Electrification device and electrification method

Abstract

To provide an easy-to-use electrification device using soil, the present invention provides an electrification device comprising: a conducting part, which is provided in the vicinity of a foundation or support of a generating device that generates renewable energy, and in which an electrically conductive material is mixed into ion-containing soil; a positive electrode provided to the conducting part; a negative electrode provided to the conducting part; and a separator provided to the conducting part so as to isolate the positive and negative electrodes from each other, wherein the electrically conductive material and the positive electrode are connected, the electrically conductive material and the negative electrode are connected, and when a voltage from the generating device is applied between the positive and negative electrodes, anions are led to the positive electrode and cations are led to the negative electrode.

Description

Charging device and charging method

[0001] The present invention relates to a charging device and a charging method that can store electricity using soil.

[0002] In recent years, power generation devices using renewable energy have been selling the generated electricity to electric power companies by reverse flowing it back into the power grid. However, in order to maintain a balance between power supply and demand in the power grid, output control, which controls the power output to the power grid, is sometimes required, even for solar power plants, for example. In Japan, it has been reported that the total power output will reach approximately 1.9 billion kW-h in 2023, and the current situation is that renewable energy is not being effectively utilized. On the other hand, when output control is required, it has been proposed to store renewable energy in a storage battery (see, for example, Patent Document 1). Furthermore, in recent years, it has been proposed to blend electrically conductive nanoporous carbon into cement, form a nanoporous carbon network using the fluidity of water, and use the concrete as a capacitor (see, for example, Patent Document 2).

[0003] International Patent Publication No. 2020 / 162461 U.S. Patent No. 1,1512,022

[0004] However, Patent Document 1 only proposes storing renewable energy in a storage battery when output control is required, and does not disclose any issues such as high initial costs or how to handle maintenance. Furthermore, Patent Document 2 only proposes storing electricity in concrete to create a capacitor, and does not propose other applications or safety measures for actual use.

[0005] Therefore, an object of the present invention is to provide an easy-to-use charging device and charging method using soil.

[0006] The charging device described in claim 1 comprises a separator provided between a positive electrode and a negative electrode, and a conductive portion in which an electrically conductive material having carbon black and activated carbon is mixed into soil containing ions, wherein the weight ratio of the activated carbon to the soil is greater than the weight ratio of the carbon black to the soil, the electrically conductive material is connected to the positive electrode, and the electrically conductive material is connected to the negative electrode, and when a voltage is applied between the positive electrode and the negative electrode, anions are guided to the positive electrode and cations are guided to the negative electrode. The charging device described in claim 5 is provided near the foundation or frame of a generating device that generates renewable energy, and includes a conductive part in which an electrically conductive material is mixed into soil containing ions, a positive electrode provided in the conductive part, a negative electrode provided in the conductive part, and a separator provided in the conductive part so as to insulate the positive electrode from the negative electrode, wherein the electrically conductive material is connected to the positive electrode and the electrically conductive material is connected to the negative electrode, and when a voltage from the generating device is applied between the positive electrode and the negative electrode, anions are guided to the positive electrode and cations are guided to the negative electrode. The charging method described in claim 12 includes providing a conductive section in which an electrically conductive material is mixed into soil containing ions near the foundation or base of a generating device that generates renewable energy, providing a positive electrode, a negative electrode, and a separator in the conductive section, connecting the electrically conductive material to the positive electrode and the electrically conductive material to the negative electrode, and when a voltage from the generating device is applied between the positive electrode and the negative electrode, introducing anions to the positive electrode and introducing cations to the negative electrode.

[0007] According to the charging device of claim 1, the weight ratio of activated carbon to soil is greater than the weight ratio of carbon black to soil, so that a charging device with a simple configuration and low cost can be realized. According to the charging device of claim 5, electricity can be stored in the vicinity of the generator using the voltage from the generator. According to the charging method of claim 12, electricity can be stored in the vicinity of the generator using the voltage from the generator.

[0008] 4(a) is a schematic diagram showing a state in which a capacitor is provided near a solar power generation system, with FIG. 4(a) being a schematic diagram showing a state in which a capacitor is buried in the ground, and FIG. 4(b) being a schematic diagram showing a state in which a capacitor is provided near a foundation. FIG. 4(b) is an enlarged cross-sectional view of the capacitor in FIG. 4. FIG. 4(c) is a block diagram of a control device for controlling the charging and discharging of the capacitor in the first embodiment. FIG. 6 is an application example of the block diagram in FIG. 6. FIG. 6(d) is a flowchart executed by the control unit in the first embodiment. FIG. 9(a) is a schematic diagram showing a state in which a capacitor is provided near a wind power generation system, with FIG. 9(a) being a schematic diagram showing a state in which a capacitor is buried in the ground, and FIG. 9(b) being a schematic diagram showing a state in which a capacitor is provided near a foundation.

[0009] First Embodiment A first embodiment will be described in detail below with reference to FIGS. 1 to 8. In this first embodiment, an electrically conductive material is mixed into soil to form conductive soil, and this conductive soil is used to provide a capacitor 11, which will be described later. In this first embodiment, the electrically conductive material is a material that has electronic conductivity, which allows electrons to move, and ionic conductivity, which allows ions to move. In this first embodiment, a combination of carbon black and binchotan charcoal is used as the electronically conductive material, and soil 2 containing moisture is used as the ionic conductive material, but this is not limited to this.

[0010] (Preliminary experiment to confirm the insulating properties of soil) Figure 1 is a cross-sectional view showing soil 2 placed in a glass container 1 with two copper plates 3 inserted into the soil 2. The soil 2 was collected in Tsukuba City, Ibaraki Prefecture, and was placed in the container 1 after being sieved through a 4.75 mm mesh sieve. Note that the container 1 may be made of resin instead of glass, and any material may be used as long as it has insulating properties. Furthermore, even if the container 1 is made of a material that does not have insulating properties, it may be made insulating by coating or spraying, for example, an alkylalkoxysilane-based insulating agent or a silanesiloxane-based insulating agent.

[0011] When soil 2 was subjected to a soil quality test, the density of the soil particles was found to be 2.660 g / cm ３ The natural water content was 35.7%. The particle size of Soil 2 was 4.5% gravel, 39.5% sand, 42.0% silt, and 14.0% clay. As a result, Soil 2 was classified as sandy silt.

[0012] Sandy silt contains calcium ions (Ca ２＋ ) and magnesium ions (Mg ２＋ ), soil 2 can be used as an electrolyte. If the electrolyte substance in soil 2 is insufficient, calcium ions (Ca ２＋ ), potassium ions (K ＋ ), magnesium ions (Mg ２＋ ), sodium ions (Na ＋ ) or other cations with a high ionization tendency can be added to the soil 2 as an electrolyte substance.

[0013] For example, cement contains calcium ions (Ca ２＋ ) and may be mixed with soil 2 as soil cement.

[0014] When the test leads of the tester were brought into contact with each of the two copper plates 3, no continuity was confirmed, resulting in a non-conductive state. As a result, no continuity was confirmed in the soil 2.

[0015] (Mixing of Soil and Electrically Conductive Material) The aforementioned soil 2 was mixed with an electrically conductive material. The electrically conductive material used was a combination of carbon black and binchotan charcoal, but this is not limited thereto. For example, a single carbon-derived material (e.g., binchotan charcoal or activated carbon) may also be used as the electrically conductive material. Carbon black forms a carbon network and, when mixed with soil 2, is an ideal material for lowering the internal resistance of soil 2 and increasing the charge capacity of soil 2. Binchotan charcoal is an ideal material for absorbing and releasing ions. In this first embodiment, acetylene black, produced by the thermal decomposition of acetylene, was used as the carbon black. However, Ketjenblack, a registered trademark, whose primary particles have a hollow shell structure, may also be used, as may inexpensively available activated carbon. In this case, activated carbon primarily consisting of micropores or mesopores is preferred.

[0016] The carbon-derived binchotan may be crushed or commercially available powdered binchotan. Alternatively, sawdust charcoal (sawdust binchotan), which is made from sawdust compressed under high pressure, may be used. Instead of binchotan, activated carbon with macropores may be used.

[0017] Although acetylene black and binchotan charcoal are hydrophobic substances, they become somewhat compatible with water when soaked in water for about a day. In this case, it is preferable to stir them for about 10 to 30 minutes immediately after soaking them in water. In this first embodiment, acetylene black and binchotan charcoal are soaked in water and then mixed with soil 2. This improves the compatibility between soil 2, acetylene black, and binchotan charcoal.

[0018] The amount of acetylene black added is 5% to less than 20% by weight of soil 2. If the amount of acetylene black added is 5% or more by weight of soil 2, a carbon network can be formed within soil 2. If the amount of acetylene black added is 20% or more by weight of soil 2, the resistance value of mixture 4, which will be described later, will be further reduced, but in this first embodiment, the amount is set to less than 20% in consideration of the price and cost-effectiveness of acetylene black.

[0019] The amount of binchotan charcoal added is 8% or more and less than 25% by weight of soil 2. If the amount of binchotan charcoal added is 8% or more by weight of soil 2, charging using ions of soil 2 by capacitor 11, which will be described later, becomes possible. The amount of binchotan charcoal added may be 25% or more by weight of soil 2, but in this first embodiment, it is less than 25% in consideration of the price and cost-effectiveness of binchotan charcoal. Furthermore, when activated carbon is used instead of binchotan charcoal, the amount of activated carbon added may be 8% or more and less than 25% by weight of soil 2.

[0020] The amount of binchotan charcoal added varies depending on the properties of the soil 2, the amount of electrolyte contained in the soil 2, and whether or not an electrolyte is added, so the above amount should be used as a guideline. Furthermore, considering the performance of the capacitor 11 (charge amount, charging time, etc.) described below, it is preferable that the amount of binchotan charcoal added be greater than the amount of acetylene black added. The amount of acetylene black added may also be determined taking into account the internal resistance (several ohms to tens of ohms) when mixed with the soil 2. Even when activated carbon is used instead of binchotan charcoal, it is preferable that the amount of activated carbon added be greater than the amount of acetylene black added. Furthermore, when both binchotan charcoal and activated carbon are used, it is preferable that the combined amount of binchotan charcoal and activated carbon added be greater than the amount of acetylene black added.

[0021] In the first embodiment, the soil 2, acetylene black, and crushed binchotan charcoal were mixed for several minutes (1 to 2 minutes) in a mixer, which is a mixing machine, to prepare the mixture 4.

[0022] (Experiment to Confirm the Conductivity of the Mixture) FIG. 2 is a cross-sectional view showing a state in which a mixture 4 is placed in a container 1 and two copper plates 3 are inserted into the mixture 4. As shown in FIG.

[0023] When the test leads of a tester were brought into contact with each of the two copper plates 3, the resistance value was about 20 to 30 Ω, confirming the conductivity of the mixture 4. This confirmed that an electrically conductive network had been formed in the soil 2 by carbon black, a carbon-derived material.

[0024] The reason why the resistance value fluctuates by about 10 Ω is because the contact state of the electrically conductive material becomes unstable due to the inclusion of gas (air) in the mixture 4. For this reason, the mixture 4 was manually compacted using a metal tamping rod, and the resistance value of the mixture 4 was measured again.

[0025] After manual compaction, the resistance of Mixture 4 was about 18-20 Ω, and it was confirmed that the resistance decreased and the fluctuations in the resistance also decreased. Note that this resistance can be reduced to a few Ω by increasing the amount of carbon black added to 10-15%.

[0026] In this first embodiment, the mixture 4 is a conductive portion in which an electrically conductive carbon network is formed, and this conductive portion is used to realize a capacitor 11 as a charging device that utilizes the ions of the soil 2.

[0027] (Experiment to confirm power storage using mixture) Fig. 3 shows the state of capacitor 11 during charging, and is illustrated as a cross-sectional view excluding power source 8. As shown in Fig. 3, after a separator 5 is attached to container 1, mixture 4 is placed therein, and then a positive electrode 6 and a negative electrode 7 are inserted into mixture 4 to form capacitor 11 of the first embodiment.

[0028] The separator 5 prevents direct contact between the positive electrode 6 and the negative electrode 7 and short-circuits, while allowing ions in the mixture 4 to pass through the formed carbon network. In the first embodiment, the separator 5 can be made of a polyolefin resin such as polyethylene or polypropylene, or a polyester resin such as polyethylene terephthalate or polybutylene terephthalate. The separator 5 can also be made of a cellulose-derived nonwoven fabric or paper (e.g., Japanese paper or kitchen paper). The separator 5 may also be made of a composite material of a cellulose-derived nonwoven fabric or paper with polyethylene or glass fiber. The separator 5 is fixed to the container 1 with insulating tape. Alternatively, the separator 5 may be sandwiched between insulating materials and placed in the container 1. It is preferable to use a hydrophilic material for the separator 5 to facilitate the passage of ions. The separator 5 can be fixed by forming a recess in the bottom of the container 1 and using this recess, by using insulating tape, or by other methods.

[0029] The positive electrode 6 can be made of a material that does not easily react chemically with the ionic substances contained in the soil 2, such as copper, aluminum, platinum, or a carbon material. In this first embodiment, a copper plate 3 is used. The positive electrode 6 is connected to a carbon network formed from acetylene black. An electric double layer is formed near the surface of the binchotan charcoal connected to this carbon network, and the positive electrode 6 is charged by attracting anions with the opposite charge.

[0030] The negative electrode 7 can be made of a material that is unlikely to react chemically with the ionic substances contained in the soil 2, such as copper, aluminum, platinum, or a carbon material. In this first embodiment, a copper plate 3 is used. The negative electrode 7 is connected to a carbon network formed from acetylene black. An electric double layer is formed near the surface of the binchotan charcoal connected to this carbon network, and the negative electrode 7 is charged by attracting cations with opposite charges. Note that sheet-like carbon fiber may also be used as the carbon material for the positive electrode 6 and the negative electrode 7. Carbon fiber is lightweight and strong, making it an easy-to-use electrode.

[0031] The power supply 8 is used to charge the capacitor 11, and may be a constant voltage power supply, a constant current power supply, etc. The capacitor 11 may be charged by either constant voltage charging or constant current charging, but in the first embodiment, constant current charging is used from the viewpoint of charging efficiency.

[0032] One end of the wire 9 is connected to the positive electrode 6, and the other end is connected to the + output terminal of the power supply 8. One end of the wire 10 is connected to the negative electrode 7, and the other end is connected to the − output terminal of the power supply 8.

[0033] In the first embodiment, a constant voltage power supply was used as the power supply 8, and charging was performed at a voltage of 1 V to 3 V. When the water content of the mixture 4 was high, charging was performed at 1.2 V or less to prevent hydrogen generation, and when the water content of the mixture 4 was low, i.e., when little hydrogen was generated, charging was performed at 3 V.

[0034] After charging for several minutes or 5 to 10 minutes (depending on the state of the mixture 4), when wires 9 and 10 were connected to a rotary motor (not shown), the rotary motor rotated. This confirmed that a carbon network was formed in the soil 2 using acetylene black, and that ions were being absorbed and released by the binchotan charcoal, an ion-absorbing material. In other words, it was confirmed that electricity could be stored using the mixture 4.

[0035] In addition, a mixture 4 was newly prepared in the above weight ratio, and sodium ions (Na＋ ) was added. Specifically, several hundred cc of 5% concentration saline solution was added. Then, as in the case of the above, it was charged at a voltage of 1.2 V for the same time (several minutes or about 5 to 10 minutes). After that, when the wires 9 and 10 were connected to the rotary motor, the rotary motor generated sodium ions (Na ＋ Mixture 4 rotated longer than Mixture 4 without the addition of .

[0036] In this way, the addition of cations increases the charge of capacitor 11, allowing it to supply more power. Therefore, the amount of binchotan charcoal or activated carbon that absorbs and releases ions may be determined based on the amount of ions in mixture 4. The applicant of the present application also discovered that the electricity storage performance of capacitor 11 deteriorates when mixture 4 dries. Therefore, it is preferable to store mixture 4 in an environment where humidity is easily maintained, or to supply a liquid such as water to mixture 4 when it dries. This can prevent deterioration of the electricity storage performance of capacitor 11 or restore a capacitor 11 whose electricity storage performance has deteriorated.

[0037] Furthermore, in civil engineering and construction, soil has played a role as the ground and foundation, but according to the first embodiment, in addition to these roles, soil also plays a role in storing electricity, making it possible to realize an electric double layer capacitor using soil. When the capacitor 11 shown in Fig. 3 is used outdoors, a waterproof sheet may be provided above the capacitor 11 or a lid may be placed on the capacitor 11 to prevent rain, snow, etc. from penetrating the capacitor 11. As the waterproof sheet, a polyvinyl chloride sheet, a high-density polyethylene sheet, or the like may be used.

[0038] (Installation of Capacitor Near a Photovoltaic Power Generation Device) Hereinafter, the case where the above-described capacitor 11 is installed near a photovoltaic power generation device 30 that generates renewable energy will be described.

[0039] 4A and 4B are schematic diagrams showing a capacitor 11 provided near a solar power generation device 30, with FIG. 4A being a schematic diagram showing a capacitor 11 buried in the ground 36 and FIG. 4B being a schematic diagram showing a capacitor 11 installed near a foundation 35. In FIG. 4B, the capacitors 11 are arranged in a stacked manner with support members 37 interposed therebetween. As is clear from FIG. 4A, the capacitors 11 are not arranged directly below the foundations 35 in order to prevent the foundations 35 from sinking. As is clear from FIG. 4B, the capacitors 11 are arranged between two foundations 35. The number of capacitors 11 can be set arbitrarily.

[0040] The solar power generation device 30 includes a solar cell panel 31, a mounting base 34 having a panel support portion 32 and a support pillar 33, and a concrete foundation 35. A plurality of foundations 35 are installed on the ground 36. The mounting bases 34 are placed on the foundations 35. The solar cell panel 31 is supported by the mounting bases 34. The mounting base 34 may have any shape as long as it can support the solar cell panel 31, and the number of support pillars 33 may be one.

[0041] In the first embodiment, the concrete foundation 35 may be buried in the ground 36, or the foundation 35 may be omitted and the posts 33 may be driven into the ground 36. If the capacitor 11 is provided below the solar power generation device 30, the solar power generation device 30 acts as an umbrella, and the capacitor 11 can be prevented from being exposed to rain, snow, or sunlight.

[0042] Figure 5 is an enlarged cross-sectional view of the capacitor 11 in Figure 4. The capacitor 11 in Figure 4 is used outdoors, and therefore a cover member and maintenance members are added to the capacitor 11 in Figure 3. Note that in Figures 4 and 5, the wiring 9, wiring 10, and piping 42 are partially omitted to avoid complicating the drawings. Also, in Figures 4 and 5, the vertical direction is illustrated as the Z direction, and the direction perpendicular to the left-right direction of the Z direction is illustrated as the X direction. Note that, although not shown, the direction perpendicular to the paper surface is the Y direction.

[0043] The first lid member 40 is a lid that covers the container 1, and in the first embodiment, a circular resin member is used. For example, if the first lid member 40 is a circular resin member, a female thread may be formed on the inner surface of the container 1 and a male thread may be formed on the outer surface of the first lid member 40, and the first lid member 40 may cover the container 1 by screwing the male thread and the female thread together. Alternatively, the first lid member 40 may be shaped to cover the container 1 from above, and the container 1 and the first lid member 40 may be fastened together by fastening members such as bolts. When fastening members such as bolts are used, the container 1 and the first lid member 40 may be shaped in any desired manner, such as rectangular.

[0044] The first cover member 40 has a communication hole 41 that communicates with the outside. In the first embodiment, three communication holes 41 a, 41 b, and 41 c are formed so as to face the separator 5, the positive electrode 6, and the negative electrode 7, respectively, but the present invention is not limited to this.

[0045] The communication hole 41 a is a hole for performing maintenance on the separator 5, and in the first embodiment, a pipe 42 passes through the communication hole 41 a to supply water (e.g., distilled water such as pure water) to the separator 5. In the first embodiment, water is supplied to the separator 5 because ions become less likely to move when the separator 5 dries.

[0046] The communication hole 41b is a hole for passing a first pipe member 43 through which the wiring 9 from the positive electrode 6 is passed. The communication hole 41c is a hole for passing a second pipe member 44 through which the wiring 10 from the negative electrode 7 is passed. PF (Plastic Flexible) pipes can be used as the first pipe member 43 and the second pipe member 44. The lengths of the first pipe member 43 and the second pipe member 44 can be set as desired.

[0047] The second cover member 45 is a cover member provided in correspondence with the communication hole portion 41. The second cover member 45a covers the communication hole portion 41a and has an opening through which a pipe 42 passes that supplies water (e.g., distilled water such as pure water) to the separator 5. If it is necessary to prevent rain from seeping in through this opening, sealing tape may be wrapped around the opening, or a clay material or the like may be provided.

[0048] The second cover member 45b covers the communication hole portion 41b and has an opening through which the first pipe member 43 passes to pass the wire 9 from the positive electrode 6. If it is necessary to prevent rain from seeping in through this opening, sealing tape may be wrapped around the opening or a clay material or the like may be provided.

[0049] The second cover member 45c covers the communication hole portion 41c and has an opening through which the second pipe member 44 passes for passing the wiring 10 from the negative electrode 7. If it is necessary to prevent rain from seeping in through this opening, sealing tape may be wrapped around the opening or a clay material or the like may be provided.

[0050] In the first embodiment, a female thread is provided in the communication hole portion 41, and a male thread that screws into the female thread is provided in the second lid member 45, thereby engaging the second lid member 45 with the communication hole portion 41. When it is necessary to replace at least one of the separator 5, the positive electrode 6, and the negative electrode 7, this can be done with the first lid member 40 removed. At this time, the mixture 4 may be replaced, or an electrolyte material may be supplied to the mixture 4.

[0051] Furthermore, by providing opposing recesses in the bottom (lower surface) of the container 1 and the top of the first lid member 40 and fitting the support member 37 into these recesses, it is possible to arrange a plurality of capacitors 11 along the Z direction. The dimension of the support member 37 in the height direction (Z direction) may be set taking into consideration the connection and maintenance of the piping 42.

[0052] The electrolyte substance is preferably supplied in the form of a solution, for example, by dissolving it in water. This makes it possible to prevent deterioration of the electricity storage performance of capacitor 11 and to recover capacitor 11 whose electricity storage performance has deteriorated. When first lid member 40 is engaged with container 1, the electrolyte substance may be supplied to mixture 4 using communication holes 41a, 41b, and 41c.

[0053] As shown in Figure 4(a), by burying capacitors 11 in the ground 36, it is possible to utilize previously unused space in the ground 36. Furthermore, by digging up the ground 36 and installing capacitors 11 in layers via support members 37, or by arranging capacitors 11 in the direction perpendicular to the plane of the page, it is possible to install more capacitors 11 in the ground. Furthermore, by using soil dug up from the ground 36 to make the mixture 4, it is possible to save on the cost of transporting soil.

[0054] 4(b), by providing capacitors 11 near foundation 35 or support pillar 33, it is possible to utilize the space below solar cell panel 31 that has not been used up until now. Furthermore, by stacking capacitors 11 via support members 37 or by arranging capacitors 11 in the direction perpendicular to the plane of the page, it is possible to install more capacitors 11 below solar cell panel 31. Furthermore, in the first embodiment, multiple capacitors 11 may be provided both underground and above ground.

[0055] 6 is a block diagram of a control device 50 for controlling the charging and discharging of the capacitor 11 in the first embodiment. In the first embodiment, the charging of the capacitor 11 is performed by the solar power generation device 30 described above, but the present invention is not limited to this.

[0056] The control device 50 has a power generation side switching unit 51, a power generation power conditioner 52, a voltage conversion unit 53, a charging switch 54, a discharging power conditioner 55, a discharge side switching unit 56, a memory 57, a communication unit 58, and a control unit 59.

[0057] The power generation side switching unit 51 is connected to the solar power generation device 30 and the control unit 59, and is a switching unit that switches whether the power generated by the solar power generation device 30 is to be reversely flowed to the power grid via the power generation power conditioner 52, or whether the power is to be charged to the capacitor 11. Note that the power generation side switching unit 51 may be configured to be able to supply the power generated by the solar power generation device 30 to both the power grid and the capacitor 11.

[0058] The power generation power conditioner 52 has an inverter that converts the direct current output from the solar power generation device 30 into alternating current. The power generation power conditioner 52 also has a function of adjusting the output voltage to allow reverse power flow to the power grid, and a function of disconnecting from the power grid in the event of an abnormality such as an earthquake. The power generation power conditioner 52 allows the power generated by the solar power generation device 30 to flow back into the power grid, but may also supply power to each element that makes up the control device 50.

[0059] The voltage converter 53 converts the voltage of the direct current output from the solar power generation device 30 into a voltage (for example, 1 V to 1.2 V) suitable for charging the capacitor 11 , and outputs the voltage to the charging switch 54 .

[0060] Charging switch 54 is an on / off switch, and when the switch is on, solar power generation device 30 charges capacitor 11, and when the switch is off, solar power generation device 30 does not charge capacitor 11. Charging switch 54 is turned off under the control of control unit 59 when it is necessary to prevent capacitor 11 from being overcharged.

[0061] The discharge power conditioner 55 has an inverter that converts the direct current output from the capacitor 11 into alternating current. The discharge power conditioner 55 also has a function of adjusting the output voltage to allow reverse power flow to the power grid and to supply power to the load device 60, and a function of disconnecting from the power grid in the event of an abnormality such as an earthquake. The function of disconnecting from the power grid in the event of an abnormality may be performed by the discharge-side switching unit 56.

[0062] The discharge-side switching unit 56 is a switching unit that can be connected to the power grid and the load device 60, and switches between allowing the power generated by the capacitor 11 to flow backward to the power grid or supplying it to the load device 60. Note that the discharge-side switching unit 56 may be configured to be able to supply the power generated by the capacitor 11 to both the power grid and the load device 60.

[0063] The memory 57 is a non-volatile memory (for example, a flash memory) and stores a program for controlling the charging and discharging of the capacitor 11, a program for controlling the solar power generation device 30, and the like. The memory 57 also stores the daily charge amount and discharge amount of the capacitor 11 in addition to the daily power generation amount of the solar power generation device 30. The memory 57 may also store the hourly charge amount and discharge amount.

[0064] The communication unit 58 is a wireless communication unit that accesses a wide area network such as the Internet. The communication unit 58 may also use wired communication. In the first embodiment, the communication unit 58 communicates with a remote host computer.

[0065] The communication unit 58 communicates, for example, the daily charge and discharge amounts of the capacitor 11 to the host computer. The host computer may issue an instruction to perform maintenance on the capacitor 11 when there is a decrease in the charge amount or when there is a change in the environment as detected by the environmental sensor 61 (see FIG. 7 ). In this case, the host computer may determine whether to perform maintenance based on parameters such as weather conditions (e.g., sunny or rainy), seasonal conditions (e.g., summer or winter), the time elapsed since the capacitor 11 was installed, and the time elapsed since the last maintenance. Note that maintenance includes at least one of supplying water to the separator 5 constituting the capacitor 11 and supplying water or an electrolyte substance to the mixture 4.

[0066] The control unit 59 includes a CPU and controls the solar power generation device 30 as well as the charging and discharging of the capacitor 11. In the first embodiment, the control unit 59 monitors the voltage of the capacitor 11, and when the voltage becomes lower than a lower threshold, the control unit 59 controls the discharge-side switching unit 56 to prevent discharging. Furthermore, when the voltage becomes higher than an upper threshold, the control unit 59 may control the charging switch 54 to be turned off so that charging of the capacitor 11 is not performed.

[0067] Fig. 7 is an application example of the block diagram of Fig. 6. In the block diagram of Fig. 7, an environmental sensor 61 and a pump 62 are illustrated as loads. The environmental sensor 61 is a thermometer or a hygrometer, and can be driven by a DC power source. For this reason, in the first embodiment, it is connected to the capacitor 11. It is preferable to provide a voltage conversion unit and an on / off switch between the capacitor 11 and the environmental sensor 61.

[0068] When an electrical conductivity sensor that measures the electrical conductivity of the mixture 4 is used as the environment sensor 61, the electrical conductivity sensor is AC driven and therefore may be connected to the discharge power conditioner 55 via the discharge side switching unit 56. The environment sensor 61 may be provided inside the first lid member 40 or may be provided in the mixture 4.

[0069] The pump 62 is connected to the discharge power conditioner 55 via the discharge-side switching unit 56 and supplies water (e.g., distilled water such as pure water) from the pipe 42 to the separator 5. By supplying water to the separator 5, the water is also transferred to the mixture 4, which can prevent the mixture 4 from drying out. In order to supply water to the mixture 4, a spray nozzle may be provided on the pipe 42, or multiple pipes 42 may be provided. The pump 62 may also be used as a pump for supplying an electrolyte material to the mixture 4.

[0070] The control unit 59 supplies water to the separator 5 using the pump 62 when the mixture 4 or the separator 5 is dry, in response to the output of the environmental sensor 61. In this way, if the control unit 59 performs maintenance on the capacitor 11 in response to the output of the environmental sensor 61, the maintenance of the capacitor 11 can be automated. Note that the control of the automated maintenance may be performed by a host computer. Furthermore, the supply of the electrolyte material to the mixture 4 described above may also be automatically controlled by the control unit 59 or the host computer.

[0071] The control by the control unit 59 of the capacitor 11 and the solar power generation device 30 of the first embodiment configured as described above will be described below. Fig. 8 is a flowchart executed by the control unit 59 of the first embodiment. This flowchart is executed when the solar power generation device 30 is capable of generating power and the capacitor 11 is not being charged.

[0072] (Flowchart) The control unit 59 determines whether or not it is possible to charge the capacitor 11 (step S1). When maintenance of the capacitor 11 is not required and the voltage of the capacitor 11 indicates that the capacitor 11 is not in an overcharged state, the control unit 59 determines Yes in step S1 and proceeds to step S2. If the capacitor 11 is overcharged, the control unit 59 repeats the determination in step S1 until the overcharge of the capacitor 11 is resolved. Note that the control unit 59 may end this flowchart if the overcharge of the capacitor 11 is not resolved within a predetermined time (for example, several tens of minutes to several hours).

[0073] Furthermore, when the output of the environmental sensor 61 indicates that maintenance of the capacitor 11 is necessary, the control unit 59 may proceed to step S2 after supplying water from the pipe 42 to the mixture 4 and the separator 5 using the pump 62. Here, it is assumed that charging of the capacitor 11 is possible, and the process proceeds to step S2.

[0074] The control unit 59 switches the switch of the power generation side switching unit 51 to the charging side of the capacitor 11, and also switches the charging switch 54 on to start charging the capacitor 11 (step S2).

[0075] As described above, capacitor 11 may be charged by either constant voltage charging or constant current charging, but constant current charging is preferable in consideration of charging efficiency. When constant current charging is performed, a current control circuit for supplying a constant current between voltage conversion unit 53 and capacitor 11 may be added. In either case of constant voltage charging or constant current charging, charging is performed by applying a voltage from solar power generation device 30.

[0076] The control unit 59 determines whether charging of the capacitor 11 is complete (step S3). When charging of the capacitor 11 is complete, the voltage of the capacitor 11 becomes maximum, while the current flowing through the capacitor 11 becomes minimum (almost zero). Therefore, the control unit 59 can determine whether charging of the capacitor 11 is complete by detecting the voltage of the capacitor 11 or the current flowing through the capacitor 11.

[0077] The control unit 59 continues charging until the charging of the capacitor 11 is completed, and proceeds to step S4 when the charging of the capacitor 11 is completed. Here, it is assumed that the charging of the capacitor 11 is completed, and the process proceeds to step S4. When the charging is completed, the control unit 59 switches the charging switch 54 off. Furthermore, the control unit 59 switches the switch of the power generation side switching unit 51 to the power generation power conditioner 52 side as necessary.

[0078] The control unit 59 determines whether or not power needs to be supplied to the load device 60 (step S4). If power does not need to be supplied to the load device 60, the control unit 59 ends this flowchart, and if power needs to be supplied to the load device 60, the control unit 59 proceeds to step S5. Here, it is assumed that power needs to be supplied to the load device 60, and the control unit 59 proceeds to step S5.

[0079] The control unit 59 causes the capacitor 11 to supply (discharge) power to the load device 60 (step S5). The control unit 59 controls the discharging power conditioner 55 and the discharge-side switching unit 56 to cause the capacitor 11 to supply (discharge) power to the load device 60. The power supply (discharge) to the load device 60 by the capacitor 11 may be performed by constant current discharge, load discharge, or the like. If the load device 60 is an LED, constant current discharge may be performed, and if it is an electronic device, load discharge may be performed.

[0080] The control unit 59 determines whether the power supply (discharge) from the capacitor 11 to the load device 60 can be continued (step S6). The control unit 59 can determine whether the power supply (discharge) to the load device 60 can be continued by monitoring the voltage and current when the capacitor 11 is discharging, or by monitoring the amount of energy consumed relative to the capacitance stored in the capacitor 11.

[0081] In order to avoid interruption of the power supply (discharging) to the load device 60, the control unit 59 sets a threshold value (the above-mentioned voltage value, current value, or amount of consumed energy) for the end of discharging of the capacitor 11, and provides a switching circuit so that when this threshold is exceeded, the power supply (discharging) to the load device 60 is switched to that from another capacitor 11.

[0082] Furthermore, when the power supply (discharge) from capacitor 11 to load device 60 cannot be continued, control unit 59 returns to step S1 and determines whether or not to recharge capacitor 11 that is no longer able to supply (discharge) power. In this case, it is assumed that the power supply can be continued, and the process proceeds to step S7.

[0083] The control unit 59 determines whether or not it is necessary for the capacitor 11 to supply (discharge) power to the load device 60 (step S7). When the environment is detected by the environment sensor 61 or when illumination by an LED is necessary, the control unit 59 determines that it is necessary to supply (discharge) power, and returns to step S5 to continue the power supply.

[0084] On the other hand, if the environment detection by the environment sensor 61 is not required or if it is morning and the LED illumination is no longer required, the control unit 59 determines that power supply (discharge) is not required and ends this flowchart.

[0085] As described above, according to this flowchart, the power generated by the solar power generation device 30 can be charged into the capacitor 11 and can also be supplied to the load device 60. Therefore, even when there is a request to control the output of the solar power generation device 30, the power generated by the solar power generation device 30 can be effectively used.

[0086] Second Embodiment Hereinafter, a second embodiment will be described with reference to Fig. 9. The same components as those in the first embodiment are denoted by the same reference numerals, and their description will be omitted or simplified. In the second embodiment, the capacitor 11 described in the first embodiment is provided near a wind power generation device 70 that generates renewable energy.

[0087] 9A and 9B are schematic diagrams showing a capacitor 11 provided near a wind turbine generator 70, with Fig. 9A being a schematic diagram showing a capacitor 11 buried in the ground 36 and Fig. 9B being a schematic diagram showing a capacitor 11 installed near a base 71. As is clear from Fig. 9A, the capacitor 11 is placed near the base 71, avoiding being directly below the base 71, in order to prevent the base 71 from sinking. As is clear from Fig. 9B, the capacitor 11 is placed on the base 71 in a position that does not interfere with the blades 75 of the wind turbine generator 70.

[0088] The wind power generation device 70 is a power generation facility that converts wind power into electricity, and includes a tower 72, a nacelle 73, a boss 74, and blades 75 on a concrete base 71.

[0089] The tower 72 is made of metal and is a support member that supports the nacelle 73 , the boss 74 , and the wings 75 .

[0090] The nacelle 73 includes a gearbox that increases the rotational speed of the blades 75, a generator that converts energy transmitted from the blades 75 to a rotor (not shown) into electricity, and the like.

[0091] The boss 74 is a support member that rotatably supports the blade 75. The blade 75 is a component that converts wind force into rotational force, and can be made of metal or a carbon fiber composite material.

[0092] In the second embodiment, by replacing the solar power generation device 30 in the block diagrams of Figures 6 and 7 with a wind power generation device 70, the power generated by the wind power generation device 70 can be charged into the capacitor 11 and can also be supplied to the load device 60. Therefore, even if there is a request to control the output of the wind power generation device 70, the power generated by the wind power generation device 70 can be used effectively.

[0093] Solar cell panels 31 may be installed on the roofs of outdoor parking lots at commercial facilities or parking lots at private homes, and capacitors 11 may be installed near such solar cell panels 31. Furthermore, a geothermal power generation device that uses steam generated by geothermal energy may be used as a device for generating renewable energy.

[0094] According to the first and second embodiments described above, even in the event of a power outage due to a natural disaster such as an earthquake, if the device for generating renewable energy is operational, electricity can be stored in capacitor 11, and lighting fixtures, electric fans, heating appliances, etc. can be driven by the electricity stored in capacitor 11. Furthermore, if the electricity stored in capacitor 11 is supplied to a pump that pumps up groundwater, the groundwater can be pumped up and the pumped up groundwater can be used as drinking water.

[0095] Furthermore, when capacitor 11 is buried, container 1 can be made of concrete, and the inner surface of the concrete containing mixture 4 can be made insulating by coating or spraying an insulating agent such as an alkylalkoxysilane or silanesiloxane. This allows the size of concrete container 1 to be set as desired, so that a large capacitor 11 can be realized by increasing the volume of capacitor 11.

[0096] Although U.S. Patent No. 11,512,022 listed in the prior art discloses storing electricity in concrete, it does not disclose how to insulate the reinforcing bars that may be placed in the concrete. In contrast, in the first and second embodiments, the container 1 is made insulating, so that the presence of metal structures around the container 1 does not pose a problem.

[0097] The above-described embodiment is a preferred example of the present invention. However, the present invention is not limited to this, and various modifications are possible within the scope of the gist of the present invention. For example, an electron-conductive conductive polymer may be used as the electron-conductive substance. A conductive polymer may be used as the conductive polymer. In this case, the conductive polymer may be liquefied by dissolving it in a solvent, or by adding an additive to the conductive polymer.

[0098] 2... Soil 3... Copper plate 4... Mixture 5... Separator 6... Positive electrode 7... Negative electrode 11... Capacitor 30... Photovoltaic power generation device 34... Mounting base 35... Foundation 50... Control device 51... Power generation side switching unit 52... Power generation power conditioner 54... Charging switch 55... Discharging power conditioner 56... Discharge side switching unit 59... Control unit 60... Load device 61... Environmental sensor 62... Pump 70... Wind power generation device 71... Foundation

Claims

1. A charging device comprising: a separator provided between a positive electrode and a negative electrode; and a conductive part in which an electrically conductive material having carbon black and activated carbon is mixed into soil containing ions, wherein the weight ratio of the activated carbon to the soil is greater than the weight ratio of the carbon black to the soil, and wherein the electrically conductive material is connected to the positive electrode and the negative electrode, and when a voltage is applied between the positive electrode and the negative electrode, the charging device introduces anions to the positive electrode and introduces cations to the negative electrode.

2. The charging device according to claim 1, further comprising an environmental sensor for measuring the environment of said conductive portion.

3. The charging device according to claim 2, wherein the environmental sensor includes an electrical conductivity sensor for measuring the electrical conductivity of the conductive portion.

4. A charging device according to any one of claims 1 to 3, further comprising a liquid supply device that supplies liquid to at least one of the conductive portion and the separator.

5. A charging device comprising: a conductive part provided near the foundation or frame of a generating device that generates renewable energy, and in which an electrically conductive material is mixed into soil containing ions; a positive electrode provided in the conductive part; a negative electrode provided in the conductive part; and a separator provided in the conductive part so as to insulate the positive electrode from the negative electrode, wherein the electrically conductive material is connected to the positive electrode and the electrically conductive material is connected to the negative electrode, and when a voltage from the generating device is applied between the positive electrode and the negative electrode, the charging device guides anions to the positive electrode and cations to the negative electrode.

6. The charging device according to claim 5, wherein the conductive portion, the positive electrode, the negative electrode, and the separator are buried in the vicinity of the base or the stand.

7. The charging device according to claim 5 or 6, further comprising a container that houses the conductive portion, the positive electrode, the negative electrode, and the separator.

8. The charging device according to claim 7, wherein the container is made of glass or concrete.

9. The charging device according to claim 5, wherein the generating device is connected to a power grid and includes a control device that charges the capacitor using the renewable energy during output control, and the charging device comprises a capacitor including the conductive portion, the positive electrode, the negative electrode, and the separator.

10. The charging device according to claim 9, further comprising a liquid supply device for supplying liquid to at least one of said conductive portion and said separator.

11. The charging device according to claim 10, wherein the liquid supply device supplies the liquid using the power charged in the capacitor.

12. A charging method in which a conductive part in which an electrically conductive material has been mixed into soil containing ions is provided near the foundation or base of a generating device that generates renewable energy, a positive electrode, a negative electrode, and a separator are provided in the conductive part, and the electrically conductive material is connected to the positive electrode and the negative electrode, and when a voltage from the generating device is applied between the positive electrode and the negative electrode, an anion is introduced to the positive electrode and a cation is introduced to the negative electrode.

13. The charging method according to claim 12, wherein the conductive portion, the positive electrode, the negative electrode, and the separator are buried in the vicinity of the base or the stand.

14. The charging method according to claim 12 or 13, wherein the conductive portion, the positive electrode, the negative electrode, and the separator are housed in a container.

15. The charging method according to claim 12, wherein a capacitor is configured with the conductive portion, the positive electrode, the negative electrode, and the separator, and the generating device is connected to a power grid, and the capacitor is charged using the renewable energy during output control.

16. The charging method according to claim 12, wherein a liquid is supplied to at least one of the conductive portion and the separator.

17. The charging method according to claim 16, wherein a capacitor is formed comprising the conductive portion, the positive electrode, the negative electrode, and the separator, and the liquid is supplied by the power charged in the capacitor.

Images