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In the quest of renewable energy technologies, solar photoreforming emerges as one of the affordable yet challenging process for converting biomass into hydrogen, hydrocarbon fuels, and chemicals. This review highlights the state‐of‐the‐art photoreforming, elucidating its underlying mechanisms for the conversion of dissipated polymers into H2 and valuable chemicals. Biomass feedstocks such as carbohydrates, agricultural residues, glycopolymers, food wastes, and waste plastics are evaluated based on their chemical composition, energy content, and sustainability aspects, exploring the selection of appropriate bio‐renewable resources, considering their abundance, availability, and potential for hydrogen production. The impact of diverse process parameters on photoreforming efficiency is explored, encompassing factors like reaction temperature, pH, catalyst loading, reactor design, solvent effect, and light intensity across various sacrificial substrates. The discussion also considers their correlation with hydrogen production rate, selectivity, and energy efficiency. This review buckles on the design and synthesis of functional photocatalysts for biomass‐derived feedstock, highlighting their photocatalytic (PC) properties in biomass reforming processes and related feedstock into valuable chemicals and biofuel. The review also delves into potential pathways for future advancements including artificial intelligence (AI) and machine learning (ML), alongside addressing the challenges and insightful perspectives within this evolving field of future green energy. [ABSTRACT FROM AUTHOR]

To achieve zero carbon emissions, replacing conventional fuels in combustion engines and gas turbines with carbon-free fuel is of utmost important. While hydrogen is effective in mitigating climate change, the cost challenges in liquefaction and transportation persist. Ammonia (NH 3), a carbon-free fuel with its higher volumetric energy density and cost advantages, emerges as a potential substitute. This review reports the most recent studies on NH 3 as a fuel for micro gas turbine (MGT), highlighting both advantages and limitations. The performance and emissions in gas turbines are discussed. The main obstacles to a widespread usage of NH 3 blends as fuel for MGT power generation are addressed, along with the current stage of commercialization. The review explores all the numerical and experimental works on NH 3 blend in combustion system of MGT, and further presents ways to overcome the limitations associated with the combustion, such as high NO x emissions and low burning velocity. [Display omitted] • A comprehensive analysis of ammonia blend reactive fuels for micro gas turbine power generation is presented. • Advantages and limitations of ammonia combustion in micro gas turbine over hydrocarbon fuels are summarized. • The issues that hinder a widespread usage of ammonia and ammonia/blend as fuel for micro gas turbine are addressed. • The current stages of commercialization are discussed. • Possible approaches to overcome ammonia combustion barriers in micro gas turbine are highlighted for future research. [ABSTRACT FROM AUTHOR]

It has been established that the needs of mankind in fuel are growing every day. The full energy balance of the countries of the European Union is analyzed and the place and share of alternative energy sources are determined. It is determined that trends in the development of society require the adoption of new, non-traditional solutions that can quickly increase the efficiency of using alternative energy sources, solve the problem of insufficient energy capacity, reduce the harmful impact on the environment and carry out modernization in the shortest possible time and at the lowest cost. The main reasons for this are the expected depletion of fossil fuel reserves, the rapid rise in prices for it, incomplete use and low efficiency, as well as the harmful impact on the environment. The problems of the energy sector of economy are determined. The use of alternative energy sources by EU countries is evaluated, which saves billions of euros on gas purchases. It is proved that despite the rapid changes in demand and oil prices, the tendency to increase the consumption of fuel and energy resources will continue, although the distribution of consumption by industries and countries may change somewhat. A review of theoretical approaches to defining the essence of the concept of «alternative energy» is made and the author's definition of this economic category is provided. Each type of alternative energy sources is characterized, their advantages and disadvantages, which positively or negatively affect the energy sector of the economy and the economy as a whole, are outlined. The problematic issues of using alternative energy sources in modern conditions of management are outlined. It is noted that in recent years, the cost of building small hydropower plants has been significantly simplified by simplifying their design and operation, standardizing design solutions, unifying equipment and full automation of HPP operation, as well as through the use of new materials and finished products. It is proposed to use new unconventional energy technologies that we have explored and can lead the world towards a sustainable energy supply.

The article considers the prospects for Azerbaijan's participation in the diversification of energy supplies to the European market, in the conditions of the energy crisis due to the difficult geopolitical situation in the world. Possible ways to reduce the serious risks of failures in the supply of energy resources while ensuring the energy security of the countries of the European continent are given. The negative impact of the crisis that has arisen in the energy market on the global energy supply chain to the EU countries and on the state of the world economy is analyzed. Steps taken by the EU to radically increase supply via traditional EU import routes as well as completely new sources of energy are examined. Various measures implemented by European countries to ensure their own energy security, including the diversification of the supply of energy resources used to generate energy, including through non-renewable mineral substances, renewable organic resources and a number of natural processes, are considered. The ongoing measures in connection with the energy crisis have been considered in order to reduce the negative consequences for the economies of the EU countries. The high potential of Azerbaijan is noted as a country rich in energy resources, and having all the necessary opportunities to influence the state of the gas market in Europe and diversify energy resources in the EU countries by expanding the export of Azerbaijani gas. [ABSTRACT FROM AUTHOR]

In the present energy transition scenario, ammonia is considered a valuable candidate as energy-dense carrier with neutral or even negative carbon balance. However, the potential high NO x emissions and the reduced oxidation process stability, at least when conventional combustion plants are used, can burden its wide utilization on large scales. In this context, MILD Combustion, due to its inherent characteristics, may greatly improve combustion stability and keep the NO x emissions at an acceptable level. On the other hand, the addition of low or no-carbon fuels from biomasses and wastes, more reactive than ammonia, may be beneficial in further improving its combustion performance and the global sustainability of the energy supply chain. In this respect, the present work analyzes the sustainability and combustion performance of binary mixtures of ammonia and low-molecular-weight alcohols in a cyclonic burner, where MILD conditions are attained by means of a strong internal recirculation, and compares them with those obtained with NH 3 /methane blends. Results highlighted that NH 3 /alcohols mixtures ensure a stable oxidation process in a wide range of operational parameters without compromising the system performance. Moreover, they showed a significant reduction of NO x emissions for NH 3 /alcohols mixtures, especially for fuel-lean conditions, when compared to NH 3 /methane blends. Experimental data were also corroborated by chemical kinetic modeling results to provide some insights on the peculiar NO x formation routes when blends of different nature are used, highlighting the interaction between carbon and nitrogen fuels kinetics. [ABSTRACT FROM AUTHOR]

In this research article, we uphold the principles of the No Free Lunch theorem and employ it as a driving force to introduce an innovative game-based metaheuristic technique named Golf Optimization Algorithm (GOA). The GOA is meticulously structured with two distinctive phases, namely, exploration and exploitation, drawing inspiration from the strategic dynamics and player conduct observed in the sport of golf. Through comprehensive assessments encompassing fifty-two objective functions and four real-world engineering applications, the efficacy of the GOA is rigorously examined. The results of the optimization process reveal GOA's exceptional proficiency in both exploration and exploitation strategies, effectively striking a harmonious equilibrium between the two. Comparative analyses against ten competing algorithms demonstrate a clear and statistically significant superiority of the GOA across a spectrum of performance metrics. Furthermore, the successful application of the GOA to the intricate energy commitment problem, considering network resilience, underscores its prowess in addressing complex engineering challenges. For the convenience of the research community, we provide the MATLAB implementation codes for the proposed GOA methodology, ensuring accessibility and facilitating further exploration. [ABSTRACT FROM AUTHOR]

Background: Current threats connected to the ongoing depletion of fossil resources and elevated levels of greenhouse gases accelerating climate change and global warming provoke a renaissance of biotechnological production of various organic bulk chemicals, which, particularly during the second half of the 20th century, were almost exclusively produced from fossil resources via chemosynthetic processes.

The countries of the European Union are experiencing the first real global energy crisis in history, bearing in mind that reliability and the possibility of receiving the required amount of energy resources are the basis of full functioning and further sustainable social and economic development of countries. The purpose of the study is to analyse European Union energy and environmental security regulatory measures in terms of unpredictable actions of the main supplier of energy resources. A set of general scientific and special methods of scientific cognition was used: the historical method with a systematic analysis of energy law; the structural and functional method; synthesis; deduction and induction. As a result of the conducted study, the main areas of increasing energy security in the European Union were determined based on scientific programmes using renewable energy sources, which gradually reduce the demand for organic fossil fuels (natural gas, oil, coal, peat, oil shale). The situation of dependence of EU states on the export of russian energy resources was also characterised and the process of changing the EU energy policy was illustrated. This research contains an analysis of the ecological aspect of the change in the situation with energy security in the EU, and forecasts regarding the situation on the international energy market of russia. The primary theoretical principles, conclusions, and practical recommendations in the industry of the energy market would help accelerate the diversification of the natural gas market in Ukraine in terms of joining the European Union energy market

The article is devoted to the definition and research of environmental and economic criteria for the assessment of energy carriers used for the buildings heating. The criteria for the comparison are based on the amount of heat and the emission of pollutants into the atmosphere. Various options for the use of energy carriers and corresponding design schemes of heating systems, the most often used in residential buildings, are considered. Calculations of the cost of thermal energy received for heating the building using common types of fuel (coal, firewood, pellets), electricity, and centralized heat supply were made. Also, a comparative assessment of the specific emissions of pollutants for boilers operating on natural gas, hard coal, firewood, and pellets was carried out based on the averaged indicators. It has been established that the minimum cost of a unit of heat is achieved when burning pellets, firewood, but the use of such energy sources leads to additional labor costs, and the most comfortable and least time-consuming is the use of central heating services, a gas or electric boiler with a water heating system. It was determined that considering the impact on the environment at the heated object location, the most safe are a boiler running on natural gas, a centralized heat supply, an electric boiler. Ways to reduce the cost of a thermal energy unit supplied to the building are proposed by using heat pumps. An assessment of the cost of thermal energy supplied to the building using a heat pump was carried out, which showed a significant reduction in the cost of thermal energy supplied to the building in the case of using a heat pump in various variants of the design features of the heating system considering climate conditions compared to options without the use of a heat pump

The effective usage of renewable energy sources requires ways of storage and delivery to balance energy demand and availability divergences. Carbon-free chemical energy carriers are proposed solutions, converting clean electricity into stable media for storage, long-distance energy trade and on-demand electricity generation. Among them, hydrogen (H2) is noteworthy, being the subject of significant investment and research. Metal fuels, such as iron (Fe), represent another promising solution for a clean energy supply, but establishing an interconnected ecosystem still requires considerable research and development. This work proposes a model to assess the supply chain characteristics of hydrogen and iron as clean, carbon-free energy carriers and then examines case studies of possible trade routes between the potential energy exporters Morocco, Saudi Arabia, and Australia and the energy importers Germany and Japan. The work comprises the assessment of economic (levelized cost of electricity - LCOE), energetic (thermodynamic efficiency) and environmental (CO2 emissions) aspects, which are quantified by the comprehensive model accounting for the most critical processes in the supply chain. The assessment is complemented by sensitivity and uncertainty analyses to identify the main cost drivers. Iron is shown to be lower-cost and more efficient to transport in longer routes and for long-term storage, but potentially more expensive and less efficient than H2 to produce and convert. Uncertainties related to the supply chain specifications and the sensitivity to the used variables indicate that the path to viable energy carriers fundamentally depends on efficient synthesis, conversion, storage, and transport. A break-even analysis demonstrated that clean energy carriers could be competitive with conventional energy carriers at low renewable energy prices, while carbon taxes might be needed to level the playing field. Thereby, green iron shows potential to become an important energy carrier for long-distance trade in a globalized clean energy market.

The shift toward renewable energy generation sources, characterized by their non‐carbon emitting but variable nature, has spurred significant innovation in energy storage technologies. Advancements in foundational understanding from investments in basic science and clever engineering solutions, coupled with increasing industrial adoption, have resulted in a notable reduction in the cost of storing electricity from variable energy generation sources. These developments have paved the way for the exploration of new and innovative forms of energy storage that deviate from traditional technologies. In this perspective, it is posited that the progress made in energy storage research over recent years has opened the door to the development of energy carriers for technologies that are yet to be realized. To illustrate this concept, examples of alternative energy carriers are provided within the context of unique electrochemical interfaces for electrochemical hydrogenic transformations. The unique properties of these interfaces and electrochemical systems can be leveraged in ways not yet imagined, creating new possibilities for energy storage. A perspective on the progress and challenges for each interface as well as a general outlook for the advancement of energy carrier systems are provided. [ABSTRACT FROM AUTHOR]

The pandemic and the war have had a negative economic impact on the world economy. The current structure of the energy market poses a major challenge to national governments, businesses, and households alike, and new strategies need to be developed to focus on energy efficiency. Hungary has also been strongly affected by this situation, which has had an impact on all areas of residential consumption. The present study, based on a primary questionnaire survey carried out in October-November 2022 with 273 evaluable responses, aims to explore the opinions and perceptions of students at a business university in Hungary regarding the energy crisis. The goal is to establish their knowledge about the gas situation and how it is reflected in their consumption practices and savings. The results of a survey of students at the Budapest University of Economics and Business show that young people studying economics are not really aware of the gas market situation in Hungary, but their gas saving habits are characterized by awareness and not primarily motivated by their financial situation. [ABSTRACT FROM AUTHOR]

Methanol and ammonia emerge as two of the most important energy carriers in a new decarbonized society. In this work, a systematic assessment of the power generation based on these chemicals is performed using two different alternatives: direct utilization as green fuels in fuel cells or as carriers for hydrogen. Despite the need for a previous stage for hydrogen production, the use of these chemicals as hydrogen carriers demonstrates higher efficiencies (around 40%), mainly due to the higher degree of maturity of the hydrogen fuel cells. This is reflected in the cost of electricity for the different alternatives with around 700 €/MWh for hydrogen carrier options and about 1200 €/MWh for the direct utilization as green fuels. Compared to hydrogen, the use of methanol or ammonia has a higher electricity production cost. However, future improvements in the efficiency of fuel cell units could convert these fuels is competitive options. In addition, for different scenarios combining transportation and power generation, methanol and ammonia emerge as technically and economically feasible alternatives, especially for distances over 3000 km. Consequently, both hold a pivotal role in addressing the challenges associated with hydrogen within a future energy systems characterized by high renewable penetration. • A techno-economic evaluation of using methanol/ammonia in fuel cells is performed. • The use of methanol/ammonia as hydrogen carriers is the preferred option. • The cost of electricity for the best alternatives ranges around 600–800 €/MWh. • To achieve competitive levels, the efficiency of direct fuel cells must be doubled. • For distances greater than 3000 km, methanol and ammonia show great potential. [ABSTRACT FROM AUTHOR]

Government control distorts energy prices which leads to loss of optimal factor combination and, as a result, affects efficiency. Previous researches on energy price distortions did not pay attention to the allocative efficiency specifically. In this paper, we empirically estimate the impact of energy carriers' price distortion on allocative efficiency in 28 Iranian provinces during 2002–2015 using Stochastic Frontier Analysis (SFA). Results indicate that energy carriers' price distortions affect allocative efficiency negatively. However, allocative efficiency increased in 2011 due to the energy price reform of 2010; it showed a downward trend in the following years which means that energy price reform was effective only in the short-term. The energy price distortion trend and inefficiency changes are similar in all regions; nonetheless, there are differences in the measures caused by differences in energy consumption, the existence of energy-intensive industries, and technical barriers. Furthermore, among the 28 provinces which are classified to 5 regions, region 2 has the lowest and region 3 has the biggest price distortion during the same period. [ABSTRACT FROM AUTHOR]

The article considers possible specific risks in the production and transportation of natural gas from Azerbaijan to the European continent in the context of the economic crisis in the world energy market. It is stated that the effective management of strategic, as well as specific risks, should be based on a comprehensive identification and description of the risks that determine the key indicators of the gas industry. The necessity of ways to minimize political and economic risks to ensure uninterrupted and reliable export of natural gas from the AR to the countries of the continent, including alternative routes for the transportation of natural gas, taking into account the risk of the transit country, is substantiated. [ABSTRACT FROM AUTHOR]

In this research article, we uphold the principles of the No Free Lunch theorem and employ it as a driving force to introduce an innovative game-based metaheuristic technique named Golf Optimization Algorithm (GOA). The GOA is meticulously structured with two distinctive phases, namely, exploration and exploitation, drawing inspiration from the strategic dynamics and player conduct observed in the sport of golf. Through comprehensive assessments encompassing fifty-two objective functions and four real-world engineering applications, the efficacy of the GOA is rigorously examined. The results of the optimization process reveal GOA’s exceptional proficiency in both exploration and exploitation strategies, effectively striking a harmonious equilibrium between the two. Comparative analyses against ten competing algorithms demonstrate a clear and statistically significant superiority of the GOA across a spectrum of performance metrics. Furthermore, the successful application of the GOA to the intricate energy commitment problem, considering network resilience, underscores its prowess in addressing complex engineering challenges. For the convenience of the research community, we provide the MATLAB implementation codes for the proposed GOA methodology, ensuring accessibility and facilitating further exploration.

The use of fossil fuels (methane, oil, etc.) is undergoing an unprecedented crisis now. There is the urgent need to search for alternative energy sources. A wide range of degraded organic materials can be effectively used to provide energy together with environmental protection. Soapstock is a hazardous waste containing a high concentration of toxic organic compounds of man-made origin (fatty acids, surfactants, dyes, etc.). To prevent environmental contamination such substances require an effective treatment approach. The goal of the study was to isolate the adapted-to-fatty-acids methanogenic microbiome and investigate the patterns of sodium acetate and soapstock degradation with simultaneous biomethane synthesis. The effectiveness of the degradation of sodium acetate and soapstock by non-adapted and adapted microbiomes was evaluated by decreasing the concentration of dissolved organic compounds. The effectiveness of the fermentation process was determined by the biogas (mixture of CH4 and CO2) yield. The most effective degradation occurred in the variant with sodium acetate and adapted methanogens and amounted to 77.9%. In other variants, the patterns and the efficiency of purification were similar ranging from 60.6 to 68.0%. The biomethane was mostly synthesized by adapted methanogens on the soapstock and sodium acetate as substrates. Thus, the CH4 yield was 368.4 L/kg of dissolved organic compounds or 127.5 L/kg of soapstock. The results of this study demonstrated the potential of methanogenic microorganisms in the biodegradation of soapstock with simultaneous biogas synthesis. The results can serve as a basis to reduce the reliance on fossil fuels by generating biomethane via the fermentation of toxic organics. [ABSTRACT FROM AUTHOR]

The article is devoted to the definition and research of environmental and economic criteria for the assessment of energy carriers used for the buildings heating. The criteria for the comparison are based on the amount of heat and the emission of pollutants into the atmosphere. Various options for the use of energy carriers and corresponding design schemes of heating systems, the most often used in residential buildings, are considered. Calculations of the cost of thermal energy received for heating the building using common types of fuel (coal, firewood, pellets), electricity, and centralized heat supply were made. Also, a comparative assessment of the specific emissions of pollutants for boilers operating on natural gas, hard coal, firewood, and pellets was carried out based on the averaged indicators. It has been established that the minimum cost of a unit of heat is achieved when burning pellets, firewood, but the use of such energy sources leads to additional labor costs, and the most comfortable and least timeconsuming is the use of central heating services, a gas or electric boiler with a water heating system. It was determined that considering the impact on the environment at the heated object location, the most safe are a boiler running on natural gas, a centralized heat supply, an electric boiler. Ways to reduce the cost of a thermal energy unit supplied to the building are proposed by using heat pumps. An assessment of the cost of thermal energy supplied to the building using a heat pump was carried out, which showed a significant reduction in the cost of thermal energy supplied to the building in the case of using a heat pump in various variants of the design features of the heating system considering climate conditions compared to options without the use of a heat pump. [ABSTRACT FROM AUTHOR]

As a result of particular locations of large-scale energy producers and increases in energy demand, transporting energy has become one of the key challenges of energy supply. For a long-distance ocean transportation, transfer of energy carriers via ocean tankers is considered as a decent solution compared to pipelines. Due to cryogenic temperatures of energy carriers, heat leaks into storage tanks of these carriers causes a problem called boil-off gas (BOG). BOG losses reduce the quantity of energy carriers, which affects their economic value. Therefore, this study proposes to examine the effects of BOG economically in production and transportation phases of potential energy carriers produced from natural gas, namely; liquefied natural gas (LNG), dimethyl-ether (DME), methanol, liquid ammonia (NH3), and liquid hydrogen (H2). Mathematical approach is used to calculate production and transportation costs of these energy carriers and to account for BOG as a unit cost within the total cost. The results of this study show that transportation costs of LNG, liquid ammonia, methanol, DME, and liquid hydrogen from natural gas accounting for BOG are 0.74 $/GJ, 1.09 $/GJ, 0.68 $/GJ, 0.53 $/GJ, and 3.24 $/GJ, respectively. DME and methanol can be more economic compared to LNG to transport the energy of natural gas for the same ship capacity. Including social cost of carbon (SCC) within the total cost of transporting the energy of natural gas, the transportation cost of liquid ammonia is 1.11 $/GJ, whereas LNG transportation cost rises significantly to 1.68 $/GJ at SCC of 137 $/t CO2 eq. Consequently, liquid ammonia becomes economically favored compared to LNG. Transportation cost of methanol (0.70 $/GJ) and DME (0.55 $/GJ) are also lower than LNG, however, liquid hydrogen transportation cost (3.24 $/GJ) is still the highest even though the increment of the cost is about 0.1% as SCC included within the transportation cost.

Due to the necessity of cognizance of demand for the various forms of energy in the agricultural sector in Iran’s economy and considering the effects of price liberalization policies on forms of energy, analysis of the main energy carriers’ demand is very important. This study used the LA-AIDS approach and ISUR technique to estimate the demand and elasticities for various energy carriers. Also, the welfare effects of increasing energy prices under the 20, 40, 60, 80 and 100% scenarios are evaluated using the compensating variation (CV). The uncompensated and compensated own-price demand elasticities for oil products, electricity and, natural gas carriers were −1.21, −0.85 and −0.55, and −0.98, −0.32 and −0.30, respectively, confirming the demand theory. The cross-price elasticities showed that electricity has substitutability and complementarity relationship with oil products and natural gas, respectively, while the relationship between natural gas and oil products is a substitutability relationship. The income elasticities of energy usages estimated to be 0.64, 1.2 and 1.05. Agricultural producers’ welfare would experience a further decrease in oil products and electricity price liberalization, though the welfare impacts of natural gas are trivial. As price elasticity is different in the agricultural sector, price policies, then price liberalization and omitting energy subsidy should be applied based on the elastic or inelastic of energy carriers. The price policies effectiveness on oil products is more than electricity and natural gas. Given the prevalence of consumption and high price elasticities of oil products and pollutants, rising oil prices can reduce their consumption and environmental pollution.

Motivation: The concept of sustained development has been implemented on an increasingly large number of areas of human activity. Energy is one of those areas in the European Union in which this idea is used.Aim: The aim of this study is to assess the energy generation development in Poland and in the other EU countries in the context of sustainable development policy.Results: Considering the highly diverse environmental circumstances, not all countries are likely to meet the ambitious objectives of the EU energy policy in the area of environmental conservation without having to make sacrifices in the socio-economic area. Taking into account the EU’s enormous dependence on external supplies of energy carriers, it seems justified to use the concept of sustainable energy security, taking into account the social and technical conditions of individual countries.

Objectives. The synthesis of high-viscosity oils is a fundamental aspect of oil refinement and contributes toward improvements in their production technologies. However, current methods of oil extraction are characterized by the inefficient use of energy resources. Therefore, refinement costs continue to increase. Furthermore, high production emissions affect the environment. For example, the Duosol-type process uses a large quantity of gas used in solvent recovery units in existing furnaces, and excess heat is wasted. Additionally, oil dewaxing plants use water steam, whose condensate can be contaminated with petroleum products or ketone-aromatic solvents. The purpose of this study was to identify ways of improving the efficiency of high-viscosity oil production technologies for energy efficiency and environmental safety as well as prove the feasibility of computational methods of oil production plants’ improvement.Methods. The heat quantity required for high-viscosity oil production is calculated using a thermal equation and data obtained from industrial equivalents, empirical dependencies, and reference data. The heat capacities and heat quantities of Duosol and dewaxing plants are calculated using conventional methods based on the heat recovery principle.Results. At the solvent regeneration unit of a Duosol plant, excessive heating of the cube in one of the distillation columns was measured, leading to excessive heat consumption. This may result in contamination of the low boiling distillation component with water—one of the still bottom mixture components. Calculations show that the furnace should be divided into two chambers to lower the temperature of the column cube to help solve this problem. Water steam is currently used in the raw material preparation unit of the dewaxing plant. It has been found, however, that the quantity of heat carried away by the flue gases of the furnaces is sufficient to heat the raw material preparation unit of the oil dewaxing plant if water steam is completely excluded from this operation.Conclusions. Technology improvement at Duosol and dewaxing plants, which are part of the process of obtaining high-viscosity oils at refineries, is possible through the effective redistribution of energy resources.

This article discusses the examination of energy carriers like hydrogen, natural gas and LPG in regards to their combustion enthalpy with simple school experiments. As a continuation of Part I of the comparative analysis of the energy carriers hydrogen, natural gas and LPG, the measurements and results will be optimized in this publication. The optimization of the measurement results succeeds with more elaborate experimentation material. Therefore, the experiments will be more demonstration experiments rather than student experiments. Due to the use of the combustion calorimeter the results are close to literature values for calorific values. [ABSTRACT FROM AUTHOR]

The purpose of the presented research is to analyse possible methods of thickening of the Microcystis aeruginosa (Kützing) Kützing cyanobacteria using the obtained concentrate as a biomass for the production of energy carriers and biologically valuable substances. Method of cyanobacteria thickening under the action of electric current and in the electric field, as well as the method of coagulation–flocculation and gravity thickening, was experimentally investigated in labscale conditions. Electrical methods didn't show positive results for the Microcystis aeruginosa thickening, despite the reports of their potential efficiency in a number of previous studies. The high efficiency of the method of coagulation– flocculation and gravity thickening of Microcystis aeruginosa suspensions was obtained. The optimum concentrations of industrial polymeric coagulants and flocculants for the thickening of Microcystis aeruginosa suspensions were defined in the range of about 10 ppm for the coagulants and about 1 ppm for the flocculants. Negative effect of the previous cavitational treatment of the diluted suspensions of Microcystis aeruginosa on the effectiveness of the coagulation–flocculation and gravitational thickening was confirmed experimentally. Hydrodynamic cavitation should be recommended to use after the thickening as the next step of processing of concentrated suspensions of Microcystis aeruginosa to achieve maximum extraction of energy carriers and biologically valuable substances.

The use of fossil fuels (methane, oil, etc.) is undergoing an unprecedented crisis now. There is the urgent need to search for alternative energy sources. A wide range of degraded organic materials can be effectively used to provide energy together with environmental protection. Soapstock is a hazardous waste containing a high concentration of toxic organic compounds of man-made origin (fatty acids, surfactants, dyes, etc.). To prevent environmental contamination such substances require an effective treatment approach. The goal of the study was to isolate the adapted-to-fatty-acids methanogenic microbiome and investigate the patterns of sodium acetate and soapstock degradation with simultaneous biomethane synthesis. The effectiveness of the degradation of sodium acetate and soapstock by non-adapted and adapted microbiomes was evaluated by decreasing the concentration of dissolved organic compounds. The effectiveness of the fermentation process was determined by the biogas (mixture of CH4 and CO2) yield. The most effective degradation occurred in the variant with sodium acetate and adapted methanogens and amounted to 77.9%. In other variants, the patterns and the efficiency of purification were similar ranging from 60.6 to 68.0%. The biomethane was mostly synthesized by adapted methanogens on the soapstock and sodium acetate as substrates. Thus, the CH4 yield was 368.4 L/kg of dissolved organic compounds or 127.5 L/kg of soapstock. The results of this study demonstrated the potential of methanogenic microorganisms in the biodegradation of soapstock with simultaneous biogas synthesis. The results can serve as a basis to reduce the reliance on fossil fuels by generating biomethane via the fermentation of toxic organics.

Our ability to forecast future Land use/cover changes (LUCC) is extremely limited due to lack of understanding of how rapid and drastic changes like socio-economic shocks and disturbances (e.g., policy changes and economic crises) affect land use/cover. Energy policies changing in Iran have been implemented since 2010. In this study, we explored whether changes in energy policies affect the sustainability of forest cover and LUCC. Results showed that in the time periods of before and after implementation of the policies, 2,841 and 3,155 ha of forests converted to other land covers, respectively. It was also revealed that forest and rangelands degradation and their conversion to croplands and built-up areas have had the most contribution to increasing area of these land covers. Calculation annual rate of deforestation showed an increase in deforestation activities after the plan (−0.40% versus −0.53%). On the other hand, the population growth in the first period was 10,074 people, which was higher than the population increase in the second period (9,803 people). Therefore, it can be argued that the effect of the energy policies is likely to be greater than the increase in population and it appears to be able to cause a transition of land systems. [ABSTRACT FROM AUTHOR]

Purpose. In the present article, a new approach of the energy grid studies is introduced to program energy carriers. In this view, a proper plan is designed on the use of energy carriers considering the energy optimum use. Indeed, the proper energy grid is designed by applying Iran energy balance sheet information. It is proper to mention that, the energy grid modelling is done in a matrix form. The electrical energy distribution among power stations is achieved by using the particle swarm optimization algorithm. In the present paper, concerning the dynamic programming method, it is tried to determine a suitable combination of energy carriers.

The purpose of this study is to measure the effect of consumption of different kinds of energy carriers in Iran, which caused poverty and inequality in the process of economic, social and cultural development of countries. For this purpose, we use annual data from 1984 to 2010 through a simultaneous equations model using Two-Stage Least Square (2SLS) and Three-Stage Least Square (3SLS) estimators. The results indicate that the effect of various energy carriers on inequality is different. Gasoline consumption leads to inequality enhancement but natural gas and electricity consumption lead to inequality reduction. Fuel oil, kerosene and gasoil have the different effects on inequality due to different indexes of inequality. On the other hand, energy carrier consumption leads to poverty reduction and natural gas and electricity are more effective to reduce poverty. Thus, the direct effect of energy consumption on poverty is confirmed. Totally, the results indicate that the indirect effect of all energy carriers on poverty trough inequality reduction is not confirmed, though all energy carriers on economic growth has a positive effect, and the indirect effect of economic growth on poverty reduction is confirmed.

Basic technologies for crude oil conditioning and transportation and the processing of various petroleum feedstocks are considered from the viewpoint of methods for their improvement, energy saving, increasing the feedstock pretreatment efficiency, optimization of stream heat recovery schemes, improvement of hardware design, etc. [ABSTRACT FROM AUTHOR]

This article discusses the examination of energy carriers like hydrogen, natural gas and LPG in regards to their combustion enthalpy with simple school experiments. As a continuation of Part I of the comparative analysis of the energy carriers hydrogen, natural gas and LPG, the measurements and results will be optimized in this publication. The optimization of the measurement results succeeds with more elaborate experimentation material. Therefore, the experiments will be more demonstration experiments rather than student experiments. Due to the use of the combustion calorimeter the results are close to literature values for calorific values. [ABSTRACT FROM AUTHOR]

Regular assessments of events taking place around the globe can be a conduit for the development of new ideas, contributing to the research world. In this study, the authors present a new optimization algorithm named doctor and patient optimization (DPO). DPO is designed by simulating the process of treating patients by a physician. The treatment process has three phases, including vaccination, drug administration, and surgery. The efficiency of the proposed algorithm in solving optimization problems compared to eight other optimization algorithms on a benchmark standard test function with 23 objective functions is been evaluated. The results obtained from this comparison indicate the superiority and quality of DPO in solving optimization problems in various sciences. The proposed algorithm is successfully applied to solve the energy commitment problem for a power system supplied by a multiple energy carriers system. [ABSTRACT FROM AUTHOR]

Due to the necessity of cognizance of demand for the various forms of energy in the agricultural sector in Iran's economy and considering the effects of price liberalization policies on forms of energy, analysis of the main energy carriers' demand is very important. This study used the LA-AIDS approach and ISUR technique to estimate the demand and elasticities for various energy carriers. Also, the welfare effects of increasing energy prices under the 20, 40, 60, 80 and 100% scenarios are evaluated using the compensating variation (CV). The uncompensated and compensated own-price demand elasticities for oil products, electricity and, natural gas carriers were −1.21, −0.85 and −0.55, and −0.98, −0.32 and −0.30, respectively, confirming the demand theory. The cross-price elasticities showed that electricity has substitutability and complementarity relationship with oil products and natural gas, respectively, while the relationship between natural gas and oil products is a substitutability relationship. The income elasticities of energy usages estimated to be 0.64, 1.2 and 1.05. Agricultural producers' welfare would experience a further decrease in oil products and electricity price liberalization, though the welfare impacts of natural gas are trivial. As price elasticity is different in the agricultural sector, price policies, then price liberalization and omitting energy subsidy should be applied based on the elastic or inelastic of energy carriers. The price policies effectiveness on oil products is more than electricity and natural gas. Given the prevalence of consumption and high price elasticities of oil products and pollutants, rising oil prices can reduce their consumption and environmental pollution. [ABSTRACT FROM AUTHOR]

Ammonia is a potential carrier of hydrogen as a zero‐emission fuel. Herein, the effects of calcination and reduction temperatures on the ammonia‐synthesis activity of Ru/La0.5Ce0.5O1.75 are investigated under mild synthesis conditions (≤400 °C, ≤3 MPa), which are the preferred conditions for the storage of hydrogen as an energy source. The highest catalytic activity is obtained after calcination of the support at 700 °C and reduction of the catalyst at 650 °C. Calcination using a higher temperature than that used for reduction results in the induction of a strong metal–support interaction (SMSI) effect. This high‐temperature calcination also provides heat resistance to the support, which prevents sintering of the primary support particles during reduction. Thus, calcination and reduction at temperatures higher than those normally used for the preparation of Ru catalysts provide a novel approach for obtaining supported highly dispersed Ru catalysts exhibiting the SMSI effect and high catalytic activities. [ABSTRACT FROM AUTHOR]

Motivation: The concept of sustained development has been implemented on an increasingly large number of areas of human activity. Energy is one of those areas in the European Union in which this idea is used. Aim: The aim of this study is to assess the energy generation development in Poland and in the other EU countries in the context of sustainable development policy. Results: Considering the highly diverse environmental circumstances, not all countries are likely to meet the ambitious objectives of the EU energy policy in the area of environmental conservation without having to make sacrifices in the socio-economic area. Taking into account the EU's enormous dependence on external supplies of energy carriers, it seems justified to use the concept of sustainable energy security, taking into account the social and technical conditions of individual countries. [ABSTRACT FROM AUTHOR]

Access to energy, including electricity, determines countries’ socio-economic development. The growing demand for electricity translates into environmental problems. Energy is therefore a crucial element of the European Union’s sustainable development strategy. This article aims to present the changes taking place in the electricity market in Poland considering the goals of the energy policy until 2040. This is the basis for the determination of the scale of processes taking place in the Polish energy sector from two perspectives, i.e., the production of electricity considering its level and energy carriers used, and the consumption of electricity in households depending on their location (rural vs. urban areas). The research was conducted at the regional level (NUTS 2 until 2017) in Poland. Secondary data from the Central Statistical Office (GUS) contained in the Local Data Bank were used, along with information from the European Commission and Eurostat websites. Results of the study made it possible to identify areas in which a greater environmental load is observed due to increasing electricity consumption. The coefficient of localization and concentration (by Florence) and the rate of change were applied. These results indicate that, in Poland, it is now the rural areas that have a greater negative environmental impact than urban areas, resulting from differences in unit energy consumption. Compared to the other provinces, rural areas of Podlaskie province had the highest rate of growth in energy consumption in the years 2004–2019, with an annual average of almost 20%.

This study investigates the causal linkages between consumption of energy carriers and value added in the Iranian economic sectors for the period 1974-2013 by using the granger causality test in heterogeneous mixed panels. For this, the panel causality testing approach, the method developed by Emirmahmutoglu and Kose (2011) based on the vector autoregressive (VAR) model and Wald tests with the country specific bootstrap critical values, is applied. This test, accounts cross dependency and heterogeneity among the members of the panel and also, co-integration between variables. Based on the results, the existence of a unidirectional causality relation of oil and gas to value added and the existence of a bidirectional causality relation between electricity and value added in the service sector and the entire sectors is confirmed. In agriculture sector, there is only a causal relation of electricity on value added. In industry sector, the existence of a bidirectional causality relation between gas and electricity with value added and the existence of a unidirectional causality relation of value added to oil is confirmed. In transportation sector, there is a causal relation of gas and electricity to value added and there is a bidirectional causality relation between the oil and the value added. The results can provide important policy recommendations in planning and explaining energy sector policies at the level sector in country.

Electrochemical reduction of CO2 to useful chemicals can change the role of CO2 from harmful waste to a valuable feedstock. Despite a lot of progress in the alkaline electrochemical conversion of CO2 to formate, there is still a lack of potential applications for the generated aqueous formate solution. Here, the general ability of formate to be used as an energy or hydrogen carrier is discussed and compared to well‐known energy storage chemicals. Concepts to employ formate solution as an energy carrier by combining CO2 electrolysis with the reconversion of formate into electricity via a direct formate fuel cell or catalytic decomposition to H2 combined with a proton exchange membrane fuel cell are demonstrated. [ABSTRACT FROM AUTHOR]

In a continuous and swift change of needs in the energy sector, due to multifaceted issues of anthropocene, energy transition has to rely on a suitable energy mix because no unicorn solution is actually capable to give a definitive solution to the problem posed by climate change urgencies. In this paper, the central role of a combustion-based energy system is discussed in relation to its complementarity with Renewable Energy Sources (RES) and their difficulties in ensuring a complete solution to the energy problem. Among others, the availability of critical metals and infrastructures are particularly relevant and may actually endanger the deployment of renewable energy sources. In this panorama, where the exploitation of renewables must be maximized and the effectiveness of energy carriers as storage solution has been proved, combustion plays a primary role. Combustion can be hardly replaced in those sectors where very high temperatures are involved, and in general in the whole hard-to-abate sector that is among the major contributors to CO 2 emission in the atmosphere. From this perspective, combustion systems are a key ingredient in the energy transition but they have to meet three criteria: they have to be efficient, fuel flexible and clean. MILD combustion has been proven to satisfy all these criteria. This paper aims to highlight the emergent features of MILD combustion through simple and immediate examples, looking at its characteristic reactive structure at microscale, its stability as well as its fuel and operational flexibility that enable this combustion process to be an effective support to the energy transition process. [ABSTRACT FROM AUTHOR]

Regular assessments of events taking place around the globe can be a conduit for the development of new ideas, contributing to the research world. In this study, the authors present a new optimization algorithm named doctor and patient optimization (DPO). DPO is designed by simulating the process of treating patients by a physician. The treatment process has three phases, including vaccination, drug administration, and surgery. The efficiency of the proposed algorithm in solving optimization problems compared to eight other optimization algorithms on a benchmark standard test function with 23 objective functions is been evaluated. The results obtained from this comparison indicate the superiority and quality of DPO in solving optimization problems in various sciences. The proposed algorithm is successfully applied to solve the energy commitment problem for a power system supplied by a multiple energy carriers system.

Abstract This paper focuses on the potential use of ammonia as a carbon-free fuel, and covers recent advances in the development of ammonia combustion technology and its underlying chemistry. Fulfilling the COP21 Paris Agreement requires the de-carbonization of energy generation, through utilization of carbon-neutral and overall carbon-free fuels produced from renewable sources. Hydrogen is one of such fuels, which is a potential energy carrier for reducing greenhouse-gas emissions. However, its shipment for long distances and storage for long times present challenges. Ammonia on the other hand, comprises 17.8% of hydrogen by mass and can be produced from renewable hydrogen and nitrogen separated from air. Furthermore, thermal properties of ammonia are similar to those of propane in terms of boiling temperature and condensation pressure, making it attractive as a hydrogen and energy carrier. Ammonia has been produced and utilized for the past 100 years as a fertilizer, chemical raw material, and refrigerant. Ammonia can be used as a fuel but there are several challenges in ammonia combustion, such as low flammability, high NOx emission, and low radiation intensity. Overcoming these challenges requires further research into ammonia flame dynamics and chemistry. This paper discusses recent successful applications of ammonia fuel, in gas turbines, co-fired with pulverize coal, and in industrial furnaces. These applications have been implemented under the Japanese 'Cross-ministerial Strategic Innovation Promotion Program (SIP): Energy Carriers'. In addition, fundamental aspects of ammonia combustion are discussed including characteristics of laminar premixed flames, counterflow twin-flames, and turbulent premixed flames stabilized by a nozzle burner at high pressure. Furthermore, this paper discusses details of the chemistry of ammonia combustion related to NOx production, processes for reducing NOx, and validation of several ammonia oxidation kinetics models. Finally, LES results for a gas-turbine-like swirl-burner are presented, for the purpose of developing low-NOx single-fuelled ammonia gas turbine combustors. [ABSTRACT FROM AUTHOR]