JP6259638B2 - Solar energy utilization system - Google Patents

Description

  The present invention relates to a technology of a solar energy utilization system that can generate power using sunlight and can use heat obtained by power generation.

  2. Description of the Related Art Conventionally, a technology of a solar energy utilization system (hybrid system) that can generate power using sunlight and can use heat obtained by power generation has been publicly known. For example, as described in Patent Document 1.

  In Patent Document 1, a solar power generation module (power generation unit) capable of generating power using sunlight, a solar heat collection module (heat collection unit) capable of collecting heat of the solar power generation module, and heat are stored. A heat storage tank, a drive pump (pump) that circulates a liquid heat medium (heat transfer medium) between the solar heat collection module and the heat storage tank, a temperature sensor that detects the temperature in the heat storage tank, A solar energy utilization system is described that includes a heat dissipation promoting means for promoting heat dissipation of a heat medium.

  In the solar energy utilization system described in Patent Literature 1, when the temperature in the heat storage tank becomes higher than the set value, the heat dissipation medium is urged to radiate heat. Thereby, an excessive temperature rise of the electric heating medium can be prevented, and a decrease in power generation efficiency or damage of the power generation unit can be prevented.

  However, Patent Document 1 does not mention control of a pump that carries heat (circulates a heat transfer medium) from the heat collecting section to the heat storage tank. For this reason, there is a concern that the pump is driven in a state where the temperature of the heat collecting unit (power generation unit) is not so high, and an operation with poor heat collecting efficiency is performed.

  In addition, in order to solve such problems, a large number of sensors (for example, a temperature sensor that detects the temperature of the power generation unit (heat collection unit)) is required to construct a system capable of highly efficient control. There are concerns about an increase in costs.

JP-A-11-37570

  The present invention has been made in view of the situation as described above, and the problem to be solved is a solar energy utilization system capable of efficient operation while preventing an increase in cost due to an increase in sensors. Is to provide.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

That is, in claim 1, a power generation unit capable of generating power using sunlight, a heat collection unit capable of collecting heat of the power generation unit, a heat storage tank capable of storing heat, and the heat collection unit A heat transfer medium that can circulate between the heat transfer tank and the heat storage tank, a pump that circulates the heat transfer medium, a power generation amount detecting means that detects a power generation amount in the power generation section , and a temperature in the heat storage tank And a heat storage tank temperature detecting means for calculating the integrated value of the power generation amount in the power generation unit, and when the integrated value exceeds a predetermined threshold, the pump is driven to store heat in the heat storage tank. The predetermined threshold is determined based on the temperature of the power generation unit estimated from the temperature in the heat storage tank after the pump is driven for a predetermined time when the power generation unit starts power generation. It is.

According to a second aspect of the present invention, the predetermined threshold value is determined so as to increase as the estimated temperature of the power generation unit decreases.

According to a third aspect of the present invention, the predetermined threshold value is updated so as to increase in accordance with an elapsed time from the start of power generation by the power generation unit.

In Claim 4 , the said predetermined threshold value is determined so that it may become so high that the temperature in the said thermal storage tank just before the said electric power generation part starts electric power generation is high.

  As effects of the present invention, the following effects can be obtained.

In claim 1, efficient operation is possible while preventing an increase in cost due to an increase in sensors. That is, since it controls using the electric power generation amount detection means and heat storage tank temperature detection means which are normally provided, it is not necessary to provide sensors separately. Also, based on the temperature of the power generation unit by estimating the temperature of the power generation unit based on the temperature in the heat storage tank after the heat transfer medium is carried from the heat collection unit to the heat storage tank, and determining a predetermined threshold value A threshold can be set.

In claim 2 , an appropriate threshold value can be determined. In other words, the lower the estimated temperature of the power generation unit, the longer the time taken to increase the temperature of the power generation unit by increasing the integrated value of the power generation amount until the pump is driven (that is, increasing the threshold). can do.

In the third aspect , the threshold value can be updated to an appropriate value. That is, even if the integrated value of the power generation amount is the same, the temperature of the power generation unit is less likely to increase as the solar radiation amount is lower. Therefore, when the amount of solar radiation is low (that is, when the increase in the integrated value of the power generation amount is slow), it is possible to secure a longer time for increasing the temperature of the power generation unit by increasing the threshold value. .

In claim 4 , an appropriate threshold value can be determined. That is, unless the temperature of the power generation unit is higher than the temperature in the heat storage tank to some extent, heat cannot be efficiently stored in the heat storage tank even if the heat transfer medium is circulated. Therefore, the time for raising the temperature of the power generation unit to an appropriate temperature can be ensured by increasing or decreasing the threshold according to the temperature in the heat storage tank.

The schematic diagram which showed the structure of the solar energy utilization system which concerns on one Embodiment of this invention. Similarly, the flowchart which showed the control aspect. (A) The figure which showed the relationship between temporary initial value and the temperature of the estimated electric power generation part. (B) The figure which showed the relationship between an addition value and the temperature in a thermal storage tank. The figure which showed the relationship between a threshold value and the elapsed time from a power generation start. (A) The figure which showed the mode of control in the day of fine weather. (B) The figure which showed the mode of control in the cloudy day. The figure which showed the mode of the control on a rainy day.

  Hereinafter, a solar energy utilization system (hereinafter simply referred to as “system”) 1 which is an embodiment of the solar energy utilization system according to the present invention will be described with reference to FIG.

  The system 1 is provided in a house or the like, and is for using electric power generated by using solar energy (sunlight or solar heat) or heat collected in the house. The system 1 mainly includes a power generation unit 10, a heat collection unit 20, a heat storage tank 30, a heat collection pump 40, a heat exchanger 50, a hot water pump 60, a hot water supply facility 70, and a main controller 100.

  The power generation unit 10 generates power using sunlight. The power generation unit 10 includes a solar cell panel formed in a substantially flat plate shape. The power generation unit 10 is installed in a sunny place such as on the roof of a house. The power generation unit 10 can generate an amount of electric power according to the amount of solar radiation, the state of the power generation unit 10 (for example, the temperature of the power generation unit 10), and the like.

  Moreover, the electric power generated in the power generation unit 10 is supplied to a load in the house. A power sensor 12 that detects the power (the amount of power generated by the power generation unit 10) is provided in the power distribution path. The power sensor 12 is an embodiment of the power generation amount detection means according to the present invention.

  The heat collection unit 20 collects heat from the power generation unit 10. The heat collection part 20 is comprised by the transparent porous chamber heat insulating material, selective absorption film, etc. which were formed in substantially flat form. The heat collection unit 20 is disposed to face the back surface of the power generation unit 10 and is formed substantially integrally with the power generation unit 10. A pipe (not shown) through which a heat transfer medium such as an antifreeze liquid can flow is disposed inside the heat collecting unit 20. The heat collection unit 20 can collect the heat of the power generation unit 10 (specifically, solar heat generated by receiving sunlight or heat generated by power generation) by using a heat transfer medium that flows through the pipe. .

  The heat storage tank 30 is for storing heat. The heat storage tank 30 can store the heat transfer medium while keeping the temperature thereof. The heat storage tank 30 is connected to the heat collection unit 20 via the heat collection pipe 31, and the heat transfer medium can circulate between the heat collection part 20 and the heat storage tank 30 via the heat collection pipe 31.

  The heat storage tank 30 is provided with a heat storage tank temperature sensor 32 that can detect the temperature in the heat storage tank 30 (the heat transfer medium stored in the heat storage tank 30). The heat storage tank temperature sensor 32 is provided in the lower part of the heat storage tank 30, and detects the temperature of the heat transfer medium stored in the lower part of the heat storage tank 30 (that is, a heat transfer medium having a relatively low temperature in the heat storage tank 30). Is possible.

  The heat collection pump 40 is an embodiment of the pump according to the present invention. The heat collection pump 40 is for circulating a heat transfer medium between the heat collection unit 20 and the heat storage tank 30. The heat collection pump 40 is provided in the middle of the heat collection pipe 31, and circulates the heat transfer medium between the heat collection section 20 and the heat storage tank 30 by pumping the heat transfer medium in the heat collection pipe 31. Can do.

  The heat exchanger 50 is for transferring the heat of the heat transfer medium to water. The heat exchanger 50 is connected to the heat storage tank 30 via the circulation pipe 51, and the heat transfer medium can circulate between the heat storage tank 30 and the heat exchanger 50 via the circulation pipe 51.

  The hot water pump 60 is for circulating a heat transfer medium between the heat storage tank 30 and the heat exchanger 50. The hot water pump 60 is provided in the middle of the circulation pipe 51, and can circulate the heat transfer medium between the heat storage tank 30 and the heat exchanger 50 by pumping the heat transfer medium in the circulation pipe 51.

  The hot water supply facility 70 is for supplying hot water to a house (for example, a bathtub in a bathroom). A hot water supply pipe 71 is connected to the hot water supply facility 70. The hot water supply pipe 71 guides clean water to the hot water supply equipment 70, and is arranged so that a midway portion thereof passes through the heat exchanger 50.

  The main controller 100 is for controlling the operation of the system 1. The main control device 100 includes a storage unit such as a RAM and a ROM, an arithmetic processing unit such as a CPU, and the like.

Main controller 100 is electrically connected to power sensor 12 and can obtain a detection result output from power sensor 12.
The main controller 100 is electrically connected to the temperature sensor 32 in the heat storage tank, and can acquire the detection result output from the temperature sensor 32 in the heat storage tank.

The main controller 100 is electrically connected to the heat collecting pump 40 and can control the operation of the heat collecting pump 40.
The main controller 100 is electrically connected to the hot water pump 60 and can control the operation of the hot water pump 60.

  Below, the outline of a mode that the system 1 comprised as mentioned above is drive | operated is demonstrated.

  When sunlight is irradiated to the power generation unit 10, electric power is generated in the power generation unit 10, and the electric power is supplied to a load or the like in the house. Moreover, when sunlight is irradiated to the power generation part 10, the heat | fever (solar heat) by the said sunlight and the heat accompanying electric power generation generate | occur | produce. The heat is collected in the heat collection unit 20 and further conveyed (collected) to the heat storage tank 30 by a heat transfer medium circulated by the heat collection pump 40. That is, the heat transfer tank 30 stores the heat transfer medium having a high temperature.

  When the hot water pump 60 is further driven, the heat (high temperature heat transfer medium) of the heat storage tank 30 is carried to the heat exchanger 50 by the heat transfer medium circulated by the hot water pump 60. In the heat exchanger 50, the heat of the heat transfer medium is transmitted to the hot water flowing through the hot water supply pipe 71, and the hot water (hot water) having reached a high temperature is supplied to the hot water supply facility 70.

  In the heat exchanger 50, the heat transfer medium that has become low temperature by transferring heat to the clean water is returned to the heat storage tank 30, and further circulated to the heat collection unit 20 through the heat collection pipe 31. By circulating the heat transfer medium in this manner, heat can be carried out from the heat collecting unit 20, and thus the temperature increase of the power generation unit 10 can be suppressed, and the power generation efficiency of the power generation unit 10 can be prevented from being reduced or damaged due to high temperatures. can do.

  Below, the outline | summary of control of the driving | operation of the system 1 is demonstrated.

  In the system 1 configured as in the present embodiment, a heat transfer medium is circulated between the heat collection unit 20 that collects the heat of the power generation unit 10 and the heat storage tank 30, and heat is stored in the heat storage tank 30 (heat collection). To do). For this reason, even if the heat transfer medium is circulated unless there is a certain difference between the temperature in the power generation unit 10 and the heat storage tank 30 (the temperature of the power generation unit 10 is somewhat higher than the temperature in the heat storage tank 30). It cannot collect heat efficiently. That is, in the system 1, it is efficient to grasp the temperature of the power generation unit 10 and control the operation based on the temperature (by determining whether or not the temperature of the power generation unit 10 is a heat collecting temperature). It is important for conversion.

  On the other hand, the temperature of the power generation unit 10 greatly depends on the amount of solar radiation. Moreover, since the power generation amount in the power generation unit 10 also greatly depends on the solar radiation amount, it can be expressed as a function of the solar radiation amount. Therefore, it can be said that the temperature of the power generation unit 10 depends on the power generation amount in the power generation unit 10.

  Therefore, in the system 1 in the present embodiment, the temperature of the power generation unit 10 is associated with the integrated value (integrated power generation amount) of the power generation amount in the power generation unit 10, and the operation of the system 1 is controlled based on the integrated power generation amount. More specifically, a threshold value of the integrated power generation amount of the power generation unit 10 is set, and when the integrated power generation amount exceeds the threshold value, the power generation unit 10 rises to a certain temperature (in the power generation unit 10 and the heat storage tank 30). The heat collection pump 40 is driven by determining that a certain difference has occurred in temperature, and heat collection into the heat storage tank 30 is started.

  The threshold used for controlling the operation of the system 1 is set based on the temperature in the heat storage tank 30, the elapsed time from the start of power generation in the power generation section 10, and the temperature of the power generation section 10 estimated from the temperature in the heat storage tank 30.

  By using such a threshold value, it is possible to perform control using detection results by the power sensor 12 that detects the amount of power generation in the power generation unit 10 and the temperature sensor 32 in the heat storage tank 30 that detects the temperature in the heat storage tank 30. The electric power sensor 12 and the temperature sensor 32 in the heat storage tank are considered to be normally installed in order to confirm the state of the solar energy utilization system regardless of the control contents. For this reason, it becomes possible to perform control according to the present embodiment without adding sensors as much as possible.

  Hereinafter, the control of the operation of the system 1 will be described in more detail with reference to FIG.

In step S101, the main controller 100 determines first whether the power generation amount (or generation is started in the power generation portion 10) or E _PV has occurred not in the power generation portion 10 of day.
When it is determined that power generation amount _EPV has been generated, main controller 100 proceeds to step S102.
The main control unit 100 performs when the power generation amount E _PV is determined not occurred, the process of step S101 again.

In step S <b> 102, main controller 100 drives heat collection pump 40 for a predetermined time (for example, about 30 (s)), and pumps the heat transfer medium of heat collection unit 20 into heat storage tank 30.
After performing the process of step S102, main controller 100 proceeds to step S103.

In step S103, main controller 100 stops heat collecting pump 40 that has been driven for a certain period of time.
After performing the process of step S103, main controller 100 proceeds to step S104.

In step S104, the main controller 100, the value of the temperature _{T T} in the heat storage tank 30 immediately after stop of the heat collecting pump 40 is estimated temperature _{T P} of the power generation unit 10.
After performing the process of step S104, main controller 100 proceeds to step S105.

In step S105, the main controller 100 calculates the initial value N ₀ of the integrated power generation threshold value N of the power generation unit 10 used in this control. The calculation of the initial value _{N 0} is used the temperature _{T P} of the power generation portion 10 estimated in step S103.
A method for calculating the initial value N ₀ will be described later.
After performing the process of step S105, main controller 100 proceeds to step S106.

In step S106, the main control unit 100, based on the elapsed time t from the start of power generation in the initial value _{N 0} and the power generation unit 10 updates the threshold N.
A method for updating the threshold value N will be described later.
After performing the process of step S106, main controller 100 proceeds to step S107.

In step S107, the main controller 100 determines whether the integrated value of the power generation amount _{E PV} in the power generation section 10 exceeds the threshold N.
The main control unit 100, when the integrated value of the power generation amount _{E PV} is determined to have exceeded the threshold value N, the process proceeds to step S108.
The main control unit 100, when the integrated value of the power generation amount E _PV is determined not to exceed the threshold value N, the process proceeds to step S106.

In step S <b> 108, main controller 100 drives heat collection pump 40 to circulate the heat transfer medium between heat collection unit 20 and heat storage tank 30. Thereby, the heat of the power generation unit 10 collected by the heat collection unit 20 is further collected in the heat storage tank 30.
After performing the process of step S108, main controller 100 proceeds to step S109.

In step S109, main controller 100 determines whether or not the temperature change amount (time difference) ΔT _T in heat storage tank 30 during driving of heat collection pump 40 has become 0 or less. That is, the main controller 100 determines that the change in temperature T _T in the heat storage tank 30 (increase) runs out, or whether began to decrease.
When the main controller 100 determines that the temperature change amount (time difference) ΔT _T in the heat storage tank 30 has become 0 or less, the main controller 100 proceeds to step S110.
When main controller 100 determines that temperature change amount (time difference) ΔT _T in heat storage tank 30 is not equal to or less than 0, it performs the process of step S109 again.

  In step S110, main controller 100 stops driving heat collecting pump 40.

As described above, main controller 100 drives heat collection pump 40 for a certain period of time (step S102) when power generation amount _EPV is generated for the first time in a day (step S101), and then the heat collection pump. 40 is stopped. The main control unit 100, the temperature _{T T} in the heat storage tank 30 immediately after stop of the heat collecting pump 40, estimates the temperature _{T P} of the power generation portion 10 (step S103), the power generation unit 10 by using the temperature _{T P} An initial value N ₀ of the threshold value N of the integrated power generation amount is calculated (step S105).

Thus, the main controller 100 can, based on the temperature of the heat storage tank 30 (the detection result of the heat storage tank temperature sensor 32), to estimate the temperature T _P of the power generation unit 10. Thus, to provide a sensor for detecting the temperature T _P of the power generation section 10 separately is not necessary, it is possible to prevent an increase in cost.

The main control unit 100 to greater than the integrated value is the threshold N of the power generation amount _{E PV} in the power generation unit 10, every predetermined time (e.g., every 1 minute, etc.) continues to update the threshold value N (step S106). When the integrated value of the power generation amount E _PV exceeds the threshold value N, it is determined that the temperature of the power generation section 10 is increased to some extent (the temperature of the power generation section 10 becomes the heat collecting possible temperature), collector The pump 40 is driven (step S108), and heat is stored in the heat storage tank 30.

When the temperature change amount (time difference) ΔT _T in the heat storage tank 30 during driving of the heat collection pump 40 becomes 0 or less (step S109), the main controller 100 determines the power generation unit 10 (heat collection unit 20). ) Is sufficiently stored in the heat storage tank 30, and the drive of the heat collecting pump 40 is stopped (step S110).

Next, a method for calculating the initial value N ₀ of the threshold value N in step S105 will be described.

The initial value N ₀ is calculated using the following formula 1.

Here, the initial value of the threshold N _T determined tentatively (provisional initial value), N _P is the additional value to account for temperature in the heat storage tank 30 to an initial value N _0.

The provisional initial value _NT of Equation 1 is calculated using Equation 2 below.

Here, a, b and c are positive constants, and T _a is a predetermined reference value. FIG. 3A shows the provisional initial value _NT in a graph.

Provisional initial value N _T is determined based on the temperature T _P of the power generation portion 10 calculated by the heat collecting pump 40 is driven a predetermined time (estimated). Temperature T _P of the power generating unit 10 for influenced by the outside air temperature, it is possible to calculate the threshold value N in consideration of the difference in the temperature of each season.

As the temperature T _P of the power generation section 10 during power generation start is low, the temperature of the power generation section 10 becomes heat collecting possible temperature (increased temperature of the power generation section 10 becomes somewhat higher than the temperature in the heat storage tank 30) The solar energy required by then increases. Therefore, as shown in FIG. 3 (a), the value of the provisional initial value N _T is set such that the temperature T _P of the power generation portion 10 increases as lower. Thus, the lower the temperature _{T P} of the power generation portion 10, the integrated value of the power generation amount _{E PV} required before the heat collecting pump 40 is driven (see step S107) becomes larger.

In the case where the temperature T _P of the power generation section 10 exceeds the reference value T _a is the provisional initial value N _T is a constant value (c), ensures the minimum threshold N (integrated value of the power generation amount E _PV) It shall be.

Also, the addition value N _P in Formula 1 is calculated using the following equation 3.

Here, d and e are positive constants. Those representing the sum value N _P in the graph, shown in FIG. 3 (b).

Addition value N _P is determined based on the temperature T _T in the heat storage tank 30 of the drive immediately before the heat collecting pump 40.

When collecting the heat to the heat storage tank 30, the temperature T _T in the heat storage tank 30 becomes high, it is necessary to increase the temperature of the power generation portion 10 more than that, it is necessary to set the threshold value N be a large value.
Conversely, if the temperature T _T in the heat storage tank 30 is low, by setting the threshold value N to a small value, it is possible to collect the heat to the heat storage tank 30 at an early stage.

Therefore, as shown in FIG. 3 (b), the value of the sum N _P, the temperature T _T in the heat storage tank 30 is increased higher, the temperature T _T in the heat storage tank 30 is the lower the smaller (negative value To be set). The set (see Equation 1) by calculating the initial value N ₀ is added to the provisional initial value N _T the addition value N _P was as, taking into account the temperature in the heat storage tank 30 to an initial value N ₀ Can do.

However, since the addition value N _P can take a negative value as described above, when the addition value N _P is added to the provisional initial value N _T in Equation 1, the initial value N ₀ is a negative value or a positive value. Even a value may take an extremely small value. Therefore, upon adding the additional value N _P provisional initial value N _T In Equation 1, the initial value N ₀ is set in advance so as not to fall below a predetermined lower limit value.

  Next, a method for updating the threshold value N in step S106 will be described.

  The threshold value N is updated using the following equation (4).

Here, t (min) elapsed time from the start of power generation in the power generation portion 10, t _b is the predetermined reference value. F is a positive constant. FIG. 4 shows the threshold value N in a graph.

Temperature of the power generation portion 10, as the integrated value of the same power generation amount E _PV is obtained easily rises higher insolation. For example, even if the integrated value of the same power generation amount E _PV is obtained, the temperature of the power generation portion 10 than Day towards sunny day the cloudy increases. In order to reflect the difference due to the weather on the threshold value N, the threshold value N is changed according to the elapsed time t.

Specifically, the threshold N remains constant at the initial value N ₀ until t _b (minutes) has elapsed from the start of power generation in the power generation unit 10. Here, the reference value t _b, the temperature of the power generation unit 10 in the sunny day is set the time required to rise to the heat collector can be temperature. The time (reference value t _b ) is determined in advance by experiment, numerical analysis, or the like.

On the other hand, after t _b (min) has elapsed since the start of power generation in the power generation unit 10, the threshold value N is increased by f (%) of the initial value N ₀ every minute. Thereby, when the amount of solar radiation is low, such as on a cloudy day, it is possible to consider the slowing tendency of the temperature rise of the power generation unit 10.

Below, the specific example of control of the system 1 in each of a fine day, a cloudy day, and a rainy day is demonstrated using FIG.5 and FIG.6.
The temperature T _P of the power generation unit 10 shown in FIG. 5 and FIG. 6 shows the actually measured values in order to see how the control system 1 (measured value), as described above there is no need to actually measure the temperature T _P of the power generation portion 10 to the control of the system 1.

FIG. 5A shows a specific example when the system 1 is controlled on a sunny day. A sunny day, at the time of the lapse of about t _b min from the start of power generation in the power generation unit 10, the integrated value of the power generation amount E _PV exceeds the threshold value N, from that point to the drive (heat storage tank 30 of the heat collecting pump 40 Heat collection) is started.

In this case, paying attention to the temperature T _P of the power generation unit 10, the power generation amount when the integrated value exceeds the threshold value N of E _PV, the temperature T _P is heat collecting possible temperature (temperature in the heat storage tank 30 of the power generation portion 10 the difference between T _T ([Delta] T _PT) is increased sufficiently to some extent larger temperature).

FIG. 5B shows a specific example when the system 1 is controlled on a cloudy day. In cloudy days, at the time it has elapsed about t _b min from the start of power generation in the power generation unit 10, not yet integrated value of the power generation amount E _PV exceeds the threshold N. Further, at this time, (a small difference between the temperature T _T in the heat storage tank 30) of the temperature T _P of the power generation portion 10 is not increased to the heat collector capable temperature.

In cloudy days, when older than t _b min from the start of power generation in the power generation unit 10, the integrated value of the power generation amount E _PV exceeds the threshold value N, from that point to the drive (heat storage tank 30 of the heat collecting pump 40 Heat collection) is started. At this point, have risen enough to the temperature T _P is heat collecting possible temperature of the power generation section 10 (the difference between the temperature T _T in the heat storage tank 30 ([Delta] T _PT) temperature increases to some extent).

FIG. 6 shows a specific example when the system 1 is controlled on a rainy day. On the day of rain, since a small power generation amount E _PV in the power generation unit 10, the integrated value does not exceed the threshold N. That is, on a rainy day, the heat collection pump 40 is not driven (heat collection to the heat storage tank 30 is not performed).

In this case, paying attention to the temperature T _P of the power generation unit 10, the temperature T _P is heat collecting possible temperature of the power generation portion 10 is not increased to (the difference between the temperature T _T in the heat storage tank 30 is somewhat larger temperature) . That is, in this case, inefficient driving of the heat collecting pump 40 can be prevented.

As described above, the system 1 (solar energy utilization system) according to the present embodiment is
A power generation unit 10 capable of generating power using sunlight;
A heat collecting unit 20 capable of collecting heat of the power generation unit 10, and
A heat storage tank 30 capable of storing heat;
A heat transfer medium that can circulate between the heat collecting section 20 and the heat storage tank 30, and
A heat collecting pump 40 (pump) for circulating the heat transfer medium;
A power sensor 12 (power generation amount detecting means) for detecting the power generation amount in the power generation unit 10;
Comprising
Integrated value of the power generation amount E _PV in the power generation portion 10 is calculated, the cumulative value is what heat is stored in the thermal storage tank 30 heat collecting pump 40 is driven when it exceeds a predetermined threshold N.
With this configuration, efficient operation is possible while preventing an increase in cost due to an increase in sensors. That is, since control is performed using the normally provided power sensor 12, it is not necessary to provide separate sensors.

In addition, the system 1
A heat storage tank temperature sensor 32 (heat storage tank temperature detection means) for detecting the temperature in the heat storage tank 30;
The predetermined threshold N is
Is to be determined based on the heat collection pump 40 to a temperature T _P of the power generation portion 10 to be estimated from the temperature T _T in the heat storage tank 30 after being driven for a predetermined time period when the power generator 10 starts power generation .
With this configuration, efficient operation is possible while preventing an increase in cost due to an increase in sensors. That is, since control is performed using the heat storage tank temperature sensor 32 that is normally provided, there is no need to provide separate sensors. Further, the temperature T _P of the power generation unit 10 estimates, based from the heat collector 20 to a temperature T _T in the heat storage tank 30 after the heat transfer medium to the heat storage tank 30 is transported, determines a predetermined threshold value N it is, it is possible to set a threshold value N based on the temperature T _P of the power generation unit 10.

The predetermined threshold N is
Temperature T _P of the estimated power generation section 10 is one that is determined to be higher as lower.
By configuring in this way, an appropriate threshold value N can be determined. That is, many integrated value of the power generation amount E _PV to a temperature T _P of estimated power generating unit 10 drives the lower the heat collecting pump 40 (i.e., the threshold value N increases) by the temperature of the power generation portion 10 it is possible to ensure a longer time to raise the T _P.

The predetermined threshold N is
It is updated so as to increase in accordance with the elapsed time t from the start of power generation by the power generation unit 10.
With this configuration, the threshold value N can be updated to an appropriate value. That is, even an integrated value of the power generation amount E _PV is the same, the temperature T _P of the power generation portion 10 the lower the amount of solar radiation is hard to rise. Therefore, when such a low amount of solar radiation (i.e., the power generation amount increases when the slow state of the integrated value of E _PV) increases the threshold value N to the time for raising the temperature T _P of the power generation portion 10 more It can be secured for a long time.

The predetermined threshold N is
In which the power generation unit 10 is determined to be higher the higher the temperature T _T of the heat storage tank 30 immediately before the start of the power generation.
By configuring in this way, an appropriate threshold value N can be determined. That is, when the temperature T _P of the power generation portion 10 is not somewhat higher than the temperature T _T in the heat storage tank 30, it is impossible to store heat efficiently be circulated heat transfer medium to the heat storage tank 30. Therefore, by increasing and decreasing the threshold value N in response to the temperature T _T in the heat storage tank 30, it is possible to secure the time for raising the temperature T _P of the power generation unit 10 to a suitable temperature.

  In addition, the structure of the system 1 demonstrated in this embodiment is an example, and the solar energy utilization system which concerns on this invention can be comprised arbitrarily.

  The constants (a, b, c, d, e, and f) shown in the present embodiment can be set to appropriate values through experiments, numerical analysis, and the like.

  Moreover, the solar energy utilization system according to the present invention can be applied not only to a house but also to various facilities (a collective house, a commercial facility, an experimental facility, etc.).

1 system (solar energy utilization system)
10 power generation unit 12 power sensor (power generation amount detection means)
20 heat collection part 30 heat storage tank 32 temperature sensor in heat storage tank (heat storage tank temperature detection means)
40 Heat collection pump (pump)
100 Main controller

Claims (4)

A power generation unit capable of generating power using sunlight;
A heat collecting unit capable of collecting heat of the power generation unit;
A heat storage tank capable of storing heat;
A heat transfer medium that can circulate between the heat collecting section and the heat storage tank;
A pump for circulating the heat transfer medium;
A power generation amount detecting means for detecting a power generation amount in the power generation section;
A heat storage tank temperature detecting means for detecting the temperature in the heat storage tank;
Comprising
An integrated value of the power generation amount in the power generation unit is calculated, and when the integrated value exceeds a predetermined threshold, the pump is driven to store heat in the heat storage tank,
The predetermined threshold is:
It is determined based on the temperature of the power generation unit estimated from the temperature in the heat storage tank after driving the pump for a predetermined time when the power generation unit starts power generation,
Solar energy utilization system. The predetermined threshold is:
It is determined to be higher as the estimated temperature of the power generation unit is lower,
The solar energy utilization system according to claim 1. The predetermined threshold is:
Updated to increase according to the elapsed time from the start of power generation by the power generation unit,
The solar energy utilization system according to claim 1 or 2. The predetermined threshold is:
It is determined to be higher as the temperature in the heat storage tank immediately before the power generation unit starts power generation,
Solar energy utilization system as claimed in any one of claims 1 to 3.

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