JP7453667B2 - Gas supply device, gas supply method, and storage medium - Google Patents

Description

The present disclosure relates to a gas supply device, a gas supply method, and a storage medium.

Patent Document 1 discloses a plant growth environment control device that controls a plant growth environment in a facility where plants are grown using sunlight. This plant growth environment control device includes a timer that counts the plant time based on the sunrise time and sunset time stored in the storage part, and a plant growth environment control device that controls the daily plant growth in the facility based on the plant time counted by the timer. and a control unit that controls the environment. The control unit controls the supply of carbon dioxide within the facility based on plant time.

Patent Document 2 describes a carbon dioxide system that controls a carbon dioxide generator that generates carbon dioxide to be supplied into a greenhouse based on the carbon dioxide concentration in the greenhouse measured by a carbon dioxide concentration sensor installed near plants. A carbon dioxide application system having a controller is disclosed. This carbon dioxide application system includes a control means that prevents the carbon dioxide generator from supplying carbon dioxide when the time measured by the timer is not within a predetermined range.

JP2015-223118A Japanese Patent Application Publication No. 2018-134104

The present disclosure provides a gas supply device, a gas supply method, and a storage medium that can efficiently supply gas containing carbon dioxide.

A gas supply device according to one aspect of the present disclosure includes a supply unit that includes a material that absorbs or adsorbs and releases carbon dioxide, and supplies a gas containing carbon dioxide toward a cultivation area where plants are cultivated; A control unit that adjusts the amount of gas supplied based on time during the gas supply period. The control unit determines, on a daily basis, that the cumulative amount of carbon dioxide supplied after the intermediate time during which the predicted value of the amount of carbon dioxide absorbed by plants during the supply period is at its maximum is the amount of carbon dioxide up to the intermediate time during the supply period. Adjust the gas supply amount so that it is 1/3 to 3 times the cumulative supply amount. With this gas supply device, the amount of carbon dioxide released from the material per unit time can be made larger before and after the intermediate time when the predicted value of the amount of carbon dioxide absorbed is the maximum, than at other times. Therefore, it becomes possible to efficiently supply gas containing carbon dioxide.

The control unit may adjust the amount of gas supplied on a daily basis so that gas containing carbon dioxide that is 70% or more of the amount stored by the material is supplied to the cultivation unit during the supply period. In this case, the amount of gas containing carbon dioxide supplied during the entire supply period can be maintained at a certain value or more. Therefore, it becomes possible to supply gas containing carbon dioxide more efficiently.

The control unit adjusts the amount of gas supplied by changing the ratio of the time during which the gas supply is continued and the time during which the gas supply is stopped in each of a plurality of divided periods obtained by dividing the supply period. You can. In this case, the amount of gas supplied can be adjusted using a device that can switch between two states: a state in which gas is supplied and a state in which gas supply is stopped, which simplifies the device configuration and reduces the processing load on the control unit. This makes it possible to reduce the

The control unit may set the start time and end time of the supply period based on the position information of the cultivation unit. In this case, gas can be supplied in an appropriate period according to the movement of the sun at the position of the cultivation area, so it becomes possible to supply gas containing carbon dioxide more efficiently.

A gas supply method according to one aspect of the present disclosure is a method of supplying a gas containing carbon dioxide to a cultivation area where plants are grown through a material that absorbs or adsorbs and releases carbon dioxide. This gas supply method includes adjusting the gas supply amount based on time during the gas supply period. Adjusting the gas supply amount on a daily basis means that the cumulative amount of carbon dioxide supplied after the midpoint of the supply period when the predicted value of the amount of carbon dioxide absorbed by plants is at its maximum is This includes adjusting the amount of gas supplied so that it is 1/3 to 3 times the cumulative amount of carbon dioxide supplied up to the time. In this case, like the above-mentioned gas supply device, it becomes possible to efficiently supply gas containing carbon dioxide.

A storage medium according to one aspect of the present disclosure is a computer-readable storage medium that stores a program for causing an apparatus to execute the above gas supply method.

According to the present disclosure, a gas supply device, a gas supply method, and a storage medium that can efficiently supply gas containing carbon dioxide are provided.

FIG. 1 is a schematic diagram showing an example of a plant cultivation system including a gas supply device. FIG. 2 is a schematic diagram showing an example of an operating state in absorption mode. FIG. 3 is a schematic diagram showing an example of the operating state in the first discharge mode. FIG. 4 is a schematic diagram showing an example of the operating state in the second release mode. FIG. 5 is a graph showing changes over time in the amount of carbon dioxide released in the comparative example. FIG. 6 is a graph showing changes over time in the amount of carbon dioxide released when the supply amount is adjusted. FIG. 7 is a block diagram showing an example of the functional configuration of the control section. FIG. 8 is a block diagram showing an example of the hardware configuration of the control section. FIG. 9 is a flowchart showing an example of a gas supply method. FIG. 10 is a flowchart illustrating an example of gas supply processing. FIG. 11 is a graph showing temporal changes in the amount of carbon dioxide released when the supply amount is adjusted.

Hereinafter, one embodiment will be described with reference to the drawings. However, the following embodiments are examples for explaining the present disclosure, and are not intended to limit the present disclosure to the following contents. In the description, the same elements or elements having the same function are given the same reference numerals, and redundant description will be omitted. In addition, the positional relationships such as top, bottom, left, and right are based on the positional relationships shown in the drawings unless otherwise specified. Furthermore, the dimensional ratio of each element is not limited to the ratio shown in the drawings.

[Plant cultivation system]
FIG. 1 is a schematic diagram showing an example of a plant cultivation system including a gas supply device. A plant cultivation system 1 shown in FIG. 1 is a system for cultivating plants that perform photosynthesis. Plants are not limited as long as they photosynthesize, and may be agricultural crops such as vegetables and grains, flowers, algae, and plants. The plant cultivation system 1 includes a cultivation section 10 and a gas supply device 20.

In the cultivation section 10, plants are cultivated. The cultivation section 10 has a housing section 12 that forms an internal space for cultivating plants. The housing section 12 is, for example, a vinyl house. During the daytime (for example, from sunrise to sunset), sunlight enters the vinyl house and photosynthesis occurs in plants. At night (for example, from sunset to sunrise the next day), no sunlight enters the greenhouse, and plants do not photosynthesize.

Carbon dioxide is required for photosynthesis in plants, and the amount of carbon dioxide required increases as the amount of sunlight increases. The cultivation section 10 includes a gas introduction section 14 that introduces gas into the storage section 12 (internal space), and a gas discharge section 16 that releases (discharges) gas from inside the storage section 12 (internal space) to the outside of the storage section 12. and has.

(Gas supply device)
The gas supply device 20 supplies gas containing carbon dioxide toward the cultivation section 10 . By supplying carbon dioxide from the gas supply device 20 to the internal space of the cultivation section 10, the growth of plants within the cultivation section 10 is promoted. The gas supply device 20 stores carbon dioxide at night when plants are not photosynthesizing, and supplies the carbon dioxide stored at night to the cultivation unit 10 during the day when plants are photosynthesizing. The gas supply device 20 includes, for example, a supply section 30, a generation section 40, and a control section 100. Note that some elements included in the gas supply device 20 or the entire gas supply device 20 may be arranged within the cultivation section 10 (accommodating section 12).

The supply section 30 stores carbon dioxide and supplies gas containing the stored carbon dioxide toward the cultivation section 10 . The supply section 30 includes a material 32, a storage section 34, and gas introduction/output sections 36 and 38. The material 32 may adsorb and release carbon dioxide. Examples of the material 32 that adsorbs and releases carbon dioxide include activated carbon and silica gel. Alternatively, material 32 may absorb and release carbon dioxide. Various materials that can reversibly absorb and release carbon dioxide may be used as the material 32.

Components included in the material 32 that absorbs and releases carbon dioxide include polymer gels, polymer gel microparticles, aggregates of polymer gel microparticles, porous polymer gels, anion exchange resins, and the like. The polymer gel, polymer gel microparticles, aggregate of polymer gel microparticles, and porous polymer gel may be a polymer of monomers having amino groups. Examples of monomers include N-(aminoalkyl)acrylamide. The anion exchange resin may be a weakly basic anion exchange resin having a tertiary amine as an exchange group.

Specifically, Mitsubishi Chemical Corporation's acrylic WA10, styrene WA20 series, styrene WA30, etc. (all product names), as well as Muromachi Chemical Corporation's WMT-7624LG, DOWEX 66, and Marathon WBA. (both are trade names) can be used. The material 32 may contain moisture from the viewpoint of maintaining performance. The water content in the material 32 may be, for example, from 1 to 95% by weight.

The accommodating portion 34 accommodates the material 32. The accommodating portion 34 may accommodate a plurality of materials 32. The plurality of materials 32 may be held in respective cartridges within the housing portion 34 . The gas inlet/outlet parts 36 and 38 introduce gas into the housing part 34 or discharge gas from inside the housing part 34 to the outside. For example, when gas is introduced into the accommodating part 34 from the gas lead-in/out part 36, the gas is released from the gas lead-in/out part 38. When gas is introduced into the housing part 34 from the gas introduction/exit part 38, the gas is released from the gas introduction/exit part 36.

The gas introduced from either one of the gas inlet/outlet portions 36, 38 is guided to the material 32 within the housing portion 34. The gas released by the material 32 is released to the outside of the housing section 34 through either the gas inlet/outlet section 36 or 38. The gas lead-in/out section 36 and the gas introduction section 14 of the cultivation section 10 are connected via a flow path 52. Thereby, gas released from the storage section 34 (material 32) via the gas lead-in/out section 36 can be supplied to the cultivation section 10 through the channel 52.

The generation unit 40 supplies combustion gas containing carbon dioxide to the supply unit 30. The generation section 40 includes, for example, a heating section 42, a gas introduction section 44, and a gas discharge section 46. The heating unit 42 is configured to generate heat from an introduced gas such as air introduced through the gas introduction unit 44 by burning fossil fuel such as LPG (liquefied petroleum gas), LNG (liquefied natural gas), heavy oil, or kerosene. Produces combustion gas containing carbon dioxide. The gas discharge section 46 of the generation section 40 and the gas introduction/output section 36 of the supply section 30 are connected via a flow path 54. More specifically, the flow path 54 merges with the flow path 52 and is connected to the gas introduction/output section 36 . Thereby, gas (combustion gas containing carbon dioxide) released from the heating unit 42 via the gas release unit 46 can be supplied to the supply unit 30 through the flow path 54. Note that the gas discharge section 46 may be a chimney that discharges the gas from the heating section 42 to the outside. A flow path 54 may be connected as a branch path to the flow path located upstream within the chimney, and a portion of the gas flowing within the chimney may flow into the flow path 54.

A connection point 54c to which another flow path is connected is provided in the middle of the flow path 54. A flow path 62 extending to the gas discharge section 16 of the cultivation section 10 is connected to the connection point 54c. That is, the connection point 54c and the gas discharge section 16 are connected via the flow path 62. In the middle of the flow path 54, a connection point 54d different from the connection point 54c is provided. A flow path 56 extending to the gas introduction/output section 38 of the supply section 30 is connected to the connection point 54d. In other words, the connection point 54d and the gas introduction/output section 38 are connected via the flow path 56. With the above configuration, the gas released from the storage section 12 can be circulated to the supply section 30 through the channel 62, a part of the channel 54, and the channel 56. Note that, for convenience, the flow paths defined by the connection points 54c and 54d as boundaries in the flow path 54 are hereinafter referred to as a flow path 72, a flow path 74, and a flow path 76 in the order of proximity to the generation unit 40.

A flow path 64 for taking in outside air is connected in the middle of the flow path 62 . Thereby, outside air (air, etc.) can be supplied to the supply unit 30 through the flow path 64, a part of the flow path 62, and the flow paths 74 and 56. An exhaust flow path 58 for discharging gas to the outside is connected to the middle of the flow path 56 . Thereby, the gas discharged from the gas introduction/output section 38 can be discharged to the outside via the flow path 58. The flow path 74 is provided with a pump 78 (for example, an air pump) that draws gas from the flow path 62 or the flow path 72 and sends the gas toward the gas lead-in/out section 36 or the gas lead-in/out section 38 .

Although not shown, a heat exchanger may be provided on the flow path 54 or between the gas discharge section 46 and the flow path 54 to cool the gas sent to the supply section 30. When generating combustion gas using heavy oil in the generation section 40, impurities (for example, sulfur oxides, etc.) contained in the combustion gas are removed on the flow path 54 or between the gas discharge section 46 and the flow path 54. A device may be provided to do so. At least one device (such as a wet desulfurization tank or a humidifier) is provided on the flow path 54 or between the gas discharge section 46 and the flow path 54 to bring the gas sent into the supply section 30 into contact with water. Good too. The at least one device may contact the gas with water for at least one of cooling the gas to the supply 30, removing impurities in the gas, and adjusting the humidity of the gas. Further, moisture condensation may occur from gas humidified by a device that brings gas and water into contact, or mist may be generated from humidified gas. Therefore, a water trap may be provided in the flow path between the pump 78 and the supply section 30 to remove excess water.

(Operating status of gas supply device)
The plant cultivation system 1 further includes valves V1 to V7 for switching the operating state (mode) of the gas supply device 20. Valve V1 is provided in flow path 64. The valve V2 is provided in the flow path 72 of the flow paths 54. The valve V3 is provided in the flow path 62 (the flow path between the connection point with the flow path 64 of the flow path 62 and the gas discharge part 16). Valve V4 is provided in flow path 58. Valve V5 is provided in flow path 56.

The valve V6 is provided in the flow path 76 of the flow paths 54. The valve V7 is provided in the flow path 52 (the flow path between the confluence with the flow path 74 in the flow path 52 and the gas introduction section 14 of the cultivation section 10). The valves V1 to V7 open and close the flow paths by respectively switching to an open state or a closed state according to a control signal.

The operating state of the gas supply device 20 may include an absorption mode, a first discharge mode, a second discharge mode, and a fully closed mode. For example, the operating state of the gas supply device 20 is set to absorption mode at night when plants do not perform photosynthesis. During the daytime when plants perform photosynthesis, the operating state of the gas supply device 20 is set to one of the first emission mode, second emission mode, and fully closed mode. The operating state of the gas supply device 20 may be switched by switching the open/close states of the valves V1 to V7 according to control signals from the control unit 100, respectively. Examples of each mode will be described below with reference to FIGS. 2 to 4. In FIGS. 2 to 4, valves indicated by white circles are in the open state, and valves indicated by black circles are in the closed state.

FIG. 2 is a schematic diagram showing an example of an operating state in absorption mode. Absorption mode is a mode in which material 32 absorbs carbon dioxide. As shown in FIG. 2, in the absorption mode, valves V1, V3, V5, and V7 are closed, and valves V2, V4, and V6 are open. In the absorption mode, in the heating section 42, for example, fuel containing hydrocarbons supplied from a burner (not shown) is burned in the air, and gas containing carbon dioxide is generated. The concentration of carbon dioxide in the gas generated in the heating section 42 may be, for example, 1% by volume or more, 2 to 30% by volume, or 5 to 20% by volume under standard conditions (0° C., 1 atm). It may be expressed in volume %.

The gas (combustion gas containing carbon dioxide) generated in the heating section 42 flows toward the gas introduction/output section 36 through a channel 54 (channels 72, 74, 76) connected to the gas discharge section 46. After carbon dioxide has been absorbed by the material 32, the gas is discharged to the outside via the gas introduction/output section 38 and the flow path 58. A pump 78 provided in the flow path 74 may be used to efficiently introduce gas containing carbon dioxide into the gas introduction/output section 36. Alternatively, a fan, a compressor, or the like may be used instead of the pump 78. A filter that collects particulates such as soot contained in the combustion gas may be provided in the flow path 54 or the gas inlet/outlet portion 36 .

FIG. 3 is a schematic diagram showing an example of the operating state in the first discharge mode. The first release mode is a mode in which the material 32 releases carbon dioxide, and in order for the material 32 to release carbon dioxide, the gas circulated from the cultivation section 10 is sent to the supply section 30. As shown in FIG. 3, in the first discharge mode, valves V1, V2, V4, and V6 are closed, and valves V3, V5, and V7 are open. In the first discharge mode, combustion in the heating section 42 is stopped. The gas released from inside the storage section 12 of the cultivation section 10 is supplied from the gas introduction/output section 38 into the storage section 34 (material 32) through the flow path 62, the flow path 74, and the flow path 56.

In order to efficiently introduce gas into the gas introduction/output section 38, a pump 78 provided in the flow path 74 may be used. Alternatively, a fan, a compressor, or the like may be used instead of the pump 78. The gas released from the storage section 12 has a low concentration of carbon dioxide because photosynthesis is performed by plants. By supplying gas with a low concentration of carbon dioxide to the material 32, carbon dioxide is released from the material 32. As a result, gas containing carbon dioxide at a concentration higher than the carbon dioxide concentration of the gas released from the storage section 12 is supplied from the supply section 30 (gas introduction/output section 36) to the cultivation section 10 through the flow path 52. Ru.

FIG. 4 is a schematic diagram showing an example of the operating state in the second release mode. The second release mode is a mode in which the material 32 releases carbon dioxide, and air is introduced from the outside in order for the material 32 to release carbon dioxide. That is, in order to release carbon dioxide from the material 32, gas circulated from the cultivation section 10 is used in the first release mode, whereas air from the outside is used in the second release mode. In the second release mode, the concentration of carbon dioxide in the air introduced from the outside is, for example, less than 1% by volume.

In the second discharge mode, valves V2, V3, V4, and V6 are closed, and valves V1, V5, and V7 are open. The second release mode is similar to the first release mode except that the gas utilized by the material 32 to release carbon dioxide is air, so a detailed description of the second release mode will be omitted. The control unit 100 controls the control unit 100 so that more carbon dioxide is supplied to the material 32 while the material 32 is releasing gas containing carbon dioxide according to the concentration of carbon dioxide in the gas introduced into the gas introduction/output unit 38. The operating state of the gas supply device 20 may be switched to the first release mode or the second release mode.

In a fully closed mode (not shown), which is one of the operating states of the gas supply device 20, all valves V1 to V7 are in a closed state. In the fully closed mode, no gas is supplied to the material 32 and no gas is released from the material 32. While the operating state of the gas supply device 20 is in the fully closed mode, gas containing carbon dioxide is not supplied from the gas supply device 20 toward the cultivation section 10 . Details of switching the operating state of the gas supply device 20 during the day (first, second discharge mode, and fully closed mode) will be described later.

(control unit)
Returning to FIG. 1, the control unit 100 is a computer configured to control the supply unit 30, the generation unit 40, and the valves V1 to V7. The control unit 100 adjusts the amount of gas supplied from the gas supply device 20 to the cultivation unit 10. The control unit 100 adjusts the amount of gas supplied based on time during a period (hereinafter referred to as a “supply period”) during which gas is supplied to the cultivation unit 10 on a daily basis. For example, during the supply period, the control unit 100 controls the opening and closing states of the valves V1 to V7 to switch the operating state of the gas supply device 20 according to the current time or the elapsed time from the start time of the supply period. , adjust the amount of gas supplied to the cultivation section 10.

Here, with reference to FIG. 5, the reason why it is necessary to adjust the gas supply amount will be explained. FIG. 5 is a graph showing changes over time in the amount of carbon dioxide released in a comparative example in which the supply amount is not adjusted. FIG. 5 shows a case where the operating state of the gas supply device 20 is set to the first discharge mode during the entire supply period in which the start time of the supply period is 7:00 a.m. and the end time of the supply period is 5:00 p.m. The time changes in the amount of carbon dioxide released per unit time and the cumulative amount of released carbon dioxide are shown. The unit time is set to 10 minutes. Note that the amount of carbon dioxide released per unit time correlates with the concentration of carbon dioxide in the gas introduction/output section 36 of the supply section 30.

In FIG. 5, the time change in the amount of carbon dioxide released per unit time (hereinafter simply referred to as "the amount released per unit time") is shown by a broken line. The time change in the cumulative amount of carbon dioxide released is shown by a solid line, and the amount of carbon dioxide released per unit weight of the material 32 [mL/g] is shown. Note that the amount of carbon dioxide released may substantially match the amount of carbon dioxide supplied from the gas supply device 20 to the cultivation section 10. Under the measurement conditions when the measurement results in FIG. 5 were obtained, the gas supply device 20 was operated in absorption mode before the start time (7:00 a.m.), and the carbon dioxide was absorbed by the material 32 at the start time. The amount is 39.4 mL/g.

As shown in FIG. 5, when the gas supply device 20 is operated in the first release mode during the entire supply period, a large amount of carbon dioxide is released in the initial stage of release due to the characteristics of the material 32. Specifically, the release amount per unit time reaches its peak immediately after the start time. After the start time, the amount released per unit time decreases exponentially (like a quadratic curve). Generally, the relaxation time (time constant) during the exponential decrease depends on the temperature around the material 32, and the higher the temperature, the shorter the amount of release decreases. Further, the relaxation time differs depending on the type of material 32 and the method of filling carbon dioxide into the material 32.

On the other hand, the plants cultivated in the cultivation section 10 require more carbon dioxide at the time when the altitude of the sun rises than immediately after the start time (just after sunrise). For example, if the time when the maximum amount of carbon dioxide absorbed by plants is 10 am, in the example shown in Figure 5, the amount released per unit time is about 1/7 of the maximum value at 10 am. It is declining. Furthermore, the cumulative amount of carbon dioxide released at 10:00 a.m. has reached about 4/5 of the cumulative amount of carbon dioxide released at the end time. That is, the cumulative amount of carbon dioxide released Sr1 after 10 am during the supply period is about 1/4 of the cumulative amount of carbon dioxide released Sr2 before 10 am. This means that there is a risk that carbon dioxide will be supplied in excess before 10 a.m., when carbon dioxide is most needed, and that there will be a shortage of carbon dioxide around 10 a.m.

From the above, the control unit 100 determines, on a daily basis, after the time (hereinafter referred to as "intermediate time ti") when the predicted value of the amount of carbon dioxide absorbed by the plants in the cultivation unit 10 becomes the maximum during the supply period. The amount of gas supplied is adjusted so that the cumulative amount of carbon dioxide released (cumulative supply amount) of the period of time and the cumulative amount of carbon dioxide released (cumulative amount of supply) up to the intermediate time ti in the supply period have a predetermined relationship. do. The intermediate time ti is set according to the type of plant cultivated in the cultivation section 10 and the cultivation environment of the plant, and is a predicted time at which the amount of carbon dioxide absorbed becomes maximum.

The intermediate time ti may be arbitrarily set by an operator (for example, a provider of the gas supply device 20 or a plant producer). The intermediate time ti may be stored in advance in the control unit 100 by the operator, or may be set based on input information from the operator. The intermediate time ti may be maintained at a value once set. Alternatively, the intermediate time ti may be set daily, monthly, seasonal, or yearly.

The intermediate time ti may be set to the central time of each day, or may be set according to the central time of the day. As an example, the intermediate time ti may be 2 to 7 hours after sunrise, 2.5 to 6 hours after sunrise, or 3 to 5 hours after sunrise. For example, the intermediate time ti may be from 9:00 am to 2:00 pm, may be from 9:30 am to 1:30 pm, or may be from 10:00 am to 1:00 pm.

In order to set the intermediate time ti at which the predicted value of the amount of carbon dioxide absorbed is the maximum, predicted weather information regarding the location where the cultivation section 10 is installed may be used. The weather forecast information may include a predicted value of the temperature at the location or a predicted change in the amount of sunlight over time. Alternatively, if various sensors such as a solar photometer, thermometer, carbon dioxide concentration meter, or rainfall sensor are provided, data detected by the various sensors may be used to set the intermediate time ti. .

FIG. 6 is a graph showing temporal changes in the gas supply amount when the supply amount is adjusted. Similarly to FIG. 5, in FIG. 6, the amount of carbon dioxide released per unit time is shown by a broken line, and the cumulative amount of carbon dioxide released is shown by a solid line. Note that the unit time is set to 10 minutes. The control unit 100 determines, on a daily basis, that the cumulative release amount Sc1 (cumulative supply amount) of carbon dioxide after intermediate time ti is the cumulative release amount Sc2 (cumulative supply amount) of carbon dioxide up to intermediate time ti during the supply period. Adjust the gas supply amount so that it is 1/3 to 3 times the amount. The cumulative release amount Sc1 is the cumulative release amount of carbon dioxide from the intermediate time ti to the end time, and the cumulative release amount Sc2 is the cumulative release amount of carbon dioxide from the start time to the intermediate time ti.

From the perspective of suppressing the imbalance in the supply amount of carbon dioxide before the intermediate time ti, the control unit 100 sets the cumulative release amount Sc1 to 1/3 or more, 1/2 or more of the cumulative release amount Sc2, or 2 The gas supply amount may be controlled to be 3 times or more. From the viewpoint of suppressing the imbalance in the gas supply amount after the intermediate time ti, the control unit 100 sets the cumulative release amount Sc1 to 3 times or less, 2.5 times or less, or 2 times or less of the cumulative release amount Sc2. The amount of gas supplied may be adjusted as follows.

The control unit 100 may adjust the amount of gas supplied so that gas containing 70% or more of carbon dioxide stored in the material 32 is supplied to the cultivation unit 10 during the supply period on a daily basis. . Specifically, the control unit 100 directs gas containing carbon dioxide that is 70% or more of the amount stored in the material 32 in the absorption mode during the night immediately before the supply period to the cultivation unit 10 during the entire supply period. The amount of gas supplied may be adjusted so as to supply the same amount of gas. From the viewpoint of more efficient supply of carbon dioxide, the amount of carbon dioxide supplied daily may be 80% or more of the amount stored by the material 32, or may be 90% or more.

Next, details of the control unit 100 will be further explained with reference to FIGS. 7 and 8. FIG. 7 is a block diagram showing an example of the functional configuration of the control section. As shown in FIG. 7, the control unit 100 has a functional configuration including, for example, a reading unit 102, a storage unit 104, a date and time information acquisition unit 106, a period calculation unit 108, a condition calculation unit 110, A switching instruction section 112 is provided. The processing executed by each functional module corresponds to the processing executed by the control unit 100.

These functional modules merely divide the functions of the control section 100 into a plurality of modules for convenience, and do not necessarily mean that the hardware that constitutes the control section 100 is divided into such modules. Each functional module is not limited to being realized by executing a program, but may be realized by a dedicated electric circuit (for example, a logic circuit) or an integrated circuit (ASIC: application specific integrated circuit) that integrates the same. You can.

The reading unit 102 is configured to read a program from a computer-readable storage medium RM. The storage medium RM records a program for performing a gas supply method (adjustment of gas supply amount) executed in the gas supply device 20. The storage medium RM may be, for example, a semiconductor memory, an optical recording disk, a magnetic recording disk, or a magneto-optical recording disk.

The storage unit 104 is configured to store various data. The storage unit 104 stores, for example, the program read from the storage medium RM by the reading unit 102, position information where the cultivation unit 10 is installed, and intermediate time ti. As the location information, for example, the latitude and longitude where the cultivation section is located, or the address (city, town, village and prefecture) are stored.

The date and time information acquisition unit 106 is configured to acquire information indicating the date (year, month, day) and current time (hereinafter referred to as "date and time information") for each day. The date and time information acquisition unit 106 may acquire the date and time information from outside the control unit 100, or may acquire the date and time information from a clock (timekeeping function) that the control unit 100 itself has internally.

The period calculation unit 108 is configured to calculate the supply period during which gas containing carbon dioxide is supplied from the supply unit 30 to the cultivation unit 10 on a daily basis. The period calculation unit 108 calculates the start time and end time of the supply period, for example, on a daily basis. The period calculation unit 108 may calculate the start time and end time of the supply period on a daily basis based on the position information of the cultivation unit 10. The period calculation unit 108 predicts the sunrise time and sunset time for each day based on the longitude and latitude where the cultivation unit 10 is located, calculates the predicted sunrise time as the start time, and calculates the predicted sunset time as the start time. It may also be calculated as the end time.

To specifically explain a calculation example of the period calculation unit 108, the period calculation unit 108 calculates the supply period using functions for calculating the predicted values of sunrise time and sunset time for each day. good. The sunrise time t1 and the sunset time t2 can be expressed as a periodic function with a period of one year, as shown in the following equation (1). Here, pi in equation (1) indicates the angle per day shown in equation (2). a ₀ and a _n are coefficients, a ₀ indicates the average sunrise time (average sunset time), and a ₁ to a ₄ indicate the time amplitude. b _n is a coefficient, and b ₁ to b ₄ indicate phases. d is a variable and indicates the number of days from an arbitrarily set reference date.

The nine coefficients included in equation (1) are calculated in advance. For example, for each of multiple cities (points) with different latitudes and longitudes, equation (1) is fitted to the data based on known sunset/sunrise time data, which are past actual values or future predicted values. Each coefficient is calculated as follows. Each variable obtained for each of multiple cities is replaced with the value at a point at 135° east longitude, and then each variable is calculated as a function of latitude α using the cubic approximation formula shown in equation (3). approximated.

The period calculation unit 108 uses the functions shown by the above formulas (1) to (3) to calculate the location information (longitude and latitude) of the cultivation unit 10 and the information indicating the date acquired by the date and time information acquisition unit 106. Accordingly, the sunrise time and sunset time may be calculated. In addition, the period calculation part 108 may calculate a supply period by acquiring the sunrise time and sunset time according to the positional information of the cultivation part 10 from the outside (for example, the Internet etc.).

The condition calculation unit 110 is configured to calculate conditions for adjusting the amount of gas supplied to the cultivation unit 10 (hereinafter referred to as “adjustment conditions”). For example, the condition calculation unit 110 calculates, as an adjustment condition, the operating state of the gas supply device 20 according to the time (elapsed time) of the supply period.

The switching instruction unit 112 is configured to switch the operating state of the gas supply device 20 according to the adjustment conditions calculated by the condition calculation unit 110. For example, the switching instruction unit 112 controls the operating state of the gas supply device 20 by switching the open/close states of the valves V1 to V7 according to the conditions calculated by the condition calculation unit 110 according to the time (elapsed time) of the supply period. Switch.

As described above, the switching instruction section 112 switches the operating state of the gas supply device 20 according to the adjustment conditions calculated by the condition calculation section 110, so that the control section 100 adjusts the gas supply amount based on the time. To explain an example of calculating the adjustment conditions, the condition calculation unit 110 calculates, for each day, that the cumulative release amount Sc1 (cumulative supply amount) of carbon dioxide after the intermediate time ti is the same as the cumulative amount of carbon dioxide released before the intermediate time ti during the supply period. Adjustment conditions are calculated so that the cumulative carbon dioxide release amount Sc2 (cumulative supply amount) is 1/3 to 3 times. The condition calculation unit 110 may calculate adjustment conditions such that gas containing carbon dioxide that is 70% or more of the amount stored by the material 32 is supplied to the cultivation unit 10 during the supply period on a daily basis.

More specifically, the condition calculation unit 110 determines the time period during which the gas supply is continued and the time period during which the gas supply is stopped in each of the plurality of divided periods obtained by dividing the supply period calculated by the period calculation unit 108 in chronological order. may also be calculated. The time during which gas supply is continued (hereinafter referred to as "supply continuation time To") is the time during which the operating state of the gas supply device 20 is maintained in the first discharge mode or the second discharge mode. The time during which the gas supply is stopped (hereinafter referred to as "supply stop time Ts") is the time during which the operating state of the gas supply device 20 is maintained in the fully closed mode. The condition calculation unit 110 calculates the supply continuation time To and the supply stop time Ts for each of the plurality of divided periods so as to change the ratio of the supply continuation time To and the supply stop time Ts for each divided period according to the time. do.

The condition calculation unit 110 may calculate the supply continuation time To and the supply stop time Ts for each of the plurality of divided periods so that the proportion of the supply continuation time To in the divided period increases as time passes. . As an example, when the intermediate time ti is set to 10:00 a.m., the condition calculation unit 110 sets the divided period to 10 minutes (600 seconds) and calculates the divided period using the function expressed by the following formula (4). The supply continuation time To (seconds) for each time may be calculated.

In equation (4), tn is the elapsed time (minutes) from the start time, (t2-t1) is the daytime time (hours) obtained by subtracting the sunrise time from the sunset time, and int( tn) indicates a function that converts a real number to an integer. The condition calculation unit 110 may use the start time of each divided period as the elapsed time (minutes). Note that when the set value of the intermediate time ti is different, the coefficient (constant) included in equation (4) may be adjusted according to the set value.

The condition calculation unit 110 may directly use the value obtained using equation (4) as the supply continuation time To (seconds), or may perform correction according to the obtained value. For example, the condition calculation unit 110 may set the supply continuation time To to 60 seconds when the value obtained by equation (4) is less than 60. When the value obtained by equation (4) is greater than or equal to 60 and less than 540, the condition calculation unit 110 may directly use the obtained value as the supply continuation time To.

The condition calculation unit 110 may set the supply continuation time To to 540 seconds when the value obtained by equation (4) is 540 or more and less than 600. The condition calculation unit 110 may set the supply continuation time To to 600 seconds when the value obtained by equation (4) is greater than 600. Note that the supply stop time Ts may be calculated by subtracting the supply continuation time To obtained using equation (4) from 600 seconds for each divided period.

Note that the measurement results shown in FIG. 6 are results obtained by switching the operating state according to the conditions calculated by the above equation (4). Although the intermediate time ti is set at 10 a.m., the emission characteristics from the material 32 change depending on the surrounding environment (temperature, humidity, weather, etc.) during use, so it is not always possible to It does not necessarily mean that the amount of carbon dioxide released will be the highest. However, compared to the change in the amount of release per unit time in the measurement results shown in FIG. Recognize. Note that the storage unit 104 of the control unit 100 may store the release curve (release characteristics) of the material 32 shown by the broken line in FIG. The storage unit 104 may obtain and store representative release curves for different temperatures in advance. The condition calculation unit 110 may acquire temperature measurement results, or may calculate predicted temperatures from weather forecasts and illuminance measurements. The condition calculation unit 110 may calculate the adjustment conditions so that the temporal change in the amount of carbon dioxide released approaches the target, taking into account the release characteristics of the material 32 according to the measured value or predicted value of temperature.

FIG. 8 is a block diagram showing an example of the hardware configuration of the control section. As shown in FIG. 8, the control unit 100 includes a circuit 120 as a hardware configuration. Circuit 120 may be comprised of electrical circuitry. Specifically, the circuit 120 includes a processor 122, a memory 124 (storage unit), a storage 126 (storage unit), a timer 128, and an input/output port 132.

The processor 122 executes programs in cooperation with at least one of the memory 124 and the storage 126, and inputs and outputs signals via the input/output port 132, thereby configuring each of the functional modules described above. The timer 128 measures elapsed time, for example, by counting reference pulses of a constant period. The input/output port 132 inputs and outputs electrical signals to and from the valves V1 to V7.

[How to adjust gas supply amount]
Next, with reference to FIGS. 9 and 10, a method of adjusting the gas supply amount executed by the control unit 100 will be described as an example of the gas supply method. FIG. 9 is a flowchart illustrating an example of a method for adjusting the daily gas supply amount.

In a state where the operating state of the gas supply device 20 is set to an absorption mode in which carbon dioxide is absorbed into the material 32, the control unit 100 first executes step S01. In step S01, for example, the period calculation unit 108 calculates the period from the gas supply device 20 to the cultivation unit 10 based on the information indicating the date obtained by the date and time information acquisition unit 106 and the position information of the cultivation unit 10 stored in the storage unit 104. Calculate the supply period for supplying gas to. The period calculating unit 108 may calculate the sunrise time and the sunset time based on the relevant date for each day and the position information of the cultivation unit 10, and may set the calculated sunrise time as the start time. The sunset time may be set as the end time.

Next, the control unit 100 executes step S02. In step S02, for example, the switching instruction unit 112 waits until the start time of the supply period. The switching instruction unit 112 may wait until the current time acquired by the date and time information acquisition unit 106 reaches the start time (for example, the predicted sunrise time). Thereby, the operating state of the gas supply device 20 is maintained in the absorption mode until the start time of the supply period.

In step S02, when the start time of the supply period is reached, the control unit 100 executes step S03. In step S03, for example, the control unit 100 executes a gas supply process of adjusting the supply amount for each divided period included in a plurality of divided periods obtained by dividing the supply period in time order. Details of the gas supply process in step S03 will be described later.

Next, the control unit 100 executes step S04. In step S04, for example, the switching instruction unit 112 waits until the end time of the supply period. The switching instruction unit 112 may wait until the current time acquired by the date and time information acquisition unit 106 or the elapsed time from the start time reaches the end time (predicted sunset time).

In step S04, when the end time of the supply period is reached, the control unit 100 executes step S05. In step S05, for example, the switching instruction unit 112 controls the valves V1 to V7 and the generation unit 40 (heating unit 42) to change the operating state of the gas supply device 20 to the mode set at the end of step S03. , switch to absorption mode. As a result, carbon dioxide is absorbed (adsorbed) into the material 32 again during the night after the end of the supply period. With the above, the series of processes of the gas supply method for one day is completed. The control unit 100 similarly repeats steps S01 to S05 on the next day and thereafter.

FIG. 10 is a flowchart showing an example of the gas supply process in step S03. The control unit 100 first executes step S11. In step S11, for example, the switching instruction unit 112 switches the operating state of the gas supply device 20 to the first discharge mode. In the first step S11, the switching instruction unit 112 switches the operating state of the gas supply device 20 from the absorption mode to the first discharge mode by controlling the valves V1 to V7. Thereby, supply of gas (carbon dioxide) to the cultivation section 10 during the supply period is started.

Next, the control unit 100 executes step S12. In step S12, for example, the condition calculation unit 110 calculates the adjustment conditions (operating state of the gas supply device 20) of the divided period including the current time. The condition calculation unit 110 may calculate the supply continuation time To and the supply stop time Ts in the divided period using the above-mentioned equation (4) using the current time (elapsed time tn) as a variable.

Next, the control unit 100 executes step S13. In step S13, for example, the switching instruction unit 112 determines whether the divided period including the current time includes a fully closed mode period in which the valves V1 to V7 are closed. As an example, the switching instruction unit 112 determines whether the supply stop time Ts calculated using the above equation (4) is greater than zero.

If it is determined in step S13 that the divided period includes the fully closed mode (step S13: YES), the control unit 100 executes step S14. In step S14, for example, the switching instruction unit 112 waits until the supply continuation time To has elapsed from the start time of the divided period. In step S12, when the supply continuation time To has elapsed, the control unit 100 executes step S15. In step S15, for example, the switching instruction unit 112 switches the operating state of the gas supply device 20 from the first discharge mode to the fully closed mode by controlling the valves V1 to V7.

On the other hand, if it is determined in step S13 that the fully closed mode is not included in the adjustment conditions for the divided period (step S13: NO), the control unit 100 does not execute steps S14 and S15. That is, the switching instruction unit 112 maintains the operating state of the gas supply device 20 in the first discharge mode.

Next, the control unit 100 executes step S16. In step S16, for example, the control unit 100 waits until the division period ends. As described above, when the divided period includes the fully closed mode, the gas containing carbon dioxide is supplied to the cultivation section 10 during the supply continuation time To of the divided period, and the gas containing carbon dioxide is supplied to the cultivation section 10 during the supply stop time Ts. Carbon-containing gas is not supplied. On the other hand, if the divided period does not include the fully closed mode, gas containing carbon dioxide is supplied to the cultivation section 10 during the entire divided period.

Next, the control unit 100 executes step S17. In step S17, the control unit 100 determines whether the end time is included in the next divided period. The control unit 100 determines that the scheduled end time of the next divided period starting from the current time after execution of step S16 (the time obtained by adding the time of one divided period to the current time) is later than the end time of the supply period. You can decide whether or not.

If it is determined in step S17 that the end time is not included in the next divided period (step S17: NO), the control unit 100 repeats the processes of steps S11 to S17. In step S01 from the second time onward, if the fully closed mode was included in the previous divided period, the switching instruction unit 112 changes the operating state of the gas supply device 20 from the fully closed mode to the first discharge mode. Switch. If the fully closed mode was not included in the previous divided period, the switching instruction unit 112 maintains the operating state of the gas supply device 20 in the first discharge mode.

On the other hand, if it is determined in step S17 that the end time is included in the next divided period (step S17: YES), the control unit 100 ends the gas supply process in step S03. Note that the series of processes of the gas supply method and the series of processes of the gas supply process illustrated above are merely examples, and can be changed as appropriate. In order to supply gas to the cultivation unit 10, the control unit 100 may set the operating state of the gas supply device 20 to the second discharge mode instead of the first discharge mode during all or part of the supply period. .

The control unit 100 may perform one step and another step in parallel, or may perform the steps in a different order. For example, the control unit 100 may execute the process of step S12 in parallel with the process of switching to the first release mode (second release mode) of step S11. Instead of step S12, the control unit 100 may calculate adjustment conditions for each of a plurality of divided periods (all divided periods) before executing the gas supply process in step S03.

[Effects of embodiment]
In the gas supply device 20 and gas supply method described above, the cumulative supply amount of carbon dioxide (cumulative release amount Sc1) after the intermediate time ti when the amount of carbon dioxide absorbed by plants during the supply period peaks on a daily basis. is 1/3 to 3 times the cumulative supply amount of carbon dioxide (cumulative release amount Sc2) up to the intermediate time ti during the supply period, and the gas containing carbon dioxide is supplied toward the cultivation section 10. The amount of supply is adjusted based on the time of day. Therefore, the amount of carbon dioxide released per unit time from the material 32 can be made larger before and after the intermediate time when the predicted value of the amount of carbon dioxide absorbed is the maximum, than at other times. Therefore, it becomes possible to efficiently supply gas containing carbon dioxide.

In the above embodiment, the amount of gas supplied is adjusted so that gas containing 70% or more of carbon dioxide of the amount stored by the material 32 is supplied toward the cultivation section 10 during the supply period on a daily basis. . In this case, the amount of gas containing carbon dioxide supplied during the entire supply period can be maintained at a certain value or higher. Therefore, the deviation in the amount of carbon dioxide released per unit time can be brought closer to the intermediate time ti without reducing the total gas supply amount. Therefore, it becomes possible to supply gas containing carbon dioxide more efficiently.

In the embodiments described above, the amount of gas supplied can be adjusted by changing the ratio of the time during which the gas supply is continued and the time during which the gas supply is stopped in each of the plurality of divided periods obtained by dividing the supply period. adjusted. In this case, a device (for example, valves V1 to V7) that can be switched between two states: a state in which gas is supplied (for example, first discharge mode) and a state in which gas supply is stopped (for example, fully closed mode). ), the amount of gas supplied can be adjusted, making it possible to simplify the device configuration and reduce the processing load on the control unit 100.

In the above embodiment, the start time and end time of the supply period are set based on the position information of the cultivation section 10. In this case, gas can be supplied in an appropriate period according to the movement of the sun at the position of the cultivation section 10, so that gas containing carbon dioxide can be supplied more efficiently.

[Modified example]
Although one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment at all. In the above example, in one divided period, the gas supply device 20 operates in the first discharge mode (second discharge mode) in the first stage, and in the fully closed mode in the second stage, but in the first stage of the divided period, the gas supply device 20 operates in the fully closed mode. It may operate in the fully closed mode in the middle of the divided period. The mode in which the gas supply to the cultivation section 10 is stopped during the daytime may be other than the fully closed mode. For example, as the mode for stopping the supply of gas to the cultivation section 10, the gas supply device 20 may be operated so that at least the gas introduction/extraction at the gas introduction/extraction sections 36 and 38 is stopped.

The gas supply device 20 may have a configuration that can operate in the first release mode without including the second release mode as the mode for supplying gas to the cultivation unit 10 (the gas supply device 20 may be configured to operate in the first release mode without including the second release mode). ). The gas supply device 20 may have a configuration that can operate in a second release mode without including the first release mode as a mode for supplying gas to the cultivation section 10 (including a flow path for introducing external air). ).

The amount of gas supplied is adjusted by adjusting the opening time and closing time of the valve for each divided period. The amount of gas supplied may be adjusted based on the time by adjusting the opening degree of the opening. The control unit 100 may adjust the amount of gas supplied by changing the opening degree of the valve depending on the time (time elapsed from the start of the supply time). Instead of or in addition to the valve, the control unit 100 turns on and off a pump 78 for sending air or the like to be sent into the material 32 in order to release gas containing carbon dioxide from the material 32, or turns the pump 78 on and off. The amount of gas supplied may be adjusted based on time by switching the output value of .

Similar to FIG. 6, FIG. 11 is a graph showing changes over time in the amount of carbon dioxide released when the supply amount is adjusted. The condition calculation unit 110 may calculate the supply continuation time To (seconds) for each divided period using a function shown by the following equation (5) instead of the above-mentioned equation (4). Equation (5) is a function used when, for example, the intermediate time ti is set to 12:00 a.m. (midnight).

The measurement results shown in FIG. 11 are the results obtained by switching the operating state according to the conditions calculated by the above equation (5). In the measurement results shown in FIG. 11, similarly to the measurement results shown in FIG. 6, the cumulative release amount Sc1 of carbon dioxide after the intermediate time ti is 1/3 to 3 of the cumulative release amount Sc2 up to the intermediate time ti. It has doubled. Therefore, the time when the amount of carbon dioxide released per unit time is maximum is closer to (shifted) to the intermediate time ti than the start time.

The gas supply device 20 according to the above embodiment may be applied to the cultivation section 10 in which a concentration sensor for measuring the concentration of carbon dioxide is not installed. Even if the cultivation unit 10 does not have a concentration sensor, the gas supply device 20 can supply a large amount of carbon dioxide around the intermediate time ti when the amount of carbon dioxide absorbed by plants is predicted to be maximum. becomes. Existing plant cultivation equipment is generally not equipped with a concentration sensor, and the gas supply device 20 is applicable to existing plant cultivation equipment. Furthermore, by using the gas supply device 20 in the cultivation section 10 that does not have a concentration sensor, the entire plant cultivation system 1 can be simplified.

In the gas supply method exemplified above, the gas supply device 20 is set to the absorption mode at night, and the gas supply device 20 is set to the release mode during the day. mode may be set. For example, when the temperature falls below a certain value during the day, the control unit 100 switches the operating state of the gas supply device 20 from the emission mode to the absorption mode, and stops the generation of combustion gas by the heating unit 42 of the generation unit 40. You may start. Then, the control unit 100 may set the gas supply device 20 to absorption mode for a predetermined period of time to cause the material 32 to absorb carbon dioxide. The control unit 100 may switch the operating state of the gas supply device 20 from the absorption mode to the emission mode again after a predetermined period of time has elapsed.

According to the present disclosure, a gas supply device, a gas supply method, and a storage medium that can efficiently supply gas containing carbon dioxide are provided.

DESCRIPTION OF SYMBOLS 1... Plant cultivation system, 10... Cultivation part, 12... Accommodation part, 14... Gas introduction part, 16... Gas discharge part, 20... Gas supply device, 30... Supply part, 32... Material, 34... Accommodation part, 36, 38...Gas introduction/output section, 40...Generation section, 42...Heating section, 44...Gas introduction section, 46...Gas discharge section, 52, 54, 56, 58, 62, 64...Flow path, V1 to V7...Valve, 100 ...control section, 102...reading section, 104...storage section, 106...date and time information acquisition section, 108...period calculation section, 110...condition calculation section, 112...switch instruction section.

Claims (7)

a supply section that has a material that absorbs and releases carbon dioxide and supplies a gas containing carbon dioxide to a cultivation section where plants are cultivated;
a control unit that adjusts the amount of gas supplied based on time during the gas supply period defined by a start time and an end time ;
The water content in the material is 1 to 95% by mass,
The control unit is configured to determine, on a daily basis, that the cumulative supply amount of carbon dioxide from the intermediate time at which the predicted value of the amount of carbon dioxide absorbed by the plants during the supply period becomes maximum to the end time is determined within the supply period. A gas supply device that adjusts the supply amount of the gas to be 1/3 to 3 times the cumulative supply amount of carbon dioxide from the start time to the intermediate time. The control unit adjusts the supply amount of the gas so that the gas containing carbon dioxide that is 70% or more of the amount stored by the material is supplied to the cultivation unit during the supply period on a daily basis. , The gas supply device according to claim 1. a supply section that has a material that absorbs or adsorbs and releases carbon dioxide and supplies a gas containing carbon dioxide to a cultivation section where plants are cultivated;
a control unit that adjusts the amount of gas supplied based on time during the gas supply period defined by a start time and an end time;
The control unit is configured to determine, on a daily basis, that the cumulative supply amount of carbon dioxide from the intermediate time at which the predicted value of the amount of carbon dioxide absorbed by the plants during the supply period becomes maximum to the end time is determined within the supply period. Adjusting the supply amount of the gas so that it is 1/3 to 3 times the cumulative supply amount of carbon dioxide from the start time to the intermediate time,
The control unit controls the supply of the gas by changing the ratio of the time during which the supply of the gas is continued and the time during which the supply of the gas is stopped in each of a plurality of divided periods obtained by dividing the supply period. A gas supply device that adjusts the supply amount. The gas supply device according to any one of claims 1 to 3, wherein the control unit sets the start time and end time of the supply period based on position information of the cultivation unit. A gas supply method for supplying gas containing carbon dioxide to a cultivation area where plants are cultivated through a material that absorbs and releases carbon dioxide, the method comprising:
In the gas supply period defined by the start time and end time , the gas supply amount is adjusted based on the time,
The water content in the material is 1 to 95% by mass,
Adjusting the supply amount of the gas means that the cumulative supply amount of carbon dioxide is adjusted daily from the intermediate time at which the predicted value of the amount of carbon dioxide absorbed by the plants during the supply period to the end time is the maximum. , a gas supply method comprising adjusting the supply amount of the gas to be 1/3 to 3 times the cumulative supply amount of carbon dioxide from the start time to the intermediate time in the supply period. A gas supply method for supplying a gas containing carbon dioxide to a cultivation area where plants are cultivated through a material that absorbs or adsorbs and releases carbon dioxide, the method comprising:
In the gas supply period defined by the start time and end time, the gas supply amount is adjusted based on the time,
Adjusting the supply amount of the gas means that the cumulative supply amount of carbon dioxide is adjusted daily from the intermediate time at which the predicted value of the amount of carbon dioxide absorbed by the plants during the supply period to the end time is the maximum. , adjusting the supply amount of the gas so that it is 1/3 to 3 times the cumulative supply amount of carbon dioxide from the start time to the intermediate time in the supply period,
Adjusting the amount of gas supplied changes the ratio of the time during which the supply of the gas is continued and the time during which the supply of the gas is stopped in each of a plurality of divided periods obtained by dividing the supply period. gas supply method, including A computer-readable storage medium storing a program for causing an apparatus to execute the gas supply method according to claim 5 or 6 .

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