JP2001090509A - Cryogenic power generating system using liquid air - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance power storage efficiency by effectively utilize a special character of liquid air without disusing exergy of a very low temperature of cold contained in the liquid air to improve electric power (power) reconversion or a thermodynamic cycle for recovery, when the reconversion to the electric power (power) or the recovery is carried out. SOLUTION: After pressure of the liquid air is raised using a pump 3 to be vaporized in a heat exchanger 4, a temperature of a working fluid (air) is lowered by the second expansion equipment 7 and an expansion valve 12 to generate new cold heat. The atmospheric air introduced into the thermodynamic cycle by another system is cooled in the heat exchanger 4 using the generated cold heat and the cold heat generated when the liquid air is vaporized as a low temperature heat source for the cycle, followed to be compressed at the very low temperature by the first compressor 9 so as to be brought into the working fluid, and is joined with the working fluid of the vaporized air to be supplied to an internal combustion engine 10 so as to drive a generator 11 by the engine 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combined thermodynamic cycle for storing electric energy as ultra-low-temperature exergy of liquid air and reconverting and recovering the cold energy of the liquid air into electric power (power) according to demand. It relates to a cold power generation system.

[0002]

2. Description of the Related Art Conventionally, as a practically used electric power storage system, a system using pumped storage power generation using a surplus electric power at night or a storage battery has been known.

However, in the case of an electric power storage system using pumped storage power generation, a location is located under limited conditions such as a mountainous area far from a demand area. On the other hand, in the case of a power storage system using a storage battery, it can be installed close to a demand area, but if it is used for a long time, an excessive capital investment is required.

In order to solve such a problem, various systems for storing electric power using liquid air as a medium have recently been proposed. In the case of this system, when power is stored, it is necessary to cool the air to an extremely low temperature in order to produce liquid air, and this refrigeration requires a large amount of energy. Generally, there is a coefficient of performance (or operation coefficient) as a theoretical value for evaluating the performance of a refrigerator.

Generally, the theoretical coefficient of performance εr is given by εr = T ₁ / (T ₂ −T ₁ ), where T ₁ is the low temperature of the refrigeration cycle and T ₂ is the high temperature of the refrigeration cycle. (Expression 1)

[0006] The temperature of liquid air is about 80K under atmospheric pressure.
(-193 ° C). Set the high temperature side of the cycle to 30
Substituting 0K (27 ° C.) into Equation 1 above gives a theoretical coefficient of performance εr of about 0.36.

[0007] In the sense that it is compared with the usual familiar technology, the theoretical coefficient of performance εr when the -15 ° C freezer is operated in the environment of 27 ° C is approximately 6.1 when calculated similarly using the equation (1). It is.

[0008] Regarding the coefficient of performance εr, regardless of the type of refrigerant, the smaller the value, the greater the energy required for refrigeration. Therefore, liquid air production requires about 17 times as much energy as ordinary refrigeration.

[0009] In addition, in a practical device, various factors of efficiency decrease overlap, so that the coefficient of performance is further reduced, and the production of liquid air involves the consumption of power (power) corresponding thereto. In a liquid air producing apparatus currently in operation for commercial use, liquid air is converted to a standard state by about 0.5 to 0.5.
The rate of power (power) consumption is about 8 kwh / m ³ _N. In addition, m ³ _N is a standard cubic meter, and means m ³ in a standard state of physics (0 ° C., 760 mmHg).

[0010] Therefore, the electric power (power) is stored as the ultra-low temperature exergy of the cold air of the liquid air. Therefore, when the electric power (power) is converted and recovered from the liquid air, the ultra-low temperature exergy is used. Loss (EL) must be minimized.

According to the “Superconductivity and Low Temperature Engineering Handbook I.4.1.1.1 [3]” (Ohm Co., 1993), the exergy loss EL is based on the ambient temperature (room temperature) T ₀ . From the temperature T1 to T2 in the thermodynamic cycle
Is flowing, the following equation is given.

EL = T ₀ ΔS = T ₀ q (T ₁ −T ₂ ) / (T ₁ · T ₂ ) (Equation 2) From the above Equation 2, the temperature difference (T _The larger ₁₋ T ₂ ), the greater the exergy loss.

[0013] In the conventionally proposed cryogenic power generation system using liquid air, the liquid air is directly heated by seawater, various kinds of waste heat, or the residual heat of a boiler to convert the air into electric power (power).
Although there are many types of recovery systems, in these systems, since the temperature difference between the liquid air and the heating source is large, the exergy loss becomes large as shown in Expression 2, and finally the electric power (power ) Has a remarkably low storage efficiency, making the technology economically impractical.

There has also been proposed a system in which the cold energy is transferred to a cold storage mechanism when liquid air is vaporized, and the air is cooled by the cold storage mechanism at the stage of producing the next liquid air.
In the case of this method, exergy that is discarded outside the thermodynamic cycle system is suppressed, but if the regenerator material is a sensible heat system, the temperature of the regenerator material changes with time as heat moves. In the case of storing a large amount of cold heat, it is necessary to take a large temperature difference from the working fluid or to install a huge amount of cold storage material. Also, in the case of the latent heat method, the temperature change of the cold storage material is a narrow temperature range, but since the range is fixed, in the case of a single type of cold storage material, the temperature difference between the ultra-low temperature of liquid air or the normal temperature of the atmosphere and the cold storage material is growing. Therefore, in the cold storage mechanism using a single cold storage material, exergy loss due to a large temperature difference in the process of heat transfer between the working fluid and the cold storage mechanism within the thermodynamic cycle cannot be suppressed.

The "energy storage type gas turbine power generation system" disclosed in JP-A-9-250360 and JP-A-10-238367 is divided into multiple stages using a refrigerant such as a liquid as a cold storage material. A method for storing cold is disclosed. These methods certainly reduce the exergy loss compared to the simple cold storage method, but also ignore the exergy loss due to the accumulated temperature difference between the cold storage material and the working fluid at each stage. Can not.

Japanese Patent Application Laid-Open No. 10-238366 describes that if a temperature difference of 10 K can be achieved, the storage efficiency is 8
7% "(paragraph number 0088).
In this case, the system uses solid sensible heat for the cold storage material, and can store a large amount of cold heat for a long time,
On the other hand, in order to maintain the temperature difference of the working fluid within 10 K for one cycle of the operation of transferring the cold heat to the working fluid, an enormous amount of cold storage material is required. For this reason, the expression is based on hypothetical assumptions, suggesting that it is not practical. Therefore, in a multi-stage regenerative storage system, the system configuration must be complicated, the construction cost of the equipment becomes excessive, and the operation and maintenance are complicated, and in addition to the technical difficulties, It is a technology with little practical use.

[0017]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, the present invention provides a cryogenic power generation system using liquid air which can achieve the following problems (1) to (6). The purpose is to provide. (1) Reconversion of electric power (power) stored as liquid air
When recovering, do not dispose of cold heat outside the thermodynamic cycle system. (2) Minimize the ultra-low temperature exergy loss of the cold of the liquid air in the process of operating the working fluid within the thermodynamic cycle. (3) Utilize the characteristics of liquid air as a low-temperature heat source in the thermodynamic cycle to generate new cold heat and reduce the compression work of the cycle. (4) By adding an internal combustion engine to the contents of the above items (1) to (3), power (power) storage efficiency of 100% or more is realized. (5) The system configuration should be easy for operation and maintenance, and economical. (6) To be able to install small- to medium-scale power storage facilities in a multi-polarized manner in close proximity to a demand area, thereby contributing to the leveling of power loads.

[0018]

SUMMARY OF THE INVENTION The object of the present invention is to provide a cryogenic power generating system for driving an internal combustion engine to generate electric power by utilizing the exergy of liquid air. A heat exchanger for exchanging heat with liquid air pumped by a pump, wherein the liquid air is vaporized by the heat exchanger, and the vaporized air is introduced into the internal combustion engine as combustion air. This is attained by a thermal power generation system characterized in that:

According to the present invention, exergy loss can be minimized by exchanging liquid air produced using surplus electric power at night with air in the atmosphere.

Air for exchanging heat with the liquid air in the heat exchanger is introduced into the thermodynamic cycle from the atmosphere in a different system from the thermodynamic cycle system from the pump to the internal combustion engine; After passing through the heat exchanger, the first
And the compressed air is supplied to the internal combustion engine as combustion air. With such a configuration,
By compressing the atmosphere at low temperatures, less compression power is required, the thermal efficiency of the cycle is improved, and exergy is minimized because no cold is released.

The working fluid for heat exchange with the liquid air in the heat exchanger circulates in a closed cycle of a system different from a thermodynamic cycle system from the pump to the internal combustion engine. A second compressor that compresses the working fluid that has exited the heat exchanger and a first expander that expands the compressed working fluid and performs work for power generation. . With the configuration in which the working fluid circulates in the closed cycle, dehumidification and CO
Eliminates the need for ancillary equipment such as _two devices.

After the liquid air pumped from the pump is vaporized into compressed air by the heat exchanger, a second expander is provided for causing the compressed air to perform work for power generation. It is good also as a structure which introduce | transduces the exhaust gas from into the said heat exchanger again. This second expander converts the enthalpy of the pressurized air into work and takes it out. Here, new cold is generated and added to the cold of the liquid air, so that the compression work of the cycle can be reduced and the thermal efficiency can be improved.

The liquid air pumped from the pump is
In the heat exchange process in a temperature range of 73K or less, an expansion valve for extracting and expanding a part in the state of liquid air or gaseous air is provided, and air coming out of the expansion valve is re-introduced to the low temperature side of the heat exchanger. It is good also as composition. If such an expansion valve is provided, the liquid air or gas air partially extracted from the heat exchanger is adiabatically free-expanded to lower the temperature again to the ultra-low temperature range, thereby generating new cold heat, Even when the inlet pressure of the expander is low, the temperature balance of the heat exchanger can be stabilized.

A third compressor may be provided for pre-compressing air introduced to the high temperature side of the heat exchanger for heat exchange with the liquid air before introducing the air into the heat exchanger. good. By compressing the air introduced into the heat exchanger in advance, the heat exchanger can be downsized. When a dehumidification / de-CO ₂ device is provided, the size and size of the device are improved and its function is improved.

[0025] The heat exchanger may be arranged to exchange heat with the liquid air immediately after being discharged from the pump.
Since the working fluid that exchanges heat with the liquid air can be cooled to an extremely low temperature, the compression work of the first compressor or the second compressor can be reduced, and thus the thermal efficiency of the cycle can be improved.

It is preferable that a heating device for heating the air introduced into the internal combustion engine and / or the working fluid circulating in the closed cycle to 374 K or more is provided. By increasing the temperature of the working fluid introduced into the internal combustion engine, the generated power can be increased and the thermal efficiency of the cycle can be improved.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a preferred embodiment of a cryogenic power generation system using liquid air according to the present invention will be described.
This will be described with reference to the drawings.

A first embodiment of a cryogenic power generation system using liquid air according to the present invention will be described with reference to a system diagram shown in FIG. 1 and a TS diagram shown in FIG.

In this cold power generation system, the liquid air producing apparatus 1 is driven by utilizing surplus electric power at night to liquefy air taken in from the outside. The liquefied air is introduced into the liquid air storage tank 2 and stored as cold heat.

The exergy of the cold air of the liquid air stored in this way is converted back to electric power and recovered as follows.

First, the liquid air (about 80K) stored in the liquid air storage tank 2 is pumped by, for example, 0.1 MPa.
To about 15 MPa, and introduced into the low-temperature side of the low-temperature heat exchanger 4 through the system 101.

The high-temperature side of the low-temperature heat exchanger 4 is made of liquid air.
Through a separate system 121 from the liquid air introduced into the
And the atmosphere has been introduced. This atmosphere is previously dehumidified / dehumidified.
CO _TwoFreezing inside the power generation cycle
To prevent system clogging due to dry ice production
And moisture and CO_TwoIs preferably removed.

In the low-temperature heat exchanger 4, the liquid air and the gas air exchange heat. A part (for example, about 50%) of the working fluid (liquid air) from the system 101 is exchanged for 273K during the heat exchange. It can be extracted via system 110 and guided to expansion valve 12 in the following temperature range: The remaining working fluid from the system 101 can be further heated in the low-temperature heat exchanger 4 and vaporized before being guided to the second expander 7 through the system 102. By means of the second expander 7, the working fluid from the system 102 works externally at the generator 11 via the internal combustion engine 10, thereby reducing the pressure and enthalpy and reducing the temperature to about 185K. Can be lowered.

On the other hand, the working fluid that has reached the expansion valve 12 has its temperature lowered to about 120 K to the ultra-low temperature range by adiabatic free expansion, and is again introduced into the low-temperature side of the low-temperature heat exchanger 4.
Approximately 180K by heat exchange with air introduced from another system 121
The temperature can be raised to a certain degree, and the working fluid discharged from the second expander 7 can be joined in the low-temperature heat exchanger 4 and further heated to reach the low-temperature economizer 5 as a heating device.

The air from the separate system 121 exchanges heat with the liquid air that has flowed out of the pump 3 and the low-temperature working fluid (air) that has flowed out of the second expander 7 and the expansion valve 12. After being cooled to 100 K), it reaches the first compressor 9 via the system 122. The first compressor 9 is driven by a motor M.

The cooling air from the separate system 122 is pressurized by the first compressor 9 and heated by the low-temperature economizer 5 using low-grade waste heat Q3 such as hot water for cooling the internal combustion engine 10, and then heated. It joins with the working fluid of the system 111 and reaches the high-temperature economizer 6 as a heating device.
And high-temperature and high-pressure (for example, 0.15 to 15 MPa, 373 to 873).
K) can be supplied to the internal combustion engine 10 as a working fluid. By supplying such a high-temperature and high-pressure working fluid to the internal combustion engine 10, the thermal efficiency of the engine can be improved. Further, since the working fluid of the system 123 is about 240K, the high-temperature side of the low-temperature heat exchanger 4 can be cooled by being bypassed from the middle by the system 124. This makes it possible to compensate for heat intrusion into the low-temperature portion from the outside and cold heat loss due to the efficiency of the low-temperature heat exchanger 4.

It is also possible to short-circuit the working fluid of the system 101 directly to the low-temperature economizer 5 via the heat exchanger 4 without installing the expansion valve 12 and / or the second expander 7. In this case, the power storage efficiency is slightly reduced as compared with the case where the second expander 7 is provided, but the construction cost of the device can be reduced.

According to the first embodiment of the cryogenic power generation system using liquid air having the above-described configuration, the cooling operation of the liquid air by the above-described operation is introduced into another system without being discarded outside the thermodynamic cycle system. It moves to a fluid (air) and cools it to a very low temperature range. Therefore, since heat is transferred by heat exchange between air and air, the heat transfer is lower than that of a cold storage method in which heat is exchanged between solids and liquids and air, which have significantly different specific heat and other thermal properties. The subsequent temperature difference is also small, and therefore the exergy loss can be minimized according to the above equation (2).

The low-temperature heat source in the thermodynamic cycle includes cold generated during vaporization of liquid air (system number 10 in FIG. 1).
1 to 102) and the cold heat newly generated by the second expander 7 and the expansion valve 12 (system numbers 110 to 111 and 102 to 102).
111), and the air (system numbers 121 to 122) introduced from the atmosphere is cooled in another system by the cold heat.

The liquid air of the system number 101 becomes gaseous air at an intermediate portion of the low-temperature heat exchanger 4, for example, about 50% is extracted, and is led to the low-temperature side of the low-temperature heat exchanger 4 again through the expansion valve 12. I will Further, the remaining 50% of the air is further heated on the high temperature side of the low temperature heat exchanger 4, then its temperature is reduced by the second expander 7, and is again introduced into the intermediate portion of the low temperature heat exchanger 4 and expanded. It merges with the air coming from the valve 12, passes through the high temperature section of the low temperature heat exchanger 4, and reaches the low temperature economizer 5.

Thus, the liquid air of system number 101 is
This means that ultra-low temperature exergy of about 1.5 times the initial value is given by the newly generated cold heat in the process of reaching the system number 111.

Therefore, the amount of air introduced into the separate systems 121 to 122 from the atmosphere is equivalent to the system number 10
More than 1.5 times as much as the liquid air of 1 is required, and after being compressed at an extremely low temperature, it is sent to the system number 123.

Finally, the amount of air (working fluid) that can be supplied to the internal combustion engine 10 is 2.5 times or more, which is the sum of the system numbers 123 and 111.

This is similar to the example of a water pump that draws a large amount of water using just a small amount of priming water. In other words, it can be expressed as priming utilizing the characteristics of liquid air. Due to the priming use of liquid air, the working fluid of the thermodynamic cycle has a capacity of about 2.5 times or more in the state of the ultra-low temperature liquid and the dense air in the pump 3 and the first fluid.
Since the pressure is increased from an extremely low temperature by the compressor 9, the compression work of the thermodynamic cycle is significantly reduced as compared with the compression operation from room temperature.

In general, in a thermodynamic cycle of a gas turbine or the like, about 60% of the engine output is consumed as the compression work of the cycle working fluid, so that the heat efficiency of the cycle is reduced. In the thermodynamic cycle of a cryogenic power generation system using air, as described above, in addition to being able to suppress the loss of ultra-low temperature exergy, the compression work of the cycle is significantly improved by priming use of liquid air. Since the output is also added, the power (power) storage efficiency defined later is set to 100% or more.

Next, a second embodiment of a cryogenic power generation system using liquid air according to the present invention will be described with reference to FIG. The same components as those in the first embodiment are denoted by the same reference numerals.

In the thermal power generation system using liquid air shown in FIG. 3, the volume of air is reduced by preliminary compression by the third compressor 13 before introducing air into another system in the thermodynamic cycle. After that, the system is supplied to the cycle, and the other configuration is the same as that of the first embodiment. According to such a method, a preliminary compression power at room temperature is required, so that the compression work of the cycle slightly increases as compared with the embodiment shown in FIG. Wet / de-C
The O ₂ device 8 and the low-temperature heat exchanger 4 can be reduced in size.

Next, a third embodiment of a cryogenic power generation system using liquid air according to the present invention will be described with reference to FIG. Also in the present embodiment, the same reference numerals are given to the same components in the drawings.

The cryogenic power generation system using liquid air shown in FIG. 4 is different from the first and second embodiments in that a separate system for introducing air from the atmosphere is used as a closed system to introduce air from outside. Instead, a first expander 14 is newly provided in this closed system, and a system number 120-1 is provided.
21-122-123-120 is a closed cycle system in which a working fluid is circulated in this system to perform the same operation as in the first and second embodiments. 1 and 2 are the same as those of the second embodiment, and a detailed description thereof will be omitted.

In the third embodiment, the circulating working fluid performs most of the work in the first expander 14 instead of the internal combustion engine 10, and the generator 15 generates electric power. The expander 14 may communicate with the generator 11, in which case the generator 15 is not needed.

In the case of the third embodiment, the first and second
Although the number of the first expanders 14 to be installed increases as compared with the embodiment, the dehumidification / de-CO ₂ device is not required, and the entire device can be downsized. In addition, as the working fluid circulating in the closed cycle, nitrogen, argon, freon, or the like can be used in addition to air.

According to the present invention, the pressure of 8
By cooling the working fluid with very low to low temperature liquid air or low temperature gas air in the temperature range of 0 to 250 K, the compression work required for the operation of compressing the working fluid is significantly reduced, and the electric power stored in the liquid air can be re-used. The conversion recovery rate is improved, and the storage efficiency can be improved and energy saving can be achieved.

Next, a fourth embodiment of a cryogenic power generation system using liquid air according to the present invention will be described with reference to FIG. Also in the present embodiment, the same components are denoted by the same reference numerals in the drawings, and detailed description is omitted.

The cryogenic power generation system using liquid air shown in FIG. 5 is different from the first, second, and third embodiments in that the inlet pressure of the second expander 7 is increased to 15 MPa or more. The temperature of the working fluid at the outlet of the expander 7 is lowered to a lower temperature and introduced into the lower temperature side of the heat exchanger 4, and the expansion valve 12 is not installed. That is, when the expansion valve 12 is not installed, the expander 7 is operated at a low pressure.
If the inlet pressure of the first heat exchanger 4 is low, it is difficult to balance the temperature of the heat exchanger 4. However, by increasing the inlet pressure of the first expander 7, the temperature balance can be stabilized. FIG. 6 shows a TS diagram when such a configuration is employed. As can be seen from FIG. 6, the power recovery is increased by an amount corresponding to the increase in the inlet pressure of the second expander 7, and the power recovery efficiency is improved.
The amount of cold generated can also be increased.

Here, if the power storage efficiency (%) = reconversion recovered power amount / required power amount during storage × 100 (A), the required power amount during storage is equivalent to the production of liquid air. The required power consumption corresponds, and the liquid air is converted to the standard state from the practical design data of the cryogenic air separation device,
It is about 0.5 to 0.8 kwh / m ³ _N. In addition, when a trial calculation is performed using a diesel engine as the internal combustion engine 10 and practical data is used, the value of the above equation (A) is about 120
% Values are obtained.

This 120% does not mean an increase in energy. By combining the thermodynamic cycle of the present invention with a conventional diesel engine generator, the thermal efficiency is improved, and the recovery is equivalent to the improvement. This indicates that the amount of power consumed exceeds the amount of power required for storage. In other words, as compared with the power generation efficiency of the conventional diesel engine power generation device, the amount of conversion into electric power contributed by the energy saving improvement according to the present invention is 120% of the required power amount during storage. Thereby, the power storage efficiency is 10
0% or more is ensured, and further energy saving can be achieved. According to the present invention, it is possible to simultaneously improve the efficiency of stored power and save energy.

[0057]

As is clear from the above description, according to the cryogenic power generation system using liquid air according to the present invention,
It has made it possible to minimize the loss of ultra-low-temperature exergy possessed by the cryogenic heat of liquid air, and to generate new cryogenic heat by utilizing the characteristics of liquid air as a prime water.

As a result, it is possible to improve the thermal efficiency of the power generation cycle by utilizing the cold energy of the liquid air, which has consumed a large amount of energy, several times as described above. By recovering and canceling most of the power required to produce liquid air by a considerable amount of the improvement in efficiency, 1
Power (power) storage efficiency of 00% or more can be achieved.

Further, in the present invention, since a cool storage mechanism is not required, the system has a simple configuration, and construction costs and operating costs required for operation and maintenance are reduced. This makes it easier to construct a technically and economically efficient power storage device close to the demand area, and to install small- to medium-sized power storage devices in a multi-pole distributed manner. It is also possible to contribute to load leveling of power demand.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a first embodiment of a cryogenic power generation system using liquid air according to the present invention.

FIG. 2 is a TS diagram of a working fluid in the cold electric power generation system using the liquid air of FIG.

FIG. 3 is a system diagram showing a second embodiment of a cryogenic power generation system using liquid air according to the present invention.

FIG. 4 is a system diagram showing a third embodiment of a cryogenic power generation system using liquid air according to the present invention.

FIG. 5 is a system diagram showing a fourth embodiment of a cryogenic power generation system using liquid air according to the present invention.

FIG. 6 is a TS diagram of the thermal power generation system of FIG. 5;

[Explanation of symbols]

1 liquid air production device 2 liquid air storage tank 3 pump 4 cold heat exchanger 5 a heating device (cold economizer) 6 heating device (high temperature economizer) 7 second expander 8 dehumidified and de CO ₂ device 9 first Compressor 9 'Second compressor 10 Internal combustion engine 11 Generator 12 Expansion valve 13 Third compressor 14 First expander 15 Generator M Motor

Claims (9)

[Claims] 1. A cold electric power generation system for driving an internal combustion engine by utilizing the exergy of liquid air to generate electric power, comprising: a pump for pumping liquid air; A heat exchanger to be exchanged, wherein the liquid air is vaporized by the heat exchanger, and the vaporized air is introduced into the internal combustion engine as combustion air. 2. An air for exchanging heat with the liquid air in the heat exchanger is introduced into the thermodynamic cycle from the atmosphere from a different system from a thermodynamic cycle system from the pump to the internal combustion engine. 2. The cryogenic power generation system according to claim 1, wherein after passing through the heat exchanger, the first compressor compresses and supplies the compressed air to the internal combustion engine as combustion air. 3. A structure in which a working fluid for exchanging heat with the liquid air in the heat exchanger circulates in a closed cycle different from a thermodynamic cycle system from the pump to the internal combustion engine, A second compressor that compresses the working fluid exiting the heat exchanger during a closed cycle, and a first compressor that expands the compressed working fluid to perform work for power generation.
2. The thermal power generation system according to claim 1, further comprising: an expander. 4. A second expander for causing the liquid air pumped from the pump to evaporate into pressurized air by the heat exchanger and then causing the pressurized air to perform work for power generation,
4. The thermal power generation system according to claim 1, wherein exhaust gas from the second expander is introduced again into the heat exchanger. 5. 5. The liquid air pumped from the pump,
In the heat exchange process in a temperature range of 273K or less, an expansion valve is provided for extracting and expanding a part of the air in a state of liquid air or gaseous air. The thermal power generation system according to any one of claims 1 to 4, wherein: 6. A third compressor for pre-compressing air introduced to a high temperature side of the heat exchanger for heat exchange with the liquid air before introducing the air into the heat exchanger. The thermal power generation system according to any one of claims 1 to 5, wherein 7. The thermoelectric generator according to claim 1, wherein the heat exchanger is arranged to exchange heat with the liquid air immediately after being discharged from the pump. system. 8. A heating device for heating the air introduced into the internal combustion engine and / or the working fluid circulating in the closed cycle to 374 K or more. Cold power generation system 9. The first compressor supplies combustion air supplied to the internal combustion engine to a temperature of 0.15 K in a temperature range of 220 K or less.
3. The cryogenic power generation system according to claim 2, wherein the pressure can be increased to 15 MPa.