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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...

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.

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...

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...

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...

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...

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 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...

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...

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...

Global climate and ecological crisis urge to decarbonazation of EU through sustainable low carbon alternatives to achieve carbon neutrality by 2050. Within this context, Power-to-Hydrogen-to-Power (P2H2P) technologies are playing an essential role in the energy transitions boosting the energy system flexibility, facilitating the integration of renewable energy sources and providing a promising pathway for long-term energy storage and clean fuel supply. Driving forces behind this research are the imperative raise t...

The article presents directions for improving diamond drill bits designed for drilling in hard abrasive rocks. The first direction involves the development of multilayer tools in which impregnated diamond layers are separated by soft, non-diamond interlayers of the same configuration. Additionally, ring-shaped bits have been developed with diamond-bearing layers placed on the concave surface of the matrix. This design enables the use of a weakened rock zone beneath the working elements, enhancing rock-breaking eff...

This paper presents the modeling and simulation of an electrical energy management system that integrates a 300 V, 8 Ah lithium-ion battery, a DC shunt machine, and a variable DC load using NEPLAN simulation software. The main purpose of this work is to investigate the performance and control behavior of a hybrid electrical system where the power flow is automatically regulated according to the State of Charge (SOC) of the battery. The DC machine alternates between motor and generator modes depending on the SOC le...

One of the directions towards a green energy transition is the spread of electric vehicles in the transportation sector. This necessitated the installation of electric charging stations, but as their number increases, so do the problems with their management and the increasing consumption of electricity. In this regard, there is a need to search for intelligent management solutions in the transition to alternative energy sources. This research is related to the development of a project to build a smart system for ...

Complex energy systems, in the current period of transition to a climate-neutral society, comprise two fully functional subsystems, that of fossil fuel-based production and that of production from renewable energy sources. The functional coexistence of these subsystems is achieved due to the capture of the CO2 component from flue gases through the energy vector represented by green H2. This takes on both the role of energy accumulation and the role of transforming the CO2 component, captured during the combustion ...

In the last century human society has registered huge development in all human-related fields, fact that has been possible without doubt by designing technological applications with the usage of diverse natural resources, especially energy ones. Anyway, recorded progress, especially in technological fields, was feasible because of using fossil fuels for electric and thermal energy supply, which resulted besides positive impacts in undesired environmental pollution. Currently most debated effect by CO2 emissions is...

All nuclear power plants in Slovakia can effectively prevent emergencies caused by technical or human error. Before commissioning, they must demonstrate to the Nuclear Supervisory Authority that the plant can respond to even extremely unlikely events. The design of the plant has safety systems that will prevent damage to nuclear fuel and the release of radioactive substances so as not to endanger human health and the environment. The maximum design accident for a WWER-440 reactor is a rupture of the main circulati...

Achieving efficient energy systems has become a challenge for researchers, as many engineering applications combine convective heat transfer in fluid saturated porous media, such as nuclear reactors, hydrogen production and storage, underground disposal of waste, food processing and storage, solar power collectors or geothermal systems. For this purpose, it is essential to calculate energy losses and identify methods that involve minimal costs. The paper presents a problem of free convection for a fluid flow throu...

The transition to renewable energy sources is a key strategy for reducing carbon emissions and ensuring energy sustainability. This study explores the integration of photovoltaic (PV) systems for hydrogen production and storage in Constan?a County, Romania. The region benefits from high solar potential, making it an optimal location for implementing solar energy solutions. The proposed system converts solar energy into electricity through photovoltaic panels, which is then used to power an electrolyzer for hydroge...

As the offshore oil and gas industry faces mounting pressure to reduce its carbon footprint, Floating Production, Storage and Offloading (FPSO) units are emerging as critical platforms for implementing clean energy innovations. This paper explores the potential for integrating renewable energy sources such as offshore wind, solar photovoltaic, and wave energy with advanced energy storage technologies, including lithium-ion batteries and hydrogen-based systems, within FPSO operations. The hybridization of power gen...

The maritime industry represents a significant contributor to global greenhouse gas emissions, primarily through the combustion of fossil fuels used by ship engines. As international regulations tighten and environmental awareness grows, reducing global greenhouse gas emissions from ships has become an important objective. This study explores the potential for emission reduction on passenger ships through the implementation of a hybrid propulsion system. The study methodology involves solving the following aspects...

During the process of adapting renewable energy and ensuring national energy security in the current geopolitical context, technological progress in the field of green energy has received increased attention. This has led to the development of updated policies on investment in onshore renewable energy (which uses wind and solar energy through wind turbines and photovoltaic parks) and offshore renewable energy (which uses tidal, wave, solar, and wind energy through floating photovoltaic parks and wind turbines that...