WO2025181687A1 - Systems and methods for synthesis of steel using green hydrogen - Google Patents

Abstract

The present disclosure provides a system and a method for steel synthesis using green hydrogen by coupling renewable energy and Carnot batteries with Solid-Oxide Electrolyser Cells (SOEC) and carbon capture. The system provides an end-to-end, geography-agnostic solution for steel synthesis with green hydrogen with round-the-clock renewable energy using Carnot battery that provides both heat and power to run an SOEC at a high efficiency. The hydrogen from the SOEC may be used for direct reduction of iron followed by steel synthesis in an Electric Arc Furnace. The heat from the SOEC is also used for capturing CO2 from the exhaust gases (or air in the DAC configuration). The captured CO2 may be used for electrofuels synthesis along with green hydrogen or electrochemically reduced to carbon. The process heat from DRI and EAF is recycled back to the Carnot batteries.

Description

SYSTEMS AND METHODS FOR SYNTHESIS OF STEEL USING

GREEN HYDROGEN

TECHNICAL FIELD

[0001] The present disclosure relates to the field of synthesis of steel using green hydrogen. More particularly, the present disclosure relates to a system and a method for steel synthesis by coupling renewable energy and Carnot batteries with Solid-Oxide Electrolyser Cells (SOEC) and CO2 capture.

BACKGROUND

[0002] The following description of related art is intended to provide background information pertaining to the field of the disclosure. This section may include certain aspects of the art that may be related to various features of the present disclosure. However, it should be appreciated that this section be used only to enhance the understanding of the reader with respect to the present disclosure, and not as admissions of prior art.

[0003] Historically, steel production from iron ore has been done by reducing the ore using high-grade coal which is a finite and non-renewable resource. However, the environmental concerns associated with extraction and combustion of fossil fuels, including greenhouse gas emissions and climate change have spurred significant interest in developing alternative and sustainable methods for steel production. A promising approach is the utilization of renewable resources, such as green hydrogen (H₂) to synthesize steel through environment- friendly processes.

[0004] Green hydrogen is produced by electrolysis of water using renewable energy. There are many challenges with the large-scale production of green hydrogen. Renewables such as solar and wind are intermittent, therefore, hydrogen production, when directly coupled with these renewables, is limited to a few hours per day. Round-the-clock renewables such as hydropower are limited by geography. Further, most commonly used electrolysers, alkaline and proton exchange membrane electrolysers, have modest efficiencies (e.g., 55 - 65 %). When coupled directly with intermittent renewables, these electrolysers can only function for a few hours per day and thus need to be oversized by two-three times. Furthermore, to utilize green hydrogen for production of green steel, a reactor is required. These reactors are usually designed to run at all times. So, when hydrogen production is coupled with intermittent renewables, either the reactors have to be oversized and designed to run intermittently, or hydrogen has to be stored for long hours which is very expensive and inconvenient. Therefore, the green hydrogen synthesis suffers from limitations imposed by intermittency of renewable energy availability and lack of widespread round-the-clock renewable energy, low- efficiency of commonly used electrolysers, and high costs associated with storage.

[0005] Further, the high temperatures in an Electric Arc Furnace (EAF) (1, 500-1, 600°C) required for steel synthesis need round-the-clock renewable power. Round-the-clock power is also required for other processes such as heating of iron ore and hydrogen to high temperatures before feeding for direct reduction of iron ore (DRI) reactor.

[0006] Further, for steel synthesis using green hydrogen, a small amount of carbon is still required in the EAF for carburization, slag foaming and reduction of any remaining iron oxide.

[0007] There is, therefore, a need to overcome at least the above-mentioned drawbacks, limitations, and shortcomings, and provide an efficient solution for steel synthesis using green hydrogen.

OBJECTS OF THE PRESENT DISCLOSURE

[0008] Some of the objects of the present disclosure, which at least one embodiment herein satisfies are as listed herein below.

[0009] An object of the present disclosure is to provide a system and method for synthesis of steel using green hydrogen.

[0010] Another object of the present disclosure is to provide a system and a method for synthesis of steel using direct reduction of iron ore (DRI) with green hydrogen followed by steel synthesis in an Electric Arc Furnace (EAF) with capture of carbon dioxide.

[0011] Still further object of the present disclosure is to provide a system and a method for steel synthesis by coupling renewable energy and Carnot batteries with Solid-Oxide Electrolyser Cells (SOEC) and CO2 capture.

[0012] Another object of the present disclosure is to combine renewable energy with Carnot batteries to provide round-the-clock power and heat to run the SOEC with high efficiency of more than 90% (up to 100%).

[0013] Another object of the present disclosure is to combine renewable energy with Carnot batteries to provide round-the-clock power and heat to run EAF and other processes such as heating of iron ore pellets and hydrogen.

[0014] Still another object of the present disclosure is to use the CO2 captured from the DRI-EAF process for electro-fuel synthesis along with green hydrogen produced from Carnot battery and SOECs. [0015] Another object of the present disclosure is to use round-the-clock power and heat for DAC to provide carbon dioxide which can then be reduced to pure carbon and used for carburization and slag foaming in green steel synthesis.

[0016] Further object of the present disclosure is to use the oxygen from SOEC for slag foaming in the EAF.

[0017] Another object of the present disclosure is to recycle the process heat from DRI and EAF to Carnot battery to reduce primary power consumption for heating and increase the total efficiency of the system.

[0018] Yet another objective of the present disclosure is to decarbonize steel production in existing or brownfield plants by capturing CO2 from the exhaust gases and utilizing it for synthesis of electrofuels (syngas, methane, methanol, ammonia, other FT fuels, etc.) by reacting it with green hydrogen produced by coupling renewables with Carnot battery and SOEC. The system would further decarbonize the brownfield steel plant by providing it with round-the-clock power and heat for its operations.

SUMMARY OF THE INVENTION

[0019] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in Detailed Description section. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0020] An aspect of the present disclosure is to provide a system (100) for steel synthesis comprising: a Carnot battery (104) configured to receive renewable power supply from one or more intermittent renewable sources (102); a solid-oxide electrolyser cell (SOEC) (106) coupled to Carnot battery (104) for producing hydrogen; a direct reduction of iron ore (DRI) reactor (112) configured for reducing the iron ore to a hot reduced iron using hydrogen; and an electric arc furnace (EAF) (116) configured for complete melting of iron and steel synthesis.

[0021] Another aspect of the present disclosure is to provide a method for steel synthesis comprising: a) receiving renewable power supply from one or more intermittent renewable sources (102) to a Carnot battery (104); b) providing continuous heat and power by Carnot battery (104) to SOEC (106) to produce hydrogen at a high efficiency of more than 90%; c) heating the hydrogen using energy from the renewables (102) and Carnot battery (104) to obtain heated hydrogen (110); d) utilizing the heated hydrogen (110) and iron ore pellets (114) in direct reduction of iron (112) to obtain a hot reduced iron; and e) feeding the hot reduced iron to an electric arc furnace (EAF) (116) with carbon supply for complete melting of iron at high temperature and steel synthesis.

[0022] Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF DRAWINGS

[0023] The accompanying drawings, which are incorporated herein, and constitute a part of this invention, illustrate exemplary embodiments of the disclosed methods and systems in which like reference numerals refer to the same parts throughout the different drawings. Components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. Some drawings may indicate the components using block diagrams and may not represent the internal circuitry of each component. It will be appreciated by those skilled in the art that invention of such drawings includes the invention of electrical components, electronic components or circuitry commonly used to implement such components.

[0024] FIG. 1A illustrates an example flow diagram 100A for steel synthesis at Greenfield plants with carbon dioxide capture, in accordance with embodiments of the present disclosure.

[0025] FIG. IB illustrates an example flow diagram 100B for steel synthesis at Greenfield plants with Direct Air Capture (DAC), in accordance with embodiments of the present disclosure.

[0026] FIG. 2 illustrates an example flow diagram 200 for decarbonizing steel production at existing plants at existing plants, in accordance with embodiments of the present disclosure.

DETAILED DESCRIPTION

[0027] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims. [0028] In the following description, numerous specific details are set forth in order to provide a thorough understanding of embodiments of the present invention. It will be apparent to one skilled in the art that embodiments of the present invention may be practiced without some of these specific details.

[0029] If the specification states a component or feature “may,” “can,” “could,” or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.

[0030] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.

[0031] The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. Further, the use of terms “first,” “second,” and “third,” and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another.

[0032] Moreover, in interpreting the specification, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a nonexclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refer to at least one of something selected from the group consisting of A, B, C . . . .and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc.

[0033] The use of any and all examples, or exemplary language (e.g., “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

[0034] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all groups used in the appended claims.

[0035] Embodiments of the present disclosure relate to a system and a method for producing steel by coupling renewable energy and Carnot batteries with solid-oxide electrolyser cells (SOEC) and carbon capture.

[0036] An embodiment of the present disclosure is to provide system (100) for steel synthesis comprising: a Carnot battery (104) configured to receive renewable power supply from one or more intermittent renewable sources (102); a solid-oxide electolyser cell (SOEC) (106) coupled to Carnot battery (104) for producing hydrogen; a direct reduction of iron ore (DRI) reactor (112) configured for reducing the iron ore to a hot reduced iron using hydrogen; and an electric arc furnace (EAF) (116) configured for complete melting of iron and steel synthesis.

[0037] In an embodiment, the Carnot battery (104) stores electricity in the form of thermal energy using processes such as but not limited to thermal energy storage, pumped thermal energy storage, and liquid air energy storage or a combination thereof during the charging cycle.

[0038] In an embodiment, the stored thermal energy is converted back into power (at an efficiency of 60-70%) along with usable heat during the discharge cycle (with the total efficiency of the Carnot Battery >90%), the power and heat are supplied to the SOEC and various other processes in steel synthesis.

[0039] In an embodiment, the oxygen produced by SOEC (106) is fed to the EAF (116) for slag foaming.

[0040] In an embodiment, the DRI (112) and EAF (116) produce surplus heat which is recycled to the Carnot battery (104) to be stored and used as dispatchable heat.

[0041] In an embodiment, the carbon is obtained from carbon dioxide captured by DAC (118) using power and heat from renewables (102) and the Carnot battery (104) followed by electrochemical reduction to carbon to be used in the electric arc furnace (116).

[0042] In an embodiment, the system is further applied to a conventional steel furnace using iron ore and coke (124) along with scrubbing of carbon dioxide from off-gas.

[0043] In an embodiment, the CO2 is captured from the EAF off-gas and used for electrofuels synthesis along with green hydrogen or electrochemically reduced to carbon.

[0044] Another embodiment of the present disclosure is to provide a method for steel synthesis comprising: a) receiving renewable power supply from one or more intermittent renewable sources (102) to a Carnot battery (104); b) providing continuous heat and power by Carnot battery (104) to SOEC (106) to produce hydrogen at a high efficiency of more than 90%; c) heating the hydrogen using energy from the renewables (102) and Carnot battery (104) to obtain a heated hydrogen (110); d) utilizing the heated hydrogen (110) and iron ore pellets (114) in direct reduction of iron (112) to obtain a hot reduced iron; and e) feeding the hot reduced iron to an electric arc furnace (EAF) (116) with carbon supply for complete melting of iron at high temperature and steel synthesis.

[0045] In an embodiment, the CO2 extraction (118) from the off gas of EAF for further electroreduction to carbon or use in electrofuels synthesis.

[0046] Various embodiments of the present disclosure will be explained in detail with reference to FIGs. 1 to 2.

[0047] FIG. 1A illustrates an example flow diagram (100A) for steel synthesis at greenfield plants with carbon capture, in accordance with embodiments of the present disclosure.

[0048] Referring to FIG. 1A, a Carnot battery (104) may receive renewable power supply from one or more intermittent renewable sources (102). In some embodiments, the one or more intermittent renewable sources (102) may include, but not limited to, solar and wind. Therefore, the Carnot battery (104) eliminates the problem of intermittency of renewables.

[0049] In some embodiments, the Carnot battery (104) may store electricity in the form of thermal energy using various processes such as, but not limited to, thermal energy storage, pumped thermal energy storage, and liquid air energy storage to produce hydrogen. The stored thermal energy is converted back to power using a heat engine (e.g., Brayton cycle, Rankine cycle, etc.). Residual thermal energy or heat is also available from this process, thus providing both dispatchable power and heat for a long duration. In some embodiments, the Carnot battery (104) may store electrical energy in the form of heat energy during a charging cycle. During the discharge cycle, the heat may be converted back to electricity, for example, at an efficiency of 60-70%. In some embodiments, the remaining heat is available for other purposes within the scope of the present disclosure. In some embodiments, the total efficiency (combined power and heat) of the Carnot battery (104) may be 100%.

[0050] The Carnot battery (104) may provide the heat and power to SOEC (106). The SOEC (106) may produce hydrogen at an efficiency of >90%. Further, the hydrogen from SOEC may be heated (110) using energy from the renewables (102) and the Carnot battery (104). The heated hydrogen (110) along with heated iron ore pellets (114) may be used for direct reduction of iron (112). The hot reduced iron thus produced may be fed to an electric arc furnace (116) for complete melting of iron at high temperatures and steel synthesis. Energy for heating the EAF is supplied by the renewables (102) and the Carnot battery (104).

[0051] The small amount of carbon required for carburization, slag foaming, and reduction of any remaining FeO may be provided from external sources (such as coal or biomass or electrochemically reduced CO2) to the electric arc furnace (116), wherein the CO2 (118) that is released is captured and used for synthesis of electrofuels along with green hydrogen from SOEC (106) or electro-reduced back to carbon to be recycled to the EAF.

[0052] The oxygen produced by SOEC may be fed to the EAF (116) along with carbon for slag foaming.

[0053] The surplus heat thus produced by the DRI and EAF may be recycled to the Carnot battery (104) to be stored and used as dispatchable heat or converted to power or other uses. This recycled heat may be at high temperatures (500-1000°C) and may be used to offset the primary heat requirement for heating of hydrogen.

[0054] Therefore, in greenfield plants, green steel is manufactured by direct reduction of iron ore in an atmosphere of green hydrogen followed by steel synthesis in an EAF. The carbon dioxide from the EAF is captured and used. Waste heat of steel synthesis is recycled back to the Carnot Battery (104).

[0055] FIG. IB illustrates an example flow diagram (100B) for steel synthesis at greenfield plants with DAC, in accordance with embodiments of the present disclosure. It may be appreciated that similar components have been references with same reference numerals as in FIG. 1A.

[0056] Referring to FIG. IB, the carbon is obtained from carbon dioxide captured by DAC using power and heat from renewables (102) and the Carnot battery (104) followed by electrochemical reduction to carbon to be used in the electric arc furnace (116). The CO2 (118) thus emitted by the furnace is neutral and has no Global Warming Potential (GWP). It may still be captured and used to make the system carbon negative. It may be readily appreciated that all other functionalities may be similar to the description corresponding to FIG. 1A, and hence, may not be described again for the sake of brevity.

[0057] FIG. 2 illustrates an example representation of a system (200) for decarbonizing steel production at existing plants, in accordance with embodiments of the present disclosure.

[0058] Referring to FIG. 2, the present system (200) may include the Carnot battery (104), and the SOEC (106) coupled to the Carnot battery (104). Further, the present system (200) may include a conventional steel furnace using iron ore and coke (124) along with scrubbing of carbon dioxide from off-gas. In some embodiments, the Carnot battery (104) may receive renewable power supply from one or more intermittent renewable sources (102).

[0059] In some embodiments, the Carnot battery (104) may store electricity in the form of heat thermal energy using various processes such as, but not limited to, thermal energy storage, pumped thermal energy storage, and liquid air energy storage to produce hydrogen. The stored thermal energy is converted back to power using a heat engine (e.g., Brayton cycle, Rankine cycle, etc.). Residual thermal energy or heat is also available from this process, thus providing both dispatchable power and heat for a long duration. The Carnot battery (104), along with renewables (102), may provide continuous heat and power to the SOEC (106) and for CO2 capture from the exhaust of the steel furnace. In some embodiments, the heat and power provided by the Carnot battery (104) and the renewables (102) may be used to run the SOEC (106) with high efficiency, for example, with more than 90% efficiency (up to 100%), as compared to conventional approaches. For example, the SOEC (106) may produce hydrogen with high efficiency. Due to the high efficiency of the SOEC (106), the remaining heat energy is utilized to capture carbon dioxide from the exhaust gases from the conventional steel furnace. Round-the-clock power and heat from the renewables and Carnot battery (104) may also be supplied to the conventional steel furnace to further reduce the emissions associated with steel production.

[0060] In some embodiments, the carbon dioxide may be provided to the SOEC (106). The SOEC (106), by way of so-electrolysis, may use steam and power from the Carnot battery (104) and carbon dioxide from the steel furnace (124) to directly produce syngas (126). In some other embodiments, the carbon dioxide (124) and the hydrogen from the SOEC (106) may be used to produce syngas (126) by reverse water gas shift or for direct synthesis of electrofuels without syngas as an intermediate step.

[0061] Further, the syngas or green hydrocarbon thus produced may be converted to electrofuels (e-fiiels), for example, methanol using a Fischer-Tropsch synthesis process (128). A person of ordinary skill in the art will understand that the Fischer-Tropsch synthesis process may refer to a collection of chemical reactions that convert the syngas into liquid hydrocarbons. In some other embodiments, the syngas thus produced may be converted to e- fuels using methanol synthesis followed by Methanol-To-Gasoline (MTG) process (130). A person of ordinary skill in the art will understand that the methanol synthesis process may refer to methanol production from the syngas. Further, a person of ordinary skill in the art will understand that the MTG process may refer to a sustainable process for producing gasoline-range hydrocarbon biofuels. In some embodiments, the CO2 produced by scrubbing and hydrogen produced by SOEC (106) may be reacted directly to produce methanol or Fischer-Tropsch fuels without an intermediary step involving syngas (126). A person of ordinary skill in the art will appreciate that other synthesis processes may be implemented within the scope of the present disclosure. Any surplus heat may be recycled to the Carnot battery (104) to further increase the efficiency of the system.

[0062] Many conventional steel plants are relatively new and expected to last decades with emissions locked in. To decarbonize conventional steel (and avoid retiring those plants), the CO2 may be captured from the off gases of the steel plant and used for electrofuels synthesis, as discussed herein. The waste heat of steel production may be recycled to the Carnot Battery (104), as will the process heat of electrofuels synthesis. This recycled heat is important for the complete capture of the substantial CO2 in the exhaust/off gas.

[0063] Therefore, the present disclosure describes an end-to-end solution for steel synthesis with round-the-clock renewable energy using Carnot battery that provides both heat and power to run an SOEC. The heat from the Carnot battery is also used to capture carbon dioxide from exhaust gases of the steel plant or air (DAC arrangement). The processes described herein are for the manufacture of steel, either in greenfield plants or in existing plants that combine conventional steel with green hydrogen production and the CO2 of the former is captured for electro-fuel synthesis.

[0064] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE PRESENT DISCLOSURE

[0065] The present disclosure provides an end-to-end solution for synthesis of steel with green hydrogen regardless of geography.

[0066] The present disclosure utilizes Carnot batteries to eliminate the issue of intermittency of renewables.

[0067] The present disclosure utilizes Carnot batteries that provide both power and heat to run a Solid-Oxide Electrolyser Cell (SOEC) for hydrogen generation with high efficiency as well as power and heat for other processes associated with steel synthesis. [0068] The present disclosure utilizes the power and heat from renewables and Carnot battery to capture CO2 from the exhaust gases of the steel plant and use for electro-fuel synthesis along with green hydrogen.

[0069] The present disclosure utilizes Direct Air Capture (DAC) systems to capture carbon dioxide from the ambient air, which may be reduced to pure carbon and used for carburization in green steel synthesis.

[0070] The present disclosure provides recycling and storing of the process heat released during the downstream processes back to Carnot batteries to increase the total efficiency of the process. [0071] The present disclosure provides SOECs with very high efficiency that can utilize heat and power from Carnot batteries to operate round-the-clock without the need to oversize the electrolysers.

[0072] The present disclosure provides oxygen from SOECs for slag foaming during steel synthesis. [0073] The present disclosure provides a system for decarbonization of existing fossil fuelbased steel plants.

Claims

I Claim:

1. A system (100) for steel synthesis comprising: a Carnot battery (104) configured to receive renewable power supply from one or more intermittent renewable sources (102); a solid-oxide electolyser cell (SOEC) (106) coupled to Carnot battery (104) for producing hydrogen; a direct reduction of iron ore (DRI) reactor (112) configured for reducing the iron ore to a hot reduced iron using hydrogen; and an electric arc furnace (EAF) (116) configured for complete melting of iron and steel synthesis.

2. The system as claimed in claim 1, wherein the Carnot battery (104) stores electricity in the form of thermal energy using processes such as but not limited to thermal energy storage, pumped thermal energy storage, and liquid air energy storage or a combination thereof during the charging cycle.

3. The system as claimed in claim 1, wherein the stored thermal energy is converted back into power (at an efficiency of 60-70%) along with usable heat during the discharge cycle (with the total efficiency of the Carnot Battery >90%), the power and heat are supplied to the SOEC and various other processes in steel synthesis.

4. The system as claimed in claim 1, wherein the oxygen produced by SOEC (106) is fed to the EAF (116) slag foaming.

5. The system as claimed in claim 1, wherein the DRI (112) and EAF (116) produce surplus heat which is recycled to the Carnot battery (104) to be stored and used as dispatchable heat.

6. The system as claimed in claim 1, wherein the carbon is obtained from carbon dioxide captured by DAC (118) using power and heat from renewables (102) and the Carnot battery (104) followed by electrochemical reduction to carbon to be used in the electric arc furnace (116).

7. The system as claimed in claim 2, wherein the system is further applied to a conventional steel furnace using iron ore and coke (124) along with scrubbing of carbon dioxide from offgas.

8. The system as claimed in claim 1 , wherein the CO2 is captured from the EAF off-gas and used for electrofuels synthesis along with green hydrogen or electrochemically reduced to carbon.

9. A method for steel synthesis comprising: a) receiving renewable power supply from one or more intermittent renewable sources

(102) to a Carnot battery (104); b) providing continuous heat and power by Carnot battery (104) to SOEC (106) to produce hydrogen at a high efficiency of more than 90%; c) heating the hydrogen using energy from the renewables (102) and Carnot battery ( 104) to obtain a heated hydrogen (110); d) utilizing the heated hydrogen (110) and iron ore pellets (114) in direct reduction of iron (112) to obtain a hot reduced iron; and e) feeding the hot reduced iron to an electric arc furnace (EAF) (116) with carbon supply for complete melting of iron at high temperature and steel synthesis. 10. The method as claimed in claim 9, wherein the CO2 extraction (118) from the off gas of

EAF for further electroreduction to carbon or use in electrofuels synthesis.