KR102255155B1 - Combination Energy Hub System - Google Patents

Abstract

The present invention relates to a region-based combination energy hub system which is able to collect unused energy of a natural gas supply management station, supply the energy to an energy consumer, to associate with a region near the supply management station, and supply combination energy such as electric power, heat, hydrogen, and natural gas. In accordance with the present invention, the combination energy hub system comprises: an energy supply unit which produces two or more types of energy sources by using high-pressure natural gas transferred from a natural gas production base as a fuel; and an energy consumption unit which includes an energy consumption complex, which is a region which demands one or more of the two or more types of energy sources, and which receives and directly uses the energy sources produced by the energy supply unit or supplies a type of energy sources needed by another consumer. The energy supply unit includes: a constant pressure unit which reduces the pressure of the high-pressure natural gas to a pressure required by the natural gas consumer, and which converts the pressure-reducing energy into electric power and produces electric power; and a hydrogen fuel unit which produces hydrogen, electric power, and heat sources by using the low-pressure natural gas, whose pressure is reduced by the constant pressure unit, as the fuel. In addition, the energy supply unit is formed with the energy consumption complex as the base.

Description

Combined Energy Hub System

The present invention relates to a regional hub-type hybrid energy hub system that recovers unused energy from a natural gas supply management office and supplies it to an energy demanding point, and supplies complex energy such as power, heat, hydrogen, and natural gas in connection with an area near the supply management office. will be.

Fossil fuels such as coal and petroleum are traditional energy sources and are accompanied by problems such as environmental pollution and natural depletion, and the seriousness of the problem is increasing day by day. Efforts are being made to reduce the use of fossil fuels to solve the problem of environmental pollution around the world. The field in which the proportion of fossil fuels is used is in the electric power generation field, and the electric power supply in Korea is mainly achieved through thermal and nuclear power generation.

As described above, with the change in the energy paradigm according to the future energy conversion policy, the necessity of developing complex energy technologies such as clean energy and new renewable energy is increasing.

On the other hand, the power generation plant, which is the production site of electric power, tends to be intensively deployed in a specific area with suitable location conditions due to its characteristics. For this reason, the emission of air pollutants such as the concentration of warming gas and fine dust in a specific area where power plants are concentrated is overwhelmingly higher than in other areas.

In addition, fossil fuels are mainly used not only as fuel for power plants, but also directly as fuels for automobiles and airplanes, as well as industrial and domestic fuels. Although efforts are being made not only to reduce the use of fossil fuels as fuel for power generation, but also to increase the supply of electric vehicles and hydrogen vehicles, construction of infrastructure such as electric and hydrogen charging stations is still insufficient.

On the other hand, natural gas is one of the energy sources that emit less pollutants than LNG, and is generally stored and transported in a liquid state (LNG). After vaporization, it is decompressed and supplied from supply management offices scattered across the country to each city gas demand.

Domestic LNG production bases (acquisition bases) are sending natural gas at a pressure of about 60 to 65 bar, and more than 100 supply management offices at bases across the country use static pressure facilities to provide the necessary pressure to each power plant or city gas supply station. It is supplied under reduced pressure. At each supply station, the pressure is reduced to about 25 bar for power plants and about 8.5 bar for city gas supply.

In the supply management office, high-pressure natural gas is decompressed using a pressure reducing valve, and temperature loss occurs as the pressure of the natural gas decreases. When the high-pressure natural gas is depressurized, the ^{temperature per 1kg/cm 2} decreases by about 0.6℃. Due to the temperature loss due to this decompression, the temperature of natural gas may be lowered to below zero, and in this case, freezing problems of piping and equipment in the process after the decompression may occur.

In this way, the cold heat and decompression energy of natural gas generated while decompressing natural gas was not recovered and remained as unused energy that was discarded. An electric boiler is installed upstream of the pressure reducing valve to preheat the natural gas before depressurization, so that the temperature of the natural gas after depressurization is maintained above the proper temperature. Since power is not supplied to the back, the decompression facility is stopped, and natural gas cannot be supplied stably.

Accordingly, an object of the present invention is to provide a complex energy hub system based on a regional base-type integrated energy platform that supplies complex energy based on a natural gas supply management office in order to solve the above-described problems.

According to an aspect of the present invention for achieving the above object, the energy supply unit for producing at least two or more kinds of energy sources by using the high-pressure natural gas transferred from the natural gas production base as fuel; And an energy demand complex, which is an area that demands any one or more of the two or more energy sources, and uses the energy source produced by the energy supply unit directly or in a form required by another consumer. Including, the energy supply unit, the high-pressure natural gas is reduced to a pressure required by the natural gas consumer, and a constant pressure unit for converting the reduced pressure energy into electric power to produce electric power; And a hydrogen fuel unit for producing hydrogen, electric power, and a heat source by using the low-pressure natural gas depressurized by the positive pressure unit as fuel. Including, there is provided a complex energy hub system formed based on the energy demand complex.

Preferably, the positive pressure unit includes a preheater for preheating the waste heat discharged from the hydrogen fuel unit as a heat source before depressurizing the high pressure natural gas; And a decompression generator for converting decompression energy into electric power while decompressing the high-pressure natural gas preheated in the preheater.

Preferably, the hydrogen fuel unit, a hydrogen production unit for producing hydrogen by reforming the low pressure natural gas; And a fuel cell for generating electric power by using hydrogen produced by the hydrogen production unit as fuel, and a first heat source line for transferring waste heat discharged from the fuel cell to the preheater.

Preferably, the energy demand unit may include a hydrogen-electric charging station for charging hydrogen and electric power generated by the energy supply unit as vehicle fuel.

Preferably, the hydrogen-electric charging station may further include a control center that controls whether or not the energy supply unit is operated and the operating load according to the amount of hydrogen and power demanded.

Preferably, the static pressure unit may be a supply management station in which the reduced pressure natural gas is used as city gas.

Preferably, the energy demanding unit includes; a cogeneration unit that generates electric power using the natural gas depressurized by the static pressure unit, wherein the cogeneration unit, the exhaust gas generated by burning the natural gas as a working fluid A gas turbine that generates electric power by using it; A waste heat boiler that produces steam from waste heat discharged from the gas turbine; And a steam turbine generating electric power by using the steam generated by the waste heat boiler as a working fluid.

According to another aspect of the present invention for achieving the above object, the energy supply unit for producing at least two or more types of energy sources including electric power by using the high-pressure natural gas transferred from the natural gas production base as fuel; And an energy demand unit that requires any one or more of the two or more energy sources produced by the energy supply unit in combination, but is installed in the energy supply unit to depressurize the high-pressure natural gas and recover reduced pressure energy. A positive pressure unit for generating electric power; A hydrogen fuel unit installed in the energy supply unit to produce hydrogen by reforming the natural gas depressurized by the constant pressure unit and to generate electric power by using the hydrogen as fuel; And a cogeneration unit installed in the energy demand unit and configured to drive a turbine using natural gas depressurized by the static pressure unit as fuel and recover kinetic energy of the turbine to generate electric power; including, the static pressure unit, hydrogen Including; a power distribution unit that directly supplies power produced by at least three power generation sources including a fuel unit and a cogeneration unit to a power demand source, or stores power in a power storage device and supplies the stored power to a power demand source; , A hybrid energy hub system for distributed generation based on the power demand point is provided.

Preferably, a first heat source line for transferring the heat source discharged from the hydrogen fuel unit to a heat source customer; And a third heat source line for transferring the heat source discharged from the cogeneration unit to a heat source consumer, wherein the heat source consumer may include the energy demanding unit and the static pressure unit.

Preferably, the energy demanding unit includes: an electric vehicle charging station for charging electric power to an electric vehicle driven by using the generated electric power as an energy source; And a hydrogen vehicle charging station for charging hydrogen into a hydrogen vehicle driven by using hydrogen produced by the hydrogen fuel unit as an energy source.

The hybrid energy hub system of the present invention can establish a complex energy network with high degree of independence by integrating various power generation sources and heat source supply sources by utilizing unused energy of the supply management office.

In addition, according to the central power supply method, it was inefficient due to equipment problems, power loss problems, frequent energy conversion, etc. due to long-distance transmission/distribution from a power plant to a demand site, but according to the present invention, by securing a complex energy supply base, the energy supply source It is possible to integrate energy and demands over a short distance, and to supply energy efficiently according to load tracking.

In addition, by establishing a distributed power source for each region, it is possible to supply a variety of energy, such as power, cold and hot heat, hydrogen, natural gas, etc., required by energy consumers through energy conversion of the primary energy source, thereby improving the energy self-sufficiency rate, intermittentity, and The efficiency of the fusion process can be improved through synergy between systems through process linkage with natural gas according to the characteristics of renewable energy generation according to ubiquity.

In addition, due to the asymmetry between the energy supply source and the consumer, it is possible to solve the extreme problem of environmental pollution in an area where the energy supply source is concentrated.

In addition, hydrogen charging stations and electric charging station infrastructure can be constructed with low cost and high efficiency, thus contributing to the promotion of the supply of hydrogen and electric vehicles.

1 is a schematic diagram illustrating a process concept of a hybrid energy hub system according to an embodiment of the present invention.
2 is a schematic diagram illustrating an arrangement concept of a hybrid energy hub system according to an embodiment of the present invention.
3 is a diagram illustrating a process simulation modeling of an energy supply unit of a hybrid energy hub system according to an embodiment of the present invention simulated using a program.

In order to fully understand the operational advantages of the present invention and the object achieved by the implementation of the present invention, reference should be made to the accompanying drawings illustrating preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, the configuration and operation of a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Here, in adding reference numerals to elements of each drawing, it should be noted that only the same elements are marked with the same numerals as possible, even if they are indicated on different drawings.

The following examples may be modified in various different forms, and the scope of the present invention is not limited to the following examples.

Hereinafter, a hybrid energy hub system according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

The hybrid energy hub system according to the present invention includes an energy supply unit (ES) for producing at least two types of energy by using high-pressure natural gas transferred from a natural gas production base as fuel; And an energy demand unit (ER) that receives and directly uses the energy produced by the energy supply unit (ES) or supplies energy in a type required by each consumer.

In addition, the hybrid energy hub system of this embodiment is provided in connection with any one or more energy demand complexes 800, as shown in FIG. 2.

In this embodiment, the energy demand complex 800 is a residential complex in which residential facilities such as apartments are concentrated, a commercial complex in which daily convenience facilities such as convenience stores and marts are concentrated, offices, hospitals, etc., in which office or industrial facilities are concentrated. It refers to an industrial complex in which industrial facilities such as industrial complexes, industrial plants, and power plants are concentrated, and a complex in which any two or more of residential, commercial, industrial and industrial facilities are concentrated.

The energy supply unit (ES) according to the present embodiment includes: a static pressure unit 100 for supplying the high-pressure natural gas transferred from the natural gas production base to a pressure required by the natural gas customer at a constant pressure to the natural gas customer; And a hydrogen fuel unit 200 for producing hydrogen and electric power by using the low pressure natural gas reduced by the positive pressure unit 100 as fuel.

The static pressure unit 100 of this embodiment includes a preheater 110 for preheating the high-pressure natural gas transferred from the natural gas production base along the high-pressure gas line GL1 before depressurizing it; And a decompression generator 120 for decompressing the high-pressure natural gas preheated by the preheater 110 to a pressure required by the natural gas consumer, and converting the decompressed energy into electric energy while depressurizing the natural gas.

The heat source for heating the high-pressure natural gas in the preheater 110 may be waste heat recovered from the energy supply unit ES. According to this embodiment, waste heat discharged from the hydrogen fuel unit 200 to be described later is transferred to the preheater 110 along the first heat source line QL1, and in the preheater 110, the first heat source line QL1 is High-pressure natural gas is heated by the waste heat of the hydrogen fuel unit 200 transferred to the preheater 110 through the preheater 110, and the waste heat is cooled and discharged.

The high-pressure natural gas heated in the preheater 110 is transferred to the decompression generator 120 along the high-pressure gas line GL1. The waste heat cooled in the preheater 110 may be discharged to the outside or may be transferred to the energy demanding unit ER to be used as a heat source.

The decompression generator 120 of the present embodiment may be applied as a means for expanding a gas, and an expansion means using a Joule-Thomson effect in which the temperature of the gas is lowered during adiabatic expansion. Natural gas, when depressurized by the isentropy process by the Joule-Thomson effect, is reduced by about 10°C per 10 bar, and when depressurized by the isoenthalpy process, it is reduced by about 5°C per 10 bar.

In this embodiment, the decompression generator 120 may be an expander in which fluid expands through an isentropic process, and may be, for example, a Turbo Expander Generator (TEG) that generates electric energy using reduced pressure energy.

The pressure reducing generator 120 may be an expansion valve through which a fluid is depressurized by an isoenthalpy process. When the expansion valve is applied to the pressure reducing generator 120, there is an advantage in that the cost is low, occupies a small space, and the temperature drop is small, but there is a disadvantage in that the reduced pressure energy cannot be recovered.

In this embodiment, it is preferable that the reduced pressure generator 120 is an expander equipped with a generator. In the static pressure facility, the expander is expensive, and when it is actually applied, it is evaluated for its low economic efficiency due to the small amount of electricity produced compared to the investment. However, according to the present embodiment, since it is possible to recover waste heat to preheat natural gas and to recover the reduced pressure energy of natural gas while increasing the power output at low cost in connection with various power generation sources, it is possible to overcome the disadvantage of low economic efficiency. have.

In this embodiment, the pressure of the natural gas transferred to the static pressure unit 100 through the high-pressure gas line GL1 may be 60 bar to 65 bar, preferably about 55 bar. In addition, the pressure of the natural gas depressurized by the positive pressure unit 100, that is, the target pressure for decompression, may be about 25 bar, about 8.5 bar, or about 5 bar, or about 1 bar, although different depending on the demand for the natural gas.

In the present embodiment, the natural gas demand source may be a district pressure regulator or a regional pressure regulator, which is a city gas supply station, or may be an energy demand complex 800 that directly receives city gas.

For example, if a high-pressure natural gas of 55 bar is decompressed to 8.5 bar using the decompression generator 120, the temperature of the natural gas may be lowered to below zero, and low temperature damage to the pipes and equipment of the process after the decompression generator 120 Can cause.

Accordingly, according to the present embodiment, a preheater 110 is provided for heating the high-pressure natural gas to be depressurized upstream of the decompression generator 120 so that the temperature after the decompression is equal to or higher than a set temperature. Here, the set temperature may be, for example, a temperature exceeding 0° C. or a temperature of a condition required by the natural gas consumer 400.

In this embodiment, the flow rate of natural gas transferred to the static pressure unit 100 along the high-pressure gas line GL1 may be about 26 ton/hr or more.

Electric output produced by the reduced pressure generator 120 of this embodiment may be about 1.5 MWe.

In FIG. 1, the pressure-reducing generator 120 is provided as an example, but two or more pressure-reducing generators 120 are provided in series, so that high-pressure natural gas can be reduced to a target pressure in two or more steps. There will be.

The low-pressure natural gas depressurized by the decompression generator 120 is transferred to the natural gas consumer through the first low-pressure gas line GL2, and the power produced by the decompression generator 120 is described later through the first power line EL1. It may be transferred to the power distribution unit 700 or directly transferred to a power demand destination such as the energy demand complex 800.

The hydrogen fuel unit 200 according to the present embodiment includes a hydrogen production unit 210 for producing hydrogen by using the low-pressure natural gas decompressed in the decompression generator 120 as fuel; And a fuel cell 220 that generates electric power by using hydrogen produced by the hydrogen production unit 210 as fuel.

Some or all of the low-pressure natural gas depressurized by the decompression generator 120 is transferred to the hydrogen production unit 210 through the second low-pressure gas line GL3.

The hydrogen production unit 210 of this embodiment includes a reformer (not shown) for producing hydrogen by reforming _{natural gas, that is, methane (CH 4 );} And a hydrogen purification apparatus (not shown) for purifying hydrogen produced in the reformer with high purity.

The reformer may be, for example, SMR (Stema Methane Reformer), by reforming the steam produced in the cogeneration unit 300 of the energy demanding unit (ER) to be described later and the natural gas decompressed in the decompression generator 120. It can produce hydrogen.

The hydrogen retention device may be a device for purifying hydrogen contained in by-product gas discharged from the reformer with high purity by, for example, a pressure swing adsorption (PSA) method.

Hydrogen produced by the hydrogen production unit 210 is supplied to the fuel cell 220 through the first hydrogen line HL1 or transferred to the hydrogen charger 500 of the energy demanding unit ER through the second hydrogen line HL2. Can be.

In addition, although FIG. 1 illustrates that one fuel cell 220 is provided as an example, one or more fuel cells 220 of the present embodiment may be provided. For example, in the present embodiment, two 400 kWe fuel cells 220 are provided as an example.

The power produced by the fuel cell 220 of the present embodiment may be transferred to the power distribution unit 700 through the second power line EL2 or may be directly transferred to a power consumer such as the complex 800.

In addition, waste heat discharged from the fuel cell 220 is transferred to the preheater 110 through the first heat source line QL1, and may be used as a heat source for preheating high-pressure natural gas. In addition, the waste heat discharged from the fuel cell 220 may be transferred through the second heat source line QL2 and used as a heat source for heating and cooling in a heat source consumer of the energy demanding unit ER, for example, the complex 800.

Waste heat discharged from the fuel cell 220 may be about 150°C.

In the hydrogen fuel unit 200 of the present embodiment, the operation rate may be controlled according to the amount of power demanded by the power demander, the amount of heat source demanded by the static pressure unit 100, and the amount of hydrogen demanded by the hydrogen demander 500.

On the other hand, when the hydrogen consumer 500 is a hydrogen charging station, if the hydrogen production amount of the hydrogen fuel unit 200 can be continuously maintained, the operation rate of the hydrogen charging station is also increased. Stable supply of hydrogen fuel from the hydrogen charger 500 to the hydrogen fuel vehicle is possible through continuous operation using a high operation rate.

The energy demanding unit ER of this embodiment includes a natural gas demanding unit 400 receiving natural gas from the energy supplying unit ES; A hydrogen consumer 500 receiving hydrogen from the energy supply unit ES; Power demanders 600 and 700 receiving power from the energy supply unit ES; An energy demand complex 800 receiving natural gas, hydrogen, power and heat sources from the energy supply unit ES; A cogeneration unit 300 for generating electric power by receiving natural gas from the energy supply unit ES; And other energy generation unit 900 for generating electric power by using renewable energy. It includes any one or more of.

The hydrogen consumer 500 according to the present embodiment may be a hydrogen charger 500 capable of charging hydrogen fuel with a hydrogen fuel vehicle using hydrogen as a fuel. 1 shows that only one hydrogen charger 500 is provided, but one or more hydrogen chargers 500 may be installed.

In addition, the hydrogen charger 500 of the present embodiment may be in the form of a package that is easy to detach and move, and an off-site method in which hydrogen is supplied from the energy supply unit ES through the second hydrogen line HL2. It may be a hydrogen charger 500 of.

Although not shown in the drawing, the hydrogen charger 500 includes a flow rate measuring unit (not shown) that measures the flow rate of hydrogen transferred to the hydrogen fuel vehicle, and a nozzle that injects hydrogen into the hydrogen fuel tank of the hydrogen fuel vehicle (not shown). City) and a breakaway (not shown), which is a safety device provided to separate the nozzle and hose assembly without damage to parts when an external shock occurs during hydrogen charging into the hydrogen fuel vehicle.

The power demand destination of this embodiment is the power generated by the reduced pressure generator 120 of the energy supply unit (ES), the fuel cell 220, the cogeneration unit 300 of the energy demand unit (ER), and other energy production units 900. It may include; a power distribution unit 700 for receiving and storing or distributing and supplying it to each consumer.

The power distribution unit 700 may include a power storage device 710 that stores surplus power and supplies the stored power to each consumer when the power peaks.

In addition, the power demand destination may be an electric charger 600 capable of charging electric power with an electric vehicle. 1 shows that only one electric charger 600 is provided, but one or more electric chargers 600 may be installed, and in this embodiment, three rapid electric chargers 600 are installed as an example. I will explain.

The cogeneration unit 300 of this embodiment receives the low-pressure natural gas depressurized by the decompression generator 120 through the third low-pressure gas line GL4, and uses the low-pressure natural gas as a fuel to produce power and heat sources. have.

The cogeneration unit 300 includes a gas turbine (not shown) that generates electric power by using exhaust gas generated by burning natural gas as a working fluid; A waste heat boiler (not shown) that produces steam from waste heat discharged from the gas turbine; And a steam turbine (not shown) that generates electric power using steam produced by the waste heat boiler as a working fluid.

The power produced by the cogeneration unit 300 may be supplied to the power distribution unit 700 through the third power line EL3, or may be directly supplied to each power consumer.

In addition, the heat source discharged from the cogeneration unit 300 may be supplied to a heat source consumer, that is, the energy demand complex 800 in this embodiment through the third heat source line QL3. In addition, although not shown in the drawing, the heat source discharged from the cogeneration unit 300 may be supplied to the preheater 110 of the static pressure unit 100, or to be supplied to the hydrogen production unit 210 of the hydrogen fuel unit 200. It might be possible.

The heat source discharged from the cogeneration unit 300 is exhaust gas generated by combustion of natural gas, steam produced in a waste heat boiler, gas turbine exhaust gas discharged after driving the gas turbine, or discharged after driving the steam turbine. It may be steam turbine condensate.

The cogeneration unit 300 of the present embodiment serves as an energy supply unit (ES) for generating energy, but is disposed in the energy demand unit (ER) in order to safely operate the positive pressure unit 100.

Other energy production unit 900 of the present embodiment may be a renewable energy generation source such as solar energy, wind power generation.

Other electric power produced by the energy production unit 900 may be transferred to the power distribution unit 700 along the fourth power line EL4 or may be directly transferred to each power demand.

Energy such as natural gas, electric power, hydrogen, and heat generated in this embodiment can be used not only in the energy demand unit ER, but also as energy required to drive the device in the energy supply unit ES.

The hybrid energy hub system according to the present embodiment includes at least three or more power generation sources, such as a depressurization generator 120, a fuel cell 220, a cogeneration unit 300, and other energy generation units 900, as described above. And, it can produce at least two or more types of energy sources such as natural gas, hydrogen, heat source, and electric power.

In addition, the hybrid energy hub system according to the present embodiment may further include a control center (CR). The control center (CR) is a means for controlling the operation and load of each device included in the hybrid energy hub system, distributing and supplying the produced energy to the demanders that require it, and controlling the amount of energy supply to each demander. Can be

Next, referring to FIG. 3, the amount of power produced according to the present embodiment will be described with reference to numerical values simulated using a process simulation computer modeling program as an example. In one embodiment of the process simulation described below, the temperature, pressure, flow rate, and power output at each point are only exemplary values for explaining the effect of improving power efficiency according to the present embodiment, and the effect of the present invention is limited thereto. It is not.

First, the device referred to as'Heater 1'in FIG. 3 corresponds to the preheater 110 of FIG. 1, and the device referred to as'FCP' of FIG. 3 corresponds to the fuel cell 220 of FIG. The device referred to as'CHP' of FIG. 1 corresponds to the cogeneration unit 300 of FIG. 1, and the device referred to as '1st MTG' of FIG. 3 corresponds to the reduced pressure generator 120 of FIG. 1.

However, in Fig. 1, the preheater 110 and the decompression generator 120 are shown as being configured in one stage, but in the process simulation of Fig. 3, two preheaters 110 and two decompression generators 120 are provided in series. It was carried out as an example that was composed of two stages.

That is, in FIG. 3,'Heater 1'and '1st MTG' are the first stage preheater 110 and the first stage decompression generator 120, respectively, and'Heater 2'and '2nd MTG' are respectively the second stage preheater 110 and It means a two-stage decompression generator 120.

The pressure of the high-pressure natural gas supplied to the first stage preheater (heater 1, 110) through the first point of FIG. 3, that is, the high-pressure gas line GL1 of FIG. 1 is 60 bar, the temperature is 30°C, and the flow rate is 25 ton. Process simulation was performed in the case of /hr.

According to this embodiment, the pressure of the high-pressure natural gas heated at the second point, that is, the first stage preheater (heater 1, 110) is 60 bar and the temperature is 65°C.

The pressure of the depressurized and cooled natural gas at the third point, that is, the first stage decompression generator (1st MTG, 120) is 25 bar, and the temperature is 5.5°C.

The fourth point, that is, the pressure of the high-pressure natural gas heated in the two-stage preheater (heater 2, 110) is 25 bar and the temperature is 65°C.

The fifth point, that is, the pressure of the natural gas depressurized and cooled in the two-stage decompression generator (2nd MTG, 120) is 8.7 bar, and the temperature is 3.6°C.

Here, energy (HT1) consumed by the first stage preheater (heater 1, 110) to heat natural gas at 60 bar and 30°C to 65°C is 602.2kW, and natural gas at 25 bar and 5.5°C to 65°C. Energy (HT2) consumed by the two-stage preheater (heater 2, 110) for heating is 972.3kW, a total of 1574.5kW (=602.2kW+972.3kW).

In addition, the power produced by decompressing natural gas in the first stage decompression generator (1st MTG, 120) is 707 kWe, and the power produced by decompressing natural gas in the second stage decompression generator (2nd MTG, 120) is 843 kWe. It is 1550 kWe.

At this time, when only the decompression generator 120 is applied without linking the decompression generator 120 with the fuel cell 220 and the cogeneration unit 300, a total of 1550 kWe of electric power is produced while preheating natural gas. In order to do so, a total of 1574.5kW of heat source is consumed, so it is very uneconomical in terms of the total energy balance.

However, in the case of constructing a composite energy system as in this embodiment, a heat source of 862 kW is recovered from the fuel cell 220, and a heat source of 340.5 kW is recovered from the cogeneration unit 300, and the heat source required for preheating natural gas. While alternatively used, the fuel cell 220 can produce 790 kWe and the cogeneration unit 300 can additionally produce 200 kWe of electricity, and thus, when calculating the total energy balance, energy production efficiency is significantly increased. It can be seen that it is improved.

It is obvious to those of ordinary skill in the art that the present invention is not limited to the above embodiments, and can be implemented with various modifications or variations within the scope not departing from the technical gist of the present invention. I did it.

ES: Energy supply department
100: positive pressure part 200: hydrogen fuel part
110: preheater 210: hydrogen production unit
120: decompression generator 220: fuel cell
ER: Energy demand department
300: cogeneration unit 700: power distribution unit
400: natural gas consumer 710: power storage device
500: hydrogen charger 800: energy demand complex
600: electric charger 900: other energy generating unit
CR: Control center
GL1: high pressure gas line GL2: first low pressure gas line
GL3: second low pressure gas line GL4: third low pressure gas line
HL1: first hydrogen line HL2: second hydrogen line
EL1: first power line EL2: second power line
EL3: 3rd power line EL4: 4th power line
QL1: 1st heat source line QL2: 2nd heat source line
QL3: 3rd heat source line

Claims (10)

An energy supply unit for producing at least two types of energy sources by using the high-pressure natural gas transferred from the natural gas production base as fuel; And
Including; an energy demand unit that receives the energy source produced by the energy supply unit and directly uses it or supplies an energy source in a form required by another customer.
The energy supply unit,
A positive pressure unit for reducing the high-pressure natural gas to a pressure required by a natural gas consumer and converting the reduced pressure energy into electric power to generate electric power; And
Including; a hydrogen fuel unit for producing hydrogen, electric power and heat source by using a part or all of the low pressure natural gas depressurized by the positive pressure unit as fuel,
The energy demand unit,
A natural gas consumer receiving the pressure-reduced natural gas from the static pressure unit;
A cogeneration unit for generating electric power and thermal energy by using some or all of the low pressure natural gas reduced by the positive pressure unit as fuel; And
Including; an energy demand complex that requires an electric power and heat source, and includes any one or more of a residential complex, a commercial complex, an industrial complex, an industrial complex, and a complex.
The natural gas depressurized in the static pressure unit is supplied to one or more of the natural gas consumer, the hydrogen fuel unit, and the cogeneration unit,
The energy supply unit is formed based on the energy demand complex for distributed generation, and the energy demand complex receives and uses the power and heat source generated by the energy supply unit. The method according to claim 1,
The positive pressure part,
A preheater for preheating by using waste heat discharged from the hydrogen fuel unit as a heat source before depressurizing the high-pressure natural gas; And
Containing, a composite energy hub system including; a decompression generator for converting decompression energy into electric power while decompressing the high-pressure natural gas preheated in the preheater. The method according to claim 2,
The hydrogen fuel part,
A hydrogen production unit for producing hydrogen by reforming the low pressure natural gas; And
Including; a fuel cell for generating electric power by using the hydrogen produced by the hydrogen production unit as fuel,
A first heat source line for transferring waste heat discharged from the fuel cell to the preheater; further comprising, a hybrid energy hub system. The method of claim 3,
The energy demand unit,
A hydrogen-electric charging station for charging hydrogen and power generated by the energy supply unit as vehicle fuel; including, a hybrid energy hub system. The method of claim 4,
A control center for controlling whether or not the energy supply unit is operated and the operating load according to the amount of hydrogen and power demand of the hydrogen-electric charging station; further comprising, a hybrid energy hub system. The method according to claim 1,
The static pressure unit is a supply management station in which the reduced pressure natural gas is used as city gas, a hybrid energy hub system. The method according to claim 1,
The cogeneration unit may include a gas turbine generating electric power using exhaust gas generated by burning the natural gas as a working fluid;
A waste heat boiler that produces steam from waste heat discharged from the gas turbine; And
Containing, a combined energy hub system; a steam turbine that generates electric power by using the steam generated by the waste heat boiler as a working fluid. delete The method according to claim 1,
A first heat source line for transferring the heat source discharged from the hydrogen fuel unit to a heat source consumer; And
Including; a third heat source line for transferring the heat source discharged from the cogeneration unit to a heat source customer,
The heat source demand source is,
A hybrid energy hub system comprising the energy demanding unit and the static pressure unit. The method according to claim 1,
The energy demand unit,
An electric vehicle charging station for charging electric power to an electric vehicle driven by using the generated electric power as an energy source; And
Containing, a hybrid energy hub system comprising; a hydrogen vehicle charging station for charging hydrogen into a hydrogen vehicle driven by using the hydrogen produced by the hydrogen fuel unit as an energy source.

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