Indonesia

In this study we investigate the effect of the heterogeneous micromechanical stress fields resulting from the grain-scale anisotropy on the redistribution of hydrogen using a diffusion coupled crystal plasticity model. A representative volume element with periodic boundary conditions was used to model a synthetic microstructure. The effect of tensile loading initial hydrogen content and yield strength on the redistribution of lattice (CL) and dislocation trapped (Cx) hydrogen was studied. It was found that the heterogeneous micromechanical stress fields resulted in the accumulation of both populations primarily at the grain boundaries. This shows that in addition to the well-known grain boundary trapping the interplay of the heterogeneous micromechanical hydrostatic stresses and plastic strains contribute to the accumulation of hydrogen at the grain boundaries. Higher yield strength reduced the amount of Cx due to the resulting lower plastic deformation levels. On the other side the resulting higher hydrostatic stresses increased the depletion of CL from the compressive regions and its diffusion toward the tensile ones. These regions with increased CL are expected to be potential damage initiation zones. This aligns with the observations that high-strength steels are more susceptible to hydrogen embrittlement than those with lower-strength.

In the present study hydrogen utilization as diesel engine fuel at low load operation was investigated. Hydrogen cannot be used directly in a diesel engine due to its auto ignition temperature higher than that of diesel fuel. One alternative method is to use hydrogen in enrichment or induction. To investigate the combustion characteristics of this dual fuel engine a single cylinder diesel research engine was converted to utilize hydrogen as fuel. Hydrogen was introduced to the intake manifold using a mixer before entering the combustion chamber. The engine was run at a constant speed of 2000 rpm and 10 Nm load. Hydrogen was introduced at the flow rate of 21.4 36.2 and 49.6 liter/minute. Specific energy consumption indicated efficiency and cylinder pressure were investigated. At this low load the hydrogen enrichment reduced the cylinder peak pressure and the engine efficiency. The reaction progress variable and combustion rate of reaction were slower as shown by the CFD calculation.

The power generation mix of the Association of Southeast Asian Nations (ASEAN) is dominated by fossil fuels which accounted for almost 80% in 2017 and are expected to account for 82% in 2050 if the region does not transition to cleaner energy systems. Solar and wind power are the most abundant energy resources but contribute negligibly to the power mix. Investors in solar or wind farms face high risks from electricity curtailment if surplus electricity is not used. Employing the policy scenario analysis of the energy outlook modelling results this paper examines the potential scalability of renewable hydrogen production from curtailed electricity in scenarios of high share of variable renewable energy in the power generation mix. The study found that ASEAN has high potential in developing renewable hydrogen production from curtailed electricity. The study further found that the falling cost of renewable hydrogen production could be a game changer to upscaling the large-scale hydrogen production in ASEAN through policy support. The results implied a future role of renewable hydrogen in energy transition to decarbonize ASEAN’s emissions.

The potential of electron-donating capability in methoxy groups of antioxidant containing protein (ACAP) as organic catalyst is restricted by its low isoelectric point. The goal of this study is to construct endure ACAP based metal-free organic catalyst for hydrogen production from electrolysis of noodle wastewater. The ACAP was coated thermomechanically on PVC sheet and its performance was tested during electrolysis of noodle wastewater. The morphological analysis phase analysis and elemental analysis of coated materials have shown a simultaneous pattern with electrolysis performances. The use of graphite flake to cover turmeric ACAP obstructs the electron to attack directly the positive charge of ACAP so that the electrocatalytic endurance increases while maintaining the hydrogen production rate. The combination of phenolic and enzymatic ACAPs is found to have the slowest reaction rate and lowest hydrogen production. The phenolic compound inhibits the enzymatic reaction.

Global energy sources are being transformed from hydrocarbon-based energy sources to renewable and carbon-free energy sources such as wind solar and hydrogen. The biggest challenge with hydrogen as a renewable energy carrier is the storage and delivery system’s complexity. Therefore other media such as ammonia for indirect storage are now being considered. Research has shown that at reasonable pressures ammonia is easily contained as a liquid. In this form energy density is approximately half of that of gasoline and ten times more than batteries. Ammonia can provide effective storage of renewable energy through its existing storage and distribution network. In this article we aimed to analyse the previous studies and the current research on the preparation of ammonia as a next-generation renewable energy carrier. The study focuses on technical advances emerging in ammonia synthesis technologies such as photocatalysis electrocatalysis and plasmacatalysis. Ammonia is now also strongly regarded as fuel in the transport industrial and power sectors and is relatively more versatile in reducing CO₂ emissions. Therefore the utilisation of ammonia as a renewable energy carrier plays a significant role in reducing GHG emissions. Finally the simplicity of ammonia processing transport and use makes it an appealing choice for the link between the development of renewable energy and demand.

Growing attention to the environmental aspect has urged the effort to reduce CO2 emission as one of the greenhouse gases. The cement industry is one of the biggest CO2 emitters in this world. Alternative fuel is one of the challenging issues in cement production due to the limited fossil fuel resources and environmental concerns. Meanwhile hydrogen (H2) has been reported as a promising non-carbon fuel with ammonia (NH3) as the main candidate for chemical storage methods. In this work an integrated system of cement production with an alternative H2-based fuel is proposed consisting of the dehydrogenation process of NH3 and the H2 combustion to provide the required thermal energy for clinker production. Different catalysts are employed and evaluated to analyze the specific energy input (SEI). The result shows that the conversion rate strongly determines the SEI with minimum SEI (3829.8 MJ t-clinker-1 ) achieved by Ni-Pt-based catalyst at a reaction temperature of 600 ºC. Compared to the conventional fuel of coal the H2-based integrated cement production system shows a significant decrease of 44% in CO2 emission due to carbon-free combustion using H2 as the fuel. The current study on the proposed integrated system of H2-based cement production also provides an initial thermodynamic analysis and basic observation for the adoption of non-carbon-based H2 including the storage system of NH3 in the cement production process.

Hydrogen has emerged as a pivotal energy carrier in the global transition toward sustainable energy systems. This study analyses current trends sectoral dynamics and future demand projections for hydrogen employing a multi-methodological framework that integrates Compound Annual Growth Rate (CAGR) extrapolation scenario-based modeling and regional comparative analysis. By leveraging historical growth patterns of geothermal bioenergy and wind energy sectors in the European Union (EU) three hydrogen demand scenarios—Conservative (3.25 % CAGR) Moderate (8.33 % CAGR) and Optimistic (15.42 % CAGR)—are projected to 2050. Results indicate that global hydrogen demand could range from 18.8 to 381.3 million tonnes per year by 2050 depending on technological advancements policy frameworks and infrastructure investments. The transportation and industrial sectors are identified as critical drivers while regional disparities highlight leadership from the EU the U.S. and Asia-Pacific nations. The study underscores the necessity of coordinated policy cost reduction in green hydrogen production and infrastructure scalability to realize hydrogen’s potential in decarbonizing energy systems.

Indonesia faces mounting challenges from climate change and environmental degradation underscoring the need for sustainable transportation solutions. This study evaluates factors influencing the adoption of Hybrid Electric Vehicles (HEV) Battery Electric Vehicles (BEV) and Hydrogen Fuel Cell Vehicles (HFCV) using Multi-Criteria Analysis (MCA) and Total Cost of Ownership (TCO) approaches. Eight key factors were analyzed: safety operational and maintenance costs initial cost government incentives charging speed resale value and environmental impact. Findings reveal that safety concerns particularly for hydrogen vehicles rank as the highest priority for consumers followed by cost efficiency and government support. Environmental considerations while significant were lower in priority. The study highlights the importance of targeted subsidies enhanced safety features and infrastructure investments to overcome barriers to adoption. By providing actionable recommendations such as raising public awareness of the long-term benefits of environmentally friendly vehicles this research supports policymakers in driving the transition to sustainable transportation in Indonesia. These insights contribute to addressing rising vehicle emissions and fostering the adoption of HEV5 BEV2 and HFCV6 aligning with Indonesia’s broader climate goals.

Chemical looping hydrogen generation (CLHG) from biomass is a promising technology for producing carbonnegative hydrogen. However achieving autothermal operation without sacrificing hydrogen yield presents a significant thermodynamic challenge. This study proposes and evaluates a novel thermal management strategy that enables a self-sustaining process by balancing the system’s heat load with its internal exothermic reactions. A comprehensive analysis was conducted using process simulation to assess the system’s thermodynamic performance identify key sources of inefficiency through exergy analysis and determine its economic viability via a detailed techno-economic assessment. The results show that a 200 MWth CLHG plant can produce 2.06 t-H2/h with a hydrogen production efficiency and exergy efficiency of 34.46 % and 44.4 % respectively. The exergy analysis identified the fuel reactor as the largest source of thermodynamic inefficiency accounting for 66.4 % of the total exergy destruction. The techno-economic analysis yielded a base-case minimum selling price (MSP) of hydrogen of 2.63 USD/kg a rate competitive with other carbon-capture-enabled hydrogen production methods. Sensitivity analysis confirmed that the MSP is most influenced by biomass price and discount rate. Crucially the system’s carbon-negative nature allows it to leverage carbon pricing schemes which can significantly improve its economic performance. Under the EU’s current carbon price the MSP falls to 0.98 USD/kg-H2 and it can become negative in regions with higher carbon taxes suggesting profitability from carbon credits alone. This study demonstrates that the proposed CLHG system is a technically robust and economically compelling pathway for clean hydrogen production particularly in regulatory environments that incentivize carbon capture.

Installing multi-renewable energy (RE) power plants at designated locations known as RE parks is a promising solution to address their intermittent power. This research focuses on optimizing RE parks for three scenarios: photovoltaic (PV)-only wind-only and hybrid PV-wind with the aim of generating green hydrogen in locations with different RE potentials. To ensure rapid response to RE fluctuations a Proton Exchange Membrane (PEM) electrolyzer is employed. Furthermore this research proposes detailed models for manufacturer-provided wind power curves electrolyzer efficiency against its operating power and electrolyzer cost towards its capacity. Two optimization cases are conducted in MATLAB evaluating the optimum sizes of the plants in minimizing levelized cost of hydrogen (LCOH) using classical discrete combinatorial method and determining the ideal PV-to-wind capacity ratio for operating PEM electrolyzer within hybrid PV-wind parks using particle swarm optimization. Numerical simulations show that wind power-based hydrogen production is more cost-effective than PV-only RE parks. The lowest LCOH $4.26/kg H2 and the highest LCOH $14.378/kg H2 are obtained from wind-only and PV-only configurations respectively. Both occurred in Adum-Kirkeby Denmark as it has highest average wind speed and lowest irradiance level. Notably LCOH is reduced with the hybrid PV-wind configuration. The results suggest the optimum PV-to-wind capacity ratio is 65:35 on average and indicate that LCOH is more sensitive to electrolyzer’s cost than to electricity tariff variation. This study highlights two important factors i.e. selecting the suitable location based on the available RE resources and determining the optimum size ratio between the plants within the RE park.