The number of electric vehicles (EV) on the roads, as well as the share of EVs in use, will inevitably increase in coming decades. This creates a number of problems. A large EV fleet is a significant additional load in the power system that is impossible to accurately predict. Another related problem is the limited distribution network capacity, which is not ready for the additional load from the widespread EV infrastructure. There is a need for an EV charging coordination algorithm capable of fulfilling the charging EV needs, while using as low demanded power as possible and using the lowest power values in each EV charging profile. We propose an EV coordinating algorithm that is capable of ensuring that all connected EVs in the considered parking lot will be charged at the user-defined departure time. The algorithm also controls the charging/discharging power of every connected EV in such a way that the parking lot as a whole will use minimal possible peak power while minimizing the... [more]

The anomalous enrichment of the rare earth elements and yttrium (REY), U, Mo, As, Se, and V in the coal-bearing intervals intercalated within the carbonate successions in South China has attracted much attention due to the highly promising recovery potential for these elements. This study investigates the mineralogical and geochemical characteristics of the late Permian coal-bearing intervals (layers A−F) intercalated in marine carbonate strata in the Xian’an Coalfield in Guangxi Province to elucidate the mode of occurrence and enrichment process of highly elevated elements. There are two mineralogical assemblages, including quartz-albite-kaolinite-carbonates assemblage in layers D−F and quartz-illite-kaolinite-carbonates assemblage in layers A−C. Compared to the upper continental crust composition (UCC), the REY, U, Mo, As, Se, and V are predominantly enriched in layers A and B, of which layer A displays the REY−V−Se−As assemblage while layer B shows the Mo−U−V assemblage. The elevate... [more]

This paper investigates the characterization of an electric double-layer capacitor (EDLC). In this study, the 300 F and 400 F EDLC supercapacitors are connected in a circuit in a laboratory experiment to produce their charge/discharge profiles at a constant current. The acquired charge/discharge profiles were used to determine the mathematical parameters of the EDLCs using the “Faranda model”, or “two-branch model”, of the EDLC. The parameters extracted from the equivalent circuit model were then used as inputs to a designed Python/MATLAB/Simulink (PMS)-hybrid model of an EDLC. This was simulated to obtain charge/discharge profiles. The resulting experimental- and simulated-charge/discharge profiles of the EDLCs were compared with each other, by superimposing their profiles to determine the accuracy of the PMS model. The PMS model was found to be very accurate. The innovation of this work lies in modeling a supercapacitor, mostly in the Python programming language in combination with a... [more]

Aim: In this paper, we analyze the potential of various digital tools such as gamification-based applications or digital currencies in enabling the social engagement in climate change mitigation processes by encouraging pro-environmental behaviors. Therefore, as a result of this study, we aim to develop a conceptual framework for a green digital tool, dedicated to cities seeking to shape their resilience by supporting bottom-up initiatives and encouraging residents to join the effort through educational interventions. Methods: The study was divided into four steps using a variety of methodological approaches, including a review of the SLR literature, analysis of the successes and failures of existing solutions, and qualitative workshops with stakeholders. Findings: The conceptual basis of the proposed solution has been developed based on the existing knowledge on pro-environmental nudging and lessons learnt from existing solutions. Value/originality: The developed conceptual framework... [more]

The powertrain of a fuel cell vehicle typically consists of two energy sources: a proton electrolyte membrane fuel cell (PEMFC) stack and a battery package. In this paper, multi-dimensional dynamic programming (MDDP) is used to solve the energy management strategy (EMS) of fuel cell hybrid powertrain. This study built a fuel cell hybrid powertrain model, in which the battery model is built based on the Thevenin equivalent circuit. In order to improve the calculating efficiency and maintain the accuracy of the algorithm, the state variables in each stage are divided into primary and secondary. In the reverse solution process, the corresponding relationship between the multi state variables grid and the optimal cumulative function has been changed from three-dimensional to two-dimensional. The EMS based on MDDP is applied to component sizing of a commercial vehicle. Simulations were conducted using MATLAB under the C-WTVC working condition. By analyzing the fuel economy and system durabi... [more]

A mixture of lanthanum strontium cobalt ferrite (LSCF) and nickel oxide (NiO) makes for a desirable cathode material for an IT-SOFC due to its excellent oxygen reduction capability. This study investigates the effect of NiO addition into LSCF cathode on its physical and electrochemical properties. To optimise the amount of NiO addition, both electrochemical impedance spectra and bode phase were used to examine various weight ratios of nickel oxide and LSCF cathode. Brunauer-Emmett-Teller (BET) and thermal analyses validated the electrochemical observation that the LSCF:NiO ratio yields sensible oxygen reduction reaction and stoichiometric findings. Initial characterisation, comprising of phase and bonding analyses, indicated that LSCF-NiO was successfully synthesised at 800 °C using an improved modified sol gel technique. The addition of 5% nickel oxide to LSCF results in the lowest area specific resistance (ASR) value overall. The Bode phase implies that the addition of 5% nickel oxid... [more]

The fast charging process of high-pressure gas storage cylinders is accompanied by high temperature rise, which potentially induces the failure of solid materials inside the cylinders and the underfilling of the cylinders. A two-dimensional (2D) axisymmetric model simulated the charging process of hydrogen storage cylinders with a rated working pressure of 35 MPa and a volume of 150 L. During filling, the highest temperature rise inside the cylinder occurs at the bottom part of the cylinder, and the state of charge (SOC) is 46.4% after filling. This temperature rise can be reduced by precooling the injected hydrogen, and the highest SOC can reach 95.7% after injection. The SOC in the cylinder gradually increases with a decrease in the temperature of the hydrogen injection. The maximum SOC increase is 49.3%. For safety and the SOC exceeding 90%, the hydrogen gas should be precooled to below −10 °C, and the SOC could achieve more than 90.3%. The internal structure of the hydrogen cylinde... [more]

The aim of the study was to estimate the effectiveness of ultrasonic coagulation aiding. The effect of ultrasound exposure alone and associated systems (ultrasound exposure/coagulant) on the contamination of natural water was examined. The evaluation of the test results was based on changes in indicators, such as TOC, color, turbidity, and electrokinetic potential. Three different coagulants were used in the tests of associated systems. The tests included basic processes related to volumetric coagulation, such as agitation, flocculation, and sedimentation. Sonication of water samples was carried out at a constant frequency of 22 kHz, variable vibration amplitude of 8−16 μm, and an exposure time of 1−5 min. The most efficient removal of organic contaminants from the water tested was achieved at a maximum amplitude of A = 16 μm, with effectiveness reaching 29% (TOC). In the tests of the associated systems, the effect of ultrasound exposure on the removal of water turbidity (an increase i... [more]

This book contains the successful submissions [...]

Energy security is a multidimensional and multifaceted concept, therefore defining it is a complex problem. It requires the consideration of a wide set of factors from the fields of economics, geology, ecology and geopolitics, all of which have an influence on energy security or the lack thereof. The article focuses on natural gas, which is a very specific fuel in the European context. It is the most “politicized” source of energy, as a consequence of its growing importance as a transition fuel in the energy transformation process. In order to identify dependencies between variables on the gas market and analyze their impact on it (in particular on underground storage), the authors chose a set of variables and built a Bayesian network. The network is an effective and flexible tool that allows analysis of the relationships between the variables that build them and model their values based on evidence. The article presents two stages of work with the Bayesian network. In the first one, a... [more]

With the increasing proportion of wind turbines in power grids, they are required to have capabilities of active and efficient virtual inertial response to maintain grid frequency stability. However, the virtual inertial control methods currently used in doubly-fed induction generator (DFIG) units suffer from a secondary frequency drop (SFD) problem. Although the SFD can be inhibited by reducing the active power support strength of the DFIG units during inertia response, it will undoubtedly weaken the virtual inertia of the units. Therefore, how to eliminate the SFD while increasing the virtual inertia of the units is a worthy issue for studying. To solve this issue, a wind-storage combined virtual inertial control system based on quantization and regulation decoupling of active power increments is proposed in this paper. First, by setting the parameters of a proportional−differential (P-D) algorithm, the total active power increments required for virtual inertial response are quantifi... [more]

Electric motors are utilitarian devices of great potential as they can limit the amount of pollution by drastically reducing the release of harmful gases. The implementation of the right type of advanced materials plays a vital role in the amelioration of modern automobiles while maintaining and/or improving the performance and efficiency of the electric motor. The use of lightweight materials could result in a better-performing vehicle that can be much less heavy. The replacement of regular cast iron, steel, and aluminum with lightweight materials such as fiber-reinforced polymer, carbon fiber, and polymer composites can reduce the weight of the motor without impacting its performance and improve its energy-saving capacity. This paper explores a way to reduce motor weight by employing a PA6GF30 30% glass fiber-reinforced polymer casing to reduce the weight of the motor while making cooling system modifications. This material was applied to the motor casing, which resulted in a signifi... [more]

Rapidly declining costs of renewable energy technologies have made solar and wind the cheapest sources of energy in many parts of the world. This has been seen primarily as enabling the rapid decarbonization of the electricity sector, but low-cost, low-carbon energy can have a great secondary impact by reducing the costs of energy-intensive decarbonization efforts in other areas. In this study, we consider, by way of an exemplary carbon capture and utilization cycle based on mature technologies, the energy requirements of the “industrial carbon cycle”, an emerging paradigm in which industrial CO2 emissions are captured and reprocessed into chemicals and fuels, and we assess the impact of declining renewable energy costs on overall economics of these processes. In our exemplary process, CO2 is captured from a cement production facility via an amine scrubbing process and combined with hydrogen produced by a solar-powered polymer electrolyte membrane, using electrolysis to produce methano... [more]

Recently, more and more new oil fields entering commercial production are complicated by the content of high-viscosity products, which are located at relatively shallow depths. For the rational development of such fields, a network of horizontal wells is used. A special feature of these objects is a weakly cemented reservoir, which leads to significant sand occurrence during well operation. At the same time, the removal of mechanical impurities cannot be avoided even when using complex measures, including the use of various filters. There are quite a few methods describing the behavior of mechanical impurities in gas−liquid flows. The purpose of the work was to analyze the removal of mechanical impurity particles from horizontal wells with high-viscosity oil. A model of a typical well in the OLGA software was created, and data on the types of particle removal were obtained. As a result of calculations, the quality of removal for different diameters of mechanical impurities was determin... [more]

Spraying flue gas desulfurization wastewater into flue ducts is an emerging technology that is receiving extensive attention in thermal power plants. In order to study the evaporative performance of wastewater-atomizing droplets under variable working conditions, a combined Euler−Lagrange model was developed to demonstrate the thermal behavior of FGD wastewater spray evaporation in flue gas. The effects of several control factors under various operating conditions were numerically determined and validated against experimental data. Due to the complicated parameters and various other conditions, a least-square support vector machine (LSSVM) model relying on numerical results was used to anticipate the evaporation rate of the droplets. We prove that the LSSVM model has high prediction accuracy for the evaporation rate at different cross-sections of flue under a different operating situation. The conclusion is that for the sake of improving the quality of evaporation, the spacing between... [more]

An autonomous microgrid is often formed by incorporating distributed generators into the distribution system. However, distributed generators have less inertia compared to traditional synchronous generators, and can cause the system frequency to become unstable. Additionally, as more clusters are integrated into the distribution microgrid, frequency instability increases. To resolve frequency instability in the microgrid cluster, this study proposes a supercapacitor control approach. The microgrid consists of several clusters which integrate wind power generators, solar PV, STP, fuel cells, aqua electrolyzers, and diesel generators. Initially, a small signal model is developed to facilitate the control design. A fractional-order supercapacitor controller is augmented with the developed small-signal model to stabilize the frequency of the microgrid. Furthermore, the controller parameters are optimized to guarantee robust controller performance. The proposed fractional-order supercapacit... [more]

A significant portion of the Indian population lives in villages, some of which are located in grid-disconnected remote areas. The supply of electricity to these villages is not feasible or cost-effective, but an autonomous integrated hybrid renewable energy system (IHRES) could be a viable alternative. Hence, this study proposed using available renewable energy resources in the study area to provide electricity and freshwater access for five un-electrified grid-disconnected villages in the Odisha state of India. This study concentrated on three different kinds of battery technologies such as lithium-ion (Li-Ion), nickel-iron (Ni-Fe), and lead-acid (LA) along with a diesel generator to maintain an uninterrupted power supply. Six different configurations with two dispatch strategies such as load following (LF) and cycle charging (CC) were modelled using nine metaheuristic algorithms to achieve an optimally configured IHRES in the MATLAB© environment. Initially, these six configurations... [more]

Owing to the stringent regulations on pollutant emissions that are imposed by the International Maritime Organization and increasing fuel prices, there has been significant research on developing cleaner fuels and novel propulsion systems. This study presents a techno-economical and risk assessment method for evaluating alternative propulsion technologies and cleaner fuels as substitutes for heavy fuel oil and two-stroke diesel engines in marine transportation. This analysis was carried out for two different journeys. Accordingly, we evaluated the economic benefits of using an enhanced intercooler/reheat combined gas and steam cycle or simple and intercooler/reheat combined gas and steam cycles that were fueled by marine diesel oil or liquified natural gas instead of a two-stroke diesel engine that was fueled by MDO as the propulsion system in a large container ship, considering different shipping routes. The results highlighted the advantages of implementing the simple, intercooler/re... [more]

Ship emissions are one of the main sources of air pollution in port cities. The prosperous maritime trade has brought great harm to the air quality of port cities while promoting the development of the world economy. During the berthing process, ship auxiliary machines emit a large amount of air pollutants, which have a great impact on air quality and public health. Alternative marine fuels are being studied and used frequently to reduce ship emissions. This research was carried out to investigate the gaseous and particles emission characteristics of a marine diesel engine during the application of experimental biodiesel fuels. To study the influence of mixed fuels on engine performance, measurements were made at different engine loads and speeds. Different diesel fuels were tested using various ratios between biodiesel and BD0 (ultra-low sulfur diesel) of 0%, 10%, 30%, 50%, 70%, 90%, and 100%. The results indicated the use of biodiesel has little influence on the combustion performanc... [more]

The last three years have been a period of many challenges related to the dynamically changing conditions of the economic environment. Among these many changes, some of the most important for the further functioning of private and public entities are those related to the instability of the energy market. Rapidly rising energy prices increase the costs of implementing public tasks. They also greatly increase the search for innovative, energy-saving and environmentally friendly ways of performing municipal tasks. The main aim of the article is to present the concept of a smart village as an instrument for the implementation of public tasks in rural areas. The theoretical basis of the smart village concept is the basic point of reference. The implementation of the assumptions of the smart village concept in Poland gives municipalities the possibility of an innovative approach to the implementation of local public services. In addition, examples of good practices implemented by rural local... [more]

The reasonable and efficient use of the abundant biomass resources in rural areas has not been realized. Therefore, the concept of a combined cooling, heating, and power (CCHP) microgrid system, considering biomass pyrolysis and gasification, has been developed by researchers. A biomass gasification device can fully use biomass resources and can play a role in absorbing wind energy. Meanwhile, in order to minimize the operating cost of each micropower supply unit, as well as the environmental pollution costs, researchers have also established an optimal scheduling model for CCHP microgrids, which uses the sparrow search algorithm. In this paper, we have improved upon the traditional sparrow algorithm to solve the problems of its uneven population distribution, poor global search ability, and the risk of falling into local optima, through the development of the random walk sparrow search algorithm (RSSA). First, a sinusoidal chaotic map is used to generate the early-generation sparrow p... [more]

This paper focuses on possible power generation by micro-hydro turbines integrated into lowland wastewater systems, which convert the potential energy of effluents in pipes into electric power. While other European countries have widely invested in this technology, Lithuania and other Baltic countries are still behind with their potential development rate. A search for potential micro-hydro sites was carried out, and a methodology for assessing water resources for an ungauged wastewater network is proposed herein. Particularities of wastewater flow patterns are briefly reviewed, and turbine operational constraints are analyzed. The hydro turbines available on the market to be installed in wastewater systems that meet lowland conditions are discussed. Available tools on the hydropower market to conduct a preliminary assessment of potential sites for urban water networks are considered. Multicriteria analysis is performed to select optimal projects by assessing the relevant economic, tec... [more]

Current electric utilities must achieve reliability enhancement of considerable distribution feeders with an economical budget. Thus, optimal preventive maintenance planning is required to balance the benefits and costs of maintenance programs. In this research, the proposed method determines the time-varying failure rate of each feeder to evaluate the likelihood of future interruptions. Meanwhile, the consequences of feeder interruptions are estimated using interruption energy rates, customer-minutes of interruption, and total kVA of service areas. Then, the risk is assessed and later treated as an opportunity for mitigating the customer interruption costs by planned preventive maintenance tasks. Subsequently, cooperative game theory is exploited in the proposed method to locate a decent balance between the benefits of reliability enhancement and the costs required for preventive maintenance programs. The effectiveness of the proposed method is illustrated through case studies of larg... [more]

In order to find the causes of statistical line loss abnormalities and propose better loss reduction strategies, it is necessary to improve the accuracy of theoretical line loss calculations. Since Distributed Generation (DG) access to the distribution network causes variability of power flow in the distribution network within a short period, the error of the traditional line loss calculation method increases. For the line loss calculation of medium-voltage distribution networks containing DGs with high-density collection data, a continuous line loss calculation method for the distribution network was proposed, aiming at improving the accuracy compared with the traditional line loss calculation method. The proposed method makes full use of the high-density collection data on the dispatch side and DG side, distributing the supply power to each load node by power to calculate real-time power flow, thus obtaining a more credible line loss value. The effectiveness and accuracy of the propo... [more]

The European Union takes significant steps to support the development of the electric sector of the automotive market. This is confirmed by the signed declaration in Glasgow, which leads to a ban on the sale of cars with combustion engines from 2035. This document changes the car industry and makes it dependent on electricity production. The problem identified in this article is the actual impact of implemented solutions concerning the type of engine in cars offered for sale in Czechia, Germany, and Poland. Therefore, the aim of this scientific paper is car engines’ multilevel comparative analysis. The aim of the article is accompanied by a research question: are electric vehicles less harmful to the natural environment? The paper compares cars of the same producer, class, and type with petrol, diesel, hybrid (petrol-electric), and electric engines in terms of the environmental impact. The research method is a comparative SUV analysis supported by the comparison of selected countries’... [more]