CN209200758U - A distributed photovoltaic power generation hydrogen energy storage system - Google Patents

Abstract

The utility model discloses a kind of distributed photovoltaic power generation hydrogen energy-storage systems, including solar panel, solar panel is mutually electrically connected with inverter and hydrogen energy-storage units respectively by master controller, a part that solar panel conversion gets electric energy is inputted into inverter for domestic loads normal electricity consumption by master controller, extra electric energy after the higher metal hydride energy-storage units storage of adsorptivity by being powered.The utility model passes through using hydrogen as hydrogen energy-storage units, in the daytime the extra electric energy issued is passed through electrolytic tank electrolysis water manufacture hydrogen and hydrogen is temporarily stored in the hydrogen storage material of high adsorption, hydrogen storage material discharges hydrogen and is passed through hydrogen fuel cell power generation when night electricity consumption, realization, which converts electrical energy into chemical energy and is then converted to electric energy, to be efficiently used, clean and environmental protection, capacity usage ratio are high, are easy to build.

Description

A distributed photovoltaic power generation hydrogen energy storage system

technical field

The utility model belongs to the field of photovoltaic power generation and relates to hydrogen energy storage technology, in particular to a distributed photovoltaic power generation hydrogen energy storage system in the form of efficient and safe metal hydride hydrogen storage.

Background technique

Due to its self-sufficiency and no need to consider grid connection, distributed photovoltaic power generation has been widely used in household power supply in remote areas. Combined, it has the ability to migrate energy over time, so that the excess power generated during the day can be used at night. At present, the main energy storage method for distributed photovoltaic power generation is electrochemical energy storage, among which lead-acid batteries, sodium-sulfur batteries, lithium batteries, etc. are mainly used, but this energy storage method often has high cost and short life , and the components are difficult to recycle and easily pollute the environment. The electrochemical energy storage technology still needs to be developed and perfected.

Utility model content

In order to solve the problems of high component cost, short service life and difficult recycling in traditional electrochemical energy storage, the utility model provides a hydrogen energy storage system for distributed photovoltaic power generation.

The technical scheme adopted by the utility model is as follows: a distributed photovoltaic power generation hydrogen energy storage system, including a solar panel, the solar panel is electrically connected to the inverter and the hydrogen energy storage unit through the general controller, and the A part of the incoming electrical energy converted by the solar panels is input into the inverter for the normal consumption of household loads, and the excess electrical energy is stored by the highly adsorbed metal hydride energy storage unit for power supply.

Further, the output end of the hydrogen energy storage unit is connected to the input end of the inverter.

Further, the hydrogen energy storage unit includes an alkaline electrolytic cell and a PEM hydrogen fuel cell. The positive and negative electrodes of the alkaline electrolytic cell are electrically connected to the general controller, and the excess electric energy generated during the day is input into the alkaline electrolytic cell through the control of the general controller. Hydrogen is produced by electrolyzing water in the middle, and the PEM hydrogen fuel cell receives hydrogen power generation and inputs it into the inverter.

Further, the hydrogen energy storage unit also includes a hydrogen storage device, the alkaline electrolytic cell is connected to the hydrogen storage device, the hydrogen storage device is connected to the PEM hydrogen fuel cell, and the cathode and anode of the PEM hydrogen fuel cell are connected to the inverter. electric connection.

Preferably, the alkaline electrolytic cell uses iron, nickel and their alloys as electrodes, and the electrolyte is KOH aqueous solution with a concentration of 25% to 30%.

Preferably, the hydrogen storage device is equipped with metal hydrides for freely absorbing, storing and releasing hydrogen.

Preferably, a proton exchange membrane is provided between the cathode and the anode of each unit cell in the PEM hydrogen fuel cell.

Preferably, the hydrogen storage device and the PEM hydrogen fuel cell are connected through an _H2 output pipe, and a control valve controlled by the master controller is arranged in the pipe.

Preferably, the solar panels are placed on top of the facility or building.

A hydrogen energy storage method using the above-mentioned distributed photovoltaic power generation hydrogen energy storage system, specifically comprising the following steps:

Step (1). The solar panel is placed on the top of the facility or building to realize photovoltaic power generation. The solar panel converts a part of the electrical energy converted by the solar panel into the inverter through the master controller and converts it into AC power for normal use of household loads. ;

Step (2). The excess electric energy generated by the solar panels during the day is input into the alkaline electrolytic cell to electrolyze water to prepare hydrogen, and input the hydrogen storage device;

Step (3). The hydrogen storage device and the PEM hydrogen fuel cell are connected through the H ₂ output tube, and the PEM hydrogen fuel cell receives hydrogen power generation input inverter for normal power consumption of household loads.

The beneficial effects of the present utility model are:

1. The utility model uses the general controller to input part of the electric energy converted by the solar panel into the inverter for normal use of household appliances, and the other part of the excess electric energy generated during the day is stored by the hydrogen energy storage unit for power supply. . When the power generated by the solar panel is not enough to supply the household load, the stored electric energy is used to realize electric energy compensation.

2. The utility model uses hydrogen as the hydrogen energy storage unit, passes the excess electric energy generated during the day into the electrolyzer to electrolyze water to produce hydrogen, and temporarily stores the hydrogen in a hydrogen storage material with high adsorption, and stores it at night when electricity is used The hydrogen material releases hydrogen and passes it into the hydrogen fuel cell to generate electricity, realizing the cycle process of converting electrical energy into chemical energy and then into electrical energy.

3. The hydrogen storage device of the present utility model can absorb, store and release hydrogen relatively freely through its internal metal hydride. Compared with other hydrogen storage methods, the metal hydride hydrogen storage has the advantages of stable pressure, simple hydrogen filling, With the advantages of safety and convenience, the density per unit volume of hydrogen storage can reach 1000 times that of gaseous hydrogen under the same temperature and pressure conditions, and the energy storage density exceeds that of liquid hydrogen storage under ideal conditions. The metal hydrides of the utility model are selected from the hydrides of lanthanide metals, alkali metals and some alkaline earth metals (LaNi ₅ H ₆ , MgH ₂ , NaAlH ₄ , etc.). High and long life, hydrogen storage reaction is reversible, low energy consumption, high purity hydrogen and high safety factor, clean and environmentally friendly, high energy utilization rate, easy to build.

Description of drawings

Fig. 1. process flow chart of the present utility model;

Fig. 2. structural representation of the utility model;

Fig. 3 is a schematic diagram of the principle of metal hydride hydrogen storage of the utility model.

In the figure: 1. Solar panel, 2. Master controller, 3. Household load, 4. Alkaline electrolytic cell, 5. Hydrogen storage device, 6. PEM hydrogen fuel cell, 7. Inverter, 8. Oxygen collection Device, 9. Combiner box.

Detailed ways

Below in conjunction with specific accompanying drawing, the utility model is described in further detail;

As shown in Figures 1 and 2, a hydrogen energy storage system for distributed photovoltaic power generation includes solar panels, which are placed on top of facilities or buildings to realize the function of photovoltaic power generation. The solar panel 1 is electrically connected to the inverter and the hydrogen energy storage unit respectively through the general controller 2, and through the general controller 2, a part of the electrical energy converted by the solar panel is input into the inverter 7 and converted into AC power for the household load 3 For normal electricity consumption, excess electricity is stored by the hydrogen energy storage unit for power supply.

The hydrogen energy storage unit includes an alkaline electrolytic cell 4, a (metal) hydrogen storage device 5, and a PEM hydrogen fuel cell 6. The positive and negative electrodes of the alkaline electrolytic cell are electrically connected to the general controller, and the solar energy is controlled by the general controller. The excess electric energy generated by the battery board during the day is input into the alkaline electrolytic cell to electrolyze water to realize the production of hydrogen. The alkaline electrolytic cell is connected to the hydrogen storage device, and the hydrogen storage device and the PEM hydrogen fuel cell are connected through the _H2 output tube connected, the tube is provided with a control valve controlled by the master controller, the cathode and anode of the PEM hydrogen fuel cell are electrically connected to the inverter, and the hydrogen power is received by the PEM hydrogen fuel cell and input to the inverter.

The hydrogen energy storage method using the above-mentioned distributed photovoltaic power generation hydrogen energy storage system specifically includes the following steps:

Step (1). The solar panel is placed on the top of the facility or building to realize photovoltaic power generation. The solar panel converts a part of the electrical energy converted by the solar panel into the inverter through the master controller and converts it into AC power for normal use of household loads. ;

Step (2). The excess electric energy generated by the solar panels during the day is input into the alkaline electrolytic cell to electrolyze water to prepare hydrogen, and input the hydrogen storage device;

Step (3). The hydrogen storage device and the PEM hydrogen fuel cell are connected through the H ₂ output tube, and the PEM hydrogen fuel cell receives hydrogen power generation input inverter for normal power consumption of household loads.

The above-mentioned alkaline electrolysis often uses durable materials such as iron, nickel and their alloys as electrodes, and the electrolyte is a KOH aqueous solution with a concentration of 25% to 30%. Under the standard state, the potential difference of water splitting is 1.23V, and the power consumption is 2.95KWh/m ³ , while the actual power consumption in alkaline environment is 4.5-5.5KWh/m ³ , and the efficiency is 53.6%-62%. This hydrogen production method has low cost, mature technology, wide application range and simple structure.

The hydrogen storage device is equipped with a metal hydride inside, which can absorb, store and release hydrogen relatively freely. Using this method, the hydrogen storage density can reach more than 1,000 times that of hydrogen under standard conditions. Under ideal conditions, the energy storage density exceeds liquid hydrogen storage. The choice of metal hydrides can be LaNi ₅ H ₆ , MgH ₂ , NaAlH ₄ , etc. The hydrogen storage reaction is reversible, the energy consumed is low, and the obtained hydrogen gas has high purity and high safety factor. The principle of metal hydride hydrogen storage is shown in Figure 3.

PEM hydrogen fuel cell, its single cell is composed of anode, cathode and proton exchange membrane, the proton exchange membrane is located between the cathode and anode, both electrodes contain catalysts to increase the reaction rate of the electrode, and the proton exchange membrane is used as the medium for transferring H ⁺ , only allowing H ⁺ passes through, while the electrons lost by _H2 pass through the wire. Its working temperature is about 100°C. It is equivalent to a DC power supply when working, and can continuously generate electric energy. Its work is controlled by the master controller. When the external light intensity is relatively high When the temperature is low, the power generated by the solar panel is not enough to supply the load. At this time, the hydrogen fuel cell automatically works to realize the compensation of electric energy.

The electrical energy flowing out of the master controller and the electrical energy compensated by the PEM fuel cell flow through the combiner box to be combined, and finally flow into the inverter and output to be used by household loads.

Selection of electrolysis voltage:

In an alkaline electrolytic cell, the reaction to electrolyze water is as follows:

2H ₂ O==2H ₂ +O ₂ ΔH=571.6KJ

Hydrogen production half reaction: 2H ₂ O+2e ^- ==H ₂ +2OH ^-

Therefore, for every 1 mole of hydrogen produced, 2 moles of electrons are required to be transferred, and the charge is:

q=2×6.02×10 ²³ ×1.6×10 ^-19 C=1.9264×10 ⁵ C

1molH2 has a chemical energy of 285.8KJ, so the optimum voltage for the reaction is:

U=W/q=(285.8×10 ³ )/(1.9264×10 ⁵ )V=1.48V

Therefore, the total controller should control the electrolysis voltage to be around 1.5V.

Claims (9)

1. A hydrogen energy storage system for distributed photovoltaic power generation, characterized in that: it includes a solar panel, the solar panel is electrically connected to the inverter and the hydrogen energy storage unit through the general controller, and the solar battery is connected to the solar battery through the general controller. Part of the electrical energy converted by the board is input into the inverter for normal use of household loads, and the excess electrical energy is stored by the hydrogen energy storage unit for power supply. 2. A hydrogen energy storage system for distributed photovoltaic power generation according to claim 1, characterized in that the output end of the hydrogen energy storage unit is connected to the input end of the inverter. 3. A distributed photovoltaic power generation hydrogen energy storage system according to claim 1 or 2, characterized in that: the hydrogen energy storage unit includes an alkaline electrolytic cell and a PEM hydrogen fuel cell, and the positive and negative electrodes of the alkaline electrolytic cell are connected to The main controller is electrically connected, through the main controller, the excess electric energy generated during the day is input into the alkaline electrolytic cell to electrolyze water to produce hydrogen, and the PEM hydrogen fuel cell is used to receive hydrogen to generate electricity and input it to the inverter. 4. A distributed photovoltaic power generation hydrogen energy storage system according to claim 3, characterized in that: the hydrogen energy storage unit also includes a hydrogen storage device, the alkaline electrolytic cell is connected to the hydrogen storage device, and the hydrogen storage device is connected to the hydrogen storage device The PEM hydrogen fuel cells are connected, and the cathode and anode of the PEM hydrogen fuel cells are connected with the inverter. 5. A hydrogen energy storage system for distributed photovoltaic power generation according to claim 4, characterized in that: the alkaline electrolytic cell uses iron, nickel and their alloys as electrodes, and the electrolyte is KOH aqueous solution with a concentration of 25% to 30% . 6. A distributed photovoltaic power generation hydrogen energy storage system according to claim 4 or 5, characterized in that the hydrogen storage device is equipped with metal hydrides for freely absorbing, storing and releasing hydrogen. 7. A hydrogen energy storage system for distributed photovoltaic power generation according to claim 6, characterized in that a proton exchange membrane is provided between the cathode and anode of each single cell in the PEM hydrogen fuel cell. 8. A distributed photovoltaic power generation hydrogen energy storage system according to claim 4, 5 or 7, characterized in that: the hydrogen storage device and the PEM hydrogen fuel cell are connected through the _H2 output pipe, and the pipe There is a control valve controlled by the master controller. 9. A distributed photovoltaic power generation hydrogen energy storage system according to claim 8, characterized in that: solar panels are placed on top of facilities or buildings.