Embodiments of the invention and methods of use relate to the production of hydrogen (H2) and carbon monoxide (CO) and, in particular, to the production of hydrogen and carbon monoxide from water and/or steam and/or carbon dioxide. The hydrogen and carbon monoxide may be used in chemical and/or fuel production.
Solid-oxide electrolysis cells are able to electrolytically reduce and split water and carbon dioxide into carbon monoxide, hydrogen and oxygen. These cells require energy in order to generate carbon monoxide, hydrogen and oxygen. Thusly, water and carbon dioxide may be converted into carbon monoxide, hydrogen, and oxygen, which may be combined to form a synthetic gas (syngas) or reacted to form synthetic fuels (synfuels) and other useful products using, for example, heat and electricity. When operated as a solid-oxide electrolysis cell, the anode of the cell is the oxidant-side electrode and the cathode is the reducing electrode. An electrolyte separates the anode from the cathode. The energy required to drive the reduction reaction can be provided by electricity and/or heat. That is, as temperature increases, the amount of electricity required linearly reduces as the temperature linearly increases. As described in U.S. patent application Ser. No. 15/480,622 filed Apr. 6, 2017, (the '622 patent application) solar energy provides heat through the received solar energy at a Fresnel lens within the infrared (IR) regions and electricity from conversion of light within the ultraviolet (UV) and visible regions via a high efficiency hybrid solar energy concentrator device. Therefore, through concentration and separating the IR from the visible and UV light spectra, the solid-oxide electrolysis process can be improved using a decentralized, compact electrolysis unit such as the solid-oxide electrolysis cell described herein combined with a compact hybrid solar concentrator as described by the '622 patent application for generating at least heat and electricity. Furthermore, the production of hydrogen through the solid-oxide electrolysis cell can be run in reverse to efficiently generate pure water and electricity. Likewise, controlled combustion of hydrogen in oxygen can alternatively produce water and electricity by capturing the products of the combustion reaction and harnessing the work of expansion due to the combustion of the hydrogen gas into water,
The preceding and following discussion of the solar energy and electrochemistry arts comprising renewable energy generators and electrolysis cells should not be construed as an admission that the subject matter of the discussion is known to others.
Solid-oxide electrolysis cells may be used for high temperature electrolysis of water and carbon dioxide into hydrogen and carbon monoxide. Therefore, it would be beneficial to develop systems and methods for converting water and carbon dioxide into hydrogen and carbon monoxide for use in various fuels or alkyl-based products. The use of heat and electricity derived from renewable solar energy power makes a distributed or enhanced version of such systems, even in remote areas. Further, the generated hydrogen can be used as a storage medium for both water and electricity for later use in that remote location or another location. Here, renewable solar energy increases the efficiency of developing hydrogen as a storage medium. Therefore, the system allows for the production of fuels and/or products via a combined renewable energy generator and an electrolysis cell. Presently, no efficient combination or a renewable energy device and an electrolysis cell is known to be compact, efficient, and distributed. Furthermore, presently, there are known problems which exist with known choices of materials for electrolyte, cathode and anode.
The problems associated with providing sophisticated, efficient solid-oxide electrolysis cells either completely or partially powered by solar power in a maintainable, distributed, compact unit is solved by the methods and embodiments of the present invention. According to embodiments and methods of the invention, hydrogen (H2) and carbon monoxide (CO) may be formed from water (H2O) and/or steam (H2O) and carbon dioxide (CO2) using a solid-oxide electrolysis cell to decompose the water to hydrogen and oxygen, to decompose carbon dioxide to carbon monoxide and oxygen, and to react carbon dioxide with at least some of the produced hydrogen to form water and carbon monoxide powered by renewable solar energy. The hydrogen and carbon monoxide produced according to embodiments of the invention may be used as synthetic gas (syngas) components for the production of synthetic fuels (synfuels) and other products according to conventional methods. A solid-oxide electrolysis cell or array of cells may be fed electricity or heat from a renewable energy solar cell or array of solar cells. A hybrid solar concentrator is particularly useful for its capability of generating heat and/or electricity from solar power.
Solid-oxide electrolysis cells suitable for use with embodiments of the invention may include a porous cathode, a gas-tight electrolyte, and a porous anode. A power source such as a hybrid solar energy concentrator device for providing an electrical current across a solid-oxide electrolysis cell via a photovoltaic (PV) cell or integrated circuit or heat collector from collection of infrared light may also be incorporated with embodiments of the invention. The solid-oxide electrolysis cells used with particular embodiments of the invention may include any conventional solid-oxide electrolysis cell and any conventional materials such as zirconium dioxide for an electrolyte used to form the cathodes, anodes, and electrolytes of such solid-oxide electrolysis cells. On the other hand, yttria stabilized zirconia is a recommended electrolyte. Nickel zirconia cermet (ceramic and metal) is a recommended material for the cathode. Strontium-doped lanthanum manganite is a recommended material for the anode. These overcome deficiencies of known materials used.
In some embodiments of the invention, solid-oxide electrolysis cells may be grouped together to create one or more arrays of solid-oxide electrolysis cells, completely or partially powered by one or more sources of solar energy or other compact, reliable, efficient source of renewable energy for generating especially heat and electricity in the form of solar cell arrays. Water, such as water in the form of, preferably, high temperature steam, may be fed to the arrays of solid-oxide electrolysis cells where the water (steam) comes into contact with a cathode side of the solid-oxide electrolysis cells. An electrical current in the cathode of a solid-oxide electrolysis cell facilitates the decomposition of water into hydrogen and oxygen ions (O2). Carbon dioxide (CO2) may also be fed to the arrays of solid-oxide electrolysis cells, which may result in the decomposition of carbon dioxide into carbon monoxide (CO) and oxygen ions. The oxygen ions pass through an electrolyte to an anode of the solid-oxide electrolysis cell where the oxygen ions combine to form oxygen (O2), releasing electrons. The oxygen may be collected as a product stream of the process. The hydrogen and carbon monoxide may not pass through the electrolyte and may be collected as a useful product stream of the process.
In other embodiments of the invention, carbon dioxide may be introduced to the cathode side of a solid-oxide electrolysis cell with water, or steam. The carbon dioxide may react with hydrogen formed by the decomposition of water on the cathode side of the solid-oxide electrolysis cell. Reaction of carbon dioxide with hydrogen forms water and carbon monoxide. The water may be further decomposed into hydrogen and oxygen according to embodiments of the invention. The carbon monoxide formed by the reaction of carbon dioxide with hydrogen may be collected as another useful product of the process.
According to embodiments of the invention, carbon monoxide and hydrogen collected from the decomposition of water, carbon dioxide, or a combination of water and carbon dioxide and the reaction of carbon dioxide with hydrogen may be collected, stored, or otherwise provided to a synfuels production process. As noted previously, syngas is comprised of carbon monoxide and hydrogen. The syngas components produced by embodiments of the invention may be used to form synfuels according to conventional methods. Syngas or synfuels may be used locally, for example, at a remote location (such as a remote African, Australian or South American village) or transported to another location by conventional pipelines or vehicular or other transportation methods.
According to particular embodiments of the invention, at least a portion of the feed streams, or at least a portion of the energy required to convert water and carbon dioxide to syngas components, hydrogen and carbon monoxide, are preferably provided by a radiant renewable energy power process or a process utilizing radiant power to produce the desired feed streams or energy. In some embodiments, radiant power, via an infrared light collection, heat being received via the collected IR energy, may be used to generate steam, which steam may be used as a water source for the production of syngas by the solid-oxide electrolysis cells. Steam produced by the radiant power process may also be used to heat the feed streams, the solid-oxide electrolysis cells, the product streams, or combinations thereof, to provide process temperatures above, for example, at least about 250° C., preferably 500° C. to 1000° C. Electricity produced by the radiant power process may also be used to provide heat to particular portions of the process and/or to provide electrical current required for operation of the solid-oxide electrolysis cells. Electricity and steam generated by the radiant process may also be used to promote a combustion process for the formation of carbon dioxide, such as by the combustion of fuels, wastes, for example, comprising carbon, or other products or materials found at the remote location. The produced carbon dioxide may then be used as a feed source for embodiments of the invention. In still other embodiments of the invention, carbon dioxide may be provided to a solid-oxide electrolysis cell from a carbon dioxide source. For example, stored carbon dioxide, in liquid, solid, or gaseous form, may be used as a carbon dioxide source. Carbon dioxide produced by combustion processes, such as by the burning of fuels, wastes, or other materials, by biological reduction processes, or by manufacturing processes, such as by the production of cement clinker, for example, formed by heating ground limestone with clay (and a small amount of gypsum) at temperatures in excess of 1000° C. or petrochemical refining processes, wherein carbon dioxide may be extracted from crude oil, may also be used with embodiments of the invention.
In still other embodiments of the invention, the generated hydrogen may be used for a storage medium for clean water and electricity. For example, the combustion of hydrogen produces water directly while energy can be generated as a result of the expansion of the combusted gases and converted into electrical energy. Alternatively, an electrolytic cell can be run in reverse wherein hydrogen and oxygen are fed into the system to generate water and electricity. As a result, hydrogen can be used as a storage medium for water and power for later use and if required the storage medium can be transported from one location to another for subsequent use. In summary, a hybrid solar concentrator device or array of such devices may provide electricity and heat or high temperature steam necessary for operating a solid-oxide electrolysis cell or array of cells to, for example, produce hydrogen, water, carbon dioxide, carbon monoxide, syngas and synfuels in remote locations, typically off the electrical grid.
Now, a solar-enhanced, high temperature electrolysis process and apparatus will be described with reference to the incorporated-by-reference patent application and following discussion of its use as an array or singularly with a solid-oxide electrolysis cell or array of cells to produce useful products at a remote location that may be off the electric grid where a solar cell and solid-oxide electrolysis cell may provide a compact, high efficient apparatus for producing the useful products.
A detailed description of the drawings follows.
An embodiment of a high efficiency hybrid solar concentrator combined with a solid-oxide electrolysis cell may be described by way of introduction to what may be referred to as the five C's: capture, concentrate, collimate and constructively convert. See the '622 patent application incorporated by reference herein in its entirety for a more complete discussion of a high efficiency hybrid solar concentrator device for use, for example, at remote locations. Firstly, capture has as an object to capture diffuse light and solar origin light. In connection with one embodiment of the present invention and referring to FIG. 1 of either the '622 patent application (renumbered
A high-magnification solar concentrator per FIGS.5-15 of the '622 patent application (renumbered
The second C stands for a collimator or Fresnel lens 15 of
A spectrum separator 40 may be a cold (or hot) mirror having a dichroic film. In at least one embodiment, UV and visible solar radiation is separated from infrared solar energy. The UV/visible light energy is passed to a UV/visible photovoltaic device which may be, for example, ten millimeters in diameter (circular) or, in another example, ten millimeters square or comprise one square centimeter, approximately, for ideally receiving an even uniformity of both bandwidths across the UV/visible spectra and intensity.
On the other hand, the spectrum separator 40 may comprise a dichroic film for passing infrared radiation to an infrared photovoltaic cell of similar size to that of the UV/visible PV cell or ten millimeters by ten millimeters (one centimeter in diameter if circular or one centimeter square if square) or the heat collector and transporter device of similar size (for example, a copper plate and insulated copper wires). The concentrated light is split into UV/visible light and infrared radiation. The UV/visible light is directed to a double junction PV cell or integrated circuit assembly which may convert fifty-three percent of the UV/visible light into electricity. The infrared radiation may be directed to a p/n junction cell which may convert approximately thirty percent of infrared radiation into electricity. Conventional PV and concentrated PV (CPV) efficiency is reduced by the thermal effects of infrared photons. Thus, infrared radiation reduces efficiency by increasing the temperature of the cell which in turn reduces effective conduction of electrons thus reducing efficiency by ten to twenty-five percent on hot days. On the other hand, the infrared heat increase may be used to advantage to heat water into high. temperature steam for operating the solid-oxide electrolysis cell or array. As a result of the five Cs approach, the embodiments described herein may operate at a concentration ratio of approximately one thousand five hundred suns (or one thousand five hundred magnification), or even two thousand suns and generate electricity (using both infrared and UV/visible cells) at an efficiency of approximately forty percent compared with the state-of-the art eighteen percent. The generation of heat for developing steam that may be used in a number of ways is made possible by the spectrum separator 40 directing infrared (heat) to a heat collector and transported to the solid-oxide electrolytic cell or array of cells,
FIG. 1 of the '622 patent application (renumbered
The different systems of FIGS. 1, 2 and 3 of the '622 patent application (now
Furthermore, for example, a converging Fresnel lens 20 may multiply the electromagnetic radiation it receives directly from the sun source one thousand times or from the collimator 15 by a further predetermined factor. In one example, if collimator 15 multiplies by up to ten or more and converging Fresnel lens 20 by up to one hundred or more then, incident radiant energy is multiplied by a total factor of up to one thousand or more. In an alternative embodiment, the concentrating Fresnel lens 20 may be a shaped Fresnel lens; (see the converging dome-shaped lens of FIGS. 6 and 7 shown in the '622 patent, now
The domed-shaped, circular and square Fresnel lens may be 400 mm×400 mm×3 millimeters and be manufactured of Polymethyl Methacrylate, a form of plastic. A cold mirror at either 35 mm×35 mm×3.3 mm or 25×25×3.3 mm may be constructed of borofloat glass from Schott A G of Mainz, Germany, with a dichroic film coating to reflect a preferred band, for example, IR and pass UV/visible. A custom negative lens may be matched with a domed Fresnel lens and a cold mirror at 35×35 millimeters and dimension A from the Fresnel lens to the detector is 419.5. Dimension B is the distance from the vertex of the custom negative lens to the detector at 39 millimeters and dimension C may be the midpoint between the cold mirror and the detector or sixteen millimeters.
A conventional flat lens has been compared with a dome-shaped lens on a flat Fresnel lens surface and a twenty-five millimeters by twenty-five millimeters cold mirror and with a thirty-five millimeters by thirty-five millimeters cold mirror. With a 35×35 mm cold mirror, efficiency of energy conversion was greatly improved with a 10 mm×10 mm PV UV/visible detector. The hybrid solar concentrator provides high efficiency, low failure rate solar energy conversion in two separate solar bands, infrared (IR) and ultraviolet (UV)/visible to produce heat and/or electricity.
When a Fresnel lens is used as a concentrator, due to the light focusing characteristic of the Fresnel lens, a Fresnel lens is desirably used in conjunction with a motor system 80 or a plurality of light reflectors, not shown, for collecting and delivering the light to Fresnel lens 20 so that it may be further delivered without loss of radiant energy to system 30, 40, 50, 60, 70. The converging Fresnel lens 20, for example, may transmit light it receives onto a diverging Fresnel lens 30.
Converging Fresnel lens 20 and all elements shown below the Fresnel lens 20 in FIGS. 1 and 2 through 3C of the '622 patent application (now
A plurality of stacked hot or cool spectrum separators, for example, dichroic lenses, 40 may receive light and transmit or reflect the light at different spectral bands to different photovoltaic cells or accumulators operable at different spectral bands at different receiving locations or may collect heat. On the other hand, infrared light may be reflected from the dichroic lens 40 either onto an accumulator 70, a further collimator, not shown, or is focused through an IR Fresnel lens 60 onto an accumulator 70. The accumulator 70 then may, for example, use heat to either distill liquid, expand a working fluid, produce mechanical energy, generate thermal energy, convert hazardous and carbon-containing waste into fuel and/or generate electrical energy. Hazardous waste that is radio-active may be separated such that the radioactive elements may be used to fuel a nuclear energy plant.
One or a plurality of embodiments of a system such as may be seen in FIG. 4(A) through FIG. 4(C) of the '622 patent application (now
A model of an embodiment of a high efficiency hybrid solar concentrator and the performance of heat management arc discussed with reference to FIGS. 6 through 11 of the '622 patent application (now
FIG. 7 of the '622 patent application (now
Thus, there has been shown and described a method for producing one or more of Hydrogen, Oxygen, water, steam, syngas, synfuels, carbon dioxide and carbon monoxide. Hydrogen may be used in remote locations to use to generate clean water and electricity for use. The hydrogen and carbon monoxide may be routed to a synfuel production process. The production method may comprise directly exposing one or more of water, steam and carbon dioxide to heat generated by a radiant power source and collected by a renewable energy generator to produce a feed stream comprising one of steam at a high temperature (such as at least 250° C.) and carbon dioxide. Carbon dioxide may be produced by combusting materials such as carbon monoxide using the heat generated by the radiant heat and/or electrical power source. In the alternative, a carbon dioxide source (not shown) may be used to supply the carbon dioxide, wherein the carbon dioxide source is selected from the group consisting of a combustion process, a cement clinker process (heating ground limestone and clay at high temperature), a petrochemical refining process and a carbon dioxide storage facility. On the other hand, one may then introduce the feed stream to a cathode side of at least one solid-oxide electrolysis cell to decompose the steam into hydrogen and oxygen ions and the carbon dioxide of the feed stream into carbon monoxide, one may then provide an electrical current produced by the renewable energy generator to the at least one solid-oxide electrolysis cell. As a result, one may select a magnitude of an electrical current output of the radiant power source as well as hot steam provided to the at least one solid-oxide electrolysis cell to produce the hydrogen and the carbon monoxide.
The radiant power source or renewable power generator may be selected from the group consisting of renewable solar power generators, lasers, and ambient light from light sources.
All patents and articles referenced herein should be deemed to be incorporated herein by reference in their entirety as to their entire subject matter. One of ordinary skill in the art should only deem the several embodiments of a solar concentrator and conversion apparatus and method described above to be limited by the scope of the claims which follow.
A method for producing one or more of Hydrogen, Oxygen and Carbon Monoxide, the method comprising:
This is a continuation-in-part of U.S. application Ser. No. 15/480,622, entitled “High Efficiency Hybrid Solar Energy Device,” filed Apr. 6, 2017, by Reginald Parker et al., and of U.S. patent application Ser. No. 16/588,290 filed Sep. 30, 2019, entitled “Upconverted Hybrid Solar Energy Device” of the same inventor. This application also claims the benefit of the right of priority to U. S. Provisional Patent Application Ser. No. 62/780,424, filed Dec. 17, 2018. All the above-identified patent applications are incorporated by reference herein in their entirety.
Number | Date | Country | |
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62780424 | Dec 2018 | US |
Number | Date | Country | |
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Parent | 15480622 | Apr 2017 | US |
Child | 16717894 | US | |
Parent | 16588290 | Sep 2019 | US |
Child | 15480622 | US |