JP2021021520A - Cogeneration system - Google Patents

Abstract

To provide a cogeneration system capable of suppressing generation of excessive heat by storing waste heat of a power generation part in a heat storage tank in which a latent heat storage material is accommodated, and utilizing the waste heat for heating, further, storing high-temperature heat effectively available for heating and making low a temperature of hot water distributed to a waste heat recovery and heat exchange unit.SOLUTION: A flow passage 27 for warming and a heated passage 28 for heating are provided inside of a heat storage tank J in which a latent heat storage material is accommodated. A flow rate control unit V which changes and controls a ratio of a flowing quantity for warming to flow through the flow passage 27 for warming to an outgoing passage 9a for hot water storage of a hot water distribution passage 9 and a flowing quantity to flow though a hot water storage tank 8 to the outgoing passage 9a for hot water storage in hot water flowing through a returning passage 9b for hot water storage of the hot water distribution passage 9, executes temperature control processing for maintaining a temperature of hot water in the outgoing passage 9a for hot water storage at a preset cooling temperature.SELECTED DRAWING: Figure 1

Description

The present invention is in the form of passing through a power generation unit that operates by supplying fuel, a closed type hot water storage tank that stores hot water, and an exhaust heat recovery heat exchange unit that recovers exhaust heat of the power generation unit. A hot water circulation path for connecting the bottom and the top, a hot water circulation pump for circulating hot water through the hot water circulation path in a form of returning the hot water taken out from the bottom of the hot water storage tank to the upper part of the hot water storage tank, and a hot water circulation pump. An operation control unit is provided,
In order for the operation control unit to store hot water in a state where a temperature stratification is formed in the hot water storage tank in the operating state of the power generation unit, the temperature of hot water supplied to the upper part of the hot water storage tank through the hot water circulation path becomes the target temperature. The present invention relates to a combined heat and power system configured to execute an exhaust heat recovery type hot water storage process that controls the operation of the hot water circulation pump in a form of adjusting the amount of hot water circulating through the hot water circulation path.

Such a combined heat and power system is installed in a general household or the like to supply the electric power generated by the power generation unit to an electric load, and recovers the exhaust heat of the power generation unit to heat the hot water in the hot water storage tank to store hot water. The hot water in the tank can be supplied to the hot water consumption part such as a hot water tap.
Incidentally, the power generation unit includes a fuel cell (for example, a solid oxide fuel cell, etc.) and an engine-driven generator.

As a conventional example of such a combined heat and power system, a heating heating path branched from a hot water storage return path connecting an exhaust heat recovery heat exchange unit and an upper part of a hot water storage tank in a hot water circulation path bypasses the hot water storage tank and circulates hot water. It is provided in a state of being connected to a hot water storage outbound path that connects the bottom of the hot water storage tank and the exhaust heat recovery heat exchange section in the road, and in the heating heating path, the hot water flowing through the heating heating path and the heating terminal. A heating heat exchange section is provided to exchange heat with the heating heat medium that flows through the heating circulation path that circulates and supplies the heating heat medium, and the hot water that flows through the hot water storage return path flows into the hot water storage tank. There is a combined heat and power system provided with a three-way valve that switches the hot water flowing through the return path to a state in which it flows to the heat exchange section for heating (see, for example, Patent Document 1).

That is, Patent Document 1 describes a heating heat medium that flows through a heating circulation path by switching to a state in which hot water having a target temperature (for example, 65 ° C.) flowing through the hot water storage return path is allowed to flow through the heating heat exchange section. By heating the above, the heating operation can be performed in the form of utilizing the exhaust heat of the power generation unit.
Incidentally, in Patent Document 1, a radiator for cooling hot water is provided on the outbound route for storing hot water, and when the temperature of hot water is higher than the set cooling temperature, the radiator is operated to lower the temperature of hot water. Has been done.

Further, as another conventional example of the combined heat and power system, the latent heat storage type heat storage tank has a lower high temperature side tank portion containing a high temperature side latent heat storage material having a high melting point and a low temperature side latent heat storage material having a low melting point. A heat storage branch path branched from the hot water storage outbound path that connects the bottom of the hot water storage tank and the exhaust heat recovery heat exchange section in the hot water circulation path is provided in a state of being separated from the upper low temperature side tank part that stores the heat storage. , It is installed in a state where hot water is flowed from the lower side to the upper side of the heat storage tank and then returned to the outbound route for hot water storage, and the hot water discharged from the bottom of the hot water storage tank does not go through the heat storage tank. A valve is provided to switch between the state of flowing to the exhaust heat recovery heat exchange section and the state of flowing to the exhaust heat recovery heat exchange section via the heat storage tank, and for heating, which is branched from the hot water outlet connected to the upper part of the hot water storage tank. A branch path is provided in a state where hot water is flowed from the upper side to the lower side of the heat storage tank and then returned to the hot water passage, and the hot water discharged from the upper part of the hot water tank does not pass through the heat storage tank. There is a combined heat and power system provided with a valve for switching between a state of flowing through a hot water passage and a state of flowing through a hot water passage while passing through a heat storage tank (see, for example, Patent Document 2).

That is, in Patent Document 2, when the amount of hot water stored in the hot water storage tank is full, the high-temperature hot water discharged from the bottom of the hot water storage tank is allowed to flow through the heat storage tank to store heat in the heat storage tank. And when the amount of hot water stored in the hot water storage tank is exhausted, the low-temperature hot water discharged from the upper part of the hot water storage tank is made to flow through the hot water channel while being heated by flowing through the heat storage tank. It is a thing.

Japanese Patent No. 5551971 JP-A-2010-186668

In the combined heat and power system of Patent Document 1, the use of exhaust heat for heating is limited to the exhaust heat generated during the heating operation, and the power generation unit (fuel cell, etc.) installed in a general household. Since the amount of exhaust heat is not so large, it is difficult to cover all of the heating load with the exhaust heat of the power generation unit (fuel cell, etc.).

In the combined heat and power system of Patent Document 1, even in such a situation, the fuel cell (particularly the solid oxide fuel cell) as the power generation unit should be continuously operated for 24 hours in order to ensure the durability. If this is the case, there is a possibility that a surplus of heat will be generated to fill the amount of hot water stored in the hot water storage tank, and it may be necessary to operate the radiator of the hot water storage outbound route to dissipate heat.

By the way, it is conceivable to store the exhaust heat for the use of heating, but in this case, if the heat is stored using hot water, the size of the heat storage tank becomes large, which causes a disadvantage.

In the combined heat and power system of Patent Document 2, since a heat storage tank for storing the latent heat storage material is provided, it is possible to increase the amount of heat stored in the exhaust heat of the power generation unit while reducing the size of the heat storage tank.
However, since the heat storage tank includes two types of latent heat storage materials, one on the low temperature side and the other on the high temperature side, there is a disadvantage that the configuration of the heat storage tank is complicated and expensive.

That is, in order to store heat until the latent heat storage material melts and becomes a liquid, it is necessary for hot water to enter at a temperature higher than the melting point of the latent heat storage material and exit at a temperature higher than the melting point.
On the other hand, the temperature of the hot water flowing in the exhaust heat recovery heat exchange section needs to be suppressed to the set cooling temperature (for example, 40 ° C.) or less in order to secure the exhaust heat recovery performance.
Therefore, when the hot water discharged from the bottom of the hot water tank is made to flow through the heat storage tank when the amount of hot water stored in the hot water tank is full, there are two types of latent heat storage materials, the low temperature side and the high temperature side. It was necessary to equip the heat storage tank with a complicated and expensive heat storage tank.

By the way, if one kind of latent heat storage material is to be provided, the latent heat storage material on the low temperature side will be provided, but in this case, only a low temperature that is not easy to use can be obtained, and it is easy to use. In order to obtain a good high temperature, it is necessary to provide two types of latent heat storage materials, a low temperature side and a high temperature side.

In the combined heat and power system of Patent Document 2, the use of heat storage for heating is not described, but tentatively, a heating heat medium that flows through a heating circulation path that circulates and supplies a heating heat medium to a heating terminal is used. Assuming that the heating is performed through the heat storage tank, when the temperature of the heating heat medium returning to the heat storage tank is higher than the melting point of the latent heat storage material on the low temperature side, the latent heat storage material on the low temperature side from the heating heat medium There is a possibility that inconvenience may occur in which heat is supplied (heat is taken away).

The present invention has been made in view of the above circumstances, and an object of the present invention is to store heat exhausted from a power generation unit in a heat storage tank containing a latent heat storage material and use it for heating, thereby generating heat surplus. While using one type of latent heat storage material for the heat storage tank, it stores high-temperature heat that can be effectively used for heating and lowers the temperature of hot water flowing to the exhaust heat recovery heat exchange section. The point is to provide a combined heat and power system that can be used.

The combined heat and power system of the present invention passes through a power generation unit that operates by supplying fuel, a closed hot water storage tank that stores hot water, and an exhaust heat recovery heat exchange unit that recovers exhaust heat from the power generation unit. Hot water circulation path for flowing hot water that connects the bottom and top of the hot water storage tank, and hot water that circulates hot water through the hot water circulation path in the form of returning the hot water taken out from the bottom of the hot water storage tank to the upper part of the hot water storage tank. A circulation pump and an operation control unit are provided,
The temperature of the hot water supplied to the upper part of the hot water storage tank through the hot water circulation path is the target temperature so that the operation control unit stores hot water in a state where the hot water storage tank is formed with a temperature stratification in the operating state of the power generation unit. In this way, the amount of hot water circulating through the hot water circulation path is adjusted, and the waste heat recovery type hot water storage process that controls the operation of the hot water circulation pump is executed. ,
Inside the heat storage tank containing the latent heat storage material, each of the heating flow path and the heated passage for heating is provided so as to be located from one end to the other end of the heat storage tank.
The heating circulation path that circulates and supplies the heating heat medium to the heating terminal connects the heating return path to the heating inlet on one end side of the heating heated path, and connects the heating outbound path to the heating. It is provided in a state of being connected to the heating outlet on the other end side of the heated passage.
The return side branch path branched from the hot water storage return path connecting the exhaust heat recovery heat exchange section and the upper part of the hot water storage tank in the hot water circulation path serves as a heating inlet on the other end side of the heating flow path. The forward side junction flow path that is connected and joins the hot water storage outbound path that connects the bottom of the hot water storage tank and the exhaust heat recovery heat exchange section in the hot water circulation path is on one end side of the heating flow path. Connected to the heating outlet,
Of the hot water flowing through the hot water storage return path, the amount of hot water that flows to the hot water storage outbound path via the heating flow path and the amount of hot water that flows to the hot water storage outbound path via the hot water storage tank. When the temperature of the hot water flowing in the forward side joint flow path is equal to or lower than the set cooling temperature, the flow rate adjusting unit for changing and adjusting the ratio with the flow rate for hot water storage makes the flow rate for hot water storage zero. When the temperature of the hot water flowing in the outgoing side junction flow path exceeds the set cooling temperature, the temperature of the hot water water downstream from the confluence of the outgoing side junction flow path in the hot water storage outbound passage is maintained at the set cooling temperature. Therefore, the temperature control process for adjusting the ratio between the heating flow rate and the hot water storage flow rate is configured to be executed.

That is, when the amount of heat stored in the heat storage tank is small (such as when the latent heat storage material is not melted), the entire amount of hot water flowing through the hot water storage return path of the hot water circulation path is allowed to flow through the heating flow path of the heat storage tank. However, the amount of heat stored in the heat storage tank is such that the temperature of the hot water flowing in the forward-side joint flow path connected to the heating outlet of the heating flow path becomes lower than the set cooling temperature, and the latent heat storage material begins to melt. As the temperature increases, the temperature of the hot water flowing in the forward side joint flow path gradually rises, and then the temperature of the hot water rises to the extent that it exceeds the set cooling temperature.

Therefore, when the amount of heat stored in the heat storage tank is small, the total amount of hot water flowing through the hot water storage return path of the hot water circulation path is passed through the heating flow path of the heat storage tank by the operation of the flow rate adjusting unit, and the heat storage of the heat storage tank is performed. Is advanced.
After that, as the amount of heat stored in the heat storage tank increases, when the temperature of the hot water flowing in the forward-side joint flow path rises to a extent that exceeds the set cooling temperature, the temperature control process of the flow rate control unit opens the heating flow path. The ratio of the amount of heating flow that flows to the hot water storage outbound route via the hot water storage tank and the amount of hot water storage flow that flows to the hot water storage outbound route via the hot water storage tank is changed and adjusted, and joins the outbound side in the hot water storage outbound route. The temperature of the hot water on the downstream side of the confluence of the roads is maintained at the set cooling temperature, and the hot water is stored in the hot water storage tank.

Then, the heating heat medium flowing through the heating circulation path is heated by flowing through the heating heating path inside the heat storage tank, and the heated heating heat medium is circulated and supplied to the heating terminal. As a result, heating is performed using the heat stored in the heat storage tank.
In addition, hot water can be discharged (hot water supply) using the hot water stored in the hot water storage tank.

In this way, the exhaust heat of the power generation unit is stored in the heat storage tank and used for heating, and the hot water is stored in the hot water storage tank. Therefore, the exhaust heat of the power generation unit is the heat storage in the heat storage tank and the hot water storage in the hot water storage tank. By using the above, it is possible to suppress the generation of so-called heat surplus, in which the exhaust heat of the power generation unit cannot be used for heat storage in the heat storage tank or hot water storage in the hot water storage tank.

Moreover, a heating passage is provided inside the heat storage tank in a state of being located from one end to the other end of the heat storage tank, and a heating heat medium flowing through the heating circulation path is heated for heating. The heating flow path is located inside the heat storage tank from the heating inlet on one end side to the heating outlet on the other end side of the path from one end to the other end of the heat storage tank. In addition, the hot water from the hot water storage return path is allowed to flow from the heating inlet on the other end side of the heating flow path to the heating outlet on the one end side, and in addition, a heat storage tank is provided. Since the hot water that has passed through and the hot water from the bottom of the hot water storage tank are mixed, high-temperature heat that can be effectively used for heating is stored and discharged while using one type of latent heat storage material to be stored in the heat storage tank. The temperature of the hot water flowing in the heat recovery heat exchange unit can be lowered.

That is, the hot water flowing through the hot water storage return path in the hot water circulation path is maintained at the target temperature (for example, 65 ° C.), and the heating heat medium flowing through the heating circulation path is the temperature of the hot water (for example, 65 ° C.). It is preferable to heat to a temperature similar to the target temperature), and the temperature of the heat medium that flows through the heating circulation path and passes through the heating terminal is the target of the hot water that flows through the hot water storage return path. In view of the fact that the temperature is lower than the temperature (for example, 65 ° C.), hot water having a target temperature (for example, 65 ° C.) is applied from the heating inlet on the other end side of the heating flow path to the heating outlet on the one end side. Latent heat stored in the heat storage tank so that the heating medium flows toward and from the heating inlet on one end side of the heated path for heating toward the heating outlet on the other end side. Even though one type of heat storage material is used, the high-temperature heat stored in the heat storage tank can be effectively used for heating.

In addition, the hot water that has passed through the heat storage tank and the low-temperature hot water from the bottom of the hot water storage tank are mixed, and the temperature of the hot water that flows to the exhaust heat recovery heat exchange section is maintained at a low temperature, in other words, at the set cooling temperature. By using one type of latent heat storage material to be stored in the heat storage tank, even if the hot water that has passed through the heat storage tank becomes hot, the hot water that flows to the exhaust heat recovery heat exchange section The temperature can be kept low.

In short, according to the characteristic configuration of the combined heat and power supply system of the present invention, the exhaust heat of the power generation unit is stored in the heat storage tank containing the latent heat storage material and used for heating, thereby suppressing the generation of excess heat. Moreover, while using one type of latent heat storage material in the heat storage tank, it is possible to store high-temperature heat that can be effectively used for heating and lower the temperature of hot water flowing to the exhaust heat recovery heat exchange section.

A further characteristic configuration of the combined heat and power supply system of the present invention is such that hot water can be supplied through the hot water outlet connected to the upper part of the hot water storage tank at the water supply pressure of the water supply channel connected to the bottom of the hot water storage tank.
The hot water outlet branch path branched from the hot water outlet is connected to the outgoing hot water branch flow path and joins the hot water discharge branch path downstream of the branch point of the hot water branch path in the hot water outlet. Connected to the return branch,
The basic hot water state in which the entire amount of hot water flowing in the hot water passage is flowed without branching to the hot water branch path, and the total amount of hot water flowing in the hot water channel is branched into the hot water branch path to the outgoing side. A hot water discharge state switching unit for switching between a hot water discharge state, a heating flow path, a return side branch path, and a heat storage tank heating hot water discharge state in which the hot water flows through the hot water discharge joint flow path is provided.

That is, when the hot water state switching unit is switched to the basic hot water state, as described above, when the amount of heat stored in the heat storage tank is small, the total amount of hot water flowing through the hot water storage return path of the hot water circulation path becomes the heating flow path of the heat storage tank. The heat is passed through and the heat storage in the heat storage tank is promoted, and as the amount of heat stored in the heat storage tank increases, the hot water storage in the hot water storage tank is promoted.

In winter, etc., the heat stored in the heat storage tank is used for heating, but even in the season when heating is not used, when the amount of hot water stored in the hot water storage tank is low, the hot water discharge state switching unit is heated to the heat storage tank. By switching to the state, the hot water discharged from the upper part of the hot water storage tank can be heated by the heat stored in the heat storage tank and discharged.

In short, according to the further characteristic configuration of the combined heat and power system of the present invention, the heat stored in the heat storage tank can be effectively used for hot water even in the season when heating is not used.

A further characteristic configuration of the combined heat and power supply system of the present invention is that when the operation control unit switches the hot water discharge state switching unit to the basic hot water discharge state and the amount of hot water stored in the hot water storage tank becomes less than the set value. When the amount of heat stored in the heat storage tank is equal to or greater than the allowable operating amount, the hot water discharge state switching unit is configured to switch to the hot water discharge state heated in the heat storage tank.

That is, by switching the hot water discharge state switching unit to the basic hot water discharge state, the operation control unit heats using the heat stored in the heat storage tank in winter or the like, and the hot water is stored in the hot water storage tank. Hot water can be used for hot water supply.

In addition, when the operation control unit switches the hot water discharge state switching unit to the basic hot water discharge state and the heat storage amount in the hot water storage tank is less than the set value, the heat storage amount in the heat storage tank is equal to or greater than the operation allowable amount. Since the hot water discharge state switching unit is switched to the heat storage tank heating hot water discharge state, hot water can be discharged (hot water supply) by using the hot water stored in the hot water storage tank or the heat stored in the heat storage tank.

That is, for example, when the power generation unit (for example, a solid oxide fuel cell) is to be continuously operated for 24 hours, if the hot water discharge state switching unit is switched to the basic hot water discharge state, the power generation unit Since the exhaust heat is stored in the heat storage tank and stored in the hot water storage tank, the hot water stored in the hot water storage tank is used to discharge the hot water. However, during times when the hot water consumption is high, the hot water storage tank is used. There is a risk that the amount of hot water stored in the hot water will be insufficient (the amount of hot water stored in the hot water tank will be less than the set value).
In such a case, if the amount of heat stored in the heat storage tank is equal to or greater than the allowable operating amount, the operation control unit switches the hot water discharge state switching unit to the heat storage tank heating hot water discharge state. Therefore, the heat stored in the heat storage tank You can also use the hot water.

Therefore, in the heating season such as winter, the heat stored in the heat storage tank can be used for heating, and the heat stored in the heat storage tank can also be used to discharge hot water. Yes, usability is improved.

In short, according to a further characteristic configuration of the combined heat and power supply system of the present invention, hot water can be discharged by using the heat stored in the heat storage tank, which improves usability.

A further characteristic configuration of the combined heat and power supply system of the present invention is that when the operation control unit is switched to the hot water discharge state of the heat storage tank, if the heat storage amount of the heat storage tank is equal to or less than the operation stop amount, the hot water discharge state The point is that the switching unit is configured to switch to the basic hot water discharge state.

That is, when the amount of heat stored in the hot water storage tank becomes less than the set value and the amount of heat stored in the heat storage tank is equal to or greater than the allowable operating amount, the operation control unit switches the hot water discharge state switching unit to the hot water discharge state of the heat storage tank. In addition, if the amount of heat stored in the heat storage tank is equal to or less than the amount of operation stop, the operation control unit switches the hot water discharge state switching unit to the basic hot water discharge state, so that the temperature of the hot water supplied through the hot water outlet fluctuates rapidly. It is possible to avoid the risk of hot water and to discharge hot water satisfactorily.

That is, when the heat storage amount in the heat storage tank is low when the hot water is switched to the heat storage tank heating hot water state, the temperature of the hot water heated in the heat storage tank may suddenly fluctuate. According to the amount of heat storage generated, the operation stop amount for the heat storage amount of the heat storage tank is determined, and when the heat storage amount of the heat storage tank becomes less than the operation stop amount, it is supplied through the hot water outlet by switching to the basic hot water discharge state. It is possible to avoid the possibility that the temperature of the hot water suddenly fluctuates up and down.

In short, according to a further characteristic configuration of the combined heat and power supply system of the present invention, it is possible to satisfactorily discharge hot water while avoiding the possibility that the temperature of the hot water supplied through the hot water passage suddenly fluctuates up and down.

A further characteristic configuration of the combined heat and power system of the present invention is a temperature sensor on the other end side that detects the temperature on the other end side inside the heat storage tank and one end side that detects the temperature on the one end side inside the heat storage tank. A temperature sensor is provided,
When the operation control unit detects a set high temperature side temperature higher than the melting point of the latent heat storage material by each of the other end side temperature sensor and the one end side temperature sensor, the heat storage amount of the heat storage tank is the operation permit. When it is determined that the capacity is equal to or higher than the capacity and the one end side temperature sensor detects a set low temperature side temperature lower than the melting point of the latent heat storage material, it is determined that the heat storage amount of the heat storage tank is equal to or less than the operation stop amount. It is in the point that it is configured to do.

That is, the latent heat storage material stored inside the heat storage tank stores heat by flowing high-temperature hot water from the other end to one end of the heating flow path inside the heat storage tank. When storing heat in the tank, the temperature of the entire latent heat storage material becomes high in a state where the temperature of the other end side portion of the latent heat storage material becomes higher than that of the one end side portion.

Therefore, the temperature sensor on the other end side that detects the temperature on the other end side inside the heat storage tank and the temperature sensor on the one end side that detects the temperature on the one end side inside the heat storage tank are more than the melting point of the latent heat storage material. The state in which the high set high temperature side temperature is detected is the state in which the entire latent heat storage material housed inside the heat storage tank is sufficiently storing heat, so that the operation control unit performs the operation control unit with the other end side temperature sensor and When each of the one-end side temperature sensors detects the set high temperature side temperature higher than the melting point of the latent heat storage material, it is determined that the heat storage amount of the heat storage tank is equal to or more than the operation allowable amount.

By the way, when heat is stored in the heat storage tank, the temperature of the latent heat storage material as a whole becomes high in a state where the temperature of the other end side portion of the latent heat storage material becomes higher than that of the one end side portion. When the temperature sensor on the one end side detects the set high temperature side temperature higher than the melting point of the latent heat storage material, it can be determined that the amount of heat stored in the heat storage tank is equal to or greater than the allowable operating amount, but the temperature sensor on the one end side fails. When the temperature on the other end side does not detect the set high temperature side temperature higher than the melting point of the latent heat storage material when the set high temperature side temperature higher than the melting point of the latent heat storage material is detected, the amount of heat stored in the heat storage tank Can be determined not to exceed the operating allowance.

Further, when the heat storage tank dissipates heat in the state where the hot water is discharged from the heat storage tank, the low-temperature hot water flows from one end to the other end of the heating flow path inside the heat storage tank to dissipate heat. Therefore, when the heat storage tank dissipates heat, the heat dissipation of the latent heat storage material proceeds in a state where the temperature of the one end side portion of the latent heat storage material becomes lower than that of the other end side portion.

Therefore, of the other end side temperature sensor that detects the other end side temperature inside the heat storage tank and the one end side temperature sensor that detects the one end side temperature inside the heat storage tank, the one end side temperature sensor is The state in which the set low temperature side temperature lower than the melting point of the latent heat storage material is detected is the state in which the amount of heat storage of the latent heat storage material stored inside the heat storage tank is small, so that the operation control unit is at one end. When the side temperature sensor detects the set low temperature side temperature lower than the melting point of the latent heat storage material, it is determined that the heat storage amount of the heat storage tank is equal to or less than the operation stop amount.

In short, according to the further characteristic configuration of the combined heat and power system of the present invention, it is appropriately determined that the heat storage amount of the heat storage tank is equal to or more than the operation allowable amount and that the heat storage amount of the heat storage tank is equal to or less than the operation stop amount. it can.

It is a schematic block diagram of a combined heat and power system. It is a schematic block diagram which shows the heat storage state. It is a schematic block diagram which shows the hot water storage heat storage state. It is a schematic block diagram of the combined heat and power system of another embodiment. It is a schematic block diagram which shows the basic hot water discharge state. It is a schematic block diagram which shows the hot water discharge state of a heat storage tank.

[Embodiment]
Hereinafter, embodiments of the combined heat and power system of the present invention will be described with reference to the drawings.
(Overall configuration of combined heat and power system)
As shown in FIG. 1, a commercial power transmission line 4A from a commercial power source 4 for supplying commercial power is connected to an indoor distribution board 3 to which power supply lines 2 for a plurality of electric loads 1 are connected to serve as a power generation unit. The power transmission line 5 from the fuel cell type power generation module M is connected to the indoor distribution board 3.

In the transmission line 5 from the fuel cell power generation module M, an inverter or the like for grid interconnection that adjusts the power generated by the fuel cell power generation module M to the same voltage and frequency as the power supplied from the commercial power source 4 is installed. The power conversion unit 6 is provided.
Therefore, the commercial power from the commercial power source 4 and the power generated by the fuel cell type power generation module M are configured to be supplied to the plurality of electric loads 1.

A system casing K is provided, and the heat of the exhaust gas discharged from the above-mentioned fuel cell power generation module M, the closed hot water storage tank 8 for storing hot water, and the fuel cell power generation module M is used as exhaust heat in the system casing K. From the hot water circulation path 9 for hot water circulation connecting the bottom and the top of the hot water storage tank 8 and the bottom of the hot water storage tank 8 via the waste heat recovery heat exchange unit N to be recovered and the waste heat recovery heat exchange part N. The hot water circulation pump 10 that circulates hot water through the hot water circulation path 9, the heat storage tank J for heating that stores the latent heat storage material, and the operation control unit H are stored in the form of returning the taken out hot water to the upper part of the hot water storage tank 8. Has been done.

Further, the operation control unit H is provided with a remote controller R as an operation command unit that commands various information.

In the present embodiment, a fin tube type heat exchange type hot water supply unit D that operates with a fuel gas such as city gas and a fin tube type heat exchange type heating unit E that operates with a fuel gas such as city gas are provided. A heat source machine F is provided, and the remote control R described above is configured to command various information to the heat source control unit Fh that controls the operation of the heat source machine F.

The target is the temperature of the hot water supplied to the upper part of the hot water storage tank 8 through the hot water circulation path 9 so that the operation control unit H stores the hot water in a state where the hot water storage tank 8 is formed with a temperature stratification in the operating state of the fuel cell type power generation module M. It is configured to execute an exhaust heat recovery type hot water storage process that controls the operation of the hot water circulation pump 10 in a form of adjusting the amount of hot water circulating through the hot water circulation path 9 so as to reach a temperature (for example, 65 ° C.). There is.
By the way, the above target temperature may be automatically set to a different temperature according to the seasons such as summer, winter, and intermediate season, and the remote controller R is configured to set the user's favorite temperature. You may.

Therefore, the hot water stored in the hot water storage tank 8 is configured to be able to be discharged (hot water supply) to a hot water consumption point such as a hot water tap through a hot water outlet 11 connected to the upper part of the hot water storage tank 8.
Then, when the hot water stored in the hot water storage tank 8 is discharged, water is supplied from a water supply source such as a water supply through a water supply channel 12 connected to the lower part of the hot water storage tank 8.
That is, it is configured so that hot water can be supplied through the hot water outlet 11 connected to the upper part of the hot water storage tank 8 by the water supply pressure of the water supply channel 12 connected to the bottom of the hot water storage tank 8.

(Details of hot water circulation route)
The hot water circulation path 9 is a hot water storage outbound path 9a that connects the bottom of the hot water storage tank 8 and the exhaust heat recovery heat exchange unit N, and a hot water storage return that connects the exhaust heat recovery heat exchange unit N and the upper part of the hot water storage tank 8. It consists of road 9b.
The hot water storage outbound path 9a is provided with the hot water circulation pump 10 described above and a radiator 14 for cooling the hot water flowing in the hot water circulation path 9 along the flow direction of the hot water.
The radiator 14 has a set cooling temperature at which the temperature of the hot water flowing through the hot water storage outbound path 9a is set in a state where hot water having a target temperature (for example, 65 ° C.) is stored in the entire inside of the hot water storage tank 8 (in a boiling state). If it exceeds (for example, 40 ° C.), it is provided to cool the hot water to a set cooling temperature (for example, 40 ° C.).

The hot water storage return path 9b is provided with a hot water side sensor 17 as a temperature sensor for detecting the temperature of the hot water heated by the exhaust heat recovery heat exchange unit N.
That is, the operation control unit H is configured to control the operation of the hot water circulation pump 10 so that the detection temperature of the hot water side sensor 17 becomes the target temperature (for example, 65 ° C.) in the waste heat recovery type hot water storage process. There is.

(Details of hot water composition)
The hot water outlet 11 is provided with a mixing valve 18 that mixes hot water (cold water) supplied from the branch passage 12A branching from the water supply passage 12 and hot water (hot water) flowing through the hot water outlet 11.
Then, for example, in order to discharge hot water having a target hot water supply temperature (for example, 40 ° C.) commanded by the remote controller R, hot water (cold water) from the branch road 12A and hot water (hot water) flowing through the hot water passage 11 Is configured to be mixed by the mixing valve 18.

Further, the hot water passage 11 is configured to supply hot water to the hot water supply unit D of the heat source machine F.
Then, the hot water supply unit D heats the hot water from the hot water passage 11 to the target hot water supply temperature (for example, 40 ° C., etc.) commanded by the remote controller R, for example, when the hot water is not stored in the hot water storage tank 8. It is configured to be used for hot water.

(Details of fuel cell module)
The fuel cell type power generation module M has a cell stack 22 including a reforming processing unit 21 in which fuel gas such as city gas is supplied through a fuel gas supply path 20 and a plurality of solid oxide type fuel cell cells, and a high temperature container 23. It is configured to be stored inside the.
That is, in the present embodiment, the fuel cell type power generation module M is configured as a solid oxide fuel cell.

The reforming treatment unit 21 steam reforms the fuel gas to generate a reforming gas containing a large amount of hydrogen components, and the reforming gas produced is supplied to the cell stack 22. ing.
By the way, water vapor is supplied to the reforming processing unit 21 in addition to the fuel gas, but since the configuration is well known, detailed description thereof will be omitted in the present embodiment.

Although not shown, air (oxygen-containing gas) is supplied to the cell stack 22.
The cell stack 22 is configured to generate electricity by passing the reforming gas through the fuel electrode and passing air (oxygen-containing gas) through the oxygen electrode.

Further, the reforming gas after passing through the fuel electrode is burned by using the air (oxygen-containing gas) after passing through the oxygen electrode, and the reforming treatment unit 21 is heated by the combustion heat. It is configured.
Further, an exhaust gas passage 24 for discharging the exhaust gas obtained by burning the reformed gas from the high temperature container 23 is provided in the form of passing through the exhaust heat recovery heat exchange unit N described above. That is, the exhaust heat recovery heat exchange unit N is configured to be able to recover the exhaust heat of the exhaust gas obtained by burning the reformed gas after passing through the fuel electrode.

Further, the fuel gas supply path 20 is provided with a fuel gas supply valve 25 that opens and closes the fuel gas supply path 20 to interrupt the supply of the fuel gas, and a pressure sensor 26 that detects the supply pressure of the fuel gas. There is.
Then, when the operation control unit H determines that the fuel gas supply pressure is appropriate by the pressure sensor 26 when the operation command is commanded from the remote control R, the operation control unit H opens the fuel gas supply valve 25 and uses a fuel cell type. When the operation process for operating the power generation module M is executed and the operation stop command is commanded from the remote control R, the fuel gas supply valve 25 is closed and the stop process for stopping the fuel cell type power generation module M is executed. ..
Then, the operation control unit H is configured to execute the above-mentioned waste heat recovery type hot water storage process during the execution of the operation process.

(About the heating configuration)
Inside the heat storage tank J containing the latent heat storage material, the heating flow path 27 and the heating passage 28 are respectively from one end (lower end in the present embodiment) to the other end (the present implementation) of the heat storage tank J. In the form, it is provided so as to be located over the upper end portion).
In the present embodiment, sodium acetate trihydrate having a melting point of 58 ° C. is stored in the heat storage tank J as a latent heat storage material.

The heating circulation path 15 that circulates and supplies the heating heat medium to the heating terminal B such as the floor heating panel connects the heating return path 15a to the heating inlet 28a on one end side of the heating heated path 28. In addition, the heating outbound path 15b is provided in a state of being connected to the heating outlet 28b on the other end side of the heated path 28 for heating.
In the present embodiment, the heating pump 16 that circulates and flows the heating heat medium is arranged in the heating outbound path 15b.

The heating outbound route 15b is piped via the heating unit E of the heat source machine F.
Then, the heating unit E is configured to heat the heating heat medium flowing through the heating outbound path 15b to a target supply temperature (for example, 60 ° C., etc.) when, for example, the heat is not stored in the heat storage tank J. Has been done.
In the present embodiment, the heating pump 16 is provided in the heat source machine F.

The return side branch path 9c branched from the hot water storage return path 9b in the hot water circulation path 9 is connected to the heating inlet 27a on the other end side of the heating flow path 27, and the hot water storage outbound path in the hot water circulation path 9. The forward side merging flow path 9d that joins 9a is connected to the heating outlet 27b on one end side of the heating flow path 27, and the heat storage tank J is configured to store heat with hot water flowing through the hot water storage return path 9b. Has been done.
In the present embodiment, the outgoing side joint flow path 9d is connected to the upstream side portion of the hot water circulation pump 10 in the hot water storage outward passage 9a.

That is, when a large amount of heat is stored in the heat storage tank J, such as when the latent heat storage material is heated to the extent that it melts, the heat storage tank J uses a heating heat medium that circulates in the heating circulation path 15. When the heat is heated to the target supply temperature (for example, 60 ° C.) and the heat is not stored in the heat storage tank J, the heating heat medium is heated to the target supply temperature (for example, 60 ° C.) by the heating unit E. It is configured to heat to (° C, etc.).

(Details of heat storage configuration)
Of the hot water flowing through the hot water storage return path 9b, the amount of hot water that flows to the hot water storage outbound path 9a via the heating flow path 27 and the amount of hot water that flows to the hot water storage outbound path 9a via the hot water storage tank 8. A flow rate adjusting unit V for changing and adjusting the ratio with the amount of hot water to be stored is provided at a connection point (merging point) of the outgoing side junction flow path 9d in the hot water storage outward passage 9a.

Then, when the temperature of the hot water flowing in the forward side joint flow path 9d is equal to or lower than the set cooling temperature (for example, 40 ° C.), the flow rate adjusting unit V sets the flow rate for hot water storage to zero as shown in FIG. When the temperature of the hot water flowing through the outgoing side junction 9d exceeds the set cooling temperature (for example, 40 ° C.), as shown in FIG. 3, it is downstream from the confluence of the outgoing side junction 9d in the hot water storage outlet 9a. In order to maintain the temperature of the hot water on the side at the set cooling temperature (for example, 40 ° C.), the temperature control process for adjusting the ratio between the flow rate for heating and the flow rate for hot water storage is configured to be executed.

In the present embodiment, the flow rate adjusting unit V is configured by using a WAX type mixing valve, and when the temperature of the hot water flowing through the forward side joint flow path 9d is equal to or lower than the set cooling temperature (for example, 40 ° C.), The opening degree at which hot water flows from the outgoing side junction 9d in an attempt to raise the mixing temperature of the hot water flowing through the outgoing side junction 9d and the hot water from the bottom of the hot water storage tank 8 to the set cooling temperature (for example, 40 ° C.). Is fully opened, and the opening degree at which hot water flows from the bottom of the hot water storage tank 8 is fully closed.

Then, when the temperature of the hot water flowing in the forward side joint flow path 9d exceeds the set cooling temperature (for example, 40 ° C.), the mixed temperature of the hot water flowing in the forward side joint flow path 9d and the hot water water from the bottom of the hot water storage tank 8 is set. In an attempt to lower the temperature to the set cooling temperature (for example, 40 ° C.), the opening degree at which hot water flows from the forward side joint flow path 9d is set to the closed side rather than the fully open side, and the opening degree at which hot water flows from the bottom of the hot water storage tank 8 is set. Make it open rather than fully closed.

For example, when the temperature of the hot water flowing from the forward-side joint flow path 9d is 60 ° C. and the temperature of the hot water flowing from the bottom of the hot water storage tank 8 is 20 ° C., the ratio between the amount of hot water flowing and the amount of hot water flowing is the ratio. It becomes 1: 1 and the amount of hot water flowing from the forward side joint flow path 9d and the amount of hot water flowing from the bottom of the hot water storage tank 8 are the same.

That is, when the heat storage tank J is not stored by the operation of the flow rate adjusting unit V that executes the temperature control process, the entire amount of hot water flowing through the hot water storage return path 9b is supplied to the heat storage tank J, and the heat storage tank J The heat storage is prioritized, and as the amount of heat stored in the heat storage tank J increases, the hot water flowing through the hot water storage return path 9b is also supplied to the hot water storage tank 8 and stored. ..
Further, even if the temperature of the hot water flowing in the outbound side junction 9d changes as the amount of heat stored in the heat storage tank J changes, the downstream side of the junction of the outbound junction 9d in the hot water storage outbound passage 9a. The temperature of the hot water will be maintained at the set cooling temperature (for example, 40 ° C.).

By the way, in carrying out this embodiment, the flow rate adjusting unit V is configured by using an electric three-way valve, and when the heating operation is not performed, the entire amount of hot water flowing through the hot water storage return path 9b is used as the hot water storage tank 8. It may be configured so that it can be maintained in a state of being fluidized.

[Another Embodiment]
Next, another embodiment will be described. This other embodiment describes an embodiment in which the heat storage tank J can be used for hot water supply, and has the same configuration as that described in the above embodiment. The same reference numerals are given to the above, and detailed description thereof will be omitted.

As shown in FIG. 4, the hot water branch passage 11a branched from the hot water passage 11 is merged and connected to the outgoing side junction flow path 9d, and merges to the downstream side of the branch portion of the hot water branch passage 11a in the hot water passage 11. The hot water discharge joint flow path 11b is connected to the return side branch path 9c.
Then, a hot water discharge state switching unit W using an electric three-way valve is provided at a branch point of the hot water discharge branch path 11a in the hot water discharge path 11.
Further, a check valve 29 for preventing the backflow of hot water from the hot water storage tank 8 is provided in the flow path portion close to the hot water storage tank 8 from the branch point of the return side branch road 9c in the hot water storage return path 9b.

As shown in FIG. 5, the hot water discharge state switching unit W provides a basic hot water discharge state in which the entire amount of hot water flowing in the hot water outlet 11 is allowed to flow without branching to the hot water branch passage 11a, and a hot water outlet 11 as shown in FIG. A heat storage tank heating hot water discharge state in which the entire amount of flowing hot water is branched into a hot water outlet branch path 11a and is allowed to flow through the forward side joint flow path 9d, the heating flow path 27, the return side branch path 9c, and the hot water discharge joint flow path 11b. It is configured to switch to.

That is, when the hot water discharge state switching unit W is switched to the basic hot water discharge state, the heat storage tank J is not stored by the operation of the flow rate control unit V that executes the temperature control process, as in the previous embodiment. The entire amount of hot water flowing through the return path 9b for hot water storage is supplied to the heat storage tank J, the heat storage of the heat storage tank J is preferentially performed (see FIG. 2), and the heat storage amount of the heat storage tank J increases. As a result, the hot water flowing through the hot water storage return path 9b is stored while being supplied to the hot water storage tank 8 (see FIG. 3).
Further, even if the temperature of the hot water flowing in the outbound side junction 9d changes as the amount of heat stored in the heat storage tank J changes, the downstream side of the junction of the outbound junction 9d in the hot water storage outbound passage 9a. The temperature of the hot water will be maintained at the set cooling temperature (for example, 40 ° C.).

Then, when the amount of hot water stored in the hot water storage tank 8 becomes less than the set value (when the temperature of the hot water in the upper part of the hot water storage tank 8 becomes lower than the target temperature (for example, 65 ° C.)), as described later, the heat storage tank J When the amount of heat storage is equal to or greater than the allowable operating amount, when the hot water discharge state switching unit W is switched to the hot water discharge state heated by the heat storage tank, the entire amount of hot water flowing through the hot water outlet 11 is branched to the hot water branch passage 11a on the outgoing side. It is flowed through the joint flow path 9d, the heating flow path 27, the return side branch passage 9c, and the hot water discharge joint flow path 11b, and is heated in the heat storage tank J.

By the way, in the hot water discharge state of the heat storage tank, the hot water flowing through the return side branch passage 9c flows into the hot water passage 11 through the hot water discharge joint flow path 11b, and a part of the hot water flowing through the hot water branch passage 11a is formed. It will flow to the flow rate adjusting unit V through the forward side combined flow path 9d.
Then, the flow rate adjusting unit V adjusts the ratio of the heating flow rate and the hot water storage flow rate according to the temperature of the hot water flowing in the forward side joint flow path 9d. For example, "the upper part of the hot water storage tank 8". When the temperature of the hot water is lower than the set cooling temperature (for example, 40 ° C.) ”, as shown in FIG. 6, the temperature of the hot water flowing in the forward side joint flow path 9d is equal to or lower than the set cooling temperature (for example, 40 ° C.). At this time, the hot water flows from the forward side joint flow path 9d in an attempt to raise the mixing temperature of the hot water flowing through the forward side joint flow path 9d and the hot water from the bottom of the hot water storage tank 8 to the set cooling temperature (for example, 40 ° C.). The opening degree for flowing hot water is fully opened, and the opening degree for flowing hot water from the bottom of the hot water storage tank 8 is fully closed.

Then, in a state in which the operation control unit H normally switches the hot water discharge state switching unit W to the basic hot water discharge state and the hot water discharge state switching unit W to the basic hot water discharge state, the amount of hot water stored in the hot water storage tank 8 becomes less than the set value. When the temperature of the hot water in the upper part of the hot water storage tank 8 becomes lower than the target temperature (for example, 65 ° C.), as described later, when the heat storage amount of the heat storage tank J is equal to or more than the operation allowable amount. , The hot water discharge state switching unit W is configured to switch to the heat storage tank heating hot water discharge state.

Further, when the operation control unit H is switching to the heat storage tank heating hot water discharge state, if the heat storage amount of the heat storage tank J is equal to or less than the operation stop amount described later, the hot water discharge state switching unit W is switched to the basic hot water discharge state. It is configured in.

The other end side temperature sensor Tu that detects the other end side temperature (upper end side temperature) inside the heat storage tank J and the one end side that detects the one end side temperature (lower end side temperature) inside the heat storage tank J Temperature sensors Ts are provided.
Then, the operation control unit H detects a set high temperature side temperature (for example, 65 ° C.) at which the other end side temperature sensor Tu and the one end side temperature sensor Ts are higher than the melting point (for example, 58 ° C.) of the latent heat storage material. Then, when it is determined that the amount of heat stored in the heat storage tank J is equal to or greater than the allowable operating amount, and the temperature sensor Ts on one end detects a set low temperature side temperature (for example, 50 ° C.) lower than the melting point of the latent heat storage material, heat storage is performed. It is configured to determine that the heat storage amount of the tank J is equal to or less than the operation stop amount.

A hot water temperature sensor S for detecting the temperature of the hot water stored in the hot water storage tank 8 is provided on the upper end side of the hot water storage tank 8.
Then, the operation control unit H is configured to determine that the amount of hot water stored in the hot water storage tank 8 is less than the set value when the detected temperature of the hot water temperature sensor S becomes lower than the target temperature (for example, 65 ° C.). ing.

[Other Other Embodiments]
Next, other other embodiments are listed.
(1) In the above embodiment and another embodiment, the fuel cell type power generation module M is exemplified as the power generation unit, but the power generation unit may be provided with a gas engine for driving the generator.
In this case, the exhaust heat recovery heat exchange unit N recovers the heat when cooling the gas engine.

(2) In the above embodiment, the fuel cell type power generation module M provided with the solid oxide type fuel cell is exemplified as the fuel cell type power generation unit, but the fuel cell type power generation unit is a solid polymer type. This may be carried out in the form of providing a fuel cell type power generation unit including the fuel cell of the above.
In this case, the exhaust heat recovery heat exchange unit N recovers the heat when cooling the fuel cell type power generation unit.

(3) In the above embodiment and another embodiment, the case where the flow rate adjusting unit V is configured by using a three-way valve is illustrated, but the flow rate adjusting valve that adjusts the flow rate of hot water flowing through the forward side joint flow path 9d. A specific flow rate adjusting unit V, such as forming a flow rate adjusting unit V by a flow rate adjusting valve that adjusts the flow rate of hot water from the bottom of the hot water storage tank 8 and a valve control unit that controls those flow rate adjusting valves. The configuration can be changed in various ways.

(4) In the above embodiment and another embodiment, the case where the heat storage tank J is installed in the vertical posture is illustrated, but the specific embodiment of the installation of the heat storage tank J, such as installing the heat storage tank J in the sideways posture, is Various changes can be made.

(5) In the above embodiment and another embodiment, sodium acetate trihydrate was exemplified as the latent heat storage material, but as the latent heat storage material, paraffin-based triactan (melting point 65 ° C.) and organic stearic acid were used. Various things such as (melting point 71 ° C.) can be applied.

(6) In the above embodiment and another embodiment, the radiator 14 for cooling the hot water flowing in the hot water circulation path 9 is provided in the hot water storage outbound path 9a of the hot water circulation path 9, but the radiator 14 is omitted. It may be carried out in the form of.

The configurations disclosed in the above embodiment (including another embodiment) can be applied in combination with the configurations disclosed in other embodiments as long as there is no contradiction, and the present specification. The embodiment disclosed in the above is an example, and the embodiment of the present invention is not limited to this, and can be appropriately modified without departing from the object of the present invention.

8 Hot water storage tank 9 Hot water circulation path 9a Outward path for hot water storage 9b Return path for hot water storage 9c Return side branch path 9d Outgoing side joint flow path 10 Hot water circulation pump 11 Hot water circulation pump 11 Outlet channel 11a Hot water branch path 11b Hot water supply junction 12 Water supply channel 15 For heating Circulation path 15a Return path for heating 27 Flow path for heating 27a Inlet for heating 27b Outlet for heating 28 Pass for heating 28a Inlet for heating 28b Outlet for heating H Operation control unit J Heat storage tank M Power generation unit N Exhaust heat recovery heat exchange Part Ts One end side temperature sensor Tu The other end side temperature sensor V Flow control part W Hot water discharge state switching part

Claims (5)

The bottom and top of the hot water storage tank are via a power generation unit that operates by supplying fuel, a closed hot water storage tank that stores hot water, and an exhaust heat recovery heat exchange unit that recovers the exhaust heat of the power generation unit. A hot water circulation pump for circulating hot water through the hot water circulation path, and an operation control unit in a form of returning the hot water taken out from the bottom of the hot water storage tank to the upper part of the hot water storage tank. Is provided,
In order for the operation control unit to store hot water in a state where a temperature stratification is formed in the hot water storage tank in the operating state of the power generation unit, the temperature of hot water supplied to the upper part of the hot water storage tank through the hot water circulation path becomes the target temperature. It is a combined heat and power system configured to execute an exhaust heat recovery type hot water storage process that controls the operation of the hot water circulation pump in a form of adjusting the amount of hot water circulating through the hot water circulation path.
Inside the heat storage tank containing the latent heat storage material, each of the heating flow path and the heated passage for heating is provided so as to be located from one end to the other end of the heat storage tank.
The heating circulation path that circulates and supplies the heating heat medium to the heating terminal connects the heating return path to the heating inlet on one end side of the heating heated path, and connects the heating outbound path to the heating. It is provided in a state of being connected to the heating outlet on the other end side of the heated passage.
The return side branch path branched from the hot water storage return path connecting the exhaust heat recovery heat exchange section and the upper part of the hot water storage tank in the hot water circulation path serves as a heating inlet on the other end side of the heating flow path. The forward side junction flow path that is connected and joins the hot water storage outbound path that connects the bottom of the hot water storage tank and the exhaust heat recovery heat exchange section in the hot water circulation path is on one end side of the heating flow path. Connected to the heating outlet,
Of the hot water flowing through the hot water storage return path, the amount of hot water that flows to the hot water storage outbound path via the heating flow path and the amount of hot water that flows to the hot water storage outbound path via the hot water storage tank. When the temperature of the hot water flowing in the forward side joint flow path is equal to or lower than the set cooling temperature, the flow rate adjusting unit for changing and adjusting the ratio with the flow rate for hot water storage makes the flow rate for hot water storage zero. When the temperature of the hot water flowing through the outgoing side junction flow path exceeds the set cooling temperature, the temperature of the hot water water downstream from the confluence of the outgoing side junction flow path in the hot water storage outbound passage is maintained at the set cooling temperature. Therefore, a combined heat and power supply system configured to execute a temperature control process for adjusting the ratio between the flow rate for heating and the flow rate for hot water storage. It is configured so that hot water can be supplied through the hot water outlet connected to the upper part of the hot water storage tank by the water supply pressure of the water supply channel connected to the bottom of the hot water storage tank.
The hot water outlet branch path branched from the hot water outlet is connected to the outgoing hot water branch flow path and joins the hot water discharge branch path downstream of the branch point of the hot water branch path in the hot water outlet. Connected to the return branch,
The basic hot water state in which the entire amount of hot water flowing in the hot water passage is flowed without branching to the hot water branch path, and the total amount of hot water flowing in the hot water channel is branched into the hot water branch path to the outgoing side. The combined heat and power supply according to claim 1, wherein the combined flow path, the heating flow path, the return side branch path, and a hot water discharge state switching unit for switching between the hot water discharge state of the heat storage tank flowing through the hot water discharge joint flow path are provided. system. When the operation control unit switches the hot water discharge state switching unit to the basic hot water discharge state, and the heat storage amount of the hot water storage tank becomes less than the set value, the heat storage amount of the heat storage tank is equal to or more than the operation allowable amount. The combined heat and power system according to claim 2, wherein the hot water discharge state switching unit is configured to switch to the hot water discharge state heated by the heat storage tank. When the operation control unit is switched to the heat storage tank heating hot water discharge state, if the heat storage amount of the heat storage tank is equal to or less than the operation stop amount, the hot water discharge state switching unit is configured to switch to the basic hot water discharge state. The combined heat and power system according to claim 3. An other end side temperature sensor for detecting the temperature on the other end side inside the heat storage tank and a one end side temperature sensor for detecting the temperature on the one end side inside the heat storage tank are provided.
When the operation control unit detects a set high temperature side temperature higher than the melting point of the latent heat storage material by each of the other end side temperature sensor and the one end side temperature sensor, the heat storage amount of the heat storage tank is the operation permit. When it is determined that the capacity is equal to or higher than the capacity and the one end side temperature sensor detects a set low temperature side temperature lower than the melting point of the latent heat storage material, it is determined that the heat storage amount of the heat storage tank is equal to or less than the operation stop amount. The combined heat and power supply system according to claim 4, which is configured to perform the same.

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