Iran, Islamic Republic of

The urgent need for low carbon emissions in hydrogen production has become increasingly critical as global energy demands rise highlighting the inefficiencies in traditional methods and the industry’s challenges in meeting evolving environmental standards. This review aims to provide a comprehensive overview of these challenges and opportunities. The current review discusses the use of artificial intelligence (AI) technologies especially machine learning (ML) and deep learning (DL) algorithms for process optimization in hydrogen production and associated power systems. The current study analyzes data from several important industry case studies and recently published studied evidence by using a review methodology in order to critically evaluate the effectiveness of AI applications. Key findings show how AI greatly improves operational efficiency through optimized production conditions and forecasted energy use. The review indicates that real-time data processing by AI helps to quickly detect anomalies for timely correction minimizing downtimes and maximizing reliability. Integrating AI with energy management solutions not only optimizes hydrogen production but also supports a transition to sustainable energy systems. Thus the current review recommends strategic investments in AI technologies and comprehensive training programs to harness their full potential ultimately contributing to a more sustainable energy future.

Green hydrogen is a promising solution within carbon free energy systems with Sub-Saharan Africa being a possibly well-suited candidate for its production. However green hydrogen production in Sub-Saharan Africa is not yet investigated in detail. This work determines the cost-potential for green hydrogen production within this region. Therefore a potential analysis for PV wind and hydropower groundwater analysis and energy systems optimization are conducted. The results are evaluated under local socio-economic factors. Results show that hydrogen costs start at 1.6 EUR/kg in Mauritania with a total potential of ~259 TWh/a under 2 EUR/kg in 2050. Two third of the region experience groundwater limitations and need desalination at an added costs of ~1% of hydrogen costs. Socio-economic analysis show that green hydrogen deployment can be hindered along the Upper Guinea Coast and the African Great Lakes driven by limited energy access low labor costs in West Africa and high labor potential in other regions.

An increasing demand for energy coupled with rising pollution levels is driving the search for environmentally clean alternative energy resources to replace fossil fuels. Hydrogen has emerged as a promising clean energy carrier and raw material for various applications. However its environmental benefits depend on sustainable production methods. The rapid development of nanomaterials (NMs) has opened new avenues for the conversion and utilization of renewable energy (RE). NMs are becoming increasingly important in addressing challenges related to hydrogen (H₂) generation. This review provides an overview of current advancements in H₂ production from biomass via thermochemical (TC) and biological (BL) processes including associated costs and explores the applications of nanomaterials in these methods. Research indicates that biological hydrogen (BL-H₂) production remains costly. The challenges associated with the TC conversion process are examined along with potential strategies for improvement. Finally the technical and economic obstacles that must be overcome before hydrogen can be widely adopted as a fuel are discussed.

This article discusses the planning sizing and placement of a vehicle refueling station supplied by renewable energy systems including photovoltaic wind biomass units and an integrated battery system within a smart distribution network. The proposed station comprises facilities for hydrogen fueling and electric vehicle charging stations structured as a bi-level optimization approach. The upper-level model focuses on the planning phase of the refueling station. Its objective is to minimize annual costs associated with construction maintenance and operation. Key constraints involve operational planning for renewable sources battery systems and vehicle refueling stations while accounting for reactive power management. In contrast the lower-level formulation deals with the eco-scheduling of smart distribution grid. Its goal is to minimize the sum of annual energy losses and operation costs within the grid governed by linearized optimal power flow model. To account for uncertainties in demand energy prices renewable generation output and refueling station performance a stochastic optimization framework is employed. The solution is derived using Benders decomposition algorithm to achieve optimal results. The primary innovation highlighted in this paper includes integrating renewable resources and battery systems to power the refueling station leveraging reactive power control for improved station performance and addressing both operational and economic objectives in the distribution system. Numerical results underscore the advantages of this strategy. Constructing a refueling station without battery and renewable units leads to significant drawbacks an increase in network operation cost by 144.6% and grid energy loss by 167.6%. Voltage levels drop below 0.9 per-unit and distribution lines experience severe loading of up to 34.7%. In contrast the proposed plan enhances network economics by 51.3%-74.5% and operational conditions by 17.7%-148.1% effectively showcasing the benefits of incorporating sustainable technologies and advanced planning methods into refueling station development.

The energy hub (EH) concept is an efficient way to integrate various energy carriers. Inaddition demand response programmes (DRPs) are complementary to improving anEH's efficiency and increase energy system flexibility. The hydrogen storage system as agreen energy carrier has an essential role in balancing supply and demand preciselysimilar to other storage systems. A hybrid robust‐stochastic approach is applied herein toaddress fluctuations in wind power generation multiple demands and electricity marketprice in a hydrogen‐based smart micro‐energy hub (SMEH) with multi‐energy storagesystems. The proposed hybrid approach enables the operator to manage the existinguncertainties with more flexibility. Also flexible electrical and thermal demands under anintegrated demand response programme (IDRP) are implemented in the proposedSMEH. The optimal scheduling of the hydrogen‐based SMEH problem considering windpower generation and electricity market price fluctuations as well as IDRP is modelledvia a mixed‐integer linear programming problem. Finally the validity and applicability ofthe proposed model are verified through simulation and numerical results.

The perspective of natural hydrogen as a clear carbon-free and renewable energy source appears very promising. There have been many studies reporting significant concentrations of natural hydrogen in different countries. However natural hydrogen is being extracted to generate electricity only in Mali. This issue originates from the fact that global attention has not been dedicated yet to the progression and promotion of the natural hydrogen field. Therefore being in the beginning stage natural hydrogen science needs further investigation especially in exploration techniques and exploitation technologies. The main incentive of this work is to analyze the latest advances and challenges pertinent to the natural hydrogen industry. The focus is on elaborating geological origins ground exposure types extraction techniques previous detections of natural hydrogen exploration methods and underground hydrogen storage (UHS). Thus the research strives to shed light on the current status of the natural hydrogen field chiefly from the geoscience perspective. The data collated in this review can be used as a useful reference for the scientists engineers and policymakers involved in this emerging renewable energy source.

The main aim of this study deals with the potential evaluation of a fluidized bed membrane reactor (FBMR) for hydrogen production as a clean fuel carrier via methanol steam reforming reaction comparing its performance with other reactors including packed bed membrane reactors (PBMR) fluidized bed reactors (FBR) and packed bed reactors (PBR). For this purpose a two-dimensional axisymmetric numerical model was developed using computational fluid dynamics (CFD) to simulate the reactor performances. Model accuracy was validated by comparing the simulation results for PBMR and PB with experimental data showing an accurate agreement within them. The model was then employed to examine the effects of key operating parameters including reaction temperature pressure steam-to-methanol molar ratio and gas volumetric space velocity on reactor performance in terms of methanol conversion hydrogen yield hydrogen recovery and selectivity. At 573 K 1 bar a feed molar ratio of 3/1 and a space velocity of 9000 h−1 the PBMR reached the best results in terms of methanol conversion hydrogen yield hydrogen recovery and hydrogen selectivity such as 67.6% 69.5% 14.9% and 97.1% respectively. On the other hand the FBMR demonstrated superior performance with respect to the latter reaching a methanol conversion of 98.3% hydrogen yield of 95.8% hydrogen recovery of 74.5% and hydrogen selectivity of 97.4%. These findings indicate that the FBMR offers significantly better performance than the other reactor types studied in this work making it a highly efficient method for hydrogen production through methanol steam reforming and a promising pathway for clean energy generation.

Hydrogen production has recently attracted much attention as an energy carrier and sector integrator (i.e. electricity and transport) in future decarbonized smart energy systems. At the same time power production is highly valued in energy systems as other sectors like transport and heating become electrified. This work compares two different low-emission systems to produce electricity hydrogen and heat. The proposed systems are based on chemical looping combustion combined with biomass gasification (CLC-BG) and steam methane reforming (CLC-SMR) both benefiting from heat integration between chemical looping combustion and downstream processes. A full process simulation is carried out in Aspen Plus for both systems and detailed modeling is performed for chemical looping combustion. The overall thermal efficiency is calculated to be 71.1 % for CLC-BG and 76.4 % for CLC-SMR. Co-feeding methane into the biomass gasification process of CLC-BG leads to an enhanced overall efficiency. In comparison to CLC-BG CLC-SMR exhibits greater potential in terms of power and hydrogen generation resulting in a higher exergy efficiency of 58.3 % as opposed to 44.6 %. Assuming market prices of 5.2 USD/GJ for biomass and 9.1 USD/GJ for natural gas the lowest minimum hydrogen sale price is estimated to be 4 USD/kg for CLC-SMR.

This study presents a simulation and analysis of a shrouded wind turbine system integrated with a proton exchange membrane electrolyzer (PEME) for hydrogen production. The novel aspect of this research lies in the use of an aerodynamic blade shroud to enhance the wind turbine's performance particularly at low wind speeds. The addition of the aerodynamic shroud increases the power output by up to 68% at a wind speed of 2.5 m/s compared to a conventional wind turbine. Additionally the effect of radial clearance between the shroud and turbine blades is explored showing that a smaller clearance significantly improves power generation. The study also investigates the impact of blade shape (NACA 2408 and NACA 4418) on performance with results indicating a 53% increase in power output for the NACA 4418 design compared to the unshrouded turbine. The influence of the aerodynamic blade shroud on PEME energy density and hydrogen production efficiency is discussed demonstrating how increasing wind turbine power output leads to higher current density in the electrolyzer which while increasing hydrogen production slightly reduces thermal and exergy efficiencies. To counteract this the study suggests using multiple PEME stacks in parallel to enhance both efficiency and hydrogen output.

The significant growth of both the global population and economy in recent years has led to a rise in global energy demand. Fossil fuels have a significant contribution to generating energy which has raised concerns about sustainability and environmental impact. There are widespread efforts to find alternative sources in order to reduce dependence on fossil fuels and mitigate their environmental consequences. Among the alternative sources hydrogen has emerged as a promising option due to its potential to be a clean and sustainable energy source. Hydrogen possesses several advantages such as a high calorific value a high reaction rate various sources and the ability to integrate with other renewable energy sources and existing systems. These attributes render hydrogen a stable and reliable energy resource which can help reduce greenhouse gas emissions (GHG) and transition towards a sustainable future. In this review paper distinct hydrogen production technologies such as conventional renewable and nuclear energy are investigated and compared. In addition the challenges and limitations of the application of hydrogen fuel cells on vehicles and hydrogen circulation components are explored. Finally the environmental impact of hydrogen vehicles specifically their role in promoting sustainable development is investigated.