ENERGY SYSTEM AND METHOD FOR PRESSURE ADJUSTMENT IN AN ENERGY SYSTEM

Abstract

The invention relates to an energy system (10) and a method for adjusting the line pressure in an energy system (10). The energy system (10) comprises a first energy source unit (21), a first energy sink unit (22), a second energy source unit (31) and a connection line unit (40), via which the first energy source unit (21) is connected to the second energy source unit (31) and the second energy source unit (31) is connected to the first energy sink unit (21). In order to reduce, as far as possible, the number of components in the energy system (10), preferably also the number of line sections of the connection line unit (40) required for different operating modes of the energy system (10) with different pressure levels, according to the invention, at least individual sections of the connection line unit (40) are designed as bidirectional line sections (40a to 40e) and the connection line unit (40) is connected to a pressure adjustment unit (50), which is provided in such a way that it can set a direction-dependent pressure level in the bidirectional line sections (40a to 40e) of the connection line unit (40).

Claims

1. An energy system (10), in particular a house energy system, comprising a first energy source device (21), a first energy source device (22), a second energy source device (31), and a connecting line device (40), by means of which the first energy source device (21) to the second energy source device (31) and the second energy source device (31) to first energy sink device (21) are connected to each other, characterized in that at least individual sections of the connecting line device (40) are configured as bidirectional line sections (40a to 40e), via which a flow takes place in both directions during operation of the energy system, and in that the connecting line device (40) is connected to at least one pressure adaptation device (50), which is provided in such a way that it is capable to set a direction-dependent pressure level in the bidirectional line sections (40a to 40e) of the connecting line device (40).

2. The energy system according to claim 1, characterized in that the energy system (10) comprises a second energy sink device (32) which is connected via a valve device (33) to the connecting line device (40).

3. The energy system according to claim 1, characterized in that the first energy source device (21) is configured as an electrolysis device, in particular for producing hydrogen, and/or in that the first energy sink device (22) is configured as a fuel cell device and/or in that the second energy source device (31) is configured as high-pressure storage device, in particular for storing hydrogen, and/or in that the second energy sink device (32) is configured as a medium-pressure storage device, in particular for intermediary storing hydrogen.

4. The energy system according to claim 1, characterized in that the pressure adaptation device (50) is configured as a device for reducing pressure in the bidirectional line sections (40a to 40e) of the connecting line device (40).

5. The energy system according to claim 1, characterized in that the pressure adaptation device (50) comprises a compressor device (34) which is provided in the connecting line device (40) and which is connected to a storage device, in particular to the second energy storage device (31), and in that the compressor device (34) is, in particular, at the same time that compressor device (34) which is used to load the second energy source device (31).

6. The energy system according to claim 1, characterized in that the pressure adaptation device (50) is configured as an additional expansion volume which is connected via a valve device to the connecting line device (40), and in that the additional expansion volume is preferably greater than the volume of the connecting line device (40), in particular as the volume of the bidirectional line sections (40a to 40e) of the connecting line device (40).

7. The energy system according to claim 1, characterized in that the energy system comprises a purging device (23) which is provided in such a way that it is capable of purging the first energy source device (21) and/or the first energy sink device (22), and in that the purging device (23) functions as the pressure adaptation device (50) and is connected to the connecting line device (40), in particular to the bidirectional line sections (40a to 40e) of the connecting line device (40), via a valve device.

8. The energy system according to claim 1, characterized in that at least one check valve device (24, 35) is arranged in the connecting line device (40), and in that the check valve device (24, 35) marks one end of a bidirectional line section.

9. The energy system according to claim 1, characterized in that at least one pressure measuring device (41) is assigned to the connecting line device (40), in particular to at least one bidirectional line section (40a to 40e) of the connecting line device (40).

10. A method of adapting the line pressure in a connecting line device of an energy system, in particular of a house energy system, wherein the energy system comprises a first energy source device, which is connected to a second energy source device via the connecting line device, and wherein the energy system comprises a first energy sink device, which is connected via the connecting line device to the second energy source device, characterized by the following steps: a) in a first mode of operation of the energy system, an energy provided by the first energy source device is transported at a first pressure via the connecting line device to the second energy source device and is stored there, wherein at least individual sections of the connecting line device are configured as bidirectional line sections, via which a flow takes place in both directions during operation of the energy system; b) in at least one second mode of operation of the energy system, energy provided by the second energy source device is supplied with a second pressure, which is different from the first pressure, via the bidirectional line sections of the connecting line device to the first energy sink device; c) depending on the mode of operation of the energy system, a direction-dependent pressure level in the bidirectional line sections of the connecting line device is set by means of a pressure adaptation device, which is connected to the connecting line device.

11. The method according to claim 10, characterized in that the method is performed in an energy system comprising: a first energy source device (21), a first energy source device (22), a second energy source device (31), and a connecting line device (40), by means of which the first energy source device (21) to the second energy source device (31) and the second energy source device (31) to first energy sink device (21) are connected to each other, characterized in that at least individual sections of the connecting line device (40) are configured as bidirectional line sections (40a to 40e), via which a flow takes place in both directions during operation of the energy system, and in that the connecting line device (40) is connected to at least one pressure adaptation device (50), which is provided in such a way that it is capable to set a direction-dependent pressure level in the bidirectional line sections (40a to 40e) of the connecting line device (40).

12. The method according to claim 10, characterized in that in the case of changing from the first mode of operation of the energy system to the second mode of operation of the energy system, the line pressure prevailing in the first mode of operation in the form of the first pressure in the bidirectional line sections is reduced to the line pressure in the form of the second pressure prevailing in the second mode of operation by means the pressure adaptation device, wherein in particular the volume being present at least in the bidirectional sections of the connecting line device is reduced by means of the pressure adaptation device.

13. The method according to claim 10, in which the energy system comprises a second energy sink device which is connected to the connecting line device via a valve device, characterized in that, in the first mode of operation of the energy system, the energy provided by the first energy source device with the first pressure is transported via the connecting line device to the second energy sink device and is intermediately stored there, and in that subsequently the energy intermediately stored in the second energy sink device is transported from there to the second energy source device and stored there.

14. The method according to claim 10, in which a compressor device is arranged in the connecting line device, characterized in that, in the first mode of operation of the energy system, energy which is provided by the first energy source device or energy that is intermediately stored with the first pressure is transported via the connecting line device to the compressor device and is stored via said compressor device in the second energy source device.

15. The method according to claim 14, characterized in that the compressor device functions as the pressure adaptation device, in that, depending on the mode of operation of the energy system, a direction-dependent pressure level is set in the bidirectional line sections of the connecting line device by means of the compressor device, and in that preferably in the event of a change from the first mode of operation of the energy system to the second mode of operation of the energy system, via the compressor device the line pressure prevailing in the first mode of operation in form of the first pressure in the bidirectional line sections is reduced to the line pressure prevailing in the second mode of operation in form of the second pressure in the bidirectional line sections, in that in particular volume being present in the connecting line device, is stored via the compressor device into the second energy source device until the second pressure is achieved in the bidirectional line sections of the connecting line device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The invention will now be explained in more detail with reference to an exemplary embodiment with reference to the accompanying drawings, wherein

[0059] FIG. 1 is a schematic view of an energy system according to the invention, in which the method according to the invention can be carried out;

[0060] FIG. 2 depicts the process of the method according to the invention, wherein a first mode of operation of the energy system is shown;

[0061] FIG. 3 depicts the process of the method according to the invention, wherein the transition between the first mode of operation of the energy system to a second mode of operation of the energy system is shown; and

[0062] FIG. 4 depicts the process of the method according to the invention, wherein the second mode of operation of the energy system is shown.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0063] FIGS. 1 to 4 show an energy system 10 which is used as a house energy system. In FIG. 1, the basic structure of the energy system 10 is first described. The method for pressure adaption according to the invention is performed in the energy system 10. The process flow in different modes of operation of the energy system 10 is explained with reference to FIGS. 2 to 4.

[0064] As can be seen from FIG. 1, energy system 10 initially comprises a first subsystem 20 which is configured as an inner system. That is, the first subsystem 20 is provided inside the house. In addition, the energy system 10 comprises a second subsystem 30 in the form of an outer system. That is, the second subsystem 30 is external to the house.

[0065] The first subsystem 20 comprises a first energy source device 21, which is an electrolysis device for producing hydrogen. In addition, the first subsystem 20 comprises a first energy sink device 22, which is a fuel cell device. The second sub-system 30 comprises a second energy source device 31, which is a high-pressure storage device. The hydrogen produced in the electrolysis device is stored in the high-pressure storage device at up to 700 bar. In addition, the second subsystem 30 comprises a second energy sink device 32 in the form of a medium-pressure storage device, in which the hydrogen produced is temporarily stored at pressures between 20 and 60 bar, before it gets finally stored by the high-pressure storage device.

[0066] The individual components of the energy system 10 are connected to one another via a connecting line device 40, which consists of a number of different line sections 40a to 40k. A first number of line sections 40a to 40e are designed as so-called bidirectional line sections. That means that these line sections 40a to 40e get flown through in both directions during operation of the energy system 10.

[0067] For purging the first energy source device 21 and/or the first energy sink device 22, a purging system 32 with a purge chamber is provided, which is connected via line section 40g to the two components mentioned before.

[0068] The hydrogen produced in the first energy source device 21 by means of electrolysis leaves the first energy source device 21 via a line section 40f, which passes over in bidirectional line section 40e. In both line sections 40f and 40e, in the flow direction of the produced hydrogen, a check valve device 24 and subsequently a filter device 25 and a dryer device 26 are provided, in which the produced hydrogen gets filtered and dried. The filter device 25 and the dryer device 26 can alternatively also be located in the second subsystem 30.

[0069] From the dryer device 26, the produced hydrogen produced flows via the bidirectional line sections 40a and 40c to a further check valve device 35, which marks an end of line section 40c. From there, via line sections 40h and 40i, the produced hydrogen flows into the second energy sink device 32 functioning as a medium-pressure storage device, which is connected to a further line section 40j via a valve device 33, which in particular is provided as a shut-off valve, for example in the form of a solenoid valve. In line section 40j, which ends in the second energy source device 31, which is formed as a high-pressure storage device, upstream of the second energy source device 31 a compressor device 34, in particular in the form of a piston compressor, is provided. The generated hydrogen is stored in the second energy source device 31 by actuating the compressor device 34. Further, this compressor device 34, together with the second energy source device 31, functions as a pressure adaption device 50, which comes to use during the performance of the method according to the invention. The hydrogen intermediately stored in the second energy sink device 34 gets stored into the second energy source device 32 upon actuation of the compressor device 34.

[0070] This production process of the hydrogen up to its storage in the second energy source device 31 represents a first mode of operation of the energy system 10. In this first mode of operation of the energy system 10, bidirectional line sections 40a to 40e of the connecting line device 40 have a pressure of 20 to 60 bar. Such a pressure also prevails in the second energy sink device 32. By means of the compressor device 34, the hydrogen which is withdrawn from the second energy sink device 32, which is an intermediary storage device, is compressed to such an extent that it can be stored at pressures of up to 700 bar in the second energy source device 31, which is a high-pressure storage device.

[0071] The hydrogen stored in the second energy source device 31 is used for the operation of the first energy sink device 22 in the form of the fuel cell device. The operation of the fuel cell device takes place in the second mode of operation of the energy system 10. However, the fuel cell device can only operate at pressures of less than 20 bar. In the second mode of operation of the energy system 10, the hydrogen is removed from the second energy source device 22 via a line section 40, gets expanded via an expansion device 36 in the form of a pressure reducer and gets transported via a bidirectional 40a, from where it enters the first energy sink device 22 designed as a fuel cell device via bidirectional line section 40b. The reduction of the pressure in bidirectional line sections 40a to 40e of the connecting line device 40 to a value of less than 20 bar is achieved by means of pressure adaption device 50. To measure the pressure, at least one pressure measuring device 41, for example in the form of a pressure sensor, is provided.

[0072] The energy system 10 illustrated in FIGS. 1 to 4 represents a partial area of an overall house energy system, which is a multi-hybrid house energy storage system that is electrically autonomous and that is completely based on renewable energies.

[0073] The multi-hybrid house energy storage system makes it possible that the electrical energy generated by a photovoltaic (PV) system, a small wind power plant or the like is distributed as required to the entire year. The system acts as an island system independent of the electrical network. Rather, the system is to ensure the electrical autarchy of the house, so that no electrical energy has to be drawn from the power grid over the entire year.

[0074] The primary task of the house power system is to make available the recovered electrical energy from photovoltaic (PV) modules or the like to the consumer in the household. Secondary, electrical energy excesses can be temporarily stored in a battery short-term storage device at times of low load or high irradiation. Tertiary, the electrical energy can be medium to long-term stored in the hydrogen long-term storage as gaseous hydrogen for times of low irradiation such as night, winter or the like, and can be needs-based made available again at any time by means of a fuel cell.

[0075] Besides to energy-related tasks, the system also functions as a controlled living room ventilation by means of a built-in ventilation device.

[0076] The hydrogen produced in the electrolysis device flows via the hydrogen line into the outwardly provided pressure storage system.

[0077] In the event of a lack of or insufficient PV energy, energy is supplied from the battery to cover the consumer load. If the energy stored in the short-term storage device is not sufficient, the fuel cell device can satisfy the additional electrical energy requirement. In the fuel cell operation, the hydrogen flows from the pressure storage system to the fuel cell device via the hydrogen line.

[0078] The simultaneous operation of the fuel line device and the electrolysis device is excluded. The entire system is operated centrally via an energy manager with predictive energy management.

[0079] In principle, the second subsystem is provided for operation in the outer region, but can also be erected and operated within a special region of the house under certain conditions.

[0080] The procedure of the method according to the invention is now explained with reference to FIGS. 2 to 4.

[0081] In FIG. 2, a first mode of operation of the energy system 10 is illustrated. When the hydrogen is generated in the first energy source device 21, which is an electrolysis device, the line sections marked in bold of the connecting line device 40 as well as the second energy sink device 32 in the form of the medium-pressure storage device have a pressure level of 20 to 60 bar. However, the pressure reducer in the first energy sink device 22 in the form of the fuel cell device can regulate pressures up to less than 20 bar only. Therefore, no fuel cell operation is possible at this line pressure.

[0082] FIG. 3 depicts the transition from the first mode of operation of the energy system 10 to its second mode of operation. By closing the valve device 33, as a result of which the path into the second energy sink device 32 is terminated. By closing the valve device 33, the second energy sink device is decoupled from the connecting line device 40 at this time of the method, so that the hydrogen with the pressure of 20 to 60 bar prevailing in the second energy sink device 31 can remain therein at this pressure. Due to a compression by means of the compressor device 34 in the second energy source device 31 in the form of the high-pressure storage device, the pressure of the reduced volume gets reduced in those line sections of the connecting line device 40, which are marked in bold and in dashed lines. The pressure reduction is accelerated by the reduced volume. When the fuel cell operating pressure of less than 20 bar is reached in the line sections of the connecting line device 40 marked in bold and dashed lines, the pressure reduction is completed.

[0083] Finally, FIG. 4 shows the second mode of operation of the energy system 10. By opening the valve device 33 and switching off the compressor device 34, the initial state is restored. The pressure of the second energy sink device 32 in the form of the medium-pressure storage device is now on up to the check valve device 35 and the compressor device 34, which is illustrated by the bold-marked line sections of the connecting line device 40. The bidirectional line sections of the connecting line device 40 continue to have the reduced fuel cell operating pressure of less than 20 bar up to the first energy sink device 22 in the form of the fuel cell device, which is illustrated by the bold and dashed marked line sections of the connecting line device 40. The fuel cell device can now get started.

LIST OF REFERENCE NUMERALS

[0084] 10 Energy system (house energy system) [0085] 20 First subsystem (inner system) [0086] 21 First energy source device (electrolysis device) [0087] 22 First energy sink device (fuel cell device) [0088] 23 Purging device (purge chamber) [0089] 24 Check valve device [0090] 25 Filter device [0091] 26 Dryer device [0092] 30 Second subsystem (outer system) [0093] 31 Second energy source device (high-pressure storage device) [0094] 32 Second energy sink device (medium-pressure storage device) [0095] 33 Valve device [0096] 34 Compressor device [0097] 35 Check valve device [0098] 36 Expansion device (pressure reducer) [0099] 40 Connecting line device [0100] 40a to 40e Bidirectional line section [0101] 40f to 40k Line section [0102] 41 Pressure measuring device [0103] 50 Pressure adaption device