Renewable Hydrogen Production Research Articles

CBAM, Hydrogen Partnerships and Egypt’s Industry: Potential for Synergies

Abstract This article examines the hydrogen partnerships between Germany, the EU and Egypt in the context of the EU’s Carbon Border Adjustment Mechanism (CBAM). Germany, the largest future hydrogen importer in the EU, and Egypt, a country with an ambitious hydrogen strategy, are developing a partnership to boost renewable hydrogen production in Egypt. However, high funding costs are a barrier to capital-intensive investments in hydrogen projects, in particular in emerging economies. CBAM provides an incentive to decarbonise but faces resistance in emerging economies as it may undermine the competitiveness of emission-intensive local production. Combining industrial development with hydrogen production could be a more promising partnership strategy than a narrow one focused only on producing hydrogen for export to the EU. By aligning hydrogen partnerships with local development goals, CBAM acceptance can be improved, as industrial development could be climate-friendly, making exports into the EU easier while creating new value chains to the benefit of EU producers.

Nickel phosphide cocatalyst and carbon defects simultaneously boosting the photocatalytic hydrogen production over carbon nitride

The suppression of photogenerated carrier recombination in carbon nitride and the consequent enhancement of its photocatalytic hydrogen evolution performance have emerged as a research hotspot in the field of photocatalysis. Herein, Nickel phosphide (Ni2P) was anchored onto carbon nitride with carbon defects through a synthesis involving thermal polymerization and photoreduction. The existence of carbon defects derived from the rupture of carbon nitride (CN) heterocycles were beneficial to strengthening optical absorption and the separation capabilities of photogenerated carriers. Furthermore, Ni2P cocatalysts could serve as electron acceptors that effectively accelerate the transfer and transport capabilities of the photogenerated charge carriers. Consequently, the 7 wt% Ni2P/CNN photocatalyst achieved a maximum hydrogen evolution rate of 2062 μmol·g−1·h−1, which was 7.8 times and 6.2 times greater than that of Ni2P/CN and Ni/CNN, respectively, and was comparable to the rate achieved by 3 wt% Pt/CNN. This result was comparable or even better than those reported previously. Our work provided a simply strategy for developing non-precious metal-based nickel phosphide photocatalysts for renewable solar-driven photocatalytic hydrogen production.

Aqueous Phase Reforming of Dairy Wastewater for Hydrogen Production: An Experimental and Energetic Assessment

The treatment of dairy industry effluents poses a significant challenge from the environmental point of view because of its high organic load. In this work, the aqueous phase reforming of lactose was investigated as a representative model compound for the production of renewable hydrogen. The tests were conducted using two different scenarios: the first one is referred to as direct aqueous phase reforming (APR); the second one proposed a pre-hydrogenation step, followed by APR. The implementation of this reactive pretreatment allowed for minimizing the solid by-product formation with respect to the direct APR, where most of the initial carbon ended up as solid residue. The pre-hydrogenation was investigated in the range of 180–220 °C, using Ru-based catalysts. In the best scenario (using 5% Ru/C), the carbon to solid was reduced by 95%, and up to 70% of the initial carbon was converted into gaseous compounds, hence contributing to the removal of the organic content of the wastewater while producing an energy carrier. Moreover, the hydrogen selectivity increased up to 70% (with respect to 2.5% for direct APR), thanks to hindering homogeneous reaction pathways that do not lead to hydrogen production. Finally, an energetic analysis was conducted to assess the possibility of coupling the APR with the dairy industry and quantifying the percentage of energy which may be produced in situ to satisfy industrial duties.

Ultrafine CoRu alloy nanoclusters densely anchored on Nitrogen-Doped graphene nanotubes for a highly efficient hydrogen evolution reaction

Designing highly efficient and stable electrocatalysts for hydrogen evolution reactions (HER) is essential to the production of green and renewable hydrogen. Metal-organic framework (MOF) precursor strategies are promising for the design of excellent electrocatalysts because of their porous architectures and adjustable compositions. In this study, a hydrogen-bonded organic framework (HOF) nanowire was developed as a precursor and template for the controllable and scalable synthesis of CoRu-MOF nanotubes. After calcination in Ar, the CoRu-MOF nanotubes were converted into N-doped graphene (NG) nanotubes with ultrafine CoRu nanoclusters (hereon called Co-xRu@NG-T; x = 0, 5, 10, 15, 25 representing the Ru content of 0–0.25 mmol; T = 400 °C to 700 °C) that were densely encapsulated and isolated on the shell. Taking advantage of the synergistic effects of the porous, one-dimensional hollow structure and ultrafine CoRu nanoclusters, the optimized Co-15Ru@NG-500 catalyst demonstrated superior catalytic performance for HERs in alkaline electrolytes with an overpotential of only 30 mV at 10 mA cm−2 and robust durability for 2000 cycles, which outperforms many typical catalytic materials, such as commercial Pt/C. This work introduces a novel high-efficiency and cost-effective HER catalyst for application in commercial water-splitting electrolysis.

Parametric Study and Optimization of Hydrogen Production Systems Based on Solar/Wind Hybrid Renewable Energies: A Case Study in Kuqa, China

Based on the concept of sustainable development, to promote the development and application of renewable energy and enhance the capacity of renewable energy consumption, this paper studies the design and optimization of renewable energy hydrogen production systems. For this paper, six different scenarios for grid-connected and off-grid renewable energy hydrogen production systems were designed and analyzed economically and technically, and the optimal grid-connected and off-grid systems were selected. Subsequently, the optimal system solution was optimized by analyzing the impact of the load data and component capacity on the grid dependency of the grid-connected hydrogen production system and the excess power rate of the off-grid hydrogen production system. Based on the simulation results, the most matched load data and component capacity of different systems after optimization were determined. The grid-supplied power of the optimized grid-connected hydrogen production system decreased by 3347 kWh, and the excess power rate of the off-grid hydrogen production system decreased from 38.6% to 10.3%, resulting in a significant improvement in the technical and economic performance of the system.

Efficient Acidic Photoelectrochemical Water Splitting Enabled by Ru Single Atoms Anchored on Hematite Photoanodes.

Photoelectrochemical (PEC) water splitting in acidic media holds promise as an efficient approach to renewable hydrogen production. However, the development of highly active and stable photoanodes under acidic conditions remains a significant challenge. Herein, we demonstrate the remarkable water oxidation performance of Ru single atom decorated hematite (Fe2O3) photoanodes, resulting in a high photocurrent of 1.42 mA cm-2 at 1.23 VRHE under acidic conditions. Comprehensive experimental and theoretical investigations shed light on the mechanisms underlying the superior activity of the Ru-decorated photoanode. The presence of single Ru atoms enhances the separation and transfer of photogenerated carriers, facilitating efficient water oxidation kinetics on the Fe2O3 surface. This is achieved by creating additional energy levels within the Fe2O3 bandgap and optimizing the free adsorption energy of intermediates. These modifications effectively lower the energy barrier of the rate-determining step for water splitting, thereby promoting efficient PEC hydrogen production.

The industry transformation from fossil fuels to hydrogen will reorganize value chains: Big picture and case studies for Germany

In many industries, low-carbon hydrogen will substitute fossil fuels in the course of the transformation to climate neutrality. This paper contributes to understanding this transformation. This paper provides an overview of energy- and emission-intensive industry sectors with great potential to defossilize their production processes with hydrogen. An assessment of future hydrogen demand for various defossilization strategies in Germany that rely on hydrogen as a feedstock or as an energy carrier to a different extent in the sectors steel, chemicals, cement, lime, glass, as well as pulp and paper is carried out. Results indicate that aggregate industrial hydrogen demand in those industries would range between 197 TWh and 298 TWh if production did not relocate abroad for any industry sector. The range for hydrogen demand is mainly due to differences in the extent of hydrogen utilization as compared to alternative transformation paths for example based on electrification. The attractiveness of production abroad is then assessed based on the prospective comparative cost advantage of relocating parts of the value chain to excellent production sites for low-carbon hydrogen. Case studies are provided for the steel industry, as well as the chemical industry with ethylene production through methanol and the production of urea on the basis of ammonia. The energy cost of the respective value chains in Germany is then compared to the case of value chains partly located in regions with excellent conditions for renewable energies and hydrogen production. The results illustrate, that at least for some processes – as ammonia production – relocation to those favorable regions may occur due to substantial comparative cost advantages.

Numerical study on a novel solar-thermal-reaction system for clean hydrogen production of methanol-steam reforming

Renewable energy-driven hydrogen production methods offer a promising solution for mitigating energy crises. The present study introduces a new solar-driven hydrogen production system that within methanol steam reforming (MSR) process. The numerical analysis is carried out using a cylindrical Fresnel linear concentrator coupled with a solar thermal reactor (STR). A comprehensive kinetic model of the MSR reaction was constructed and combined with analytical methods based on Monte Carlo ray tracing methods and finite volume methods to analyze the multi-physical properties involved in the reaction process. The results indicate that a novel solar-driven MSR-STR system can generate a sufficient driving force after adjusting the concentrator structure and relative position to match the energy demand of the MSR reaction. The accuracy of the model is compared with the experimental values, and the average error is 7.8 %. Tracking error of the component should be maintained below 1.5° to ensure the optical efficiency. The annual hydrogen production was analyzed and the levelized cost of hydrogen is $1.77/kg. Finally, a comparison is presented between the proposed MSR-STR system and parabolic trough concentrator based MSR hydrogen production system to evaluate the feasibility of the former in terms of the economics of implementation.

Towards energy freedom: Exploring sustainable solutions for energy independence and self-sufficiency using integrated renewable energy-driven hydrogen system

In the pursuit of sustainable energy solutions, the integration of renewable energy sources and hydrogen technologies has emerged as a promising avenue. This paper introduces the Integrated Renewable Energy-Driven Hydrogen System as a holistic approach to achieve energy independence and self-sufficiency. Seamlessly integrating renewable energy sources, hydrogen production, storage, and utilization, this system enables diverse applications across various sectors. By harnessing solar and/or wind energy, the Integrated Renewable Energy-Driven Hydrogen System optimizes energy generation, distribution, and storage. Employing a systematic methodology, the paper thoroughly examines the advantages of this integrated system over other alternatives, emphasizing its zero greenhouse gas emissions, versatility, energy resilience, and potential for large-scale hydrogen production. Thus, the proposed system sets our study apart, offering a distinct and efficient alternative compared to conventional approaches. Recent advancements and challenges in hydrogen energy are also discussed, highlighting increasing public awareness and technological progress. Findings reveal a payback period ranging from 2.8 to 6.7 years, depending on the renewable energy configuration, emphasizing the economic attractiveness and potential return on investment. This research significantly contributes to the ongoing discourse on renewable energy integration and underscores the viability of the Integrated Renewable Energy-Driven Hydrogen System as a transformative solution for achieving energy independence. The employed model is innovative and transferable to other contexts.

Racing for Green Hydrogen Economics with Polymer Electrolyte Water Electrolysis – How to Be Achieved

AbstractFor renewable hydrogen production, polymer electrolyte membrane water electrolysis is the most promising technology. However, the technology is not yet competitive with conventional hydrogen production in terms of cost. The impact of cost reduction options on CAPEX and OPEX is investigated. Depending on the hours of operation, the main cost factor is the production and manufacturing of components or the price of electricity. Clearly a tremendous need to implement low‐cost electrolysis cells on a large scale to bring green hydrogen production costs to a level 1–3 € kg−1 hydrogen.

Integration of Power to X Economy in Existing Energy System – Case Finland

Hydrogen or Power-to-X economy is seen as the most promising way to carry out the energy transition from fossil to renewable carbon free energy system. Electrification of the society and green hydrogen-based energy system require huge capacity increase in renewable energy production and energy transmission. This paper introduces a simulation study about the integration of green hydrogen-based energy system to existing power system structure in Finland. Regional energy balances are studied with different options of locations of renewable energy and hydrogen production plants and needs for energy transportation either as electricity or hydrogen. The model includes sectoral couplings between electricity, hydrogen and heating grids and finds synergies of flexibility between different energy grids.

Voltage control method for multi-energy system based on the coupling of renewable energy hydrogen production and storage

Renewable energy power generation combined with hydrogen storage, is an important way to realize the deep integration of hydrogen energy and renewable energy in multi-energy systems. In the multi-energy system of renewable energy power generation and hydrogen production in AC/DC hybrid. Due to the fluctuation of heat load and electric hydrogen production load in the system and the multi-time scale characteristics of energy flow transmission of heat storage and hydrogen storage. It will lead to the difficulty of power coordination in the whole Multi Energy System (MES). In order to solve the problem of power imbalance in MES, this paper first establishes the hybrid power flow equation of MES cluster composed of AC/DC and hydrogen energy transmission channels. The reactive voltage fluctuation characteristics of the AC/DC system under the fluctuation of energy exchange, system energy conversion, and renewable energy output of the MES cluster interconnection channel are analyzed. Secondly, a multi-energy flow model of the multi-energy system is established. The main factors affecting the voltage-reactive power of the AC system are analyzed. A reactive power model based on electro-thermal conversion, hydrogen storage, and multi-energy transmission channels is established. Then, a generation algorithm of the safe and stable boundary of pipeline pressure is proposed to maintain the pressure of hydrogen production and storage system within a safe range. The robust optimization control method is used to control the coupling of multi-energy sources. Finally, based on the actual operation data of the multi-energy power system. The simulation model of reactive power dynamic optimization control for multi-energy interconnected systems is established. The simulation results show that the control method proposed in this paper is adopted. Through the coordinated distribution of energy among multi-energy systems, the voltage stability level of the system can be effectively improved.

Facile fabrication of binary copper–palladium alloy thin film catalysts for exceptional hydrogen evolution performance

The hydrogen evolution reaction (HER) plays a crucial role in realizing the ambitious objectives of renewable hydrogen (H2) production and CO2 neutrality.

Impacts of EU Regulation on Green Hydrogen Production and Storage Capacity Design and Operation

In European Union green hydrogen production is regulated to guarantee that transition to green energy will really have positive effect on the mitigation of the climate change, and that the integration of hydrogen economy to existing energy system will be as smooth as possible. However, these regulations complicate the optimal design and operation of the hydrogen production. Requirement about one-hour temporal correlation between contracted variable renewable electricity production and green hydrogen production forces to invest in overcapacity of electrolyzers and high-capacity hydrogen storages to buffer variable hydrogen production to smooth supply flow to hydrogen end use processes. This paper explains these issues with a demonstrative example how different design parameters result to the operation performance of the hydrogen production process.

Fabrication of novel mixed matrix polymer electrolyte membranes (PEMs) intended for renewable hydrogen production via electrolysis application

Hydrogen gas is among the sustainable energy forms that counteract the energy crisis.

Decentralized Energy Management of Renewable Hydrogen Production Systems Without Communication Networks

Decentralized Energy Management of Renewable Hydrogen Production Systems Without Communication Networks

Z-scheme charge transfer between a conjugated polymer and α-Fe2O3 for simultaneous photocatalytic H2 evolution and ofloxacin degradation

A Z-scheme pathway of the polymer/Fe2O3 heterojunction is revealed based on work function regulation for simultaneous photocatalytic H2 evolution and ofloxacin degradation.

Economics of renewable hydrogen production using wind and solar energy: A case study for Queensland, Australia

This study presents a technoeconomic analysis of renewables-based hydrogen production in Queensland, Australia under Optimistic, Reference and Pessimistic scenarios to address uncertainty in cost predictions. The goal of the work was to ascertain if the target fam-gate cost of AUD 3/kg (approx. USD 2/kg) could be reached. Economies of scale and the learning rate concept were factored into the economic model to account for the effect of scale-up and cost reductions as electrolyser manufacturing capacity grows. The model assumes that small-scale to large-scale wind turbine (WT)-based and photovoltaic (PV)-based power generation plants are directly coupled with an electrolyser array and utilises hourly generation data for the Gladstone hydrogen-hub region. Employing first a commonly used simplified approach, the electrolyser array was sized based on the maximum hourly power available for hydrogen production. The initial results indicated that scale-up is very beneficial: the levelised cost of green hydrogen (LCOH) could decrease by 49% from $6.1/kg to $3.1/kg when scaling PV-based plant from 10 MW to 1 GW, and for WT-based plant by 36% from $5.8/kg to $3.7/kg. Then, impacts on the LCOH of incorporating curtailment of ineffective peak power and electrolyser overload capacity were investigated and shown to be significant. Also significant was the beneficial effect of recognising that electrolyser efficiency depends on input power. The latter two factors have mostly been overlooked in the literature. Incorporating in the model the influence on the LCOH of real-world electrolyser operational characteristics overcomes a shortcoming of the simplified sizing method, namely that a large portion of electrolyser capacity is under-utilised, leading to unnecessarily high values of the LCOH. It was found that AUD 3/kg is achievable if the electrolyser array is properly sized, which should help to incentivise large-scale renewable hydrogen projects in Australia and elsewhere.

Sea urchin-like nitrogen doped hierarchically carbon materials derived from bimetallic-MOF for fast and efficient hydrogen production of formic acid

Formic acid (FA) exists in chemical industrial waste water and has practical potential for renewable hydrogen production by FA dehydrogenation (FAD) for application in fuel cells. In this work, we employed a bimetallic-based MOF Al/Co-BTC (1,3, 5-trimeric acid) as precursor to fabricate a sea urchin-like spherical nitrogen-doped superstructure (V-NCR) with carbon nanorods (CNRs). The carbon material was activated in hot NaOH solution and then loaded with Pd nanoparticles for FAD. As a result, Pd@V-NCRB-800 exhibits a remarkable catalytic activity: the turnover frequency (TOF) value up to 20578 h−1 at 333 K with the 100 % H2 selectivity and excellent cyclic stability, which attributes to the numerous chemical contact sites provided by carbon materials, CNRs, and the modifying electronic interaction of N and Co species.

Cobalt–organic framework as a Bi–functional electrocatalyst for renewable hydrogen production by electrochemical water splitting

Sustainable hydrogen production by electrocatalytic water splitting is an attractive approach to establish a carbon–free future. On the other hand, the operationalization of this technology on a large scale requires the design and synthesis of efficient electrocatalysts to promote hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Metal–organic frameworks (MOFs) have provided new opportunities in the field of electrocatalytic water splitting due to their unique properties. Herein, we report an affordable, simple, and environmentally friendly strategy for the synthesis of Co3(BTC)2 MOF electrocatalyst in distilled water at room temperature. Surprisingly, Co3(BTC)2 demonstrated superior electrocatalytic activity toward HER and OER in alkaline media. The Co3(BTC)2 requires overpotentials of 450 and 370mV for HER and OER to achieve a current density of 10mA cm−2, respectively.