Thermal storage system
The heat storage system addresses the inefficiency of using expensive daytime power by storing surplus electricity as heat using solid particles, ensuring balanced electricity supply and demand, and maintaining efficient heat generation.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- CENTRAL RESEARCH INSTITUTE OF ELECTRIC POWER INDUSTRY
- Filing Date
- 2022-06-10
- Publication Date
- 2026-07-29
AI Technical Summary
Existing systems for supplying high-temperature heat, such as superheated steam, often require immediate generation using expensive daytime power, failing to effectively utilize inexpensive surplus electricity and contributing to uneven power supply and demand.
A heat storage system comprising a heat exchange unit, high-temperature and low-temperature storage units, a transport unit, and heating units that utilize surplus electricity and alternative energy sources to store and release heat as needed, using solid heat storage particles.
The system effectively utilizes surplus electricity for heat storage, reducing reliance on expensive daytime power and contributing to a balanced electricity supply and demand, while maintaining efficient heat generation and minimizing device corrosion.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to a heat storage system.
Background Art
[0002] It is known that factories manufacturing various products etc. have a demand for a considerable amount of heat. Most of it is for relatively low-temperature heat demand below 200°C, but there is also a demand for relatively high-temperature heat above 200°C. The latter heat demand is expected to increase in the future.
[0003] For relatively high-temperature heat demand, supplying superheated steam has been carried out. For example, an electric superheater that superheats water by an induction heating method to generate superheated steam is known (see Patent Document 1).
[0004] Assuming an increase in future heat demand, it is desirable to generate superheated steam using inexpensive surplus power at night etc. However, since an electric superheater needs to immediately generate superheated steam according to the heat demand, it may sometimes have to use expensive daytime power. For this reason, there is also a problem that surplus power cannot be effectively utilized and it cannot contribute to the leveling of power supply and demand.
[0005] Note that such a problem exists not only when supplying superheated steam but also when supplying high-temperature gas.
Prior Art Documents
Patent Documents
[0006]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0007] In view of the above circumstances, the present invention aims to provide a heat storage system that can store and effectively utilize inexpensive surplus electricity as heat, thereby contributing to the leveling of electricity supply and demand. [Means for solving the problem]
[0008] One aspect of the present invention for achieving the above objective is a heat storage system characterized by comprising: a heat exchange unit that exchanges heat between a fluid and solid heat storage particles to convert the fluid into a high-temperature gas; a high-temperature storage unit for storing the solid heat storage particles; a low-temperature storage unit for storing the solid heat storage particles; a transport unit for transporting the solid heat storage particles from the low-temperature storage unit to the high-temperature storage unit, from the high-temperature storage unit to the heat exchange unit, and from the heat exchange unit to the low-temperature storage unit; a first heating unit that heats the solid heat storage particles transported from the low-temperature storage unit to the high-temperature storage unit to a first temperature using heat obtained from electricity; and a second heating unit that heats the solid heat storage particles transported from the heat exchange unit to the low-temperature storage unit to a second temperature lower than the first temperature using heat obtained from energy other than electricity. [Effects of the Invention]
[0009] According to the present invention, a heat storage system is provided that can store and effectively utilize inexpensive surplus electricity as heat, thereby contributing to the leveling of electricity supply and demand. [Brief explanation of the drawing]
[0010] [Figure 1] This is a diagram showing the configuration of the heat storage system. [Figure 2] This is a diagram showing the configuration of the heat exchange section. [Figure 3] This is a diagram showing the configuration of the heat exchange section. [Modes for carrying out the invention]
[0011] An embodiment of the heat storage system of the present invention will be described. Figure 1 illustrates the configuration of the heat storage system 1. The heat storage system 1 consists of a group of devices that generate and supply superheated steam, an example of a high-temperature gas, to the facilities of consumers (such as factories) that require heat, by effectively utilizing surplus electricity. Specifically, the heat storage system 1 includes a heat exchange unit 2, a high-temperature storage unit 3, a low-temperature storage unit 4, a transport unit 5, an electric heater 6, a solar heater 7, a supply line 8, a preheating line 9, a recovery line 10, and a preheater 11.
[0012] The heat exchange unit 2 is a device that exchanges heat between water vapor and solid heat storage particles to convert the water vapor into superheated steam. The heat exchange by the heat exchange unit 2 may be carried out by directly exchanging heat between water vapor and solid heat storage particles, or by indirectly exchanging heat. The specific configuration of the heat exchange unit 2 will be described later.
[0013] A preheating line 9 is connected to the heat exchange section 2. A preheater 11 is provided along the preheating line 9. A recovery line 10 branches off from the supply line 8 and is connected to the preheater 11. Water flows through the preheating line 9, mixes with superheated steam in the preheater 11 to become steam, and is supplied to the heat exchange section 2. The water that forms the steam may be condensed superheated steam that has finished its work supplied to the customer's equipment, or it may be water prepared separately.
[0014] Solid heat storage particles are particles that can maintain sensible heat for a long period of time. Specific examples of solid heat storage particles include sand and crushed stone, which can maintain heat from approximately 150°C to 600°C for about a day. While there are no particular limitations on the particle size or shape of solid heat storage particles, it is preferable that they be a few millimeters or less.
[0015] The high-temperature storage unit 3 is a device for storing solid heat storage particles. The stored solid heat storage particles are transported to the heat exchange unit 2. The high-temperature storage unit 3 is equipped with a container having an insulating structure, and the solid heat storage particles are stored in this container. The solid heat storage particles stored in the high-temperature storage unit 3 are heated by an electric heater 6 and are relatively hotter than the solid heat storage particles stored in the low-temperature storage unit 4.
[0016] The low-temperature storage unit 4 is a device for storing solid heat storage particles. The stored solid heat storage particles are transported to the high-temperature storage unit 3. The low-temperature storage unit 4 is equipped with a container having an insulating structure, and the solid heat storage particles are stored in this container. The solid heat storage particles stored in the low-temperature storage unit 4 are heated by a solar heater 7 and are relatively lower in temperature than the solid heat storage particles stored in the high-temperature storage unit 3.
[0017] The transport unit 5 consists of a group of devices that transport solid heat storage particles from the low-temperature storage unit 4 to the high-temperature storage unit 3, and from the high-temperature storage unit 3 to the heat exchange unit 2. Specifically, it consists of conveyors for transporting solid heat storage particles, and since these are well-known, details are omitted. The transport unit 5 transports solid heat storage particles from the high-temperature storage unit 3 to the heat exchange unit 2 according to the required amount of solid heat storage particles in the heat exchange unit 2. The transport unit 5 also transports solid heat storage particles from the low-temperature storage unit 4 to the high-temperature storage unit 3 so that a predetermined amount of solid heat storage particles is maintained in the high-temperature storage unit 3. Furthermore, the transport unit 5 transports solid heat storage particles discharged from the heat exchange unit 2 to the low-temperature storage unit 4.
[0018] The electric heater 6 is a device that heats the solid heat storage particles supplied from the low-temperature storage unit 4 to the high-temperature storage unit 3 using heat obtained from surplus commercial power. The temperature reached by heating with the electric heater 6 is defined as the first temperature. The electric heater 6 may store and heat a certain amount of solid heat storage particles transported by the transport unit 5, or it may heat the solid heat storage particles being transported by the transport unit 5. The configuration of such an electric heater 6 is publicly known, so details are omitted.
[0019] The solar heater 7 is a device that heats the solid heat storage particles supplied from the heat exchange unit 2 to the low-temperature storage unit 4 using heat obtained from energy other than electricity, here solar heat. Let the temperature reached after heating by the solar heater 7 be the second temperature. This second temperature is lower than the first temperature.
[0020] Solar heat can be obtained by using a solar furnace that condenses sunlight using a lens, a reflector, etc. to create a high temperature. Due to the heat obtained by such a solar furnace, the solar heater 7 heats the solid heat storage particles supplied to the solar heater 7. For example, by directly irradiating the solid heat storage particles transported by the transport unit 5 with sunlight or irradiating the solid heat storage particles with sunlight condensed by a lens or a reflector, solar heat can be stored in the solid heat storage particles. Alternatively, a heat medium such as a fluid can be heated with the heat obtained in the solar furnace, and the solid heat storage particles can be heated directly or indirectly by the heat medium.
[0021] The operation of the heat storage system 1 with the above-described configuration will be described. The solid heat storage particles that have completed their work in the heat exchange unit 2 are discharged from the heat exchange unit 2 and transported to the low-temperature storage unit 4 by the transport unit 5. Let the transport amount of the solid heat storage particles be 1 kg / s. Let the temperature of the solid heat storage particles that have completed their work be 150°C. On the way of being transported to the low-temperature storage unit 4 by the transport unit 5, the solid heat storage particles are heated by the solar heater 7. The solid heat storage particles are heated to 200°C as an example of the second temperature and stored in the low-temperature storage unit 4.
[0022] Next, the solid heat storage particles are transported from the low-temperature storage unit 4 to the high-temperature storage unit 3 by the transport unit 5. The timing of this transport may be arbitrary, but it is preferably performed during a time period when there is surplus power such as at night. The solid heat storage particles are heated to 600°C as an example of the first temperature by the electric heater 6 and stored in the high-temperature storage unit 3.
[0023] Then, solid heat storage particles are continuously or intermittently supplied from the high-temperature storage unit 3 to the heat exchange unit 2. In the heat exchange unit 2, superheated steam is generated according to the demand of the customer's equipment. When the flow rate of the steam supplied to the heat exchange unit 2 is 1 kg / s and the temperature is 100°C, by exchanging heat with solid heat storage particles at 600°C, superheated steam with a flow rate of 1 kg / s and a temperature of 550°C can be supplied to the customer's equipment. In this case, the heat exchange amount of the heat exchange unit 2 is 450 kW.
[0024] The high-temperature storage unit 3 is preferably designed to store, for example, the amount of solid heat storage particles required in a day. This can significantly reduce the possibility that the required amount of solid heat storage particles in the heat exchange unit 2 runs out. Of course, when the solid heat storage particles in the high-temperature storage unit 3 are likely to run out, the solid heat storage particles in the low-temperature storage unit 4 can be heated by the electric heater 6 and supplied to the high-temperature storage unit 3. In that case, relatively expensive daytime power rather than surplus nighttime power will be used, but the amount of that power can be suppressed.
[0025] Here, the specific configuration of the heat exchange unit 2 will be described with reference to Fig. 2(a). The heat exchange unit 2 includes a heat exchange chamber 20. The heat exchange chamber 20 is configured such that solid heat storage particles are introduced from the upper part and discharged from the lower part. Specifically, an inlet 21 for high-temperature solid heat storage particles (hereinafter abbreviated as high-temperature particles) is provided at the upper part of the heat exchange chamber 20. Also, a discharge part 24 for solid heat storage particles that have become low temperature after heat exchange (hereinafter abbreviated as low-temperature particles) is provided at the lower part of the heat exchange chamber 20. The inlet 21 is connected to the high-temperature storage unit 3 via the transport unit 5. The discharge part 24 is connected to the low-temperature storage unit 4 via the transport unit 5.
[0026] Furthermore, the heat exchange chamber 20 is configured such that steam is introduced from the lower part and discharged as superheated steam from the upper part. Specifically, an exhaust part 22 for superheated steam is provided at the upper part of the heat exchange chamber 20. Also, a funnel-shaped plate 23 that slopes downward toward the discharge part 24 is provided at the lower part of the heat exchange chamber 20. The plate 23 is in a mesh shape or has pores formed.
[0027] Plate 23 is supplied with steam from below via a preheating line 9. High-temperature particles that have fallen from the input section 21 temporarily accumulate on the upper surface of plate 23. The steam passes through plate 23, and as it passes through the gaps between the high-temperature particles, it undergoes heat exchange and becomes superheated steam. The superheated steam that has passed through the high-temperature particles is discharged from the exhaust section 22 and supplied to the customer's equipment.
[0028] Furthermore, a dispersion member 25 for dispersing high-temperature particles is provided at the top of the heat exchange chamber 20. High-temperature particles falling from the input section 21 are dispersed in a planar direction by the dispersion member 25. As a result, the high-temperature particles spread uniformly inside the heat exchange chamber 20 as they fall, allowing for more reliable contact between the water vapor and the high-temperature particles for heat exchange.
[0029] As described above, the heat exchange unit 2 is configured to drop high-temperature particles from the top and supply steam from the bottom. The solid heat storage particles accumulated at the bottom of the heat exchange chamber 20 become hotter as they move towards the top, and the solid heat storage particles falling are also hotter closer to the input unit 21. Therefore, as the steam moves from the plate 23 to the exhaust unit 22, it comes into contact with solid heat storage particles ranging from low temperature to high temperature. In other words, it does not come into contact with low-temperature solid heat storage particles near the exhaust unit 22, which is close to the customer's equipment. This allows for efficient heat exchange.
[0030] Furthermore, since the plate 23 is formed in a funnel shape, it is easier to discharge the solid heat storage particles to the discharge section 24. In other words, the flowability (fluidity) of the solid heat storage particles in the heat exchange section 2 is improved. This improvement in fluidity leads to the rapid discharge of the solid heat storage particles as their temperature drops, thus making it possible to more reliably maintain the target temperature of the superheated steam exhausted from the heat exchange section 2.
[0031] As shown in Figure 2(b), the plate 23 is not limited to a funnel shape, but may also be flat. Even with such a shape, solid heat storage particles will temporarily accumulate on the plate 23, but the solid heat storage particles can be discharged from the discharge section 24, ensuring fluidity.
[0032] Figure 3(a) illustrates other specific configurations of the heat exchange unit 2. The heat exchange unit 2 includes a heat exchange chamber 30. The heat exchange chamber 30 is configured so that solid heat storage particles are introduced from the top and discharged from the bottom. Specifically, a high-temperature particle introduction section 31 is provided at the top of the heat exchange chamber 30. A low-temperature particle discharge section 34 is provided at the bottom of the heat exchange chamber 30. The introduction section 31 is connected to the high-temperature storage unit 3 via a transport section 5. The discharge section 34 is connected to the low-temperature storage unit 4 via a transport section 5.
[0033] In a cross-sectional view parallel to the vertical direction, the heat exchange chamber 30 has a dispersion section 35 formed in which the wall surface protrudes toward the center and slopes downward. High-temperature particles are introduced into the heat exchange chamber 30 from the input section 31 and fall as they are guided horizontally by the dispersion section 35. Due to this dispersion section 35, the high-temperature particles spread uniformly inside the heat exchange chamber 30 as they fall, so that water vapor can come into contact with the high-temperature particles more reliably and heat exchange can be performed.
[0034] Furthermore, the heat exchange chamber 30 is configured such that steam is introduced from the bottom, becomes superheated steam, and is discharged from the top. Specifically, a superheated steam exhaust section 32 is provided at the top of the heat exchange chamber 30. In addition, a mesh-like plate 33 is provided at the bottom of the heat exchange chamber 30, adjacent to the discharge section 34. Steam is supplied to the plate 33 from below via the preheating line 9.
[0035] The steam passes through plate 33 and exchanges heat with high-temperature particles falling through heat exchange chamber 30 to become superheated steam. The superheated steam is discharged from exhaust section 32 and supplied to the customer's equipment.
[0036] As described above, the heat exchange unit 2 is configured to drop high-temperature particles from the top and supply steam from the bottom. The solid heat storage particles falling through the heat exchange chamber 30 are hotter as they move towards the top. Therefore, as the steam moves from the plate 33 towards the exhaust unit 32, it comes into contact with solid heat storage particles ranging from low temperature to high temperature. In other words, it does not come into contact with low-temperature solid heat storage particles near the exhaust unit 32, which is close to the customer's equipment. This allows for efficient heat exchange.
[0037] Furthermore, as shown in Figure 3(b), the plate 33 may be inclined downward toward the discharge section 34. By inclining the plate 33 in this way, it is easier to discharge the solid heat storage particles toward the discharge section 34, and the fluidity of the solid heat storage particles in the heat exchange section 2 is improved. This improvement in fluidity leads to the rapid discharge of the solid heat storage particles whose temperature has dropped, so the target temperature of the superheated steam exhausted from the heat exchange section 2 can be maintained more reliably.
[0038] As described above, the heat storage system 1 of the present invention stores heat obtained from surplus electricity in solid heat storage particles, and generates superheated steam using these solid heat storage particles to supply to the customer's equipment. In other words, it stores surplus electricity from the commercial power supply during times such as nighttime as heat. Therefore, even in cases where superheated steam needs to be generated immediately in response to heat demand, it is sufficient to use solid heat storage particles that have been stored in advance, eliminating the need to use expensive daytime electricity. In this way, the heat storage system 1 can effectively utilize surplus electricity. Furthermore, even during the daytime or in winter when electricity demand is tight, it can use non-surplus electricity from the commercial power supply without using it, or reduce its usage, thus contributing to the leveling of electricity supply and demand.
[0039] Furthermore, the heat storage system 1 uses solid heat storage particles as a medium for heat storage. This makes it possible to avoid corrosion of each device, such as the heat exchange unit 2, compared to when molten salt is used as the medium. Molten salt becomes solid if its melting point cannot be maintained. Therefore, after heat exchange is complete, the molten salt solidifies and becomes difficult to recover. On the other hand, in the present invention, since the heat medium is solid particles, it is easy to recover, and as shown in Figure 1, it can be easily recovered from the heat exchange unit 2 and reheated.
[0040] Furthermore, the heat storage system 1 heats the solid heat storage particles using heat obtained not only from electricity but also from energy sources such as solar heat, and then proceeds to heat them using electricity. By performing heating in stages in this way, the amount of electricity used by the electric heater 6 can be reduced, thereby lowering running costs.
[0041] Furthermore, using solar heat as the energy source yields even greater benefits. Solar heat is used as a heating source to bring the solid heat storage particles to a relatively low temperature. Because it does not require high temperatures, the solar heater 7 of the present invention can be used as a heat source even in solar furnaces installed on small plots of land or in locations with low solar radiation. Moreover, the heat storage system 1 of the present invention does not use solar heat directly to generate superheated steam, but rather to store heat in solid heat storage particles. Therefore, it has the effect of being less affected by fluctuations in solar radiation.
[0042] Generally, it is known that the higher the temperature at which solar heat is recovered, the greater the amount of radiation. Specifically, the amount of radiation is proportional to the fourth power of the absolute temperature. Therefore, if the second temperature of 600°C for solid heat storage particles is to be supplied solely by solar heat, not only will the scale of the solar furnace have to be increased, but the radiation loss will also be large.
[0043] On the other hand, the heat storage system 1 of the present invention uses solar heat as a heat source to raise the solid heat storage particles to a low first temperature (for example, 200°C), thus suppressing radiative loss.
[0044] As shown in Figures 2 and 3, the heat exchange section 2 flows from top to bottom, even if the solid heat storage particles temporarily remain there. This method of heat exchange, in which solid heat storage particles are fluidized, is called fluidized bed heat exchange. On the other hand, a method of heat exchange in which solid heat storage particles are introduced into the heat exchange chamber 20 or heat exchange chamber 30 and stored there, while water vapor is brought into contact with the solid heat storage particles, is called fixed bed heat exchange.
[0045] Fixed-bed heat exchangers require alternating heat extraction from fixed heat storage particles into gases such as water vapor and heat storage into solid heat storage particles. It is known that the temperature of the fixed heat storage particles decreases with each repetition of this heat extraction and storage process. Therefore, fixed-bed heat exchangers cannot fully utilize the heat stored in the fixed heat storage particles. However, fluidized-bed heat exchangers do not have this exchange process and do not suffer from the problem of temperature decrease in the fixed heat storage particles, thus allowing for more efficient heat extraction from solid heat storage particles compared to fixed-bed heat exchangers. Furthermore, fixed-bed heat exchangers cannot perform heat extraction and heat storage simultaneously. On the other hand, fluidized-bed heat exchangers can perform heat extraction in the heat exchange section 2 and heat storage in the electric heater 6 or solar heater 7 simultaneously. Therefore, superheated steam can be supplied continuously without interruption for heat storage.
[0046] Furthermore, by employing a fluidized bed heat exchange system, heat can be directly recovered by solar energy while the fixed heat storage particles are being transported by the transport unit 5.
[0047] As shown in Figure 1, the heat storage system 1 is equipped with a preheater 11 that uses a portion of the superheated steam supplied to the supply line 8 as a heat source to convert water into steam. Compared to the case where water is converted into superheated steam using solid heat storage particles, the fluid solid heat storage particles can more reliably convert steam into superheated steam. In addition, in this invention, water may be supplied to the heat exchange section 2 and superheated steam may be produced by heat exchange between the solid heat storage particles and the water.
[0048] The present invention is not limited to the embodiments described above. For example, the heat exchange unit 2 generates and supplies superheated steam, but is not limited to this. For example, air may be taken into the heat exchange unit 2 and heat-exchanged to produce high-temperature air (an example of the high-temperature gas described in the claims). The present invention can also be applied to cases where various other gases, such as inert gases, are heated to high temperatures.
[0049] Figures 2 and 3 illustrate a configuration in which solid heat storage particles are supplied from the top of the heat exchange chamber and discharged from the bottom of the heat exchange chamber, but the configuration is not limited to this. In other words, the solid heat storage particles only need to be supplied in a manner that they fall from above, and the upper part (input section) of the claim only needs to be relatively higher than the lower part (discharge section).
[0050] Furthermore, while an example configuration was given in which steam is supplied from the bottom of the heat exchange chamber and superheated steam is discharged from the top of the heat exchange chamber, the configuration is not limited to this. In other words, the steam and superheated steam can be supplied from bottom to top, and the upper part (exhaust section) of the claim only needs to be relatively higher than the lower part (plate).
[0051] In the heat exchange chamber, water vapor is supplied so that it passes through temporarily accumulated solid heat storage particles, but the heat exchange is not limited to this method. For example, the heat exchange chamber may be configured so that no or very few solid heat storage particles accumulate, and heat exchange may be performed by flowing water vapor over the solid heat storage particles falling from above to below. Furthermore, water may be flowed over the solid heat storage particles temporarily accumulated in the heat exchange chamber to evaporate them and produce superheated steam.
[0052] While the solar thermal heater 7 is exemplified as one that uses solar heat as a heat source, it is not limited to this. Heat obtained using energy other than electricity, such as renewable energy, may also be stored in fixed heat storage particles.
[0053] The preheater 11 is exemplified as one that directly mixes water and superheated steam to produce steam, but it is not limited to this. For example, water may be heated indirectly with superheated steam. Furthermore, the heat source for the preheater 11 is not limited to superheated steam; solid heat storage particles may be used, or other heat sources may be used.
[0054] The transport unit 5 is not limited to a configuration that requires power, such as a conveyor. For example, the heat exchange unit 2, high-temperature storage unit 3, and low-temperature storage unit 4 may be arranged in this order from lowest to highest height, and the solid heat storage particles may be transported to the lower devices by their own weight.
[0055] The thermal storage system 1 may be deployed separately from the customer's facilities or within the customer's facilities. Furthermore, the temperature, flow rate, and heat exchange amount of the solid thermal storage particles and superheated steam shown in Figure 1 are examples and can be appropriately set according to the scale of the thermal storage system. [Explanation of Symbols]
[0056] 1…Heat storage system, 2…Heat exchange unit, 3…High-temperature storage unit, 4…Low-temperature storage unit, 5…Transport unit, 6…Electric heater (first heating unit), 7…Solar heater (second heating unit), 11…Preheater (third heating unit)
Claims
1. A heat exchange section that exchanges heat between a fluid and solid heat storage particles to turn the fluid into a high-temperature gas, A high-temperature storage section for storing the solid heat storage particles, A low-temperature storage section for storing the solid heat storage particles, A transport unit that transports the solid heat storage particles from the low-temperature storage unit to the high-temperature storage unit, from the high-temperature storage unit to the heat exchange unit, and from the heat exchange unit to the low-temperature storage unit, A first heating unit heats the solid heat storage particles, which are transported from the low-temperature storage unit to the high-temperature storage unit, to a first temperature using heat obtained from electricity. The system includes a second heating unit that heats the solid heat storage particles, which are transported from the heat exchange unit to the low-temperature storage unit, to a second temperature lower than the first temperature using heat obtained from energy other than electricity, The second heating section is provided on the way from the heat exchange section to the low-temperature storage section, The high-temperature storage unit stores the solid heat storage particles heated by the first heating unit. The low-temperature storage unit stores the solid heat storage particles heated by the second heating unit. The first heating unit heats the solid heat storage particles with surplus power, The second heating unit heats the solid heat storage particles with solar heat. A heat storage system characterized by the following features.
2. A heat storage system according to claim 1, The fluid that undergoes heat exchange in the heat exchange section is a gas. The heat exchange section includes a heat exchange chamber, The heat exchange chamber is The aforementioned solid heat storage particles are introduced from the top and discharged from the bottom. The aforementioned gas is introduced from the bottom, becomes a high-temperature gas, and is discharged from the top. It is configured in such a way A heat storage system characterized by the following features.
3. A heat storage system according to claim 1, The third heating unit uses a portion of the high-temperature gas discharged from the heat exchange unit as a heat source and converts the liquid fluid supplied to the heat exchange unit into a gas. A heat storage system characterized by the following features.