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In the context of current global debates about assuring sustainability of human society renewable energy resources have started to find a main role regarding assuring needed energy supply on different levels. In the last time it has been noticed that Artificial Intelligence, AI is transforming the renewable energy sector by optimizing the usage of energy resources like wind, solar, and hydro, which are per-se not constantly available. By applying AI in connection to using renewable energy resources, improving odds...

Accurate flow measurement is an essential aspect of industrial process monitoring, laboratory experimentation, and modern energy systems. Differential pressure flowmeters, particularly orifice-based devices, remain widely used due to their simplicity, robustness, and standardized measurement principles. However, conventional manufacturing of such components typically requires precision machining, which can increase production costs and reduce flexibility during prototyping and design optimization. This study prese...

In the context of the transition to a hydrogen-based economy, the assessment of the risks associated with this energy vector is becoming a priority for industrial safety. The unique properties of hydrogen, its high reactivity and high burning rate, require the use of advanced numerical simulation tools, capable of providing highly accurate predictions of the effects of explosive phenomena. This paper presents methodological contributions aimed at optimizing the numerical models used for the analysis of explosions ...

The main aim of this paper is to present the research findings in the field of solid biofuels production from biomass. One of the recovery possibilities for waste biomass raw materials is production of solid biofuels. Using a variety combination of influencing variables can be improve the final quality of solid biofuels. Raw biomass material variables influence, especially (type of raw material, particle size, moisture content, compression pressure and compression temperature) can be recognized during the producti...

This paper presents the design and numerical analysis of an experimental system intended to study the effects of water curtains on the propagation of hydrogen explosions. The developed virtual model reproduces a test stand consisting of three successive chambers separated by two water-filled barriers acting as water curtain obstacles. The atmosphere in the chambers is composed of an explosive hydrogen–air mixture with a hydrogen concentration of 25%. The explosion is initiated in the first chamber, and the propa...

Nowadays the communication is made mainly through electronic devices. These devices produce electromagnetic radiation that influences the quality of the sent signal. Also, health problems are generated due to the time spent in an electromagnetic medium that emits radiations. This paper presents some of latest screen developments regarding electromagnetic screens, advancements in shielding materials.

Making an oxygen steel factory (Basic Oxygen Furnace - BOF) more efficient focuses on maximizing energy recovery, optimizing the oxygen blow process, reducing fossil fuel reliance, and enhancing material recycling. Modern advancements allow for significant reductions in carbon footprint and operational costs. The BOF is highly energy-efficient in terms of process heat, consuming only about 1.2 GJ per tonne of crude steel, as it relies on the exothermic oxidation of impurities in hot metal. While the overall BF-BOF...

This paper proposes an engineering framework for the integration of wind energy conversion systems on maritime vessels, with application to navigation conditions specific to the maritime sector of Danube. The study addresses the growing need for practical decarbonization solutions by exploring the technical and operational requirements for implementing small-scale wind energy technologies onboard. The framework combines system design criteria, installation constraints, and performance assessment methodologies to s...

Thermoelectricity is a green, renewable energy technology that uses the Seebeck effect to convert waste heat directly into electricity. Cobaltites have great potential for use in thermoelectric generators due to their environmental friendliness, good thermal and chemical stability, and relatively low raw-material costs. Improving the thermoelectric performance of cobaltites using suitable dopants could expand their application potential. This study investigated the effect of bismuth oxide (Bi2O3) and bismuth borat...

As is well known, hydrogen exhibits a wide flammability range, low ignition energy, and high diffusivity, which create significant explosion risks in storage and handling facilities. Therefore, the development of effective methods and devices for the detection and control of hydrogen explosions is essential to ensure operational safety. This paper presents the development and experimental validation of an explosion control device intended for hydrogen storage systems. The proposed device is based on an optical ult...

Lignin is a heterogeneous phenolic polymer that gives rigidity to plant cell walls and accounts for 15-40% of the dry weight of biomass [1]. Natural lignocellulosic materials have low solubility and processability, which limits their effective practical application [2]. Modern research on lignin processing focuses on depolymerization processes followed by conversion of the resulting monomers either by hydroprocessing or oxidation. Oxidative conversion of lignin is carried out using biotechnological methods (enzyme...

Renewable energy has a vital role in reducing greenhouse gas emissions and other forms of pollution, as well as in increasing a countrys security of energy supply. A 20% share of renewables could mean avoiding 600-900 MtCO2 (million tonnes of CO2) per year. Renewable energy can be used in the electricity generation, heating and cooling, and transport sectors. The purpose of this study is to analyze the trends in the field of renewable energies in the Republic of Moldova. Introduction Agriculture remains a strategi...

Selective hydrogenation of biomass-derived molecules catalyzed by metals is in high demand, but is challenging due to complex reaction pathways. Furfural (FF) is a highly effective chemical produced by processing agricultural and woodworking waste and used to produce furfuryl alcohol (FA), furan, 2-methylfuran, tetrahydrofurfuryl alcohol, etc. Furfuryl alcohol is used in the production of acid-resistant polymer concrete, fiberglass, paint and varnish materials (as a film-forming agent), as well as to create variou...

This study presents the onboard integration and experimental evaluation of a small-scale wind turbine installed on a maritime vessel operating in the Danube sector. The research aims to assess the feasibility of harnessing wind energy under real navigation conditions and to quantify the electrical power generation potential across different operational states, including cruising, maneuvering, and standby. The system was designed with consideration for structural constraints, aerodynamic interference from the vesse...

Infrared (IR) absorption spectra are investigated hydrogenated amorphous solid solution films a-Si1-xGex: H (x = 0 - 1) plasma chemical vapor deposition at different partial pressures of hydrogen PH2. Defined force, oscillator, which essentially depended on PH2. It is shown that the hydrogen contained in films mostly in the forms of GeH, SiH. Using integrated acquisitions JW, determined the amount of hydrogen in the films. Film properties depend on the composition and level of hydrogenation. The number of hydrogen...

Making the automotive greener has led to a continuous intensification of studies for alternative technologies in road transport. The most promising of technology is based on electric propulsion. But beside many advantages, the electric vehicles have some disadvantages compared to conventional vehicles: limited driving range, long charging times, and insufficient charging infrastructure in some areas. Additionally, battery degradation over time (especially due to operation in extreme weather conditions in winter an...

Transport represents one of the key sectors in terms of greenhouse gas emissions within the European Union and, at the same time, an area with a growing demand for both passenger and freight transport. Despite increasing energy efficiency, the European transport system remains largely dependent on fossil fuels and significantly contributes to CO2 emissions as well as to economic losses caused by traffic congestion. Strategic documents of the European Union, particularly the White Paper, envisage a substantial redu...

Amorphous aromatic polymers synthesized by the knitting method are promising supports in catalysis, since they have high porosity (up to about 1000 m2/g) and can be synthesized by the simple one-step procedure using a variety of available aromatic monomers [1-4]. In catalysis, the stability of active phase is typically discussed, while the stability of polymeric support remains outside the scope. At the same time, many reactions require high temperature or application of strong acids or bases. In this work, a seri...

Europe is undergoing a transition toward renewable heating and cooling, and borehole heat exchanger systems play a critical role in this energy shift. However, their efficiency depends heavily on site-specific and local climatic conditions. This study evaluates BHE design and performance across 11 European capital cities that represent diverse climatic conditions, from hot/dry (Nicosia, 21.56 C, undisturbed ground temperature) to cold/humid (Helsinki, 6.76 C). A representative university building was virtually rel...

As part of this study, a comprehensive thermogravimetric analysis of biomass oxidation was conducted to study its thermal decomposition and determine its kinetic characteristics in an oxidative environment. This work is of great importance for the development of sustainable energy, the optimization of combustion and co-combustion processes, and the minimization of environmental damage through more efficient use of biomass. The experiments involved measuring the mass change of biomass samples (sawdust from hardwood...

This paper aims to present an innovative approach to maritime transportation solutions and the need to minimize gas emissions and fuel consumption through green hydrogen research and substitution. Given its critical role in global commerce, maritime transportation has been a key factor for the past decades, specifically regarding the optimization of ship routing. The traditional focus on minimizing distance has been supplemented with modern, sustainability-driven objectives, including greater attention to fuel con...

The study-s aim is to assess the economic and environmental benefits of onshore power supply (OPS) implementation in port areas and to evaluate its cost-effectiveness under different energy price and emission trading scenarios. Specifically, the research investigates how OPS adoption impacts total annual costs, emissions of NOX, SO2, PM, and CO2, and overall cost-effectiveness expressed in euros per pollution unit. A quantitative simulation approach was employed using the OPS Calculation Tool, an Excel-based model...

Accurate, real-time characterization of drilling fluid rheological properties, such as plastic viscosity, yield stress, and gel strength, is vital for optimizing oil and gas drilling operations and advancing sustainable exploration. This study assesses advanced sensor technologies - ultrasonic sensors, inline viscometers, optical flow analyzers, and microfluidic sensors-for automated, real-time measurement of these properties in water-based, oil-based, and synthetic-based muds. Experiments utilized a closed-loop f...

Natural hydrogen (H2), produced through geological processes in the subsurface, is a potential energy source and is a substantial element of the global energy strategy for a smooth transition to carbon neutrality. The review of the published papers concerning the results of the natural hydrogen exploration, which have been carried out over the past few years, shows that the petroleum system concept could be transformed for the exploration of natural hydrogen. The present research is a case study for applying this ...

Global climate change and the need to transition to clean energy sources have brought green hydrogen to the forefront of regional and international energy strategies. Green hydrogen offers a low-carbon solution that can support decarbonization in the heavy industries, transportation, and industry sectors, and renewable energy sources can be integrated into its production. The Danube River is one of the primary hydrological axes in Central and Southeastern Europe, playing a strategic role in the region's energy and...

Mesoporous solids include metal oxides, silica, phosphates and other materials. They may contain various acidic and basic sites which are, in combination with metal nanoparticles, metal atoms, functional groups, etc., could be efficient multifunctional catalysts for cascade reactions. In this shot review, the most important aspects of such catalysts that furnish their catalytic activity and selectivity for cascade reactions in biomass processing discussed. A combination of one metal with another or with metal oxid...

The European Union-s (EU) ambition to accelerate the transition to renewable energies imposes the shift toward ecological mobility has become a key and very challenging task. High niche models of Battery Electric Vehicles (BEVs) are the flagmen in makers- competition but they are not accessible to the mass consumers. Mini and compact Battery Electric Vehicles (BEVs) are expected to play an increasing role in reducing urban congestion and emissions while promoting affordable and efficient transportation solutions. ...

Hydrogen is increasingly recognized as a promising energy carrier, but its storage poses significant safety challenges. One of the most common storage methods is the use of high-pressure Type I steel cylinders, where hydrogen is kept in gaseous form at variable pressures up to 1000 bar. Cylinders used in industrial processes are usually equipped with pressure or temperature-pressure relief devices, while transportation units often lack such protection. In accident scenarios, especially under fire exposure, cylinde...

This study investigates the propagation of hydrogen explosions in confined environments, focusing on the influence of geometry on explosion dynamics. Experimental models were developed to analyze the impact of spatial constraints on pressure rise and flame acceleration. Key parameters, including maximum pressure, flame front velocity, and pressure rise rate (dp/dt), were monitored and analyzed. The results highlight that changes in propagation direction significantly influence explosion behavior, leading to higher...

The decarbonization of the building sector and the recent disruption of energy markets has positioned Air Source Heat Pumps (ASHP) as a pivotal technology for reducing fossil fuel dependency and improving energy efficiency. However, their widespread deployment introduces challenges related to operational reliability, seasonal performance variability, and early fault detection. This study presents a data-driven approach for performance analysis and anomaly detection in real-world ASHP systems. Using five years of m...

Development of renewable energy systems can certainly contribute to climate change mitigation. In many regions initiatives can be noticed to succeed in increasing the efficient usage of renewable energy resources such as hydro power, solar and wind energy as well as bioenergy. From these resources the bioenergy and the hydro power by their storage possibilities have the potential to counterbalance the temporal variability of solar and wind energy. Anyway, by applying such renewable energy resources it is possible ...

Drilling fluid viscosity is a critical parameter influencing the efficiency and safety of drilling operations, yet real-time monitoring under dynamic conditions remains challenging due to varying temperature, pressure, and flow rates. This study develops algorithms for continuous, automated viscosity monitoring of drilling fluids to optimize drilling processes. The primary objective is to design robust algorithms capable of accurate viscosity predictions in real-time, addressing limitations of traditional manual m...

This work is aimed at the search of optimal conditions of selective hydrogenation of 2-methyl-3-butyn-2-ol (MBY) to 2-methyl-3-buten-2-ol (MBE). The main question was if the common slurry reactors are suitable for this reaction under ambient hydrogen pressure with the use of environmentally friendly solvents. Thus, we investigated the effect of the reactor type (shaker-type or slurry), temperature and solvent nature (isopropanol, n-butanol or toluene were used) on the behavior of a palladium catalysts (1 wt.% of P...

The urgent need to combat climate change has driven the search for sustainable transportation solutions. Electric vehicles (EVs) and hydrogen fuel cell vehicles (FCVs) have emerged as promising alternatives to traditional fossil fuel-powered cars, offering the potential to significantly reduce carbon emissions. This article provides a detailed analysis and comparison of these two technologies, focusing on their technical, economic, and environmental aspects. EVs rely on batteries to store electrical energy, which ...

The energy security of the Czech Republic (CR) and the European Union (EU) has become a key strategic issue over the past decade, as highlighted by the recent energy crisis caused by dependence on energy imports from geopolitically unstable regions. The field of energy security is a complex and strategic issue influenced by numerous factors. Technological advances, digitalisation, electromobility, the development of AI, geopolitical upheavals and the drive for decarbonisation are all increasing the demand for a st...

The article discusses the advantages of using cryogenic technology in the production of gravel filter elements. A method for calculating the main components for the production of temporarily monolithic annular gravel elements is described. An approach has been developed for the strength analysis of annular gravel filter bits, taking into account installation conditions and the effect of water flow in the aquifer. An analytical calculation was performed to determine the distribution of gravel packing in the behind-...

The charging time of Electric Vehicles (EVs) is an important parameter that greatly affects their operation. Its evaluation helps to estimate the distance traveled. The paper derives an analytical relationship that helps estimate the charging time of the remaining capacity of the EV battery. The relationship is based on a quadratic approximation of charging times for several categories of batteries with different capacities and charging stations with different power levels.

The transition to a sustainable energy system is one of the European Union's key strategic directions, in line with achieving climate neutrality by 2050, as outlined by the European Green Deal. The Black Sea region has considerable potential for renewable energy sources, particularly offshore wind, solar, and biomass. Due to this potential, the area has become a hub for European initiatives focused on increasing the share of renewable sources in the regional energy mix, and consequently, on energy security and red...

This paper focuses on analyzing the behavior of a photovoltaic system installed on a selected building, using the PVcase software to evaluate the influence of temperature on energy performance. The study simulates a typical summer day, comparing the operation of photovoltaic panels during two distinct periods: in the morning, when the ambient temperature is lower, and at midday, when the temperature reaches its peak. Through these simulations, variations in voltage, current, and generated power are determined, as ...

Hydrogen is considered the energy source which can ensure the global transition to sustainable low-carbon energy systems. Municipalities can become more eco-friendly by adopting and implementing hydrogen-based energy systems. At the beginning of the transition toward carbon neutrality, the municipalities can use the hydrogen mixed with natural gas in the existing natural gas network for food and domestic hot water preparation, and heating and electricity generation, and the hydrogen stored as compressed gas, cryo-...

Energy remains a key driver of human development and economic growth. The projected increase in the global population to 8.5 billion by 2030 will intensify energy demand and dependence on fossil fuels, the main source of CO2 emissions. This highlights the urgent need for renewable and sustainable energy solutions. Hydrogen is considered a promising clean energy carrier; however, most hydrogen is still produced from natural gas via steam reforming, releasing significant amounts of CO2. Growing attention is therefor...

The disadvantage of generating electricity from renewable sources is the need for its simultaneous consumption afterwards or distribution to other consumers over long distances, which is accompanied by significant energy losses in networks with increasing transportation distances. In addition, there is a discrepancy between the seasonal maximum volumes of electricity generation and consumption. Thus, imbalances arise between the demand and supply of electricity on the market. This problem can be solved by converti...

Solar thermal energy is a widely established source for Domestic Hot Water (DHW) production. However, standard DHW systems rely on external electrical energy to power auxiliary components such as circulation pumps and automation controls. This paper aims to demonstrate the feasibility of a self-sustaining system capable of simultaneous thermal energy recovery and electrical generation, thereby enhancing overall energy efficiency and reducing the carbon footprint. Experimental investigations were conducted on a cus...

In previous studies, when conducting a geospatial analysis of 297 degraded territories in Latvia, it was found that 6.7% of them would be suitable for electricity production with renewable energy resources and approximate calculations of the possible electricity production potential were made. The task of the study was to conduct an in-depth study of the degraded territory found in the previous analysis in an area of 11.0 ha, taking into account the location of the territory in relation to the daily movement and a...

Hydrogen integration represents a promising strategy for decarbonizing Floating Production, Storage and Offloading (FPSO) operations, which traditionally rely on gas turbines and diesel generators. This study proposes a hybrid FPSO concept combining renewable energy generation with onboard hydrogen production, storage, and utilization. The system emphasizes green hydrogen produced by renewable-powered electrolysis of desalinated seawater, supported by blue hydrogen from associated gas reforming with carbon capture...

Rapid growth of world population and economic activities continue to cause the increase of anthropogenic greenhouse gases (GHG) emissions. To mitigate GHG emissions and limit global warming, researchers and practitioners around the globe search for clean energy solutions. Many researchers believe that hydrogen (H2), with its high energy density, has a promising potential. Yet, practical implementation of H2-based energy generation faces technical and economic challenges. So far, over 95% of global hydrogen product...

This paper analyses the current development status of hydrogen production technologies and projects global demand growth through 2050. Production costs and CO2 emissions per kilogram of hydrogen are identified as key factors influencing the adoption of hydrogen technologies. While fossil-based methods currently offer cost advantages, electrolysis and biological processes demonstrate superior performance regarding CO2 emissions. Provided that sufficient investments are made, the cost of renewable energy production ...

Levulinic acid (LA) obtained by processing of plant biomass is used to synthesize many important compounds, among which is gamma-valerolactone (GVL) - a platform chemical. At present, bifunctional catalysts based on inorganic supports are the most widespread in the reaction of selective hydrogenation of LA to GVL. Polymers can serve as promising alternative to inorganic supports. In the framework of the presented study, the series of amorphous aromatic polymers was synthesized using different monomers: phenanthren...

This paper analyses the implementation of recent geospatial technologies to map and model underground natural gas networks in three dimensions, with a focus on the use of mobile LiDAR scanning systems. The research focuses on the Subcetate area in the municipality of Arad, a representative example for the technical-urban networks in western Romania. The main objective is to create a geospatial database (GIS) with a high degree of accuracy, which would include the information collected from the site about the route...

The Heat Transfer Coefficient (HTC, h) is critical for evaluating the thermal performance of Trombe Walls (TW), passive solar heating systems that utilize solar energy for space heating. This study analyzes convective and radiative HTC mechanisms on a TW absorber surface, emphasizing factors such as airflow patterns, surface roughness, temperature gradients, emissivity, and environmental conditions (solar radiation, ambient temperature, wind speed). Experimental and numerical methods were applied to quantify HTC f...