JP2012156040A - Hybrid power generating system - Google Patents

Abstract

A hybrid power generation system having a simple configuration, high power generation efficiency, and excellent energy saving and reliability is provided.
A fuel cell, a solar cell panel, a hot water storage tank, a hot water storage tank, a panel heat exchanger for cooling the solar cell panel, and a waste heat of the fuel cell are recovered. A heat recovery path in which the heat recovery heat exchanger 4 is sequentially connected in an annular manner by a heat recovery pipe, a bypass path that bypasses the panel heat exchanger 32 in the heat recovery path, and a panel switching that switches water flow to the bypass path Means 34 and 36 are provided. Thereby, since the solar cell panel 31 is cooled using the water in the hot water storage tank 1, an increase in the surface temperature of the solar cell panel 31 can be suppressed even in summer and the like, so that the power generation efficiency by sunlight is improved. be able to. Further, by collecting solar heat and heating the water in the hot water storage tank 1, it is possible to secure a sufficient amount of heat for the hot water supply load at home.
[Selection] Figure 1

Description

  The present invention relates to a hybrid power generation system that generates electric power using a fuel cell and a solar cell, and generates hot water by recovering and utilizing the exhaust heat.

  In recent years, fuel cells that generate electrical energy by direct reaction of hydrogen and oxygen are expected to be clean power generators because they have high power generation efficiency and emit almost no air pollutants. In particular, a fuel cell cogeneration system that collects and uses exhaust heat generated during power generation of a fuel cell has high overall energy efficiency and is expected to spread as an energy saving device. As a method for recovering and utilizing the exhaust heat of the fuel cell, it is common to use the heat exchanger for heat recovery to heat the water in the hot water storage tank and use it as hot water.

  On the other hand, solar power generation systems that directly generate electrical energy from sunlight using photoelectric conversion using solar cells are also becoming popular as clean power generators that do not emit carbon dioxide, mainly for home use.

  It has been proposed that both such a solar power generation system and a fuel cell cogeneration system are installed in a home and used in combination as a hybrid power generation system with higher energy savings (see, for example, Patent Document 1). . In this case, solar power generation was mainly used for power supply during the day, and the fuel cell was obtained by recovering the exhaust heat of the fuel cell in addition to supplementing the solar cell during the day and supplying power during the night. Hot water is often used for hot water supply, bathing, and heating.

  As shown in FIG. 7, the conventional hybrid power generation system includes, for example, a solar cell panel 31, a fuel cell 7 that houses the fuel cell 7, and a heat recovery heat exchanger 4, and a hot water storage unit 22 that houses the hot water storage tank 1. Composed. In general, the power obtained by the power generation of the solar cell panel 31 and the fuel cell 7 is boosted, rectified, and converted from direct current to alternating current in the power conversion device 24, and supplied as household power.

  Further, in the hybrid power generation system, as shown in FIG. 7, the heat recovery tank 1, the hot water circulation pump 2, and the heat recovery heat exchanger 4 are sequentially connected in an annular manner through the heat recovery pipe 3, thereby recovering heat. A path is formed. On the other hand, a cooling water path is formed by sequentially connecting the fuel cell 7, the cooling water circulation pump 5, and the heat recovery heat exchanger 4 in an annular manner by the cooling water pipe 6.

  The exhaust heat generated when the fuel cell 7 generates power is recovered in the cooling water. The cooling water is conveyed to the heat recovery heat exchanger 4 by the cooling water circulation pump 5, where water from the hot water storage tank 1 is heated. The water in the hot water storage tank 1 circulates in the heat recovery path 8 by the hot water storage circulation pump 2, is heated by the cooling water of the fuel cell 7 in the heat recovery heat exchanger 4, and is stored in the hot water storage tank 1 again.

The hybrid power generation system uses a water supply inlet pipe 9, a pressure reducing valve 10, a first water supply pipe 11, a second water supply pipe 12, and a hot water pipe to supply water to the hot water storage tank 1 and to supply hot water from the hot water storage tank 1 to the outside. 13, a mixing valve 14 and a hot water supply outlet pipe 15 are provided. Water supply to the hot water storage tank 1 is performed via a pressure reducing valve 10 and a first water supply pipe 11 from a water supply inlet pipe 9 connected to a general water supply pipe. Hot water from the hot water storage tank 1 was discharged from the water supplied via the water supply inlet pipe 9, the pressure reducing valve 10, and the second water supply pipe 12 and from the upper part of the hot water storage tank 1 via the hot water discharge pipe 13. Hot water is mixed at an appropriate temperature by the mixing valve 14 and supplied to the outside through the hot water supply outlet pipe 15.

JP 2002-34161 A

  However, in the above-described conventional configuration, for example, in summer, the surface temperature of the solar cell panel increases, so that there is a problem in that the energy conversion efficiency from light to electricity of the solar cell element decreases and energy saving performance decreases. In addition, because hot water is generated only with the exhaust heat of the fuel cell, if the usage rate of solar power generation is high with respect to fuel cell power generation, there is a possibility that a sufficient amount of hot water cannot be secured for the hot water supply load at home. There was a problem.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a hybrid power generation system that has a simple configuration, high power generation efficiency, and excellent energy saving and reliability.

  In order to solve the above conventional problems, a hybrid power generation system of the present invention includes a fuel cell, a solar cell panel, a hot water storage tank, a hot water storage tank, a panel heat exchanger for cooling the solar cell panel, and a fuel. A heat recovery path in which a heat recovery heat exchanger that recovers the exhaust heat of the battery is sequentially connected in an annular manner by a heat recovery pipe, a bypass path that bypasses the panel heat exchanger in the heat recovery path, and a connection to the bypass path It has the structure which provided the switching means which switches water.

  Thus, by cooling the solar cell panel using the water in the hot water storage tank, it is possible to suppress an increase in the surface temperature of the solar cell panel even in summer and the like, so that the power generation efficiency by sunlight can be improved. it can. Further, by collecting solar heat and heating the water in the hot water storage tank, it is possible to secure a sufficient amount of heat for the hot water supply load at home. Therefore, it is possible to realize a hybrid power generation system with a simple configuration, high power generation efficiency, and excellent energy saving and reliability.

  According to the present invention, it is possible to realize a hybrid power generation system having a simple configuration and excellent in energy saving and reliability.

Configuration diagram of hybrid power generation system in Embodiment 1 of the present invention Configuration diagram of hybrid power generation system in Embodiment 2 of the present invention Configuration diagram of hybrid power generation system in Embodiment 3 of the present invention Configuration diagram of hybrid power generation system in Embodiment 4 of the present invention Configuration diagram of hybrid power generation system in Embodiment 5 of the present invention Configuration diagram of hybrid power generation system in Embodiment 6 of the present invention Configuration diagram of conventional fuel cell cogeneration system

1st invention is a hybrid electric power generation system provided with the fuel cell, the solar cell panel, and the hot water storage tank, Comprising: The hot water storage tank, the panel heat exchanger which cools a solar cell panel, and the exhaust heat of a fuel cell are collect | recovered A heat recovery path in which the heat recovery heat exchanger is sequentially connected in an annular manner by a heat recovery pipe, a bypass path that bypasses the panel heat exchanger to the heat recovery path, and a switching means that switches water flow to the bypass path. The configuration is provided. Thus, by cooling the solar cell panel using the water in the hot water storage tank, it is possible to suppress an increase in the surface temperature of the solar cell panel even in summer and the like, so that the power generation efficiency by sunlight can be improved. it can. Further, by collecting solar heat and heating the water in the hot water storage tank, it is possible to secure a sufficient amount of heat for the hot water supply load at home. Therefore, it is possible to realize a hybrid power generation system with a simple configuration, high power generation efficiency, and excellent energy saving and reliability.

  According to a second invention, in the first invention, the amount of generated power of the solar cell panel is detected, and when the detected amount of generated power is smaller than a predetermined value, the panel heat exchanger is switched to a bypass path. is there. As a result, when it is determined that the amount of power generated by the solar panel is small and solar heat cannot be effectively recovered and used, such as during winter and nighttime, when the amount of sunlight is small, the heat recovery path should be connected to the panel heat exchanger. By switching only to the bypass path on the fuel cell side, the pump power necessary for circulating hot water can be suppressed, the power consumption of the system can be reduced, and further energy saving can be achieved.

  According to a third invention, in the first invention, the surface temperature of the solar battery panel is detected, and when the detected surface temperature is lower than a predetermined value, the panel heat exchanger is switched to a bypass path. As a result, when it is determined that the solar panel surface temperature is low and solar heat cannot be effectively recovered and used, such as in winter and at night, when the amount of sunlight is low, bypass the panel heat exchanger for the heat recovery path. By switching only to the path on the fuel cell side, the pump power necessary for circulating hot water can be suppressed, the power consumption of the system can be reduced, and further energy saving can be achieved.

  According to a fourth invention, in the first invention, the water temperature at the inlet and outlet of the panel heat exchanger is detected, and when the detected temperature difference is smaller than a predetermined value, the panel heat exchanger is switched to a bypass path. Is. Thereby, it can be judged easily whether solar heat can be used effectively by comparing the water temperature of the entrance / exit of a panel heat exchanger. If it is determined that solar heat cannot be used effectively, the heat recovery path is switched to only the path on the fuel cell side that bypasses the panel heat exchanger, thereby suppressing the pump power required for circulating hot water. In addition, the power consumption of the system can be reduced, and further energy saving can be achieved.

  According to a fifth invention, in the first invention, there is provided a mixing valve for adjusting the hot water after heat recovery from the panel heat exchanger and the water from the hot water storage tank to a predetermined temperature, and flows into the heat recovery heat exchanger. The temperature of water is controlled below a predetermined temperature. As a result, the temperature of the hot water storage required for cooling the fuel cell can be secured, and the operation of solar power generation and fuel cell power generation can be easily made compatible, so that energy saving and improvement in reliability can be achieved. it can.

  A sixth invention includes a fuel cell, a solar cell panel, and a hot water storage tank, a hot water storage tank, a panel heat exchanger that cools the solar cell panel, and a heat recovery heat exchange that recovers exhaust heat of the fuel cell. A heat recovery path in which the heat exchanger pipes are successively connected in an annular manner by a heat recovery pipe, a bypass path that bypasses the heat recovery heat exchanger in the heat recovery path, and a switching means that switches water flow to the bypass path. Have. Thus, by cooling the solar cell panel using the water in the hot water storage tank, it is possible to suppress an increase in the surface temperature of the solar cell panel even in summer and the like, so that the power generation efficiency by sunlight can be improved. it can. Further, by collecting solar heat and heating the water in the hot water storage tank, it is possible to secure a sufficient amount of heat for the hot water supply load at home. Furthermore, when power generation by the fuel cell is stopped, inflow to the heat exchanger for heat recovery is avoided, energy loss due to heat dissipation of hot water and pump power necessary for circulating hot water can be suppressed. it can. Therefore, it is possible to realize a hybrid power generation system with a simple configuration, high power generation efficiency, and excellent energy saving and reliability.

According to a seventh aspect, in the sixth aspect, the outlet water temperature of the panel heat exchanger is detected, and when the temperature is higher than a predetermined value, the path is switched to a path that bypasses the heat recovery heat exchanger.
When the outside air temperature is high and the amount of solar radiation is large as in the daytime in summer, the amount of heat recovered by the panel heat exchanger is increased, and the outlet temperature of the panel heat exchanger can be secured at a high temperature. On the other hand, when the temperature of the hot water storage becomes high, the temperature necessary for cooling the fuel cell cannot be secured. Thus, when it is determined that the fuel cell cannot be sufficiently cooled, the heat recovery path is switched to a path on the solar cell panel side that bypasses the heat exchanger for heat recovery. As a result, stable operation of the system can be maintained, pump power necessary for circulating hot water can be suppressed, and power consumption of the system can be reduced, so that further energy saving can be achieved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the same reference numerals are given to the same configurations as the conventional configurations described above, and the detailed description thereof will be omitted. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram of a hybrid power generation system according to Embodiment 1 of the present invention.

  As shown in FIG. 1, the hybrid power generation system of the present embodiment includes a solar cell panel 31, a fuel cell unit 21 that houses a fuel cell 7 and a heat recovery heat exchanger 4, and a hot water storage that houses a hot water storage tank 1. The unit 22 and the power conversion device 24 are included.

  The hot water storage tank 1, the hot water circulation pump 2, the panel heat exchanger 32 that cools the solar battery panel 31, and the heat recovery heat exchanger 4 that recovers exhaust heat during power generation of the fuel cell 7 are heated. A heat recovery path that is successively connected in an annular shape by the recovery pipe 3 is formed. The panel heat exchanger 32 is provided, for example, on the back surface of the solar cell panel 31 and has a configuration in which a pipe line through which hot water is stored is in close contact with the solar cell panel 31 so that the entire solar cell panel 31 or a part thereof can be cooled. It is a heat exchanger which has. In addition, a cooling water path is formed by sequentially connecting the fuel cell 7, the cooling water circulation pump 5, and the heat recovery heat exchanger 4 in an annular manner by the cooling water pipe 6.

  On the other hand, the electric power obtained by the power generation of the solar cell panel 31 and the fuel cell 7 is boosted, rectified, and converted from direct current to alternating current in the power conversion device 24, and used as household power.

  The water in the lower part of the hot water storage tank 1 is circulated in the heat recovery path by the hot water storage circulation pump 2, heated by the solar heat of the solar cell panel 31 by the panel heat exchanger 32, and further heated by the heat recovery heat exchanger 4 of the fuel cell 7. It is heated by cooling water or the like that has absorbed the exhaust heat, and returns to the upper part of the hot water storage tank 1 as hot water. The exhaust heat generated along with the power generation in the fuel cell 7 is recovered into the cooling water in the cooling water path, and is transferred to the heat recovery heat exchanger 4 by the cooling water circulation pump 5 to heat the water from the hot water storage tank 1.

  In addition, in order to supply water to the hot water storage tank 1 or to supply hot water from the hot water storage tank 1 to the outside, the water supply inlet pipe 9, the pressure reducing valve 10, the first water supply pipe 11, the second water supply pipe 12, the hot water supply pipe 13, and the mixing valve 14 are used. The hot water supply outlet pipe 15 is provided. Water supply to the hot water storage tank 1 is performed via a pressure reducing valve 10 and a first water supply pipe 11 from a water supply inlet pipe 9 connected to a general water supply pipe. Hot water from the hot water storage tank 1 was discharged from the water supplied via the water supply inlet pipe 9, the pressure reducing valve 10, and the second water supply pipe 12 and from the upper part of the hot water storage tank 1 via the hot water discharge pipe 13. Hot water is mixed at an appropriate temperature by the mixing valve 14 and supplied to the outside through the hot water supply outlet pipe 15.

Here, in the hybrid power generation system of the present embodiment, a bypass pipe 35 that bypasses the panel heat exchanger 32 is provided in the middle of the heat recovery path, and further, water is passed to the panel heat exchanger 32 and the bypass path. Panel switching means 34 and bypass switching means 36 for switching are provided. Each of the panel switching means 34 and the bypass switching means 36 is constituted by, for example, an electromagnetic valve. During normal power generation, the panel switching means 34 is opened and the bypass switching means 36 is closed. In addition, the power conversion device 24 is provided with a wattmeter 25 that detects the amount of power generated by the solar battery panel 31.

  In general, when the surface temperature of a solar cell increases, the power generation efficiency decreases. In particular, as in the summer, when the amount of solar radiation is large and the outside air temperature is high, the power generation efficiency tends to decrease. During the daytime in the summer, the power load due to the use of cooling is large, so the most amount of power is required throughout the year. In such a period, a decrease in the power generation efficiency of the system is not preferable in order to ensure energy saving.

  According to the present embodiment, by using the water in the hot water storage tank 1 to cool the solar cell panel 31 via the panel heat exchanger 32, the increase in the surface temperature of the solar cell panel 31 is suppressed, and sunlight This can improve the power generation efficiency.

  On the other hand, according to the present embodiment, the panel heat exchanger 32 can recover the heat of the solar cell panel 31 and heat the water in the hot water storage tank 1. That is, as a heat source for hot water storage in the hot water storage tank 1, not only exhaust heat of the fuel cell 7 but also solar heat can be utilized through the panel heat exchanger 32. According to this, it becomes possible to ensure a sufficient amount of heat for the hot water supply load at home. Therefore, it is possible to realize a hybrid power generation system having a simple configuration with high power generation efficiency and excellent energy saving and reliability.

  Further, when the amount of power generated by the solar battery panel 31 detected by the wattmeter 25 is smaller than a predetermined value, the panel switching means 34 is closed and the bypass switching means 36 is opened, so that the path of the hot water storage panel can be opened. Switch to the bypass path of the heat exchanger 32. When the amount of sunshine is low, such as at night or during rainy or cloudy weather, the amount of power generated by sunlight is extremely small. When it is judged that such solar power generation and thus hot water storage by solar heat cannot be used sufficiently effectively, the heat recovery path is switched to a path bypassing the panel heat exchanger 32 and only the exhaust heat of the fuel cell 7 is used. Switch to the route to be used. By carrying out like this, the motive power of the hot water circulating pump 2 required for the circulating hot water can be suppressed. That is, the power consumption of the system can be reduced, and further energy saving can be achieved.

  As described above, according to the present embodiment, it is possible to provide a hybrid power generation system that has a simple configuration, high power generation efficiency, and excellent energy saving and reliability.

(Embodiment 2)
FIG. 2 is a configuration diagram of a hybrid power generation system according to Embodiment 2 of the present invention.

  As shown in FIG. 2, the hybrid power generation system of the present embodiment includes surface temperature detection means 26 that detects the surface temperature of the solar cell panel 31, and when the surface temperature of the solar cell panel 31 is lower than a predetermined value. The hot water path differs from the first embodiment in that the hot water path is switched to a path that bypasses the panel heat exchanger 32. The configuration and operation of the hybrid power generation system according to the present embodiment are substantially the same as those described in the first embodiment, and thus detailed description thereof is omitted here.

When the surface temperature of the solar cell panel 31 is relatively low, no significant reduction in power generation efficiency is observed. Moreover, the amount of solar heat recovered by the panel heat exchanger 32 is also limited. In particular, when the outside air temperature in winter is low, it may be assumed that the stored hot water from the hot water storage tank 1 is dissipated and cooled instead. In the present embodiment, when the surface temperature of the solar battery panel 31 is lower than a predetermined value, for example, when it is determined that sunlight and solar heat cannot be effectively recovered and used, such as in winter or at night, when the amount of sunlight is small. Switches the heat recovery path to a path that bypasses the panel heat exchanger 32;
The route is switched to a route that uses only the exhaust heat of the fuel cell 7. By carrying out like this, the motive power of the hot water circulating pump 2 required for the circulating hot water can be suppressed. Therefore, the power consumption of the system can be reduced, and further energy saving can be achieved.

(Embodiment 3)
FIG. 3 is a configuration diagram of a hybrid power generation system according to Embodiment 3 of the present invention.

  As shown in FIG. 3, the hybrid power generation system of the present embodiment includes a heat exchange inlet temperature detection means 27 and a heat exchange outlet temperature detection means 28 that detect the water temperatures of the inlet and outlet of the panel heat exchanger 32, and these When the difference in temperature detected in step S is smaller than a predetermined value, the hot water path is different from that of the first embodiment in that the hot water path is switched to a path that bypasses the panel heat exchanger 32. The configuration and operation of the hybrid power generation system according to the present embodiment are substantially the same as those described in the first embodiment, and thus detailed description thereof is omitted here.

  By comparing the water temperatures at the entrance and exit of the panel heat exchanger 32, it is possible to easily determine whether the panel heat exchanger 32 has sufficiently recovered solar heat. If it is judged that solar heat cannot be used effectively, the heat recovery path is switched to only the path on the fuel cell 7 side that bypasses the panel heat exchanger 32, so that the hot water circulation necessary for the circulation of the hot water is performed. The power of the pump 2 can be suppressed. Therefore, the power consumption of the system can be reduced, and further energy saving can be achieved.

(Embodiment 4)
FIG. 4 is a configuration diagram of a hybrid power generation system according to Embodiment 4 of the present invention.

  As shown in FIG. 4, the hybrid power generation system according to the present embodiment is provided with a feed water temperature detecting means 38 for detecting the water temperature flowing into the heat recovery heat exchanger 4 and after recovering heat from the panel heat exchanger 32. The mixing valve 37 for adjusting the hot water and the water from the hot water storage tank 1 to a predetermined temperature is provided, and the temperature of the water flowing into the heat recovery heat exchanger 4 is controlled to be equal to or lower than the predetermined temperature. This is different from the first form. The configuration and operation of the hybrid power generation system according to the present embodiment are substantially the same as those described in the first embodiment, and thus detailed description thereof is omitted here.

  In order to ensure stable power generation performance in the fuel cell 7, it is necessary to maintain the fuel cell 7 at a constant temperature with cooling water. According to the present embodiment, the water from the hot water storage tank 1 is mixed with the hot water heated by the panel heat exchanger 32 using the mixing valve 37, and the water temperature flowing into the heat recovery heat exchanger 4 is kept constant. The temperature can be adjusted. Therefore, the temperature of the hot water storage required for cooling the fuel cell 7 can be secured, and the operation of solar power generation and fuel cell power generation can be easily made compatible, thereby improving the energy saving and reliability of the system. Can be planned.

(Embodiment 5)
FIG. 5 is a configuration diagram of a hybrid power generation system according to Embodiment 5 of the present invention.

  As shown in FIG. 5, the hybrid power generation system of the present embodiment includes a solar cell panel 31, a fuel cell unit 21 that houses the fuel cell 7 and the heat recovery heat exchanger 4, and a hot water storage that houses the hot water storage tank 1. The unit 22 and the power conversion device 24 are included.

The hot water storage tank 1, the hot water circulation pump 2, the panel heat exchanger 32 that cools the solar battery panel 31, and the heat recovery heat exchanger 4 that recovers exhaust heat during power generation of the fuel cell 7 are heated. A heat recovery path that is successively connected in an annular shape by the recovery pipe 3 is formed. The panel heat exchanger 32 is provided, for example, on the back surface of the solar cell panel 31 and has a configuration in which a pipe line through which hot water is stored is in close contact with the solar cell panel 31 so that the entire solar cell panel 31 or a part thereof can be cooled. It is a heat exchanger which has. In addition, a cooling water path is formed by sequentially connecting the fuel cell 7, the cooling water circulation pump 5, and the heat recovery heat exchanger 4 in an annular manner by the cooling water pipe 6.

  On the other hand, the electric power obtained by the power generation of the solar cell panel 31 and the fuel cell 7 is boosted, rectified, and converted from direct current to alternating current in the power conversion device 24, and used as household power.

  The water in the lower part of the hot water storage tank 1 is circulated in the heat recovery path by the hot water storage circulation pump 2, heated by the solar heat of the solar cell panel 31 by the panel heat exchanger 32, and further heated by the heat recovery heat exchanger 4 of the fuel cell 7. It is heated by cooling water or the like that has absorbed the exhaust heat, and returns to the upper part of the hot water storage tank 1 as hot water. The exhaust heat generated along with the power generation in the fuel cell 7 is recovered into the cooling water in the cooling water path, and is transferred to the heat recovery heat exchanger 4 by the cooling water circulation pump 5 to heat the water from the hot water storage tank 1.

  In addition, in order to supply water to the hot water storage tank 1 or to supply hot water from the hot water storage tank 1 to the outside, the water supply inlet pipe 9, the pressure reducing valve 10, the first water supply pipe 11, the second water supply pipe 12, the hot water supply pipe 13, and the mixing valve 14 are used. The hot water supply outlet pipe 15 is provided. Water supply to the hot water storage tank 1 is performed via a pressure reducing valve 10 and a first water supply pipe 11 from a water supply inlet pipe 9 connected to a general water supply pipe. Hot water from the hot water storage tank 1 was discharged from the water supplied via the water supply inlet pipe 9, the pressure reducing valve 10, and the second water supply pipe 12 and from the upper part of the hot water storage tank 1 via the hot water discharge pipe 13. Hot water is mixed at an appropriate temperature by the mixing valve 14 and supplied to the outside through the hot water supply outlet pipe 15.

  Here, in the hybrid power generation system of the present embodiment, a bypass path 41 that bypasses the heat recovery heat exchanger 4 is provided in the middle of the heat recovery path, and further, the heat recovery heat exchanger 4 and the bypass path 41. The heat exchanger switching means 42 and the bypass switching means 43 which switch water flow to are provided. Each of the heat exchanger switching means 42 and the bypass switching means 43 is constituted by, for example, an electromagnetic valve, and during normal power generation, the heat exchanger switching means 42 is opened and the bypass switching means 43 is closed. Further, on the outlet side of the panel heat exchanger 32, heat exchange outlet temperature detecting means 44 for detecting the temperature of the hot water storage is provided.

  In general, when the surface temperature of a solar cell increases, the power generation efficiency decreases. In particular, as in the summer, when the amount of solar radiation is large and the outside air temperature is high, the power generation efficiency tends to decrease. During the daytime in the summer, the power load due to the use of cooling is large, so the most amount of power is required throughout the year. In such a period, a decrease in the power generation efficiency of the system is not preferable in order to ensure energy saving.

  According to the present embodiment, by using the water in the hot water storage tank 1 to cool the solar cell panel 31 via the panel heat exchanger 32, the increase in the surface temperature of the solar cell panel 31 is suppressed, and sunlight This can improve the power generation efficiency.

  On the other hand, according to the present embodiment, the panel heat exchanger 32 can recover the heat of the solar cell panel 31 and heat the water in the hot water storage tank 1. That is, as a heat source for hot water storage in the hot water storage tank 1, not only exhaust heat of the fuel cell 7 but also solar heat can be utilized through the panel heat exchanger 32. According to this, it becomes possible to ensure a sufficient amount of heat for the hot water supply load at home. Therefore, it is possible to realize a hybrid power generation system having a simple configuration with high power generation efficiency and excellent energy saving and reliability.

Further, according to the present embodiment, in the case where the power generation by the fuel cell 7 is stopped, it is possible to avoid the flow of hot hot water into the heat recovery heat exchanger 4. According to this, it is possible to avoid a heat dissipation loss that occurs when hot hot water flows through the heat recovery heat exchanger 4 at room temperature. Moreover, the pump power required for the circulation of hot water storage can be suppressed.

  Furthermore, the outlet water temperature of the panel heat exchanger 32 is detected, and when the temperature is higher than a predetermined value, the temperature is switched to a path 41 that bypasses the heat recovery heat exchanger 4. When the outside air temperature is high and the amount of solar radiation is large as in the daytime in summer, the amount of heat recovered by the panel heat exchanger 32 is increased, and the outlet temperature of the panel heat exchanger 32 can be kept high. On the other hand, when the temperature of the hot water storage becomes high, the temperature necessary for cooling the fuel cell 7 cannot be secured. As described above, when it is determined that the fuel cell 7 cannot be sufficiently cooled, the heat recovery path is switched to a path that bypasses the heat recovery heat exchanger 4. As a result, stable operation of the system can be maintained, pump power necessary for circulating hot water can be suppressed, and power consumption of the system can be reduced, so that further energy saving can be achieved.

  As described above, according to the present embodiment, it is possible to provide a hybrid power generation system that has a simple configuration, high power generation efficiency, and excellent energy saving and reliability.

(Embodiment 6)
FIG. 6 is a configuration diagram of a hybrid power generation system according to Embodiment 6 of the present invention.

  As shown in FIG. 6, the hybrid power generation system of the present embodiment includes a solar cell panel 31, a fuel cell unit 21 that houses the fuel cell 7 and the heat recovery heat exchanger 4, and a hot water storage that houses the hot water storage tank 1. The unit 22 and the power conversion device 24 are included.

  The hot water storage tank 1, the hot water circulation pump 2, the panel heat exchanger 32 that cools the solar battery panel 31, and the heat recovery heat exchanger 4 that recovers exhaust heat during power generation of the fuel cell 7 are heated. A heat recovery path that is successively connected in an annular shape by a recovery pipe is formed. The panel heat exchanger 32 is provided, for example, on the back surface of the solar cell panel 31 and has a configuration in which a pipe line through which hot water is stored is in close contact with the solar cell panel 31 so that the entire solar cell panel 31 or a part thereof can be cooled. It is a heat exchanger which has. Further, the cooling water path is formed by sequentially connecting the fuel cell 7, the cooling water circulation pump 5, and the heat recovery heat exchanger 4 in an annular manner with cooling water piping.

  On the other hand, the electric power obtained by the power generation of the solar cell panel 31 and the fuel cell 7 is boosted, rectified, and converted from direct current to alternating current in the power conversion device 24, and used as household power.

  The water in the lower part of the hot water storage tank 1 is circulated in the heat recovery path by the hot water storage circulation pump 2, heated by the solar heat of the solar cell panel 31 by the panel heat exchanger 32, and further heated by the heat recovery heat exchanger 4 of the fuel cell 7. It is heated by cooling water or the like that has absorbed the exhaust heat, and returns to the upper part of the hot water storage tank 1 as hot water. The exhaust heat generated along with the power generation in the fuel cell 7 is recovered into the cooling water in the cooling water path, and is transferred to the heat recovery heat exchanger 4 by the cooling water circulation pump 5 to heat the water from the hot water storage tank 1.

  In addition, in order to supply water to the hot water storage tank 1 or to supply hot water from the hot water storage tank 1 to the outside, the water supply inlet pipe 9, the pressure reducing valve 10, the first water supply pipe 11, the second water supply pipe 12, the hot water supply pipe 13, and the mixing valve 14 are used. The hot water supply outlet pipe 15 is provided. Water supply to the hot water storage tank 1 is performed via a pressure reducing valve 10 and a first water supply pipe 11 from a water supply inlet pipe 9 connected to a general water supply pipe. Hot water from the hot water storage tank 1 was discharged from the water supplied via the water supply inlet pipe 9, the pressure reducing valve 10, and the second water supply pipe 12 and from the upper part of the hot water storage tank 1 via the hot water discharge pipe 13. Hot water is mixed at an appropriate temperature by the mixing valve 14 and supplied to the outside through the hot water supply outlet pipe 15.

  Here, in the hybrid power generation system of the present embodiment, a bypass path that bypasses the panel heat exchanger 32 and a bypass path 41 that bypasses the heat recovery heat exchanger 4 are provided in the middle of the heat recovery path. . Further, panel switching means 34 and bypass switching means 36 for switching water flow to panel heat exchanger 32 and bypass path, heat exchanger switching means 42 for switching water flow to heat recovery heat exchanger 4 and bypass path 41, and Bypass switching means 43 is provided. Each of the panel switching means 34, the bypass switching means 36, the heat exchanger switching means 42 and the bypass switching means 43 is constituted by, for example, an electromagnetic valve, and normally the panel switching means 34 and the heat exchanger switching means 42 are opened. The bypass switching means 36 and 43 are closed. Further, on the outlet side of the panel heat exchanger 32, heat exchange outlet temperature detecting means 44 for detecting the temperature of the hot water storage is provided. Further, on the inlet side of the heat recovery heat exchanger 4, a feed water temperature detecting means 38 for detecting the temperature of the inflowing water is provided, and hot water after heat recovery from the panel heat exchanger 32 and water from the hot water storage tank 1 are provided. And a mixing valve 37 for adjusting the temperature to a predetermined temperature.

  In general, when the surface temperature of a solar cell increases, the power generation efficiency decreases. In particular, as in the summer, when the amount of solar radiation is large and the outside air temperature is high, the power generation efficiency tends to decrease. During the daytime in the summer, the power load due to the use of cooling is large, so the most amount of power is required throughout the year. In such a period, a decrease in the power generation efficiency of the system is not preferable in order to ensure energy saving. According to the present embodiment, by using the water in the hot water storage tank 1 to cool the solar cell panel 31 via the panel heat exchanger 32, the increase in the surface temperature of the solar cell panel 31 is suppressed, and sunlight This can improve the power generation efficiency.

  On the other hand, according to the present embodiment, the panel heat exchanger 32 can recover the heat of the solar cell panel 31 and heat the water in the hot water storage tank 1. That is, as a heat source for hot water storage in the hot water storage tank 1, not only exhaust heat of the fuel cell 7 but also solar heat can be utilized through the panel heat exchanger 32. According to this, it becomes possible to ensure a sufficient amount of heat for the hot water supply load at home.

  Further, according to the present embodiment, the outlet water temperature of the panel heat exchanger 32 can be detected, and when the temperature is higher than a predetermined value, it can be switched to the path 41 that bypasses the heat recovery heat exchanger 4. When the outside air temperature is high and the amount of solar radiation is large as in the daytime in summer, the amount of heat recovered by the panel heat exchanger 32 is increased, and the outlet temperature of the panel heat exchanger 32 can be kept high. On the other hand, when the temperature of the hot water storage becomes high, the temperature necessary for cooling the fuel cell 7 cannot be secured. As described above, when it is determined that the fuel cell 7 cannot be sufficiently cooled, the heat recovery path is switched to a path that bypasses the heat recovery heat exchanger 4. Thereby, the pump power required for the circulation of hot water storage can be suppressed, and the power consumption of the system can be reduced.

  Furthermore, according to the present embodiment, the temperature of the water flowing into the heat recovery heat exchanger 4 by mixing the water from the hot water storage tank 1 with the hot water heated by the panel heat exchanger 32 using the mixing valve 37. Can be adjusted to a constant temperature. According to this, even when the outlet water temperature of the panel heat exchanger 32 is high, the temperature of the hot water storage required for cooling the fuel cell 7 can be secured, and the operation of solar power generation and fuel cell power generation is facilitated. Since both can be achieved, the energy saving and reliability of the system can be improved.

  As described above, according to the present embodiment, it is possible to provide a hybrid power generation system that has a simple configuration, high power generation efficiency, and excellent energy saving and reliability.

In this embodiment, as means for switching the path for bypassing each heat exchanger, for example, a solenoid valve type panel switching means 34, a bypass switching means 36, and a heat exchanger switching means 42 are used.
However, when the mixing valve 37 has not only the function of mixing the fluids of a plurality of flow paths but also the function of switching the flow paths, these may be omitted, and only the mixing valve 37 may be substituted. .

  According to the present invention, the efficiency is improved with a simple configuration, and the present invention is useful in a technical field such as a hybrid power generation system in which high energy saving is required.

DESCRIPTION OF SYMBOLS 1 Hot water storage tank 2 Hot water circulation pump 3 Heat recovery piping 4 Heat recovery heat exchanger 5 Cooling water circulation pump 6 Cooling water piping 7 Fuel cell 9 Water supply inlet pipe 10 Pressure reducing valve 11 First water supply pipe 12 Second water supply pipe 13 Hot water supply pipe 14 , 37 Mixing valve 15 Hot water supply outlet pipe 21 Fuel cell unit 22 Hot water storage unit 25 Wattmeter 31 Solar cell panel 32 Panel heat exchanger 34 Panel switching means 35 Bypass piping 36, 43 Bypass switching means 42 Heat exchanger switching means

Claims (7)

A fuel cell, solar panel, and hot water storage tank
A heat recovery path in which the hot water storage tank, a panel heat exchanger for cooling the solar cell panel, and a heat recovery heat exchanger for recovering exhaust heat of the fuel cell are successively connected in an annular manner by a heat recovery pipe; A bypass path that bypasses the panel heat exchanger in a heat recovery path;
A hybrid power generation system provided with switching means for switching water flow to the bypass path. The hybrid power generation system according to claim 1, wherein the amount of generated power of the solar cell panel is detected, and when the detected amount of generated power is smaller than a predetermined value, the switching means is switched to a bypass path that bypasses the panel heat exchanger. The hybrid power generation system according to claim 1, wherein the surface temperature of the solar cell panel is detected, and the switching means is switched to a bypass path that bypasses the panel heat exchanger when the detected surface temperature is lower than a predetermined value. The hybrid power generation according to claim 1, wherein the water temperature at the inlet and outlet of the panel heat exchanger is detected, and the switching means is switched to a bypass path that bypasses the panel heat exchanger when the detected temperature difference is smaller than a predetermined value. system. A mixing valve that adjusts the hot water after heat recovery from the panel heat exchanger and the water from the hot water storage tank to a predetermined temperature is further provided, and the temperature of the water flowing into the heat recovery heat exchanger is controlled to a predetermined temperature or less. Item 2. The hybrid power generation system according to Item 1. A fuel cell, solar panel, and hot water storage tank
A heat recovery path in which the hot water storage tank, a panel heat exchanger for cooling the solar cell panel, and a heat recovery heat exchanger for recovering exhaust heat of the fuel cell are successively connected in an annular manner by a heat recovery pipe; A bypass path that bypasses the heat recovery heat exchanger in the heat recovery path;
A hybrid power generation system provided with switching means for switching water flow to the bypass path. The hybrid power generation system according to claim 6, wherein the water temperature at the outlet of the panel heat exchanger is detected, and when the detected temperature is higher than a predetermined value, switching to a bypass path that bypasses the heat recovery heat exchanger is performed.

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