse in which indoor air heated by sunlight is guided to a heat exchanger, heat is extracted by the heat exchanger, and heat is stored in a heat storage medium such as water. This greenhouse is intended to prevent the nighttime indoor temperature from being lowered by the heat released from the heat storage medium. However, in order to obtain a sufficient amount of heat storage in such a greenhouse, high-temperature air is required to improve the heat exchange performance. However, increasing the temperature in the room increases the temperature difference from the outside temperature. Therefore, the amount of heat released to the outside increases, which is inefficient with respect to heat collection. Moreover, since indoor high temperature will have a bad influence on a cultivation plant, indoor temperature cannot also be raised excessively. Therefore, the conventional greenhouse cannot obtain a sufficient amount of heat storage enough for room heating at night.

JP-A-5-336847

  The problem to be solved by the present invention is to provide a greenhouse and a heat storage method capable of improving heat collection efficiency and obtaining a sufficient amount of heat storage.

In order to solve the above-mentioned problems, the present invention provides the following greenhouse for plant cultivation and a heat storage method in the greenhouse.
1. A greenhouse for plant cultivation, a light-transmitting partition means that divides the internal space of the greenhouse into an upper chamber and a lower chamber, an exhaust port provided in the upper chamber, an intake port provided in the upper chamber, and the intake air A greenhouse comprising: a heat pump that generates cold air discharged from the exhaust port from a gas sucked from the port, and that extracts heat; and a heat storage medium that stores heat extracted by the heat pump.
2. 2. The greenhouse according to 1 above, wherein the exhaust port is provided so as to form a flow of cold air along the roofing material.
3. 3. The greenhouse according to 1 or 2, wherein the partition means can be opened and closed.
4). A method for storing heat in a greenhouse for plant cultivation, wherein an internal space of the greenhouse is separated into an upper chamber and a lower chamber by a light-transmitting partition means, a heat pump is operated, and the gas in the upper chamber is provided in the upper chamber. The air is sucked into the heat pump through the intake port, cold air is generated from the gas by the heat pump, the cold air is discharged to the upper chamber through the exhaust port provided in the upper chamber, and the heat pump Extracting heat from the gas and storing the heat in a heat storage medium.
5). 5. The method according to 4 above, wherein the cool air generated by the heat pump is discharged so as to form a cool air flow along the roofing material.
6). 6. The method according to 4 or 5, wherein the partitioning means is opened in response to a temperature rise in the lower chamber.

In the present invention described in 1 above, since the partition means for separating the internal space of the greenhouse into the upper chamber and the lower chamber has light permeability, it is possible to sufficiently incorporate sunlight necessary for the cultivated plant into the lower chamber. Become. The air in the lower chamber is heated and raised by the heat generated by irradiating sunlight to the cultivated plants, the cultivation floor, and the cultivation equipment existing in the lower chamber, and warms the partitioning means. The air in the upper chamber is warmed by the heat released from the partition means. The present invention includes an exhaust port provided in the upper chamber, an intake port provided in the upper chamber, and a heat pump that generates cool air discharged from the exhaust port from gas sucked from the intake port and extracts heat. Therefore, by operating the heat pump, the gas in the upper chamber is sucked into the heat pump through the intake port, cold air is generated from the gas by the heat pump, and the cold air is discharged to the upper chamber through the exhaust port. Is possible. Moreover, since it is possible to prevent the cool air from flowing out to the lower chamber by the partitioning means, the air in the upper chamber can be effectively cooled. Thereby, since the temperature difference between the air in the upper chamber and the outside air can be reduced, the amount of heat released to the outside is reduced. Further, in the present invention, the heat pump extracts heat from the gas sucked from the intake port in such a state, and thus is very efficient with respect to heat collection. Moreover, since this invention is equipped with the heat storage medium for storing the heat taken out with the heat pump, it becomes possible to store sufficient quantity of heat in this heat storage medium.
In the present invention described in 2 above, since the exhaust port is provided so as to form a flow of cool air along the roof material, the temperature difference between the inside and the outside of the roof material can be efficiently reduced. Accordingly, it is possible to effectively reduce the amount of heat released to the outside through the roofing material.
According to the third aspect of the present invention, since the partition means can be opened and closed, when the temperature of the lower chamber becomes excessively high, by opening the partition means, the cool air discharged from the exhaust port is allowed to enter the lower chamber. The temperature of the lower chamber can be lowered by letting it flow out. Thereby, the temperature of the lower chamber can be controlled.
According to the present invention described in 4 above, similar to the invention described in 1 above, it is possible to improve the heat collection efficiency and obtain a sufficient amount of heat storage.
According to the present invention described in 5 above, similarly to the invention described in 2 above, the amount of heat released to the outside through the roof material by effectively reducing the temperature difference between the inside and outside of the roof material. Can be effectively reduced.
According to the present invention described in 6 above, similarly to the invention described in 3 above, it is possible to cause the cool air discharged from the exhaust port to flow out into the lower chamber and to lower the temperature of the lower chamber, thereby It becomes possible to control the temperature of the lower chamber.

FIG. 1 is a schematic side view illustrating a greenhouse structure according to an embodiment of the present invention. FIG. 2 is a schematic front view showing a greenhouse structure according to an embodiment of the present invention. FIG. 3 is a schematic view showing a state in which the partition means is half-opened in the greenhouse according to one embodiment of the present invention. FIG. 4 is a schematic view showing a state in which the partition means is fully opened in the greenhouse according to one embodiment of the present invention. FIG. 5 is a schematic front view showing a greenhouse structure according to an experimental example of the present invention. FIG. 6 is a graph showing the temperature characteristics of the greenhouse according to the experimental example of the present invention. FIG. 7 is a schematic front view showing a greenhouse structure according to a comparative experimental example. FIG. 8 is a graph showing the temperature characteristics of a greenhouse according to a comparative experimental example.

  Hereinafter, embodiments of the present invention will be described with reference to the examples shown in the drawings. However, the embodiments of the present invention are not limited to these examples.

  1 and 2 are schematic views illustrating a greenhouse structure according to an embodiment of the present invention. As shown in these drawings, the greenhouse according to the present embodiment includes a partition unit 1, an exhaust port 2, an intake port 3, a heat pump 4, and a heat storage medium 5.

  The partition means 1 plays a role of separating the internal space of the greenhouse into the upper chamber 6a and the lower chamber 6b. Here, the lower chamber 6b is a place that functions as a plant cultivation room. The partition means 1 has light permeability. As the partition means 1, for example, a light transmissive film can be used. It is preferable that the partition means 1 can be opened and closed. In this embodiment, the partition means 1 is attached to the wire 7 that is stretched at the same height as the greenhouse beam, and the partition means 1 can be opened and closed along the wire 7 (FIGS. 3 and 3). 4).

  The exhaust port 2 is provided in the upper chamber 6a. The exhaust port 2 is preferably provided so as to form a flow of cold air along the roofing material 8. In the present embodiment, a large number of exhaust ports 2 are formed in a portion extending to the upper chamber 6a of the first pipe 9 (see FIG. 1). The first pipe 9 is connected to the heat pump 4 and functions as a means for transferring cold air generated by the heat pump 4 (see FIG. 1). The portion of the first pipe 9 that extends to the upper chamber 6a is arranged along the ridge directly below the greenhouse ridge (the top of the roof), and the numerous exhaust ports 2 respectively face the ridge. (See FIG. 1). By providing the exhaust port 2 as described above, the cold air discharged from the exhaust port 2 flows along the roofing material 8 (see FIGS. 2 to 4). Here, the roofing material 8 is comprised with light transmissive materials, such as a glass plate and a plastic film, like a general greenhouse.

  The intake port 3 is provided in the upper chamber 6a. In the present embodiment, a large number of intake ports 3 are formed in a portion extending to the upper chamber 6a of the second pipe 10 (see FIG. 1). The 2nd piping 10 is connected to the heat pump 4, and functions as a transfer means of the gas attracted | sucked from the inlet port 3 (refer FIG. 1). The portion of the second pipe 10 that extends to the upper chamber 6a is below the first pipe 9 and extends in the same direction as the direction in which the first pipe 9 extends (see FIG. 1). A large number of intake ports 3 are formed on both sides of a portion of the second pipe 10 that extends to the upper chamber 6a (see FIGS. 2 to 4).

  The heat pump 4 has a function of generating cold air discharged from the exhaust port 2 from a gas sucked from the air inlet 3 and a function of extracting heat from the gas sucked from the air inlet 3. In this embodiment, an electric heat pump is used. The heat pump 4 sucks gas from the upper chamber 6a through the intake port 3, exchanges heat with the refrigerant by an evaporator, then compresses the refrigerant with a compressor to increase the temperature, and then heats with a condenser. Is removed (that is, the heat storage medium 5 is heated), the pressure is rapidly reduced by the expansion valve to lower the temperature, and then the cool air is generated by the evaporator.

  The heat storage medium 5 is for storing heat extracted by the heat pump 4. As the heat storage medium 5, a liquid such as water can be used. In the present embodiment, the heat storage medium 5 is placed in a container capable of releasing heat stored in the heat storage medium 5 to the outside, and is disposed under the lower chamber 6b (see FIGS. 1 to 4). The heat stored in the heat storage medium 5 is released to the lower chamber 6b, thereby preventing the temperature of the lower chamber 6b from decreasing at night or the like.

  The greenhouse configured as described above operates as follows. That is, as shown in FIG. 2, when the partition unit 1 is fully closed, the internal space of the greenhouse is divided into the upper chamber 6 a and the lower chamber 6 b by the partition unit 1. Sunlight incident on the greenhouse is reflected and absorbed by the roof material surface and is transmitted through the roof material. The absorbed component raises the temperature of the roofing material and is released as heat to the outside air, and warms the air in the upper chamber 6a. A part of the permeated portion directly warms carbon dioxide gas or water vapor in the air in the upper chamber 6 a, but most of the permeated portion is incident on the partition means 1. This incident amount is reflected and absorbed by the surface of the partition unit 1 and is transmitted through the partition unit 1. The sunlight reflected on the surface of the partition means 1 warms the air in the upper chamber 6a while being repeatedly reflected in the upper chamber 6a. The absorbed component raises the temperature of the partition means 1 and is released as heat to the upper chamber 6a and the lower chamber 6b, thereby warming the air in the upper chamber 6a and the lower chamber 6b. The sunlight that has passed through the partition means 1 irradiates the cultivated plant, the cultivation floor, the cultivation instrument, and the like existing in the lower chamber 6b. Here, since the partition means 1 has light transmittance, the sunlight necessary for the cultivated plant can be sufficiently taken into the lower chamber 6b.

  The air in the lower chamber 6b is warmed and raised by heat generated by irradiating the cultivated plant with sunlight, and warms the partition means 1. The air in the upper chamber 6 a is warmed by the heat released from the partition means 1.

  In this state, when the heat pump 4 is operated, the gas warmed by the sunlight in the upper chamber 6a is sucked into the heat pump 4 through the intake port 3, the heat pump 4 extracts heat from the gas, and the heat is stored. It can be stored in the medium 5. According to the greenhouse according to the present embodiment, the gas heated by the sunlight in the upper chamber 6a becomes the heat source of the heat pump 4, and therefore, a high coefficient of performance (for example, a heat pump using low temperature outside air (10 ° C. or lower) as the heat source. In comparison with the coefficient of performance of 150% or more), and there is an advantage that power consumption is small. Further, the heat pump 4 generates cold air from the gas, and discharges the cold air to the upper chamber 6 a through the exhaust port 2. The air in the upper chamber 6a is cooled by this cold air, and the temperature decreases. In the present embodiment, since the exhaust port 2 is provided so as to form a flow of cold air along the roof material 8, even when the outside air temperature is low, the temperature difference between the inside and the outside of the roof material 8 can be efficiently performed. Can be small. Therefore, even when the temperature in the vicinity of the center of the upper chamber 6a (the portion excluding the vicinity of the roof material 8) is high, the amount of heat released to the outside through the roof material 8 can be effectively reduced. Furthermore, the partition means 1 can prevent the cool air from flowing out into the lower chamber 6b. Since the heat pump 4 extracts heat from the gas sucked from the air inlet 3 in such a state, it is very efficient with respect to heat collection. As a result, a sufficient amount of heat can be stored in the heat storage medium 5 even in winter when the sunshine hours are short.

  On the other hand, when the temperature of the lower chamber 6b becomes excessively high, the partition means 1 is opened (see FIGS. 3 and 4). Thereby, the cool air discharged from the exhaust port 2 can flow out into the lower chamber 6b, the temperature of the lower chamber 6b can be lowered, and the temperature of the lower chamber 6b can be controlled. The degree of opening of the partition means 1 can be appropriately adjusted according to the temperature of the lower chamber 6b.

(Experimental example)
The temperature characteristics were verified using the greenhouse shown in FIG. Although the greenhouse which concerns on the said Example is a continuous building type, the greenhouse which concerns on an experiment example is a single building type. Similarly to the greenhouse according to the example, the greenhouse according to the experimental example includes a light transmissive partition means 1 that divides the interior space of the greenhouse into an upper chamber 6a and a lower chamber 6b, an exhaust port 2 provided in the upper chamber 6a, and an upper portion. An intake port 3 provided in the chamber 6a, a heat pump for generating cold air discharged from the exhaust port 2 from the gas sucked from the intake port 3, and a heat pump for extracting heat, and for storing heat extracted by the heat pump And a heat storage medium 5. In the experiment, the outside air and the temperatures of the upper chamber 6a and the lower chamber 6b were measured for 24 hours.

  FIG. 6 is a graph showing experimental results (temperature characteristics). As shown in this graph, before starting the operation of the heat pump (time zone from 7 o'clock to 9 o'clock), the temperature of the upper chamber 6a and the lower chamber 6b is changed to the outside air by irradiating the greenhouse with sunlight. It rose rapidly compared to the temperature.

  In the time zone from 9 o'clock to 10 o'clock immediately after the start of the operation of the heat pump, the temperature of the upper chamber 6a suddenly decreased to 2 to 3 ° C lower than the temperature of the outside air. This indicates that the upper chamber 6a is cooled by the cold air discharged from the exhaust port 2. On the other hand, the temperature of the lower chamber 6b continued to rise to around 30 ° C. This indicates that the partition means 1 prevents the cool air from flowing into the lower chamber 6b.

  In the time zone from 10:00 to 13:00, the temperature of the outside air, the upper chamber 6a, and the lower chamber 6b continued to rise. The temperature of the outside air, the upper chamber 6a, and the lower chamber 6b reached a peak around 13:30. In this experiment, the temperature at the peak of the lower chamber 6b is as high as 42 ° C. This is because the greenhouse is a single building type, so that sunlight is irradiated not only from the roof surface but also from the side surface. This is considered as one of the causes. In the multi-storey greenhouse as in the example, most of the sunlight is irradiated from the roof surface, so the temperature of the lower chamber 6b does not become high as in the experimental example. The same applies to the peak temperature of the upper chamber 6a.

  In the time zone from 14:00 to 16:00, the temperature of the outside air, the upper chamber 6a, and the lower chamber 6b continued to decrease. The heat pump operation ended at 16:00.

  When the heat pump is not operated during the time period in which sunlight is irradiated, the temperature of the upper chamber 6a is increased similarly to the temperature of the lower chamber 6b, and the temperature difference from the outside air is increased. By operating it, the temperature difference between the upper chamber 6a and the outside air could be reduced. Therefore, it was proved from this result that the amount of heat released to the outside decreased.

  Further, since the upper chamber 6a and the lower chamber 6b are separated by the partition means 1, the outflow of cold air to the lower chamber 6b is prevented, so that the temperature of the lower chamber 6b reaches the peak until the temperature of the lower chamber 6b reaches the peak. There was no decrease in temperature. As a result of this, it is not desirable to suddenly lower the temperature when cultivating the plant, but even if the temperature of the upper chamber 6a is drastically lowered by the action of the partition means 1, the temperature of the lower chamber 6b is not affected. Proven from.

  In the time zone from 16:00 to 16:30 immediately after the operation of the heat pump was finished, the temperature of the upper chamber 6a increased, but in the subsequent time zone (from 16:30 to 1 o'clock the next day) Since the temperature of 6a was not irradiated with sunlight, it continued to fall until it became the same temperature as the temperature of outside air.

  On the other hand, the temperature of the lower chamber 6b is in the range of 10 to 15 ° C. while the temperature of the outside air is about 5 ° C. in the time zone where there is no sunlight irradiation (from 19:00 to 3 o'clock on the next day). Maintained. This has shown that the temperature fall of the lower chamber 6b could be prevented by the heat radiation from the heat storage medium 5, and from this result, sufficient heat can be stored in the heat storage medium 5 during the operation of the heat pump. Has been demonstrated.

(Comparative experiment example)
FIG. 7 is a schematic view of a greenhouse according to the comparative experiment example, and this greenhouse differs from the greenhouse according to the experiment example in that the partition means 1 is not provided. That is, in this greenhouse, the entire interior space of the greenhouse is a single room 6c. In the comparative experiment, the temperature of the outside air and the chamber 6c was measured for 24 hours.

  FIG. 8 is a graph showing the results (temperature characteristics) of the comparative experiment. As shown in this graph, the temperature of the chamber 6c rapidly decreased in the time zone from 9 o'clock to 10 o'clock immediately after the operation of the heat pump was started. This indicates that the temperature around the cultivated plant is drastically reduced by the cold air discharged from the exhaust port 2 because there is no partition means 1. In this respect, in the above experimental example, the partition means 1 can prevent a rapid decrease in the temperature of the lower chamber 6b, so that a favorable environment can be provided for the cultivated plant.

DESCRIPTION OF SYMBOLS 1 Partition means 2 Exhaust port 3 Intake port 4 Heat pump 5 Heat storage medium 6a Upper chamber 6b Lower chamber 6c Chamber 7 Wire 8 Roof material 9 1st piping 10 2nd piping

Claims (6)

A greenhouse for plant cultivation,
A light transmissive partitioning means for separating the internal space of the greenhouse into an upper chamber and a lower chamber;
An exhaust port provided in the upper chamber;
An air inlet provided in the upper chamber;
A heat pump that generates cool air discharged from the exhaust port from gas sucked from the intake port, and extracts heat.
A greenhouse comprising a heat storage medium for storing heat extracted by the heat pump.   The greenhouse according to claim 1, wherein the exhaust port is provided so as to form a flow of cold air along the roofing material.   The greenhouse according to claim 1 or 2, wherein the partition means is openable and closable.   A method for storing heat in a greenhouse for plant cultivation, wherein an internal space of the greenhouse is separated into an upper chamber and a lower chamber by a light-transmitting partition means, and then a heat pump is operated, and the gas in the upper chamber is provided in the upper chamber. The air is sucked into the heat pump through the intake port, cold air is generated from the gas by the heat pump, the cold air is discharged to the upper chamber through the exhaust port provided in the upper chamber, and the heat pump Extracting heat from the gas and storing the heat in a heat storage medium.   The method according to claim 4, wherein the cool air generated by the heat pump is discharged so as to form a cool air flow along the roofing material.   6. The method according to claim 4, wherein the partitioning means is opened in response to a temperature rise in the lower chamber.

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