CN214012988U

CN214012988U - Proton conduction SOEC and oxygen ion conduction SOFC combined device

Info

Publication number: CN214012988U
Application number: CN202120100109.8U
Authority: CN
Inventors: 王建强; 严慧娟; 洪春峰; 马成国; 郭育菁; 杜贤龙; 肖国萍
Original assignee: Shanghai Institute of Applied Physics of CAS
Current assignee: Shanghai Institute of Applied Physics of CAS
Priority date: 2021-01-14
Filing date: 2021-01-14
Publication date: 2021-08-20
Anticipated expiration: 2031-01-14

Abstract

The utility model relates to a proton conduction SOEC and oxygen ion conduction SOFC integrated unit, the hydrogen manufacturing system is proton conduction type SOEC electrolysis vapor hydrogen manufacturing plant, power supply system provides the electrolysis power to the hydrogen manufacturing system, water supply system provides raw material water to the hydrogen manufacturing system, hydrogen distribution system provides protection hydrogen to the hydrogen manufacturing system, the hydrogen storage that the hydrogen manufacturing system produced stores up hydrogen system to the purification buffering, power generation system is oxygen ion conduction type SOFC power generation facility, hydrogen distribution system provides raw materials hydrogen to power generation system, electric management system consumes the electric energy that hydrogen produced with power generation system and carries electric management system in, the heat of production is stored to the fused salt heat-retaining system in. According to the proton conduction SOEC and oxygen ion conduction SOFC combined device, the hydrogen production device efficiently electrolyzes hydrogen and simultaneously reduces the manufacturing difficulty, the power generation device not only generates electric energy, but also recovers high-quality heat generated by power generation by using molten salt heat storage, and the overall energy utilization efficiency is high.

Description

Proton conduction SOEC and oxygen ion conduction SOFC combined device

Technical Field

The present invention relates to hydrogen for high temperature hydrogen production, and more particularly to a proton conducting SOEC and oxygen ion conducting SOFC combination.

Background

The hydrogen is produced by electrolyzing water and the hydrogen fuel cell is used for generating power, which is considered as one of effective modes that renewable energy sources can be fully utilized and the power grid can be stabilized by peak clipping and valley leveling. However, how to improve the energy utilization rate is a major problem in the hydrogen production by electrolyzing water and generating electricity by using a hydrogen fuel cell.

The existing water electrolysis hydrogen production technology can be divided into high-temperature water electrolysis hydrogen production and low-temperature water electrolysis hydrogen production. The low-temperature water electrolysis hydrogen production comprises alkaline water electrolysis hydrogen production, PEM water electrolysis hydrogen production and the like, the direct current conversion rate of the low-temperature water electrolysis hydrogen production is generally between 40 and 55 percent, and the working temperature is generally maintained at 60 to 90 ℃. The high-temperature water electrolysis hydrogen production refers to oxygen ion conduction type SOEC, the direct current conversion efficiency of the SOEC can reach more than 90 percent, and the working temperature is 600-1000 ℃.

The existing hydrogen fuel cell can also be divided into high temperature and low temperature, the low temperature fuel cell takes PEMFC as a representative, and the working temperature is 60-80 ℃; the high-temperature fuel cell mainly refers to SOFC, and the maximum working temperature can reach 1000 ℃. In actual work, the highest energy utilization rate of the low-temperature fuel cell is not more than 70 percent; if heat recovery is carried out, the energy utilization rate of the high-temperature fuel cell can reach more than 95%.

As described above, in terms of energy conversion, hydrogen is produced by high-temperature electrolysis and power is generated optimally. However, the working temperature of the existing high-temperature water electrolysis hydrogen production is too high, and hydrogen needs to be continuously introduced in the electrolysis process to ensure that the hydrogen electrode is not inactivated and the stability is kept, so that the problems of high manufacturing difficulty, high manufacturing cost and the like are caused.

SUMMERY OF THE UTILITY MODEL

In order to solve the big scheduling problem of the manufacturing degree of difficulty among the above-mentioned prior art, the utility model provides a proton conduction SOEC and oxygen ion conduction SOFC integrated unit.

According to the utility model discloses a proton conduction SOEC and oxygen ion conduction SOFC integrated unit, it includes the power supply system, water supply system, hydrogen manufacturing system, purification buffer memory hydrogen storage system, hydrogen distribution system, power generation system, electricity management system and fused salt heat storage system, wherein, hydrogen manufacturing system is proton conduction type SOEC electrolysis vapor hydrogen manufacturing plant, power supply system and hydrogen manufacturing system are connected in order to provide the electrolytic power supply to hydrogen manufacturing system, water supply system and hydrogen manufacturing system are connected in order to provide raw materials water to hydrogen manufacturing system, hydrogen distribution system and hydrogen manufacturing system are connected in order to provide protection hydrogen to hydrogen manufacturing system, purification buffer memory hydrogen storage system and hydrogen manufacturing system are connected in order to store the hydrogen that hydrogen manufacturing system produced to purification buffer memory hydrogen storage system, power generation system is oxygen ion conduction type SOFC power generation facility, hydrogen distribution system and power generation system are connected in order to provide raw materials hydrogen to power generation system, the electricity management system is connected with the power generation system to transmit electric energy generated by the power generation system consuming hydrogen to the electricity management system, and the molten salt heat storage system is connected with the power generation system to store heat generated by the power generation system consuming hydrogen to the molten salt heat storage system.

Preferably, the hydrogen production system comprises an electrolytic cell, a steam generator, a gas preheater and a gas cooling separation assembly, wherein the electrolytic cell is a proton conduction type solid oxide electrolytic cell for high-temperature electrolysis of steam to produce hydrogen, a water supply system is connected with the steam generator to heat raw material water from the water supply system into steam, the gas preheater is connected between the electrolytic cell and the steam generator, the steam enters the anode side of the electrolytic cell after passing through the gas preheater and is electrolyzed, then loses electrons to generate oxygen, the electrolyzed hydrogen ions pass through an electrolyte layer to reach the cathode side of the electrolytic cell to obtain electrons to generate hydrogen, the hydrogen serving as protective gas enters the cathode side of the electrolytic cell after passing through the gas preheater, and the gas cooling separation assembly is connected to the downstream of the electrolytic cell to separate the oxygen out and convey the hydrogen into a purification and cache system.

Preferably, the operating temperature of the cell is maintained between 400 ℃ and 700 ℃.

Preferably, the power generation system comprises a fuel cell, an air purifier, an air supercharger, a gas preheater and a hydrogen internal circulation device, wherein the fuel cell is an oxygen ion conduction type solid oxide fuel cell for high-temperature power generation, the air purifier is connected with the fuel cell through an air supercharger and a gas preheater in sequence, the air is processed by the air purifier, the hydrogen enters a gas preheating machine through an air supercharger and then enters the cathode side of a fuel cell, the hydrogen enters the anode side of the fuel cell after passing through the gas preheating machine, a hydrogen internal circulation device is connected between the fuel cell and the gas preheating machine, unreacted hydrogen reenters the anode side of the fuel cell together with the hydrogen from the gas preheating machine through the hydrogen internal circulation device for cyclic utilization, the fuel cell is connected with an electric management system to output generated electric power, and the fuel cell is connected with a molten salt heat storage system to output generated heat.

Preferably, the operating temperature of the fuel cell is maintained between 700 ℃ and 1000 ℃.

Preferably, the proton conducting SOEC and oxygen ion conducting SOFC combination further comprises an electrical control system, wherein the electrical control system provides the entire proton conducting SOEC and oxygen ion conducting SOFC combination with an active power source and control strategy.

Preferably, the power supply system comprises high-voltage alternating current, a power distributor, surplus power, a step-down transformer, an AC-DC alternating current-direct current and constant voltage/constant current regulating module, wherein the high-voltage alternating current is supplied to the electric equipment for normal use through the power distributor, and the surplus power is connected with the hydrogen production system sequentially through the step-down transformer, the AC-DC alternating current-direct current and the constant voltage/constant current regulating module.

Preferably, the proton conducting SOEC and oxygen ion conducting SOFC combination further comprises an external hydrogen supply system, wherein the external hydrogen supply system inputs hydrogen to the purification cache hydrogen storage system.

Preferably, the proton conducting SOEC and oxygen ion conducting SOFC combination further comprises a hydrogen using system, wherein the hydrogen gas distribution system provides hydrogen gas to the hydrogen using system.

Preferably, the electricity management system comprises a power distributor, a DC-DC converter, a DC-AC DC-to-AC converter and a step-up transformer, wherein the power distributor is respectively connected with the power generation system, the DC-DC converter and the DC-AC DC-to-AC converter to respectively transmit power from the power generation system to the DC-DC converter and the DC-AC DC-to-AC converter through the power distributor, the DC-DC converter is directly used by the DC power equipment, and the DC-AC DC-to-AC converter is fed back to the power grid through the step-up transformer.

According to the utility model discloses a proton conduction SOEC and oxygen ion conduction SOFC integrated unit, wherein proton conduction type SOEC electrolysis vapor hydrogen plant is when guaranteeing high-efficient electrolysis hydrogen manufacturing, can reduce the manufacturing degree of difficulty of hydrogen manufacturing system, manufacturing cost has been reduced, also need not continuously let in hydrogen after the steady operation and protect the hydrogen electrode, wherein oxygen ion conduction type SOFC power generation facility has both produced the electric energy and has retrieved the high-quality heat that the electricity generation produced with the fused salt heat-retaining, make the hydrogen energy obtain make full use of, holistic energy utilization efficiency is high.

Drawings

Fig. 1 is a schematic diagram of the overall structure of a proton conducting SOEC and oxygen ion conducting SOFC combination according to a preferred embodiment of the present invention;

fig. 2 is a detailed structural schematic diagram of the power supply system of fig. 1;

FIG. 3 is a schematic diagram of a specific configuration of the hydrogen production system of FIG. 1;

FIG. 4 is a schematic diagram of a specific configuration of the power generation system of FIG. 1;

fig. 5 is a schematic diagram of a specific structure of the electrical management system of fig. 1.

Detailed Description

The following description of the preferred embodiments of the present invention will be made with reference to the accompanying drawings.

As shown in fig. 1, the combined device of proton conduction SOEC and oxygen ion conduction SOFC according to a preferred embodiment of the present invention includes an electrical control system 1, an electric power supply system 2, a water supply system 3, a hydrogen production system 4, an external hydrogen supply system 5, a purification cache hydrogen storage system 6, a hydrogen distribution system 7, a hydrogen utilization system 8, a power generation system 9, an electrical management system 10, and a molten salt heat storage system 11, wherein the electrical control system 1 provides an action power supply and a control strategy for

other systems

2, 3, 4, 5, 6, 7, 8, 9, 10, 11; the external hydrogen supply system 5 inputs hydrogen into the purification cache hydrogen storage system 6; the hydrogen gas distribution system 7 supplies hydrogen gas to the hydrogen using system 8; the hydrogen production system 4 is a high-temperature proton conduction type SOEC (steam electrolytic hydrogen production) device, the power supply system 2 provides a direct-current electrolytic power supply for the hydrogen production system 4, the water supply system 3 provides raw material water for the hydrogen production system 4, the hydrogen distribution system 7 provides protective hydrogen for the hydrogen production system 4, and the hydrogen produced by the hydrogen production system 4 is stored in the purification cache hydrogen storage system 6; the power generation system 9 is a high-temperature oxygen ion conduction SOFC power generation device, the hydrogen distribution system 7 provides raw material hydrogen for the power generation system 9, electric energy generated by the power generation system 9 through hydrogen consumption is transmitted to the electricity management system 10, and generated heat enters the molten salt heat storage system 11.

According to the utility model discloses a proton conduction SOEC and oxygen ion conduction SOFC integrated unit combine together high temperature proton conduction type SOEC electrolysis vapor hydrogen manufacturing installation and high temperature oxygen ion conduction type SOFC power generation facility for the temperature that hydrogen manufacturing system 4 needs reduces, thereby reduces hydrogen manufacturing system 4's the manufacturing degree of difficulty, power generation system 9 can retrieve the heat source that reaches the high-quality that is close 1000 ℃ when guaranteeing directly to use electric power simultaneously, the energy that hydrogen contains has been utilized to the at utmost.

As shown in fig. 1, the electrical control system 1 is connected to electrical devices in

other systems

2, 3, 4, 5, 6, 7, 8, 9, 10, 11, including a strong electricity room and a weak electricity room, and has functions of supplying power to the electrical devices, monitoring system operation conditions, adjusting operating parameters, and collecting, recording, and storing data.

As shown in fig. 1 and 2, the power supply system 2 is connected to the electrical control system 1 and the hydrogen production system 4, respectively, high-voltage ac power 21 from the power grid is supplied to the consumers through the power distributor 22 for normal use, and surplus power 23 is distributed to the hydrogen production system 4 to convert the electric energy into hydrogen gas for storage. Specifically, the surplus power 23 is connected to the hydrogen production system 4 sequentially through the step-down transformer 24, the AC-DC converter 25 and the constant voltage/constant current regulation module 26, and provides a stable electrolysis power supply for the hydrogen production system 4.

As shown in fig. 1, the water supply system 3 is connected to the electrical control system 1 and the hydrogen production system 4 through pipes, respectively. Specifically, water supply system 3 includes water purification device, storage water tank and water delivery pump, and former feed water flows into the storage water tank behind water purification device, has liquid level detection device in the storage water tank, and through automatic water supply device automatic water supply when the water level in the storage water tank is low excessively, has water delivery pump behind the storage water tank, carries former feed water for hydrogen manufacturing system 4.

As shown in fig. 1 and fig. 3, the hydrogen production system 4 is respectively connected to the electrical control system 1, the power supply system 2, the water supply system 3 and the purification, cache and hydrogen storage system 6, and is further connected to the hydrogen distribution system 7 to obtain a small amount of hydrogen to make shielding gas at startup. The core of the hydrogen production system 4 is to produce hydrogen by electrolyzing water vapor at high temperature through a proton conduction type Solid Oxide Electrolytic Cell (SOEC)41, the working temperature is maintained between 400 ℃ and 700 ℃, specifically, a high-temperature proton conduction type electrolyte is adopted, the materials are mostly BCZY and BZCYb electrolytes, when the temperature is in the range of 400 ℃ to 700 ℃, the high-temperature proton conduction type electrolyte has better proton conduction capability and is used for electrolyzing water vapor at high temperature to produce hydrogen, the water vapor enters the anode side of the electrolytic cell 41, and the hydrogen is produced at the cathode side of the electrolytic cell 41. The hydrogen production system 4 further comprises a water vapor generator 42, a gas preheater 43 and a gas cooling and separating assembly 44, the water supply system 3 is connected with the water vapor generator 42 to heat the raw material water from the water supply system 3 into water vapor, the gas preheater 43 is used for preheating the hydrogen and water vapor used as the shielding gas entering the electrolytic cell 41, specifically, the water vapor enters the anode side of the electrolytic cell 41 after passing through the gas preheater 43, the hydrogen used as the shielding gas enters the cathode side of the electrolytic cell 41 after passing through the gas preheater 43, after the electric power supply system provides direct current, the water vapor enters the anode side of the electrolytic cell 41 to be electrolyzed, then electrons are lost to generate oxygen, the electrolyzed hydrogen ions pass through the electrolyte layer to reach the cathode side of the electrolytic cell to obtain electrons to generate hydrogen, the hydrogen is closed after stabilization, the gas cooling and separating assembly 44 is connected at the downstream of the electrolytic cell 41 to separate the oxygen and convey the hydrogen into the purification cache hydrogen storage system 6.

As shown in fig. 1, the external hydrogen supply system 5 is connected to the electrical control system 1 and the purification and cache hydrogen storage system 6, respectively, and provides additional hydrogen gas independently from the hydrogen production system 4, and the hydrogen supply mode can be long-tube trailer, pipeline transportation, etc.

As shown in fig. 1, the front end of the purification cache hydrogen storage system 6 is connected to the hydrogen production system 4 and the external hydrogen supply system 5, and the rear end is connected to the hydrogen distribution system 7, and the purification system includes a purification part and a hydrogen storage part, wherein the purification part is mainly used for removing impurity gases from the hydrogen production system 4 and the external hydrogen supply system 5 and then storing the hydrogen, and can select the modes of temperature swing adsorption purification, pressure swing adsorption purification, membrane separation purification and the like, and the hydrogen storage part can be used for storing hydrogen in metal, high pressure, and liquid states in consideration of the problems of energy density, use occasion and the like in combination with the actual situation.

As shown in fig. 1, the front end of the hydrogen distribution system 7 is connected to the purification cache hydrogen storage system 6, and the rear end is connected to the hydrogen utilization system 8 and the power generation system 9, so as to deliver the hydrogen in the purification cache hydrogen storage system 6 to the hydrogen utilization system 8 and the power generation system 9 according to the variation of the hydrogen utilization requirement. The hydrogen distribution system 7 comprises a valve group consisting of a pressure reducing valve, a one-way valve, a four-way valve, a pneumatic ball valve and the like, and monitoring equipment consisting of a pressure sensor, a flowmeter and the like.

As shown in fig. 1 and 4, the power generation system 9 is connected to the electrical control system 1, the hydrogen gas distribution system 7, the electrical management system 10, and the molten salt heat storage system 11, respectively. The core of the power generation system 9 is high-temperature power generation through an oxygen ion conduction type Solid Oxide Fuel Cell (SOFC)91, the working temperature is 700-1000 ℃, a cooling system is not needed to maintain the working temperature, and the heat generated by the reaction has high recycling value. The power generation system 9 further comprises an air purifier 92, an air supercharger 93, a gas preheater 94 and a hydrogen internal circulation device 95, wherein air is processed by the air purifier 92, enters the gas preheater 94 through the air supercharger 93 and then enters the cathode side of the fuel cell 91, hydrogen passes through the gas preheater 94 and enters the anode side of the fuel cell 91, unreacted hydrogen and hydrogen from the gas preheater 94 enter the anode side of the fuel cell 91 again through the hydrogen internal circulation device 95 for recycling, the fuel cell 91 is connected with the electric management system 10 to output generated electric power, and the fuel cell 91 is connected with the molten salt heat storage system 11 to output generated heat.

As shown in fig. 1 and 5, the electrical management system 10 is connected to the electrical control system 1 and the power generation system 9 respectively, and includes a power distributor 101, a DC-DC converter 102, a DC-AC direct-to-alternating current 103 and a step-up transformer 104, wherein the power from the power generation system 9 is transmitted to the DC-DC converter 102 and the DC-AC direct-to-alternating current 103 respectively through the power distributor 101, the DC-DC converter 102 is directly used by the direct-current consumers, and the DC-AC direct-to-alternating current 103 is fed back to the grid through the step-up transformer 104.

As shown in fig. 1, the molten salt heat storage system 11 is connected to the electrical control system 1 and the power generation system 9, respectively, and is configured to store and recover heat generated in the power generation system 9, where the recovered heat can be used for gas preheating and temperature rise of the whole apparatus, plant heating, and the like.

What has been described above is only the preferred embodiment of the present invention, not for limiting the scope of the present invention, but various changes can be made to the above-mentioned embodiment of the present invention. All the simple and equivalent changes and modifications made according to the claims and the content of the specification of the present invention fall within the scope of the claims of the present invention. The present invention is not described in detail in the conventional technical content.

Claims

1. The proton conduction SOFC and oxygen ion conduction SOFC combined device is characterized by comprising a power supply system (2), a water supply system (3), a hydrogen production system (4), a purification cache hydrogen storage system (6), a hydrogen distribution system (7), a power generation system (9), an electricity management system (10) and a molten salt heat storage system (11), wherein the hydrogen production system (4) is a proton conduction type SOEC water vapor electrolysis hydrogen production device, the power supply system (2) is connected with the hydrogen production system (4) to provide an electrolysis power supply for the hydrogen production system (4), the water supply system (3) is connected with the hydrogen production system (4) to provide raw material water for the hydrogen production system (4), the hydrogen distribution system (7) is connected with the hydrogen production system (4) to provide protective hydrogen for the hydrogen production system (4), and the purification cache hydrogen storage system (6) is connected with the hydrogen production system (4) to store the hydrogen generated by the hydrogen production system (4) to pure hydrogen In the chemical cache hydrogen storage system (6), the power generation system (9) is an oxygen ion conduction type SOFC power generation device, the hydrogen distribution system (7) is connected with the power generation system (9) to provide raw material hydrogen for the power generation system (9), the electric management system (10) is connected with the power generation system (9) to transmit electric energy generated by the power generation system (9) consuming hydrogen to the electric management system (10), and the molten salt heat storage system (11) is connected with the power generation system (9) to store heat generated by the power generation system (9) consuming hydrogen into the molten salt heat storage system (11).

2. The SOFC combination of proton conducting SOEC and oxygen ion conducting SOFC device according to claim 1, wherein the hydrogen production system (4) comprises an electrolytic cell (41), a steam generator (42), a gas preheater (43) and a gas cooling separation assembly (44), wherein the electrolytic cell (41) is a proton conducting solid oxide electrolytic cell for high temperature electrolysis of steam to produce hydrogen, the water supply system (3) is connected to the steam generator (42) to heat the raw water from the water supply system (3) into steam, the gas preheater (43) is connected between the electrolytic cell (41) and the steam generator (42), the steam passes through the gas preheater (43) and enters the anode side of the electrolytic cell (41) to be electrolyzed and then loses electrons to produce oxygen, and the electrolyzed hydrogen ions pass through the electrolyte layer to reach the cathode side of the electrolytic cell (41) to obtain electrons to produce hydrogen, hydrogen gas used as shielding gas passes through a gas preheater (43) and enters the cathode side of the electrolytic cell (41), and a gas cooling separation assembly (44) is connected downstream of the electrolytic cell (41) to separate out oxygen and deliver the hydrogen gas into a purification cache hydrogen storage system (6).

3. A proton conducting SOEC and oxygen ion conducting SOFC combination according to claim 2, characterised by the operating temperature of the electrolytic cell (41) being maintained between 400 ℃ and 700 ℃.

4. The SOFC combination of proton conducting SOEC and oxygen ion conducting SOFC according to claim 1, wherein the power generation system (9) comprises a fuel cell (91), an air cleaner (92), an air supercharger (93), a gas preheater (94), and a hydrogen gas internal circulation device (95), wherein the fuel cell (91) is an oxygen ion conducting solid oxide fuel cell for high temperature power generation, the air cleaner (92) is connected to the fuel cell (91) through the air supercharger (93) and the gas preheater (94) in this order, the air is processed by the air cleaner (92), then enters the gas preheater (94) through the air supercharger (93), then enters the cathode side of the fuel cell (91), the hydrogen gas enters the anode side of the fuel cell (91) through the gas preheater (94), the hydrogen gas internal circulation device (95) is connected between the fuel cell (91) and the gas preheater (94), unreacted hydrogen enters the anode side of the fuel cell (91) again for recycling through a hydrogen internal circulation device (95) together with hydrogen from a gas preheating machine (94), the fuel cell (91) is connected with an electric management system (10) to output generated electric power, and the fuel cell (91) is connected with a molten salt heat storage system (11) to output generated heat.

5. Combined proton conducting SOEC and oxygen ion conducting SOFC according to claim 4, characterized in that the operating temperature of the fuel cell (91) is maintained between 700 ℃ and 1000 ℃.

6. The combination proton conducting SOEC and oxygen ion conducting SOFC according to claim 1, characterized by further comprising an electrical control system (1), wherein the electrical control system (1) provides the entire combination proton conducting SOEC and oxygen ion conducting SOFC with power for action and control strategy.

7. Combined proton conducting SOEC and oxygen ion conducting SOFC device according to claim 1, characterized in that the power supply system (2) comprises a high voltage alternating current (21), a power distributor (22), an excess power (23), a step-down transformer (24), an AC-DC alternating current to direct current (25) and a constant voltage/constant current regulation module (26), wherein the high voltage alternating current (21) is supplied to the consumers for normal use through the power distributor (22), and the excess power (23) is connected to the hydrogen production system (4) through the step-down transformer (24), the AC-DC alternating current to direct current (25) and the constant voltage/constant current regulation module (26) in this order.

8. The proton conducting SOEC and oxygen ion conducting SOFC combination according to claim 1, further comprising an external hydrogen supply system (5), wherein the external hydrogen supply system (5) inputs hydrogen to the purification cache hydrogen storage system (6).

9. The proton conducting SOEC and oxygen ion conducting SOFC combination according to claim 1, further comprising a hydrogen using system (8), wherein the hydrogen gas distribution system (7) provides hydrogen gas to the hydrogen using system (8).

10. A proton conducting SOEC and oxygen ion conducting SOFC combination according to claim 1, characterized by the electrical management system (10) comprising a power distributor (101), a DC-DC converter (102), a DC-AC DC-to-AC converter (103) and a step-up transformer (104), the power distributor (101) being connected to the power generation system (9), the DC-DC converter (102) and the DC-AC DC-to-AC converter (103) respectively for delivering power from the power generation system (9) to the DC-DC converter (102) and the DC-AC DC-to-AC converter (103) respectively through the power distributor (101), the DC-DC converter (102) being directly available for DC consumers, the DC-AC DC-to-AC converter (103) being fed back to the grid through the step-up transformer (104).