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Co-optimizing energy and water resources in a microgrid can increase efficiency and improve economic performance. Energy-water storage (EWS) devices are crucial components of a high-efficient energy-water microgrid (EWMG). The state of charge (SoC) at the end of the first day of operation is one of the most significant variables in EWS devices since it is used as a parameter to indicate the starting SoC for the second day which influences the operating cost for the second day. Hence this paper examines the benefits and applicability of a lookahead optimization strategy for an EWMG integrated with multi-type energy conversion technologies and multienergy demand response to supply various energy-water demands related to electric/hydrogen vehicles and commercial/residential buildings with the lowest cost for two consecutive days. In addition a hybrid info-gap/robust optimization technique is applied to cover uncertainties in photovoltaic power and electricity prices as a tri-level optimization framework without generating scenarios and using the probability distribution functions. Duality theory is also used to convert the problem into a single-level MILP so that it can be solved by CPLEX. According to the findings the implemented energy-water storage systems and look-ahead strategy accounted for respectively 4.03% and 0.43% reduction in the total cost.

Natural gas is the most growing fossil fuel due to its environmental advantages. For the economical transportation of natural gas to distant markets physical (i.e. liquefaction and compression) or chemical (i.e. direct and indirect) monetisation options must be considered to reduce volume and meet the demand of different markets. Planning natural gas supply chains is a complex problem in today’s turbulent markets especially considering the uncertainties associated with final market demand and competition with emerging renewable and hydrogen energies. This review study evaluates the latest research on mathematical programming (i.e. MILP and MINLP) as a decisionmaking tool for designing and planning natural gas supply chains under different planning horizons. The first part of this study assesses the status of existing natural gas infrastructures by addressing readily available natural monetisation options quantitative tools for selecting monetisation options and single-state and multistate natural gas supply chain optimisation models. The second part investigates hydrogen as a potential energy carrier for integration with natural gas supply chains carbon capture utilisation and storage technologies. This integration is foreseen to decarbonise systems diversify the product portfolio and fill the gap between current supply chains and the future market need of cleaner energy commodities. Since natural gas markets are turbulent and hydrogen energy has the potential to replace fossil fuels in the future addressing stochastic conditions and demand uncertainty is vital to hedge against risks through designing a responsive supply chain in the project’s early design stages. Hence hydrogen supply chain optimisation studies and the latest works on hydrogen–natural gas supply chain optimisation were reviewed under deterministic and stochastic conditions. Only quantitative mathematical models for supply chain optimisation including linear and nonlinear programming models were considered in this study to evaluate the effectiveness of each proposed approach.

Hydrogen is increasingly recognized as a pivotal energy storage solution and a transformative alternative to conventional energy sources. This review summarizes the evolving landscape of global H2 production and consumption markets focusing on the crucial role of photothermal catalysts (PTCs) in driving Hydrogen evolution reactions (HER) particularly with regards to oxide selenide and telluride-based PTCs. Within this exploration the mechanisms of PTCs take center stage elucidating the intricacies of light absorption localized heating and catalytic activation. Essential optimization parameters ranging from temperature and irradiance to catalyst composition and pH are detailed for their paramount role in enhancing catalytic efficiency. This work comprehensively explores photothermal catalysts (PTCs) for hydrogen production by assessing their synthesis techniques and highlighting the current research gaps particularly in optimizing catalytic stability light absorption and scalability. The energy-efficient nature of oxide selenide and telluride-based PTCs makes them prime candidates for sustainable H2 production when compared to traditional materials. By analyzing a range of materials we summarize key performance metrics including hydrogen evolution rates ranging from 0.47 mmolh− 1 g− 1 for Ti@TiO2 to 22.50 mmolh− 1 g− 1 for Mn0.2Cd0.8S/NiSe2. The review concludes with a strategic roadmap aimed at enhancing PTC performance to meet the growing demand for renewable hydrogen as well as a critical literature review addressing challenges and prospects in deploying PTCs.

This study presents a comprehensive techno-economic assessment (TEA) of alternative hydrogen supply chain (HSC) pathways with a focus on the conditioning transportation and reconditioning stages. The pathways assessed include compressed hydrogen liquefied hydrogen and ammonia as a hydrogen carrier. A distinctive feature of this study is its consideration of a broad range of operational capacities and transportation distances facility economies of scale and multiple vessel capacities. The TEA is complemented by a life cycle assessment (LCA) to incorporate environmental impacts ensuring a holistic analysis of economic and environmental tradeoffs. The results reveal that the compressed hydrogen pathway is optimal for short distances and low-demand scenarios with levelized costs of hydrogen (LCOH) ranging from $1.11/kg to $6.91/kg. Liquefied hydrogen shows economic competitiveness for medium distances with LCOH between $1.43/kg and $3.84/kg. Ammonia emerges as the most cost-effective for longer distances and higher demand levels with LCOH between $1.61/kg and $3.80/kg. However the LCA analysis revealed that the ammonia pathway incurs higher emissions particularly during the ammonia synthesis and cracking processes making it less promising from an integrated perspective. This integration of LCA results into the TEA framework provides a comprehensive view of each pathway accounting for both economic and environmental factors. This study provides a robust framework for guiding decision-makers in the development of an effective hydrogen supply chain integrating both economic and environmental considerations.

This study investigates hydrogen and hydrogen-methane mixtures as alternative fuels for industrial burners focusing on combustion dynamics flame stability and emissions. CFD simulations in ANSYS Fluent utilized the RANS framework with the k-ε turbulence model and the mixture fraction/PDF approach. Supporting Python scripts and Cantera-based kinetic modeling employing the GRI-Mech 3.0 mechanism and Zeldovich pathways analyzed equivalence ratios (Φ) adiabatic flame temperatures (Tad) and NOx formation mechanisms. Results revealed non-linear temperature trends with a 50 % hydrogen blend yielding the lowest peak temperature (1880 K) and a 75 % hydrogen blend achieving optimal performance balancing peak temperatures (~1900 K) reduced NOx emissions (5.39 × 10-6) and near-zero CO2 emissions (0.137) though flame stability was impacted by rich mixtures. Pure hydrogen combustion produced the highest peak temperature (2080 K) and NOx emissions (3.82 × 10-5) highlighting the need for NOx mitigation strategies. Mass flow rate (MFR) adjustments and excess air variation significantly influenced emissions with a 25 % MFR increase reducing NOx to 2.8 × 10-5 while higher excess air (e.g. 30 %) raised NOx under lean conditions. Statistical analysis identified Φ hydrogen content (H2%) and flame stability as key factors with 50 %–75 % hydrogen blends minimizing emissions and optimizing performance emphasizing hydrogen’s potential with controlled MFR and air adjustments.

Green hydrogen (H2 ) a promising clean energy source garnering increasing attention worldwide can be derived through various pathways resulting in differing levels of greenhouse gas emissions. Notably Green H2 production can utilize different methods such as integrating standard photovoltaic panels thermal photovoltaic or concentrated photovoltaic thermal collectors with electrolyzers. Furthermore it can be conditioned to different states or carriers including liquefied H2 compressed H2 ammonia and methanol and stored and transported using various methods. This paper employs the Life Cycle Assessment methodology to compare 18 different green hydrogen pathways and provide recommendations for greening the hydrogen supply chain. The findings indicate that the production pathway utilizing concentrated photovoltaic thermal panels for electricity generation and hydrogen compression in the conditioning and transportation stages exhibits the lowest environmental impact emitting only 2.67 kg of CO2 per kg of H2 .

The increase in the feasibility of hydrogen-based generation makes it a promising addition to the realm of renewable energies that are being employed to address the issue of electric vehicle charging. This paper presents technical and an economical approach to evaluate a newer off-grid hybrid PV-hydrogen energy-based recharging station in the city of Jamshoro Pakistan to meet the everyday charging needs of plug-in electric vehicles. The concept is designed and simulated by employing HOMER software. Hybrid PV-hydrogen and PV-hydrogenbattery are the two different scenarios that are carried out and compared based on their both technical as well as financial standpoints. The simulation results are evident that the hybrid PV- hydrogen-battery energy system has much more financial and economic benefits as compared with the PV-hydrogen energy system. Moreover it is also seen that costs of energy from earlier from hybrid PV-hydrogen-battery is more appealing i.e. 0.358 $/kWh from 0.412 $/kWh cost of energy from hybrid PV-hydrogen. The power produced by the hybrid PV- hydrogen - battery energy for the daily load demand of 1700 kWh /day consists of two powers produced independently by the PV and fuel cells of 87.4 % and 12.6 % respectively.

The integration of renewable resources with advanced storage technologies is critical for sustainable energy systems. In this paper a planning framework for an energy hub incorporating hydrogen and renewable energy systems is developed with the objective of minimizing operational costs while participating in flexible ramping product (FRP) markets. The energy hub is designed to utilize a hybrid storage system comprising multi-type battery energy storage (BESS) accounting for diverse chemistries and degradation behaviors and hydrogen storage (HS) to meet concurrent electric and hydrogen demands. To address uncertainties in renewable generation and market prices a stochastic optimization model is developed to determine the optimal investment capacities while optimizing operational decisions under uncertainty using scenario-based stochastic programming. Financial risks associated with price and renewable variability are mitigated through the Conditional Value-at-Risk (CVaR) metric. Case studies demonstrate that hybrid storage systems including both BESS and HS can reduce total costs by 23.62% compared to single-storage configurations that rely solely on BESS. Based on the results BESS participates more in providing flexible ramp-up services while HS plays a major role in providing flexible ramp-down services. The results emphasize the critical role of co-optimized hydrogen and multi-type BESS in enhancing grid flexibility and economic viability.

Decarbonising aquaculture support vessels is pivotal to reducing greenhouse gas (GHG) emissions across both the aquaculture and maritime sectors. This study evaluates the technical and economic feasibility of deploying hydrogen as a marine fuel for a 14.95 m net cleaning vessel (NCV) operating in Tasmania Australia. The analysis retains the vessel’s original layout and subdivision to enable a like-for-like comparison between conventional diesel and hydrogen-based systems. Two options are evaluated: (i) replacing both the main propulsion engines and auxiliary generator sets with hydrogen-based systems— either proton exchange membrane fuel cells (PEMFCs) or internal combustion engines (ICEs); and (ii) replacing only the diesel generator sets with hydrogen power systems. The assessment covers system sizing onboard hydrogen storage integration operational constraints lifecycle cost and GHG abatement. Option (i) is constrained by the sizes and weights of PEMFC systems and hydrogen-fuelled ICEs rendering full conversion unfeasible within current spatial and technological limits. Option (ii) is technically feasible: sixteen 700 bar cylinders (131.2 kg H2 total) meet one day of onboard power demand for net-cleaning operations with bunkering via swap-and-go skids at the berth. The annualised total cost of ownership for the PEMFC systems is 1.98 times that of diesel generator sets while enabling annual CO2 reductions of 433 t. The findings provide a practical decarbonisation pathway for small- to medium-sized service vessels in niche maritime sectors such as aquaculture while clarifying near-term trade-offs between cost and emissions.