Search Results (1,309)

Accurately determining actual energy consumption is essential for guiding technological developments in the transport sector, assessing vehicle development outcomes, and designing effective energy and climate policies. Although laboratory driving cycles such as the WLTP provide standardized benchmarks, they do not reflect the complex interactions between human behavior, environmental conditions, and vehicle dynamics under real-world operating conditions. This article presents an integrated framework for assessing long-term, actual energy carrier consumption in four main vehicle categories: internal combustion engine vehicles (ICEVs), hybrid electric vehicles (HEVs), hydrogen fuel cell electric vehicles (H2EVs), and battery electric vehicles (BEVs). The entire discussion here is based on the results of data analysis from natural operation using the so-called vehicle energy footprint. This framework provides a method for determining the average energy carrier consumption for each group of vehicles with the specified drivetrains. This information formed the basis for assessing the total energy demand for the operation of the analyzed vehicle types in normal operation. The simulations show that among mid-range passenger vehicles, ICEVs are the most energy-intensive in normal operation, followed by H2EVs and HEVs, and BEVs are the least. This study highlights the methodological challenges and implications of accurately quantifying energy consumption. The presented method for assessing energy demand in vehicle operation can be useful for manufacturers, consumers, fleet operators, and policymakers, particularly in terms of energy efficiency, emission reduction, and public health protection. Full article

Under the dual imperatives of carbon neutrality and marine energy transition, hydrogen has emerged as an emerging energy storage carrier, offering a new pathway for offshore wind power consumption. This study addresses the critical challenges of offshore wind power intermittency and hydrogen transport efficiency bottlenecks by proposing an innovative solution. A coordinated planning method for far-offshore wind–hydrogen systems considering nearshore relay points is developed, establishing a multi-stage optimization framework of “offshore hydrogen production—relay point storage and transportation—hierarchical vessel delivery”. By optimizing hydrogen transport routes through coordinated allocation of electrolyzers, storage tanks, and vessel transportation, and designing a hierarchical transportation model that differentiates between ocean-going and nearshore vessels, the simulation results of a coastal area in China demonstrate that, compared with traditional methods, the proposed approach reduces investment costs and operation costs by nearly 10% while decreasing the monthly wind curtailment rate by 10.53%. Full article

Decarbonisation of the aviation sector is essential for achieving global-climate targets, with hydrogen propulsion emerging as a viable alternative to battery–electric systems for vertical flight. Unlike previous studies focusing on clean-sheet eVTOL concepts or fixed-wing platforms, this work provides a comprehensive retrofit evaluation of a two-seat light helicopter (Cabri G2/Robinson R22 class) to a hydrogen–electric hybrid powertrain built around a Toyota TFCM2-B PEM fuel cell (85 kW net), a 30 kg lithium-ion buffer battery, and 700 bar Type-IV hydrogen storage totalling 5 kg, aligned with the Vertical Flight Society (VFS) mission profile. The mass breakdown, mission energy equations, and segment-wise hydrogen use for a 100 km sortie are documented using a single main rotor with a radius of R = 3.39 m, with power-by-segment calculations taken from the team’s final proposal. Screening-level simulations are used solely for architectural assessment; no experimental validation is performed. Mission analysis indicates a 100 km operational range with only 3.06 kg of hydrogen consumption (39% fuel reserve). The main contribution is a quantified demonstration of a practical retrofit pathway for light rotorcraft, showing approximately 1.8–2.2 times greater range (100 km vs. 45–55 km battery-only baseline, including respective safety reserves). The Hawk demonstrates a 28% reduction in total propulsion system mass (199 kg including PEMFC stack and balance-of-plant 109 kg, H₂ storage 20 kg, battery 30 kg, and motor with gearbox 40 kg) compared to a battery-only configuration (254.5 kg battery pack, plus equivalent 40 kg motor and gearbox), representing approximately 32% system-level mass savings when thermal-management subsystems (15 kg) are included for both configurations. Full article

Atomic Layer Deposition (ALD) is a key thin-film fabrication technique that enables the growth of ultra-thin, conformal, and compositionally controlled layers for applications in nanoelectronics, optoelectronics, and energy devices. However, the high cost and operational complexity of commercial ALD systems limit their accessibility in academic and emerging research environments. In this work, a low-cost, automated thermal ALD system is designed, assembled, and experimentally validated for the deposition of zinc oxide (ZnO) thin films. The developed system enables precise control of precursor dosing, purge sequences, and substrate temperature via an integrated LabVIEW–Arduino control architecture, allowing reproducible and stable thin-film growth. The design allows the use of various precursors through high-precision three-way diaphragm valves. In addition, the system allows continuous purge gas flow in the reaction chamber, which enhances the drag velocity of the precursor gas, reducing dosage requirement, accelerating chamber saturation time and lowering the total consumption of precursors per deposition cycle. ZnO thin films were successfully grown on silicon and glass substrates at 200 °C using diethylzinc (DEZ) as the metal precursor and hydrogen peroxide (H₂O₂) as the oxidant. The process exhibited self-limiting growth characteristics typical of ALD, yielding a growth per cycle of approximately 0.8 Å. The deposited ZnO films exhibited optical transparency of 70–80% in the visible region, a refractive index of approximately 1.9, and an optical bandgap close to 3.4 eV, which are consistent with values reported for high-quality ZnO films grown in commercial ALD systems. These results demonstrate that the proposed low-cost platform is capable of producing functional ZnO thin films with properties comparable to those obtained with conventional commercial reactors. Overall, this work presents an accessible and scalable thermal ALD system that significantly reduces equipment costs while maintaining reliable process control and film quality, offering a practical framework for expanding thin-film research capabilities across microelectronics, optoelectronics, and nanotechnology laboratories. Full article

Cyanobacteria, particularly Microcystis aeruginosa, can form dense blooms that impair water quality, and conventional treatment methods often fail to remove them effectively. This study evaluated the impact of cell age on the performance of the UV/H₂O₂ advanced oxidation process against M. aeruginosa. Cultures of M. aeruginosa were monitored over 64 days at an initial culture density of 1.20 × 10⁶ cells mL⁻¹. For the UV/H₂O₂ experiments, cells were adjusted to a density of 5.00 × 10⁵ cells mL⁻¹, and the growth and oxidative experiments were monitored using parameters such as hydrogen peroxide decay concentration, optical density at 730 nm (OD₇₃₀), cell density, and dissolved organic carbon (DOC). The hydrogen peroxide (H₂O₂) dosages used were 20 mg L⁻¹ and 50 mg L⁻¹, and the results showed that despite varying cell ages, H₂O₂ consumption remained stable at both dosages. While optical density and cell count indicate total cell removal, DOC levels increased due to cell lysis, resulting in contributions from both intracellular and extracellular fractions. A linear correlation was found between cell density and OD₇₃₀, and between total DOC and cell density. In conclusion, cell age did not influence the effectiveness of the UV/H₂O₂ process under the conditions tested. These findings indicate that UV/H₂O₂ can be an effective approach for managing cyanobacterial blooms in water treatment systems, with its performance being unaffected by cell age. Full article

Manganese is a critical raw material and there is currently a great interest in decarbonization in the metallurgical sector for its production. Hydrogen use in manganese and its alloys’ production is in principle possible for sustainable production; however, this requires a technological shift from traditional carbothermic processes to completely new processes; like the HAlMan process. To design a process, it is crucially important to optimize the process conditions (such as temperature) and minimize the quantity of hydrogen gas and the related energy consumptions. In the present work, energy and mass balances for a hydrogen-based reduction reactor were carried out employing thermodynamics software and analytical approaches from room temperatures to 900 °C. It was found that the quantity of hydrogen gas required for the pre-reduction of manganese ore can be significantly reduced via coupling the reduction reactor with a calciner and the hot charge of the calcined ore into the reduction reactor. Moreover, hot H₂-H₂O gas mixture from the reduction reactor outlet can be used for preheating the hydrogen feed of the reactor, and the calcination of the ore, while a portion or all its hydrogen can be recovered and looped. The integrated coupled calcination-reduction process was found to be operated with no external energy supply, or insignificant fuel use. Full article

Chennai’s transport sector is undergoing a structural transition as the city seeks to accommodate rapidly growing travel demand while reducing energy consumption and emissions. This study develops a city-scale system dynamics model using STELLA to simulate long-term transitions in bus and Intermediate Public Transport (IPT) systems over the period 2011–2038. Four policy scenarios—Do Minimum, Partial, Desirable, and Ideal—are evaluated to examine how fleet expansion, propulsion technology substitution, and service restructuring influence urban transport energy sustainability. The model integrates demographic growth, service-level fleet benchmarks, and multiple propulsion pathways, including diesel, CNG, LPG, bio-CNG, hydrogen, and battery- and solar-electric technologies. Full article

The study establishes a comprehensive mathematical modeling framework for solar-driven hydrogen production by integrating a triple-diode photovoltaic (PV) model, an alkaline electrolyzer, and a hydrogen turbine (H₂T), subsequently using hybrid power utilization to optimize hydrogen output. The Triple-Diode Model (TDM) accurately reproduces the electrical performance of a 144-cell photovoltaic module under standard test conditions (STC), enabling precise calculations of hourly maximum power point outputs based on real-world conditions of global horizontal irradiance and ambient temperature. The photovoltaic system produced 1.07 MWh during the summer months (May to September 2025), which was sent straight to the alkaline electrolyzer. The electrolyzer, using Specific Energy Consumption (SEC)-based formulations and Faraday’s law, produced 22.6 kg of green hydrogen and used around 203 L of water. The generated hydrogen was later utilized to power a hydrogen turbine (H₂T), producing 414.6 kWh, which was then integrated with photovoltaic power to create a hybrid renewable energy source. This hybrid design increased hydrogen production to 31.4 kg, indicating a substantial improvement in renewable hydrogen output. All photovoltaic, electrolyzer, and turbine models were integrated into a cohesive MATLAB R2024b framework, allowing for an exhaustive depiction of system dynamics. The findings validate that the amalgamation of H₂T with photovoltaic-driven electrolysis may significantly improve both renewable energy and hydrogen production. This research aligns with Saudi Vision 2030 and global clean-energy initiatives, including the Paris Agreement, to tackle climate change and its negative impacts. An integrated green hydrogen system, informed by this study’s findings, could significantly improve energy sustainability, strengthen production reliability, and augment hydrogen output, fully aligning with economical, technical, and environmental objectives. Full article

Energy management strategies (EMSs) play a critical role in improving both the efficiency and durability of fuel cell electric vehicles (FCEVs). To overcome the limited adaptability and insufficient durability consideration of existing deep reinforcement learning-based EMSs, this study develops a degradation-aware energy management strategy based on the Soft Actor–Critic (SAC) algorithm. By leveraging SAC’s maximum-entropy framework, the proposed method enhances exploration efficiency and avoids premature convergence to operating patterns that are unfavorable to fuel cell durability. A reward function explicitly penalizing hydrogen consumption, power fluctuation, and degradation-related operating behaviors is designed, and the influences of reward weighting and key hyperparameters on learning stability and performance are systematically analyzed. The proposed SAC-based EMS is evaluated against Deep Q-Network (DQN) and Proximal Policy Optimization (PPO) strategies under both training and unseen driving cycles. Simulation results demonstrate that SAC achieves a superior and robust trade-off between hydrogen economy and degradation mitigation, maintaining improved adaptability and durability under varying operating conditions. These findings indicate that integrating degradation awareness with entropy-regularized reinforcement learning provides an effective framework for practical EMS design in FCEVs. Full article

In the context of promoting strategies to mitigate the global warming effect resulting from greenhouse gas emissions produced by human activities, ammonia stands out as an important player in the decarbonization of various sectors, including transportation, energy, and other industries. Ammonia is an effective carrier of hydrogen, having three times the volumetric energy density of hydrogen itself. In this study, the authors present findings obtained from a group of experiments and simulations conducted on a diesel engine operating at a constant speed and under different loads, using a dual-fuel method in which ammonia was injected into the intake manifold to partially replace the original diesel fuel. The results demonstrate that it is possible to reduce fuel consumption and CO₂ emissions. NO_x dropped by 40.8% and soot by 13.4% under heavy load, while under light load, they dropped by 50.5% and 23.3%, respectively. Full article

Nowadays, the automotive industry is primarily driven by the CO₂ policy that targets net zero carbon emissions by 2035 from passenger cars and commercial vehicles. The main path to achieve this goal is the implementation of electric powertrains with the energy stored in batteries, as the case for battery electric vehicles (BEV). However, this technology still faces some difficulties in terms of energy density, overall weight, charging time, and vehicle autonomy. From the other point of view, fuel cell electric vehicles (FCEV) offer the same advantages as BEV in terms of CO₂ reduction, providing better autonomy and lower refueling time. The energy demand by the electric powertrain strongly depends on the vehicle driving conditions as it directly affects energy consumption. In that context, the article aims to study the electrical energy demand of an ultra-energy efficient vehicle intended for a Shell eco-marathon competition in order to minimize hydrogen consumption. The study was carried out over a single lap on the racing track in Nogaro, France while applying the race rules from the competition in 2023. It includes a numerical evaluation of the vehicle resistance forces in different driving strategies and experimental validation on the propulsion test bench. Full article

Hydrogen sulfide (H₂S) prevalent in fuel gases such as natural gas and biogas necessitates removal prior to utilization or pipeline distribution. Biological desulfurization is considered a green purification technology employing sulfur-oxidizing bacteria (SOB) under ambient conditions to eliminate sulfur compounds, offering advantages including high efficiency, simplified equipment, and minimal chemical consumption. A highly efficient SOB TYWJ-2 was isolated in this study. Genomic analysis revealed that strain TYWJ-2 possesses a complete set of sulfur metabolism genes, enabling the metabolism of various inorganic sulfides, along with salt-tolerance genes that support adaptation to high osmolarity environments. The optimal conditions for desulfurization were determined through single-factor experiments and Box–Behnken response surface methodology. Long-term desulfurization performance demonstrated stable operational efficiency, with H₂S removal rates consistently reaching 99.72~99.87%. System performance remained robust under varying sulfur loads, elevated salinity, and intermittent operational shutdowns, with no significant decline in desulfurization efficiency observed. These findings indicate that strain TYWJ-2 holds considerable potential for the biological desulfurization of sulfur-containing biogas and natural gas. Full article

Rapid decarbonization and decentralization of power systems are driving the integration of renewable generation, energy storage and digital technologies into unified energy ecosystems. In this context, photovoltaic (PV) systems combined with battery and hydrogen storage and blockchain-based platforms represent a promising pathway toward sustainable and transparent energy management. This study evaluates the techno-economic performance and operational feasibility of integrated PV systems combining battery and hydrogen storage with a blockchain-based peer-to-peer (P2P) energy trading platform. A simulation framework was developed for two representative consumer profiles: a scientific–educational institution and a residential household. Technical, economic and environmental indicators were assessed for PV systems integrated with battery and hydrogen storage. The results indicate substantial reductions in grid electricity demand and CO₂ emissions for both profiles, with hydrogen integration providing additional peak-load stabilization under current cost constraints. Blockchain functionality was validated through smart contracts and a decentralized application, confirming the feasibility of P2P energy exchange without central intermediaries. Grid electricity consumption is reduced by up to approximately 45–50% for residential users and 35–40% for institutional buildings, accompanied by CO₂ emission reductions of up to 70% and 38%, respectively, while hydrogen integration enables significant peak-load reduction. Overall, the results demonstrate the synergistic potential of integrating PV generation, battery and hydrogen storage and blockchain-based trading to enhance energy independence, reduce emissions and improve system resilience, providing a comprehensive basis for future pilot implementations and market optimization strategies. Full article

It has become an urgent problem to deal with the uncertain influence caused by the high proportion of new energy connected to the grid and improve the consumption level of new energy in the background of the new power system. Based on the constantly updated predicted information of wind power, photovoltaic power, and load power, a multi-time-scale coordinated scheduling model for a multi-energy complementary power generation system integrated with a high proportion of new energy, including an electricity-to-hydrogen system, is proposed. The complex nonlinear factors in the operation cost of thermal power and pumped storage power generation were converted into a mixed integer linear model for solving the problem. The results show that the participation of the pumped storage units in the power grid dispatching can effectively alleviate the peak regulation and reserve pressure of the thermal power units. The electricity-to-hydrogen system has the advantages of fast power response and a wide adjustment range. Pumped storage plant, together with the electricity-to-hydrogen system, enhances the flexible adjustment ability of the power grid on the power side and the load side, respectively. The coordinated dispatch of the two can take into account the safety and economy of the power grid operation, maintain the power balance of the high-proportion new energy power generation system, and effectively reduce green power abandonment and improve the consumption level of clean energy. Full article

Ammonia is considered as a promising hydrogen carrier and a carbon-free fuel. Methods for improving ammonia combustion characteristics often involve its co-firing with more reactive fuels (natural gas, biofuels, etc.). Among the natural gas components, ethane is second most abundant. Therefore, the development of detailed chemical–kinetic mechanisms that accurately consider the interactions between ammonia and each component of natural gas is very important. Such mechanisms must be based on experimental data obtained under a wide range of conditions. In this work, NH₃/C₂H₆/O₂/Ar blends were studied in JSR (φ = 0.5–2.0, p = 1 atm, τ = 1 s, T = 800–1300 K) and in a shock tube (p = 7.3–8.6 atm, T = 1260–1590 K). Additionally, the structure of premixed flames was investigated (φ = 0.8–1.2, p = 1–5 atm). Eleven recently published detailed chemical–kinetic mechanisms were tested. The model Shrestha-2025 was updated to achieve better agreement with the entire set of experimental data. The effect of p and φ on intermediate species concentration was analyzed. Ammonia and ethane consumption pathways were also examined. Full article