Organic-rich rocks of the Marcellus subgroup in the study area consist of a diverse suite of mudstone lithofacies that were deposited in distinct facies belts. Lithofacies in the succession range in composition from argillaceous to siliceous, calcareous, and carbonaceous mudstone. Heterogeneities in the succession occurs in the form of varying mineralogical composition, slightly bioturbated to highly bioturbated chaotic matrix, organic-rich and organic-lean laminae, scattered fossil shells in the matrix, and fossils acting as lamination planes. Lithofacies were deposited in three facies belts from the proximal to the distal zone of the depositional system. Bedded siliceous mudstone (BSM) facies occur in the proximal facies belt and consists of a high quartz content in addition to clay minerals and pyrite. In the medial part of the facies belt lies the laminated argillaceous mudstone (LAM), bedded calcareous mudstone (BCaM), and bedded carbonaceous mudstone (BCM). The size of detrital m... [more]

Biological methanation as a method of sector coupling between electric and gas grids is expected to be an integral part of the green energy change. Wastewater treatment plants (WWTPs) involving anaerobic digestion (AD) allow existing infrastructure to operate as energy conversion plants, to close carbon cycles and to generate long-term storable energy in the form of biomethane. Therefore, municipal raw sludge and additional organic residuals (co-substrates) are converted into biogas. Hydrogen is added to convert the carbon dioxide in the biogas into methane via biological methanation (BM). In this study, the energy amount that is convertible via BM in municipal digesters in Austria was calculated. The amount of energy, which can be transformed from electric surplus energy into biomethane, was assessed. Operational data from lab-scale digesters were combined with data from 28 Austrian full-scale wastewater treatment plants with AD. They represent 9.2 Mio population equivalents (PE), or... [more]

The study of the mechanical properties and failure behaviors for coal with different bedding structures at various medium strain rates is of great importance for revealing the mechanism of rock burst. In our study, we systematically analyze the uniaxial compressive strength (UCS), acoustic emission (AE) characteristics, failure pattern, and risk of rock burst on coal specimens with two bedding orientations under ranged in strain rates from 10−4 s−1 to 10−2 s−1. The results reflect that and the bedding direction and the strain rates significantly affect the UCS and failure modes of coal specimens. The UCS of coal specimens with loading directions perpendicular to bedding planes (horizontal bedding) increases logarithmically with increasing strain rate while the UCS increases first and then decreases of coal specimens with loading directions parallel to bedding planes (vertical bedding). The AE cumulative energy of the specimens with horizontal bedding is an order of magnitude higher tha... [more]

Supersonic flight for commercial aviation is gaining a renewed interest, especially for business aviation, which demands the reduction of flight times for transcontinental routes. So far, the promise of civil supersonic flight has only been afforded by the Concorde and Tupolev T-144 aircraft. However, little or nothing can be found about the aerodynamics of these aeroshapes, the knowledge of which is extremely interesting to obtain before the development of the next-generation high-speed aircraft. Therefore, the present research effort aimed at filling in the lack of data on a Concorde-like aeroshape by focusing on evaluating the aerodynamics of a complete aircraft configuration under low-speed conditions, close to those of the approach and landing phase. In this framework, the present paper focuses on the CFD study of the longitudinal aerodynamics of a Concorde-like, tailless, delta-ogee wing seamlessly integrated onto a Sears−Haack body fuselage, suitable for civil transportation. Th... [more]

With the recent rising attention and debates on the role of natural gas, especially liquid natural gas, in energy transition, it is critical to have a consistent approach in assessing uncertainties and dynamics in the global gas market during the next two to three decades. There are two objectives of this paper. The first one is to estimate and discuss the impacts of the global liquified natural gas (LNG) trade under a low-carbon scenario using a partial equilibrium model. The second objective is to discuss the role of a structural economic model in empirical analysis and strategy design under a regime shift, such as an energy transition, for the global natural gas market.

Coastal and terrestrial fisheries communities in Europe, often economically marginalised, are likely to face severe impacts as climate change becomes more acute. Although progress on climate mitigation and adaptation from national governments remains slow, local development actions can also address these impacts from the bottom up. In this paper we analyse the Fisheries and Sea Operational Programme 2014−2020 and 36 Local Development Strategies prepared within the framework of this programme for the case of Poland. The strategies, which were prepared by cross-sectoral, area-based partnerships known as Fisheries Local Action Groups, are analysed using a content analysis approach. The aim was to assess the degree to which local stakeholders sought to address the climate challenge. We found that the mitigation of climate impacts and the development of renewable energy did not feature prominently in the analysed documents, suggesting that both central policymakers and local stakeholders in... [more]

Energy safe is mandatory for all isolated IoT tools, such as in long way roads, mountains, or even in smart cities. If increasing the lifetime of these tools, the rentability of the global network loop becomes more efficient. Therefore, this paper presents a new approach for saving energy inside the source nodes by supervising the state of energy inside each source node and calculating the duty cycle factor. The relationship between these parameters is based on an optimization problem formulation. In this respect, the present paper is designed to propose a new approach that deals with increasing the lifetime of the wireless sensor network (WSN)-attached nodes, as fixed in the application. The newly devised design is based on implementing the IEEE 802.15.4 standard beacon-enabled mode, involving a cluster tree topology. Accordingly, every subgroup is allotted to apply a specifically different duty cycle, depending on the battery’s remaining energy level, which contributes to creating a... [more]

Research on corona discharge, shared by physics, chemistry and electrical engineering, has not arrested yet. As a dissipative process, the development of corona increases the resistive losses of transmission lines and enhances the line capacitance locally. Introducing additional losses and propagation delay, along the line, non-linearity and non-uniformity of the line parameters; therefore, corona should not be neglected. The present work is meant to provide the reader with comprehensive information on the corona macroscopic phenomenology and development, referring to the most relevant contributions in the literature on this subject. The models proposed in the literature for the simulation of the corona development are reviewed in detail, and sensitivity curves are provided to highlight their dependence on the input parameters.

A residential cogeneration system (CGS) is highlighted because of its efficient energy usage on both the supplier and consumer sides. It generates electricity and heat simultaneously; however, there is insufficient information on the efficiency according to the condition of usage. In this study, we analysed the performance data measured by the home energy management system (HEMS) and the lifestyle data of residents in a condominium of 356 flats where fuel cell CGS was installed in each flat. The electricity generated by CGS contributed to an approximately 12% reduction in primary energy consumption and CO2 emission, and the rate of generation by the CGS in the electric power demand (i.e., contribution rate) was approximately 38%. The electricity generation was mainly affected by the use of electricity up to 4 MWh/household/year. Gas or water use also impacted electric power generation, with water use as the primary factor affecting the contribution rate. Electric power generation chang... [more]

Electrifying public bus transportation is a critical step in reaching net-zero goals. In this paper, the focus is on the problem of optimal scheduling of an electric bus (EB) fleet to cover a public transport timetable. The problem is modelled using a mixed integer program (MIP) in which the charging time of an EB is pertinent to the battery’s state-of-charge level. To be able to solve large problem instances corresponding to real-world applications of the model, a metaheuristic approach is investigated. To be more precise, a greedy randomized adaptive search procedure (GRASP) algorithm is developed and its performance is evaluated against optimal solutions acquired using the MIP. The GRASP algorithm is used for case studies on several public transport systems having various properties and sizes. The analysis focuses on the relation between EB ranges (battery capacity) and required charging rates (in kW) on the size of the fleet needed to cover a public transport timetable. The results... [more]

Erosion caused by solid particles in a pipeline is one of the main problems endangering the safety production of the oil and gas industry, which may lead the equipment to malfunction or even fail. However, most of the previous studies focused on the standard elbow, and the erosion law of right-angle elbow and blind tee is rarely reported in the literature. This work aims to investigate the erosion law of different pipeline structures including 90° elbow, right-angle pipe, and tee pipe based on the production characteristics and engineering parameters of the gas field. An integrated CFD-DPM method is established including a realizable k-ε turbulence model, discrete phase model, and erosion rate prediction model. The accuracy of the model is evaluated by a series of experimental data of flow conditions of our previous work. Further, the erosion rate, pressure distributions, and particle trajectories in 90° elbow, right-angle pipe, and tee pipe under different flow velocities, particle ma... [more]

The micro direct methanol fuel cell (μDMFC) has attracted more and more attention in the field of new energy due to its simple structure, easy operation, and eco-friendly byproducts. In a μDMFC’s structure, the current collector plays an essential role in collecting the conduction current, and the rational distribution of gas and water. The choice of its material and flow fields would significantly impact the μDMFC’s performance. To this end, four different types of cathode current collector were prepared in this study. The materials selected were stainless steel (SS) and foam stainless steel (FSS), with the flow fields of hole-type and grid-type. The performance of the μDMFC with different types of cathode current collector was investigated by using polarization curves, electrochemical impedance spectroscopy (EIS), and discharging. The experimental results show that the maximum power density of μDMFC of the hole-type FSS cathode current collector is 49.53 mW/cm2 at 70 °C in the methan... [more]

The state-of-the-art provides data-driven and knowledge-driven diagnostic methods. Each category has its strengths and shortcomings. The knowledge-driven methods rely mainly on expert knowledge and resemble the diagnostic thinking of domain experts with a high capacity in the reasoning of uncertainties, diagnostics of different fault severities, and understandability. However, these methods involve higher and more time-consuming effort; they require a deep understanding of the causal relationships between faults and symptoms; and there is still a lack of automatic approaches to improving the efficiency. The data-driven methods rely on similarities and patterns, and they are very sensitive to changes of patterns and have more accuracy than the knowledge-driven methods, but they require massive data for training, cannot inform about the reason behind the result, and represent black boxes with low understandability. The research problem is thus the combination of knowledge-driven and data... [more]

The proposal of new technologies capable of producing electrical energy from renewable sources has driven research into seas and oceans. Research finds this field very promising in the future of renewable energies, especially in areas where there are specific climatic and morphological characteristics to exploit large amounts of energy from the sea. In general, this kind of energy is referred to as six energy resources: waves, tidal range, tidal current, ocean current, ocean thermal energy conversion, and saline gradient. This review has the aim to list several wave-energy converter power plants and to analyze their years of operation. In this way, a focus is created to understand how many wave-energy converter plants work on average and whether it is indeed an established technology.

Interest in alternative and renewable energy sources has risen significantly in recent years. Biogas is a prime example of a promising, alternative fuel that might be a possible replacement for fossil fuels. It is a mixture consisting mainly of CH4 and CO2 with various additions. Biogas is easily storable and as such is a more reliable and stable source of energy than solar and wind sources, which suffer from unreliability due to their dependence on weather conditions. In this paper, the authors report experimental results of detonation of a biogas-oxygen mixture. The composition of the biogas was 70% CH4 + 30% CO2 and the experiments were carried out for a range of equivalence ratios (Φ = 0.5 ÷ 1.5) and initial pressures (0.6 ÷ 1.6 bar). The aim of the research was to analyze the cellular structure of detonation. The soot foil technique was used to determine the width of the detonation cells (λ). The conducted experiments and subsequent analysis of the detonation cell size confirm tha... [more]

Stringent environmental regulations and efforts to improve the shipping operations sustainability have resulted in designing and employing more complex configurations for the ship power plants systems and the implementation of digitalised functionalities. Due to these systems complexity, critical situations arising from the components and subsystem failures, which may lead to accidents, require timely detection and mitigation. This study aims at enhancing the safety of ship complex systems and their operation by developing the concept of an integrated monitoring safety system that employs existing safety models and data fusion from shipboard sensors. Detailed Fault Trees that model the blackout top event, representing the sailing modes of a cruise ship and the operating modes of its plant, are employed. Shipboard sensors’ measurements acquired by the cruise ship alarm and monitoring system are integrated with these Fault Trees to account for the acquired shipboard information on the in... [more]

The continued use of fossil fuels is contributing to severe environmental pollution and the establishment of an abnormal climate; consequently, alternative renewable energy sources are being actively investigated worldwide. Further, following global trends, numerous countermeasures aimed at improving carbon neutrality, promoting sustainable agriculture, and reducing fossil fuel dependence are being implemented in the Republic of Korea. Therefore, this study was conducted to investigate the application of renewable energies for greenhouse heating in the Republic of Korea. Three hybrid systems, numbered 1−3, were constructed using a pellet boiler, hydrothermal heat pump, and solar heat collection system, respectively. Thereafter, the heating performance, combined heat efficiency, energy consumption per temperature lifting, and energy cost per temperature lifting of the systems were compared. The combined thermal efficiency results showed no significant differences. However, in terms of e... [more]

Hydrothermal liquefaction can directly and efficiently convert wet biomass into biocrude with a high heating value. We developed a continuous hydrothermal liquefaction model via Aspen Plus to explore the effects of moisture content of Chlorella, reaction pressure and temperature on thermodynamic equilibrium yields, and energy recoveries of biocrude. We also compared the simulated biocrude yield and energy recoveries with experiment values in literature. Furthermore, vertical and horizontal transportation characteristics of insoluble solids in Chlorella were analyzed to determine the critical diameters that could avoid the plugging of the reactor at different flow rates. The results showed that the optimum moisture content, reaction pressure, and reaction temperature were 70−90 wt%, 20 MPa, and 250−350 °C, respectively. At a thermodynamic equilibrium state, the yield and the energy recovery of biocrude could be higher than 56 wt% and 96%, respectively. When the capacity of the hydrother... [more]

Wind turbine pitch system condition monitoring is an active area of research, and this paper investigates the use of the Isolation Forest Machine Learning model and Supervisory Control and Data Acquisition system data for this task. This paper examines two case studies, turbines with hydraulic or electric pitch systems, and uses an Isolation Forest to predict failure ahead of time. This novel technique compared several models per turbine, each trained on a different number of months of data. An anomaly proportion for three different time-series window lengths was compared, to observe trends and peaks before failure. The two cases were compared, and it was found that this technique could detect abnormal activity roughly 12 to 18 months before failure for both the hydraulic and electric pitch systems for all unhealthy turbines, and a trend upwards in anomalies could be found in the immediate run up to failure. These peaks in anomalous behaviour could indicate a future failure and this wo... [more]

Within China’s renewable energy industry, the importance of the solar photovoltaic industry has been increasingly recognized. Many Chinese provinces have adopted various measures to develop the solar photovoltaic industry. This study used the diamond model and the analytic hierarchy process to clarify the relative importance of the determinants of the development of the solar photovoltaic industry. A total of 22 determinants in six categories (i.e., factor condition; demand condition; firm strategy, structure, and rivalry; related and support industries; government; and chance) were analyzed. The results show that besides factor condition, demand condition and firm strategy, structure, and rivalry have also had a strong influence on the development of China’s photovoltaic industry. The findings also indicate that some traditional factors, such as labor costs and acquiring land, are very important to the development of the solar photovoltaic industry. The relative importance of the dete... [more]

Diagnosing faults in electric vehicles (EVs) is a great challenge. The purpose of this paper is to demonstrate the detection of faults in an electromechanical conversion chain for conventional or autonomous EVs. The information and data coming from different sensors make it possible for EVs to recover a series of information including currents, voltages, speeds, and so on. This information is processed to detect any faults in the electromechanical conversion chain. The novelty of this study is to develop an architecture for a fault diagnosis model by means of the feature extraction technique. In this regard, the long short-term memory (LSTM) approach for the fault diagnosis is proposed. This approach has been tested for an EV prototype in practice, is superior in accuracy over other fault diagnosis techniques, and is based on machine learning. An EV in an urban context is modeled, and then the fault diagnosis approach is applied based on deep learning architectures. The EV and the faul... [more]

Mosques are quite different from other building types in terms of occupant type and usage schedule. For this reason, they should be evaluated differently from other building types in terms of thermal comfort and energy consumption. It is difficult and probably not even necessary to create homogeneous thermal comfort in mosques’ entire usage area, which has large volumes and various areas for different activities. Nevertheless, energy consumption should be at a minimum level. In order to ensure that mosques are minimally affected by outdoor climatic changes, the improvement of the properties of the building envelope should have the highest priority. These optimal properties of the building envelope have to be in line with thermal comfort in mosques. The proposed method will be a guide for designers and occupants in the design process of new mosques or the use of existing mosques. The effect of the thermal properties of the building envelope on energy consumption was investigated to ensu... [more]

Energy storage technologies can reduce grid fluctuations through peak shaving and valley filling and effectively solve the problems of renewable energy storage and consumption. The application of energy storage technologies is aimed at storing energy and supplying energy when needed according to the storage requirements. The existing research focuses on ranking technologies and selecting the best technologies, while ignoring storage requirements. Here, we propose a multi-criteria decision-making (MCDM) framework for selecting a suitable technology based on certain storage requirements. Specifically, we consider nine criteria in four aspects: technological, economic, environmental, and social. The interval number, crisp number, and linguist terms can be transformed into a probabilistic dual hesitant fuzzy set (PDHFS) through the transformation and fusion method we proposed, and a suitable technology can be selected through distance measurements. Subsequently, the proposed method is appl... [more]

The occurrence of voltage violations is a major deterrent for absorbing more rooftop solar power into smart Low-Voltage Distribution Grids (LVDGs). Recent studies have focused on decentralized control methods to solve this problem due to the high computational time in performing load flows in centralized control techniques. To address this issue, a novel sensitivity matrix was developed to estimate the voltages of the network by replacing load flow simulations. In this paper, a Centralized Active, Reactive Power Management System (CARPMS) is proposed to optimally utilize the reactive power capability of smart Photovoltaic (PV) inverters with minimal active power curtailment to mitigate the voltage violation problem. The developed sensitivity matrix is able to reduce the time consumed by 55.1% compared to load flow simulations, enabling near-real-time control optimization. Given the large solution space of power systems, a novel two-stage optimization is proposed, where the solution spa... [more]

Fleet electrification is one of the measures proposed for achieving climate neutrality in the coming years. The replacement of internal combustion engine vehicles with electric vehicles has a positive impact on carbon emission reduction in some countries. However, in countries highly dependent on fossil fuels, such a possibility requires examination with respect to the means of electricity generation and fuel mix used in their power systems. One such country is Poland, selected as an example of an economy strongly dependent on fossil fuels. The main objective of this paper is to investigate the impact of fleet electrification of an individual company located in Poland on the reduction of carbon emissions. The concept and calculations are based on historical data on the single-year mileage and fuel consumption of 619 cars used by this company. Even though the Polish power system is based on fossil fuels, fleet electrification could contribute to a reduction in carbon emissions of 24%. T... [more]