Electrolytic energy recovery

Abstract

The energy supply system includes an electrolysis system that performs electrolysis on a first water source to split water into hydrogen and oxygen components. The hydrogen and oxygen components are supplied to a power generation system. The power generation system includes a combustor that receives the hydrogen and oxygen components and is operable to combust the hydrogen and oxygen components. The combustor also receives a steam source. Combustion products downstream from the combustor pass over the top turbine rotor, driving it to rotate. A first generator generates electrical power from the rotation of the top turbine rotor.

Description

Technical Field

[0001] This application relates to an energy supply system that uses electrolysis to produce hydrogen and oxygen for use during combustion.

Background Art

[0002] Power grids are necessary to supply power to all locations. By way of example, homes, businesses, structures, and buildings are supplied with energy from an energy grid.

[0003] Several types of power plants can supply power to the power grid. By way of example, nuclear energy, solar and wind energy, and fossil fuels are all utilized to generate power supplied to the power grid.

[0004] In some cases, the power supply to the power grid fails or results in insufficient power generation. This is undesirable, and in such cases, it is desirable to develop a reliable backup energy source for supplying power to the power grid.

[0005] In other cases, particularly when power is generated by solar and wind, it is necessary to increase the size of the energy conversion device in consideration of wind fluctuations or times when the sun is not out. However, these overly large systems can convert excess energy beyond what the power grid can utilize and may not be able to be turned off economically. The power grid benefits from having a mechanism for storing this excess energy for times when energy conversion is low.

[0006] In at least one proposed system, water is electrolyzed and decomposed into hydrogen and oxygen components. The separated hydrogen and oxygen are sent to the combustor of an engine where they are mixed and ignited.

[0007] These combustion products pass downstream past the turbine rotor, driving the rotor to rotate. This generates electricity, which can then be separated and recovered by a generator. Downstream of the combustor, the separated hydrogen and oxygen revert to water.

[0008] The separated and recovered water can be sent to a combustor. Alternatively, the separated and recovered water can be returned to the water source for electrolysis.

[0009] While such systems have potential advantages in reducing emissions, the proposed design has drawbacks. [Overview of the project] [Means for solving the problem]

[0010] In a characteristic embodiment, the energy supply system includes an electrolysis system that performs electrolysis on a first water source, splitting water into hydrogen and oxygen components. The hydrogen and oxygen components are supplied to a power generation system. The power generation system includes a combustor that receives the hydrogen and oxygen components and is operable to burn these components. The combustor also receives a steam source. The combustion products downstream of the combustor pass over a top turbine rotor, driving the top turbine rotor to rotate. The first generator generates electricity from the rotation of the top turbine rotor.

[0011] In another embodiment according to the previous embodiment, the evaporator is positioned downstream of the turbine to receive combustion products. A second water supply also passes through the evaporator, and the combustion products cause the water passing through the evaporator to boil. The water that has passed through the evaporator is supplied to the combustor as steam.

[0012] In another embodiment according to one of the preceding embodiments, the condenser is positioned downstream of the evaporator to receive the combustion products. The combustion products are condensed into liquid water by cooling them with a cooling fluid. The liquid water supplied from the condenser is sent to a pressurizing pump. The pressurized water is supplied to the evaporator as a second water source.

[0013] In another embodiment according to one of the preceding embodiments, the working fluid in the condenser is used to preheat the oxygen and hydrogen components that are sent to the combustor.

[0014] In another embodiment according to one of the preceding embodiments, liquid water recovered from the combustion products in the condenser is also sent to the first water source.

[0015] In another embodiment according to one of the preceding embodiments, liquid water recovered from the combustion products in the condenser is also sent to the first water source.

[0016] In another embodiment according to one of the preceding embodiments, steam from a second water source is also selectively injected into the turbine.

[0017] In another embodiment according to one of the preceding embodiments, steam from a second water supply source upstream of the evaporator is also selectively delivered to the intermediate combustion products between the combustor and the turbine.

[0018] In another embodiment according to any of the preceding embodiments, the controller is programmed to control the electrolysis system and the power generation system, to determine the amount of power generated by the other power generation system, to determine the power demand of the power grid, and to perform at least one of the following based on the determination that the amount of power generated exceeds the power demand of the power grid: to operate the electrolysis system and engage / disengage the power generation system, or to stop the operation of the electrolysis system and operate the power generation system based on the determination that the amount of power generated falls below the determined power demand of the power grid.

[0019] In another embodiment according to one of the preceding embodiments, the hydrogen and oxygen components are cooled to a liquid state and stored before being supplied to the combustor.

[0020] In another embodiment according to one of the preceding embodiments, the hydrogen and oxygen components are preheated before being delivered to the combustor.

[0021] In another embodiment according to any of the previous embodiments, the hydrogen and oxygen components are preheated before being delivered to the combustor.

[0022] In another embodiment according to any of the previous embodiments, the combustion products are used to preheat the hydrogen and oxygen components.

[0023] In another embodiment according to any of the previous embodiments, the preheating of the oxygen and hydrogen components is performed in an evaporator.

[0024] [[ID=I2]] In another embodiment according to any of the previous embodiments, a steam turbo expander extracts work from the steam and then delivers the steam to the combustor, and the steam turbo expander drives a second generator.

[0025] In another embodiment according to any of the previous embodiments, the electric power generated by the first and second generators is selectively supplied to the power grid. [[ID=I9]]

[0026] In another embodiment according to any of the previous embodiments, the bottoming cycle is provided with a bottoming fluid heated by passing through an evaporator, and the bottoming fluid downstream of the evaporator passes over a bottoming turbine. The bottoming fluid downstream of the bottoming turbine passes through a condenser and is cooled, and the bottoming fluid downstream of the condenser returns to the evaporator, and the bottoming turbine drives a third generator.

[0027] In another embodiment according to any of the previous embodiments, the electric power for driving the electrolysis system is supplied from a power source at a location external to the energy supply system. [[ID=2I]]

[0028] [[ID=I8]] In another embodiment according to any of the previous embodiments, water is separated from the combustion products, and the separated water returns to a second water supply source.

[0029] In another embodiment according to any of the previous embodiments, the steam turbo expander extracts work from the steam and then delivers the steam to the combustor. The steam turbo expander drives a second generator, and the electric power generated by the first generator and the second generator is supplied to the power grid.

[0030] The present disclosure may include any one or more of the individual features disclosed above and / or below, either alone or in any combination thereof.

[0031] These and other features of the invention will be best understood from the following specification and drawings, which are a brief description thereof.

Brief Description of the Drawings

[0032] [Figure 1A] [[ID=--]]A diagram showing a power system. [Figure 1B] A diagram showing a heat exchanger of a different embodiment that preheats both water and oxygen. [Figure 2] A diagram showing an electrolysis system used in combination with the system of FIG. 1. [Figure 3] A control flowchart.

Modes for Carrying Out the Invention

[0033] The power system 20 is shown in FIG. 1A. The combustor 22 receives a hydrogen source 51 via line 49 and an oxygen source 46 via line 50. The hydrogen and oxygen can be maintained at extremely low temperatures so as to be in a liquid state. Alternatively, the hydrogen and oxygen may be in a gaseous state. The hydrogen and oxygen are mixed and ignited within the combustor 22. <000-]]

[0034] From the combustor 22, the combustion products pass downstream beyond the turbine rotor 24 and drive the shaft 25 to rotate. The generator 26 is shown schematically, and electric power is generated by the rotation of the shaft 25. The electric power can be supplied to an application 116, such as a power grid.

[0035] The combustion products also pass through the evaporator 28 and an optional condenser 42. Downstream of the condenser 42, the combustion products The object Exiting the system. Ideally, there should be virtually no combustion products at point 43, but in reality, small amounts of liquid water or vapor may be present.

[0036] The evaporator 28 heats water from a water supply source 54 that passes through line 58. A pump 56 can drive the water. The heated water turns into steam and is delivered to the combustor 22 in line 60.

[0037] The heated water is also sent to the turbine 24 via line 62. Valve 59 controls this flow rate. Steam and / or water are sent to the turbine 24 for buffer flow or cooling. Valve 59 controls the steam flow rate between the turbine and the combustor, and can control combustion limits such as combustion temperature, the need to cool the turbine, and concerns about extinguishing the flame if too much steam is added.

[0038] The branch line 64 branches off from the feedwater line upstream of the evaporator 28, supplying unheated water to a position midway between the combustor 22 and the turbine 24. Valve 57 controls this flow rate. Valve 57 controls the ratio of steam to water. Water may be useful for specific cooling purposes within the turbine. Secondly, this allows some of the water to bypass the evaporator. The control ensures that lines 60 and 62 contain only steam. If too much water is sent to the evaporator and some does not boil, the liquid water may enter unintended locations, such as the turboexpander 202.

[0039] An optional bottoming main cycle 30 includes a bottoming turbine 32 and a water supply source 34. A pump 36 drives water through an evaporator 28 in line 38. This water is heated to steam, which drives the turbine 32. As shown, a generator 40 generates electricity from the rotation of the turbine 32. Downstream of the turbine 32, water is supplied to the line 10Return to water source 34 via this route.

[0040] The control of the valves, the power supply to the grid, and the flow rate and operation of the entire system 20 can be incorporated into the overall grid power control, as illustrated in Figure 2.

[0041] A steam turboexpander 202 is located on line 60 and expands the steam delivered to the combustor 22. The turboexpander 202 drives a generator 203, which can also supply power to application 116 (e.g., a power grid).

[0042] Generators 26, 40, and 203 may be used to generate electricity at times when electricity is needed by power grids 116, etc., as schematically shown.

[0043] The water supply source 54 may be partially received in line 52 from water separated from the combustion products in the condenser 42. An alternative steam source 299 may be supplied to the combustor 22 rather than from the evaporator 28. For example, a separate boiler 301 may be used.

[0044] An additional cooling fluid source 55 may pass through the condenser 42. This additional source may be air or environmental water such as river water. It further serves to cool the combustion products, remove more water, and reduce the residual combustion products that reach point 43.

[0045] Line 44 from oxygen source 46 passes through condenser 42 and is heated by combustion products. Pump 53 is a pressure source for driving the heated oxygen into combustor 22. Similarly, hydrogen from hydrogen source 51 passes through condenser 42 in line 48. Pump 47 is a pressure source for driving the heated hydrogen into combustor 22.

[0046] Figure 1B shows another embodiment 210 for heat exchange between fluids. In embodiment 210, steam generation from the water supply source 216 to the combustor 22 via line 160 passes through a heat exchanger 214. The heat exchanger 214 can generally be located where the evaporator 28 is. Combustion products in 212 spread across the heat exchanger 214, heating the water from the water supply source 216 and producing steam in line 160. Line 144 further passes oxygen from the oxygen source 46 through this same heat exchanger 214 to be preheated by the combustion products. Similarly, line 148 connects to a hydrogen source 51, which is preheated in the heat exchanger 214.

[0047] In other words, in the embodiment of Figure 1A, two heat exchangers perform steam generation and preheating functions, but both functions can also be performed by a single heat exchanger. Embodiment 210 may otherwise operate similarly to the system in Figure 1A. In other words, if water is available without a condenser, for example, preheating of the fuel and oxidizer can be performed instead in the evaporator.

[0048] The entire system 20 provides highly efficient power generation. Using liquid hydrogen and liquid oxygen provides more efficient power generation than using gaseous oxygen and hydrogen. However, the energy cost of liquefying gaseous oxygen and hydrogen may suggest the need to utilize gaseous oxygen and hydrogen.

[0049] A more reliable power generation system is needed. The system of this disclosure generally relies on established and known technologies, but can still be assembled in its own configuration.

[0050] Large-scale battery systems are often considered as an alternative source for generating large amounts of electricity. However, such technologies still need to be developed. Furthermore, system 20 of this disclosure relies on more commonly available materials compared to the materials required for such proposed battery systems. In electric vehicles and other proposed electrical systems, battery materials such as lithium are more difficult to obtain in sufficient quantities for widespread use in grid-scale energy storage because they are competitively pursued in other applications.

[0051] Furthermore, net water usage is zero or near zero. The small amount of water emitted from the system may be in liquid form. Water vapor is a greenhouse gas in the atmosphere, but it is not substantially emitted from this system. Therefore, greenhouse gas emissions are zero.

[0052] Furthermore, greenhouse gas emissions are zero. In the proposed system, power generation from hydrogen exceeds 70% in overall efficiency. This is far higher than fuel cells, industrial gas turbines, and the like. In addition, the system 20 of this disclosure can quickly switch on and shut off power as needed to supply power intermittently generated from renewable sources.

[0053] As shown in Figure 2, the power grid 116 is illustrated. System 20 is shown to supply power to the power grid 116 at 114.

[0054] Other conventional power sources, such as the wind turbine 102, also supply power to the power grid 116. Although a wind turbine is shown, it should be understood that all power sources, including standard power plants, are considered part of the power generation system 102. Here, a water source 105 is shown that supplies water to the electrolysis system 107. The energy of 104 can be provided by the conventional power generation system 102, which powers the electrolysis system 107 by decomposing the water 105 into hydrogen components 108 and oxygen components 109.

[0055] The electrolysis system 107 may be a known one. These components are supplied to storage sources 51 and 46, respectively, in 110 and 112. Components 108 and 109 may be liquefied by the refrigerant system 200 and stored in the liquid phase in 51 and 46. Waste heat from the refrigerant system 200 may be reused in various parts of the process, such as when preheating water for electrolysis. The reuse of the refrigerant system 200 and waste heat may be as known.

[0056] As shown in this figure, the water supply source 105 may be supplied from a return line 106 from system 20. In that sense, the water circuit here may be a closed loop. On the other hand, an open-loop system is also within the scope of this disclosure.

[0057] As described above, the controller 400 of the system shown in Figure 2 controls the power generation system 20, the electrolysis process 107, and all operations disclosed throughout the entire system shown in Figure 2. The proposed operation method is disclosed below, and it should be understood that the controller 400 is programmed to influence the operation and control shown in Figure 3.

[0058] A flowchart for operating the system shown in Figure 2 is disclosed in Figure 3. Generally, power generation by the electrolysis system 107 and system 20 cannot occur simultaneously. For example, if the energy generated by energy source 102 is less than the demand of grid 116, system 20 will operate to supply additional power at 114. However, if the energy generated by energy source 102 exceeds the demand of grid 116, the surplus energy will be used at 104 to drive the electrolysis system 107. Therefore, the operating system in Figure 3 is configured to ensure stable grid operation.

[0059] In that sense, the generated oxygen 109 and hydrogen 108 may be stored in a liquid state or similar for a certain period until power generation is needed, after which the oxygen and hydrogen are sent to the combustor 22.

[0060] Figure 3 shows a flowchart. In step 300, the controller 400 monitors the amount of power generated by system 102. In step 302, the controller 400 monitors the power demand of grid 116. In step 304, the controller 400 determines whether the monitored power generation is equal to the grid demand. If the answer is "yes", in step 306 the system returns to step 300.

[0061] If the controller 400 determines in step 304 that the monitored generated power is not equal to the grid demand, then in step 308 the controller 400 determines whether the monitored generated power exceeds the demand of grid 116.

[0062] Based on the determination that a surplus of power is generated, in step 312, the controller 400 supplies power to 104 to operate the electrolysis system 107. As described above, the power supply system 20 is preferably not operated during this step.

[0063] If the determination in step 308 is that the power generated does not exceed grid demand, the controller 400 determines that the power generated is less than the demand. Based on this determination, in step 316, the controller 400 generates power from system 20 and shuts off the electrolysis system 107.

[0064] The hydrogen / oxygen engine of this disclosure has higher thermal efficiency than existing power generation systems such as combined cycle gas turbines or fuel cells. One reason for this is the absence of gaseous nitrogen compression, which does not supply the corresponding power in such systems. However, the combustion temperatures of pure H2 and O2 are high. Therefore, the injection of steam lowers the temperature, helping the combustor to be maintained at a more manageable temperature.

[0065] The proposed system improves upon conventional technology in several ways. First, by injecting steam into the combustor, the combustor can withstand the expectedly very high temperatures.

[0066] Furthermore, the proposed system enhances its efficiency by generating the heat of such steam from an evaporator heated by waste heat from the turbine 24. Additionally, the use of liquid hydrogen and liquid oxygen to condense the water, with the heat of condensation recovered in the combustor 22, further increasing the efficiency of the system 20.

[0067] In addition, preheating the liquid oxygen and hydrogen supplied to the combustor provides advantages that surpass conventional technologies.

[0068] A further advantage is that this system reduces greenhouse gas emissions compared to conventional power generation systems.

[0069] In this disclosure, the energy supply system can be said to include an electrolytic system for electrolyzing a first water source and splitting the water into hydrogen and oxygen components. The hydrogen and oxygen components are supplied to a power generation system. The power generation system includes a combustor that receives the hydrogen and oxygen components and is operable to burn them. The combustor also receives a steam source. The combustion products downstream of the combustor pass over a top turbine rotor, driving the top turbine rotor to rotate. The first generator generates electricity from the rotation of the top turbine rotor.

[0070] While embodiments of this disclosure are shown, those skilled in the art will recognize that modifications will fall within the scope of this disclosure. Therefore, the following claims should be studied to determine the true scope and content of this disclosure.

Claims

1. An electrolysis system for performing electrolysis on a first water supply source and decomposing water into hydrogen and oxygen components, The hydrogen and oxygen components are supplied to the power generation system. The power generation system includes a combustor, which is capable of receiving the hydrogen and oxygen components and burning the hydrogen and oxygen components. The electrolytic system and, Combustion products flow downstream from the combustor, passing over the top turbine rotor to rotate the top turbine rotor, and further downstream, A first generator for generating electricity from the rotation of the top turbine rotor, An evaporator positioned to receive the combustion products downstream of the top turbine rotor, A condenser is positioned to receive the combustion products that have passed through the evaporator from the downstream side of the evaporator, and condenses the combustion products into liquid water by cooling them with a cooling fluid. Includes, The liquid water supplied from the condenser is sent to a second water supply source, the liquid water is sent from the second water supply source to a pressurizing pump and supplied to the evaporator, and as the liquid water passes through the evaporator, the combustion products boil the liquid water passing through the evaporator and supply the liquid water passing through the evaporator to the combustor as steam. The combustion products in the condenser are used to preheat the hydrogen and oxygen components that are sent to the combustor, in an energy supply system.

2. The energy supply system according to claim 1, wherein the liquid water recovered from the combustion products in the condenser is further sent to the first water supply source.

3. The energy supply system according to claim 1, wherein the steam is selectively injected into the top turbine rotor.

4. The energy supply system according to claim 1, wherein the liquid water from the second water source is selectively delivered into the combustion product between the combustor and the top turbine rotor.

5. The controller controls the electrolysis system and the power generation system. It is programmed to monitor the amount of electricity generated by other power generation systems. It is programmed to monitor the power demand of the power grid, Based on the determination that the amount of power generated exceeds the power demand of the system, the electrolysis system is activated and the power generation system is engaged or disengaged. Based on the determination that the amount of electricity generated is less than the determined electricity demand of the system, the operation of the electrolysis system is stopped and electricity is generated from the power generation system. The energy supply system according to claim 1, which is programmed to perform at least one of the following.

6. The energy supply system according to claim 1, wherein the hydrogen and oxygen components are cooled to a liquid state and stored before being supplied to the combustor.

7. The energy supply system according to claim 6, wherein the hydrogen and oxygen components are preheated before being delivered to the combustor.

8. The energy supply system according to claim 1, wherein the hydrogen and oxygen components are preheated before being delivered to the combustor.

9. The energy supply system according to claim 8, wherein the combustion products are used to preheat the hydrogen and oxygen components.

10. The energy supply system according to claim 8, wherein the preheating of the oxygen and hydrogen components occurs in the evaporator.

11. The energy supply system according to claim 1, wherein the steam turboexpander extracts work from the steam and then delivers the steam to the combustor, and the steam turboexpander drives a second generator.

12. The energy supply system according to claim 11, wherein the electricity generated by the first generator and the second generator is selectively supplied to the power grid.

13. The energy supply system according to claim 1, wherein the bottoming cycle is supplied with a bottoming fluid heated by passing through the evaporator, the bottoming fluid downstream of the evaporator passes over a bottoming turbine, the bottoming fluid downstream of the bottoming turbine passes through a condenser to be cooled, the bottoming fluid downstream of the condenser returns to the evaporator, and the bottoming turbine drives a third generator.

14. The energy supply system according to claim 1, wherein the power to drive the electrolysis system is supplied from a power source located outside the energy supply system.

15. The energy supply system according to claim 1, wherein a steam turbo expander extracts work from the steam and then delivers the steam to the combustor, the steam turbo expander drives a second generator, and the electricity generated by the first generator and the second generator is supplied to the power grid.

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