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Energies, Volume 14, Issue 19 (October-1 2021) – 436 articles

Cover Story (view full-size image): Digital transformation of the modern era enables new approaches for efficient petroleum production, with numerous possible applications. Artificial intelligence may be developed and used to implement digital twin technology in the power supply of oil production enterprises. The study of control loops allows the energy efficient production of hydrocarbons, taking into account reliability, safety, and the eco and energy efficiency of power units. The choice of architecture for building energy systems and their justification plus the integration of automated control algorithms for an electric drive and an automated process control system together with a power supply management system make it possible to prolong the lifecycle of electric equipment at oil and gas enterprises. View this paper
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16 pages, 3422 KiB  
Article
When, What and How to Teach about Electric Mobility? An Innovative Teaching Concept for All Stages of Education: Lessons from Poland
by Katarzyna Turoń, Andrzej Kubik and Feng Chen
Energies 2021, 14(19), 6440; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196440 - 08 Oct 2021
Cited by 21 | Viewed by 2663
Abstract
The implementation of new mobility solutions based on electric vehicles such as electric cars, electric scooters, and electric bikes, in urban transport systems, may bring several advantages for society, from environmental and economic benefits to improved quality of life. Nevertheless, we witness a [...] Read more.
The implementation of new mobility solutions based on electric vehicles such as electric cars, electric scooters, and electric bikes, in urban transport systems, may bring several advantages for society, from environmental and economic benefits to improved quality of life. Nevertheless, we witness a scarcity of education and promotion that supports electric mobility, which can lead to social barriers due to the lack of knowledge. Consequently, people may be discouraged from using new transport technologies. The article focuses on electric mobility issues and present the original concept of electric mobility education. The goal of the work is to identify appropriate educational methods, useful during teaching about electric mobility at different levels of education. The concept focuses on education from primary school to long-life learning. Presented pedagogical concept is based on the three main pillars of pedagogy as diagnosis, forecasting, and content developing. It was developed based on expert research and diagnosed challenges and education gaps during teaching about electric mobility. The concept includes many techniques of education, from the classic methods as lectures and working with books to new educational solutions as e-learning. The original concept of electric mobility education creates new opportunities to promote electric mobility and support the process of creating new services in the electric mobility market. Full article
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11 pages, 1941 KiB  
Article
Emission Characteristics of Pollution Gases from the Combustion of Food Waste
by Haili Liu, Xu Zhang and Qingchao Hong
Energies 2021, 14(19), 6439; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196439 - 08 Oct 2021
Cited by 4 | Viewed by 1740
Abstract
The emission characteristics of pollution gases produced via the combustion of food waste were studied through a laboratory-scale electrically heated tube furnace. The results showed that the pollution gases generated from the combustion of food waste were CO, H2 and NOx [...] Read more.
The emission characteristics of pollution gases produced via the combustion of food waste were studied through a laboratory-scale electrically heated tube furnace. The results showed that the pollution gases generated from the combustion of food waste were CO, H2 and NOx. Each emission curve of CO had a peak. When the combustion temperature rose from 400 °C to 1000 °C, the peak first increased (from 400 °C to 700 °C) and then decreased (from 800 °C to 1000 °C). However, the burnout time shortened with the increase in temperature. Therefore, food waste should be combusted at a higher temperature than 700 °C from the perspective of reducing CO emissions. The emissions of H2 were similar to those of CO. In other words, if CO emissions increased, H2 emissions also increased in the same temperature range. Some NOx emission curves had two peaks (the combustion of cooked rice at 1000 °C; the combustion of vegetable leaves in the temperature range of 600 °C to 1000 °C). The higher the combustion temperature, the higher the second NOx emission peak. NOx emissions from the combustion of cooked rice were greater in the temperature range of 400 °C to 500 °C, whereas for vegetable leaves, that temperature range was from 600 °C to 700 °C. Hence, from the viewpoint of reducing pollution gases, food waste should be combusted at a higher temperature than 700 °C. Full article
(This article belongs to the Special Issue Combustion and Energy Conversion under Small Scales)
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22 pages, 2236 KiB  
Article
Dynamic Spillovers and Asymmetric Spillover Effect between the Carbon Emission Trading Market, Fossil Energy Market, and New Energy Stock Market in China
by Dan Nie, Yanbin Li and Xiyu Li
Energies 2021, 14(19), 6438; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196438 - 08 Oct 2021
Cited by 24 | Viewed by 2579
Abstract
In 2020, China proposed the goal of achieving carbon emission peaks by 2030 and carbon neutrality by 2060. For China, whose energy consumption structure has long been dominated by fossil energy, carbon trading and new energy are crucial for the realization of the [...] Read more.
In 2020, China proposed the goal of achieving carbon emission peaks by 2030 and carbon neutrality by 2060. For China, whose energy consumption structure has long been dominated by fossil energy, carbon trading and new energy are crucial for the realization of the emission target. By establishing a connectedness network model, this paper studies the static and dynamic spillovers between the Hubei carbon trading market, new energy stock market, crude oil market, coal market, and natural gas market in China, and draws the following conclusions: (1) the static spillover index of the carbon–energy–stock system is 3.57% and the dynamic spillover index fluctuates between 7.67% and 22.62%, indicating that the spillover effect of the system is low; (2) for the whole system, whether from a static or dynamic perspective, the carbon market always plays the role of net information receiver, while new energy is the net information transmitter; (3) the new energy stock market and the coal market always act as net information transmitters to the carbon market; and (4) the spillover effect of the system is asymmetric, wherein the system is more sensitive to negative information about price returns, and this asymmetry is much greater when the system is active. Full article
(This article belongs to the Section C: Energy Economics and Policy)
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16 pages, 2150 KiB  
Article
Time-Dependent Upper Limits to the Performance of Large Wind Farms Due to Mesoscale Atmospheric Response
by Kelan Patel, Thomas D. Dunstan and Takafumi Nishino
Energies 2021, 14(19), 6437; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196437 - 08 Oct 2021
Cited by 7 | Viewed by 2304
Abstract
A prototype of a new physics-based wind resource assessment method is presented, which allows the prediction of upper limits to the performance of large wind farms (including the power loss due to wind farm blockage) in a site-specific and time-dependent manner. The new [...] Read more.
A prototype of a new physics-based wind resource assessment method is presented, which allows the prediction of upper limits to the performance of large wind farms (including the power loss due to wind farm blockage) in a site-specific and time-dependent manner. The new method combines the two-scale momentum theory with a numerical weather prediction (NWP) model to assess the “extractability” of wind, i.e., how high the wind speed at a given site can be maintained as we increase the number of turbines installed. The new method is applied to an offshore wind farm site in the North Sea to demonstrate that: (1) Only a pair of NWP simulations (one without wind farm and the other with wind farm with an arbitrary level of flow resistance) are required to predict the extractability. (2) The extractability varies significantly from time to time, which may cause more than 30% of change in the upper limit of the performance of medium-to-high-density offshore wind farms. These results suggest the importance of considering not only the natural wind speed but also its extractability in the prediction of (both long- and short-term) power production of large wind farms. Full article
(This article belongs to the Special Issue Recent Advances in Wind Power Meteorology)
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25 pages, 7811 KiB  
Article
Sensitivity Analysis for Carbon Emissions of Prefabricated Residential Buildings with Window Design Elements
by Simeng Li, Yanqiu Cui, Nerija Banaitienė, Chunlu Liu and Mark B. Luther
Energies 2021, 14(19), 6436; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196436 - 08 Oct 2021
Cited by 4 | Viewed by 2650
Abstract
Owing to the advantages of high construction efficiency, prefabricated residential buildings have been of increasing interest in recent years. Against the background of global heating, designing low-carbon facades for prefabricated residential buildings has become a focus. The main challenge for this research is [...] Read more.
Owing to the advantages of high construction efficiency, prefabricated residential buildings have been of increasing interest in recent years. Against the background of global heating, designing low-carbon facades for prefabricated residential buildings has become a focus. The main challenge for this research is in designing windows for prefabricated residential buildings that can lead to the best performance in carbon emissions. The purpose of this paper is to summarize window design advice for prefabricated residential building facades with low-carbon goals. This paper adopts the single control variable research method. Building energy consumption and carbon dioxide emissions under different conditions comprise the primary data used in the study. In the process of achieving the research aim, this study firstly extracts the window design elements of prefabricated residential facades. Secondly, objective function formulas are established and a basic model is built for obtaining data. Thirdly, data results are analyzed and window design advice is put forward under the condition of a low-carbon goal. This paper discusses that the optimal window-to-wall ratio (WWR) with a low-carbon orientation is around 0.15, and compares it innovatively with the optimal WWR under an energy-saving orientation at around 0.38. The research results of this paper can deepen the understanding of architectural low-carbon design and play a guiding role for architects. Full article
(This article belongs to the Special Issue Innovations in Sustainable Architecture, Engineering and Construction)
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15 pages, 2233 KiB  
Article
An Extensive Study on Desorption Models Generated Based on Langmuir and Knudsen Diffusion
by Hamda Alkuwaiti, Hadi Belhaj, Mohammed Aldhuhoori, Bisweswar Ghosh and Ryan Fernandes
Energies 2021, 14(19), 6435; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196435 - 08 Oct 2021
Cited by 6 | Viewed by 1113
Abstract
Although gas desorption is a known phenomenon, modeling fluid flow in tight gas reservoirs often ignores the governing desorption effect, assuming that viscous transport is the predominant controller, resulting in an erroneous prediction of mass transport and fluid flow calculations. Thus, developing a [...] Read more.
Although gas desorption is a known phenomenon, modeling fluid flow in tight gas reservoirs often ignores the governing desorption effect, assuming that viscous transport is the predominant controller, resulting in an erroneous prediction of mass transport and fluid flow calculations. Thus, developing a new model accommodating all the major contributing forces in such a medium is essential. This work introduces a new comprehensive flow model suitable for tight unconventional reservoirs, including viscous, inertia, diffusion, and sorption forces, to account for fluid transport. Based on Langmuir law and Knudsen diffusion effect, three models were generated and compared with different known models using synthetic data. The model was solved and analyzed for different scenario cases, and parametric studies were conducted to evaluate the desorption effect on different reservoir types using MATLAB. Results show that the contribution of the sorption mechanism to the flow increases with the reducing permeability of the medium and lower viscosity of the flowing fluid and an additional pressure drop up to 10 psi was quantified. Full article
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13 pages, 2652 KiB  
Article
A Comprehensive Weight-Based Severity Evaluation Method of Voltage Sag in Distribution Networks
by Xiaohan Guo, Yong Li, Shaoyang Wang, Yijia Cao, Mingmin Zhang, Yicheng Zhou and Nakanishi Yosuke
Energies 2021, 14(19), 6434; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196434 - 08 Oct 2021
Cited by 7 | Viewed by 1630
Abstract
With the increasing use of sensitive loads in frequency converters and in relays in distribution networks, voltage sag has become a major power quality issue that urgently needs to be solved. For the purpose of improving the understanding of voltage sag severity in [...] Read more.
With the increasing use of sensitive loads in frequency converters and in relays in distribution networks, voltage sag has become a major power quality issue that urgently needs to be solved. For the purpose of improving the understanding of voltage sag severity in distribution networks, a comprehensive weight-based severity evaluation method of voltage sag is presented in this paper. First, a multi-side index system that takes into account the combined influence of the source, network, and the load is established. A comprehensive weight method, which combines the improved analytic hierarchy process (IAHP) and the entropy method, is then adopted to determine the index weight. The weight of each index and the degree of superiority are linearly weighted to obtain the severity of voltage sag at different observation points. Finally, the effectiveness of the proposed method is verified using a distribution network model established in DIgSILENT PowerFactory (15.1.7, Gomaringen, Germany). Full article
(This article belongs to the Special Issue Advances in Dynamic Voltage Restorers)
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21 pages, 7137 KiB  
Article
An Embedded Half-Bridge Γ-Z-Source Inverter with Reduced Voltage Stress on Capacitors
by Hamed Mashinchi Maheri, Dmitri Vinnikov, Mohsen Hasan Babayi Nozadian, Elias Shokati Asl, Ebrahim Babaei and Andrii Chub
Energies 2021, 14(19), 6433; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196433 - 08 Oct 2021
Cited by 5 | Viewed by 1583
Abstract
In this paper, an embedded half-bridge Z-source inverter based on gamma structure is proposed. In contrast with the classical half-bridge inverter, the proposed inverter can generate zero voltage levels in output. High voltage gain and low voltage stress on capacitors are the main [...] Read more.
In this paper, an embedded half-bridge Z-source inverter based on gamma structure is proposed. In contrast with the classical half-bridge inverter, the proposed inverter can generate zero voltage levels in output. High voltage gain and low voltage stress on capacitors are the main advantages of the proposed converter. The value of the boost factor in the proposed structure is increased by changing both the shoot-through (ST) duty cycle and turns ratio of the transformer. The operating principle of the proposed converter in four operating modes is presented. We also calculate the critical inductance and compare the proposed converter with conventional topologies. In addition, power loss and THD analysis are presented. Finally, PSCAD/EMTDC software is used to verify the correct operation of the proposed inverter and the experimental results. Full article
(This article belongs to the Special Issue Impedance Source Converters: Topologies, Control, and Applications)
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11 pages, 3698 KiB  
Article
Inertia Effects in the Dynamics of Viscous Fingering of Miscible Fluids in Porous Media: Circular Hele-Shaw Cell Configuration
by Hamid Ait Abderrahmane, Shahid Rabbani and Mohamed Sassi
Energies 2021, 14(19), 6432; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196432 - 08 Oct 2021
Viewed by 1631
Abstract
We present a numerical study of viscous fingering occurring during the displacement of a high viscosity fluid by low viscosity fluid in a circular Hele-Shaw cell. This study assumes that the fluids are miscible and considers the effects of inertial forces on fingering [...] Read more.
We present a numerical study of viscous fingering occurring during the displacement of a high viscosity fluid by low viscosity fluid in a circular Hele-Shaw cell. This study assumes that the fluids are miscible and considers the effects of inertial forces on fingering morphology, mixing, and displacement efficiency. This study shows that inertia has stabilizing effects on the fingering instability and improves the displacement efficiency at a high log-mobility-viscosity ratio between displacing and displaced fluids. Under certain conditions, inertia slightly reduces the finger-split phenomenon and the mixing between the two fluids. Full article
(This article belongs to the Special Issue Pore-Scale Multiphase Fluid Flow and Transport in Porous Media)
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16 pages, 4704 KiB  
Article
Calculation Method of Allowable Continuous Current for Direct Burial Laying HVDC Underground Cable
by Kyu-hoon Park, Il Kwon and Bang-wook Lee
Energies 2021, 14(19), 6431; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196431 - 08 Oct 2021
Cited by 4 | Viewed by 5042
Abstract
The calculation of the continuous allowable current of an underground cable is determined by various characteristics. To calculate the allowable current in cables with alternating magnetic fields such as AC, special phenomena such as the proximity effect and skin effect must be applied. [...] Read more.
The calculation of the continuous allowable current of an underground cable is determined by various characteristics. To calculate the allowable current in cables with alternating magnetic fields such as AC, special phenomena such as the proximity effect and skin effect must be applied. However, there are no standards or research related to the calculation of the continuous allowable current of a DC power cable that does not have an alternating magnetic field. In this paper, a quantitative DC cable continuous allowable current calculation formula of direct burial laying was derived by applying the existing AC cable continuous allowable current calculation method to the DC system. We developed a calculation tool that can calculate the continuous allowable current of DC cables using the derived formula. Assuming the cable conditions (cable specification, laying conditions, soil characteristics, arrangement, and number of strands, etc.), a continuous allowable current simulation of DC cables was performed. In addition, the level of contribution to the continuous allowable current value was analyzed by classifying the parameter categories into major and minor factors in the order of influence on the allowable current among the determined calculated parameters. As a result, the effectiveness of the DC cable continuous allowable current calculation tool derived by performing the allowable current calculation simulation was evaluated, and the allowable current calculation method of the HVDC cable was established. Full article
(This article belongs to the Special Issue HVDC Grid Technologies: Present and Future)
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28 pages, 3047 KiB  
Article
Can Lower Carbon Aviation Fuels (LCAF) Really Complement Sustainable Aviation Fuel (SAF) towards EU Aviation Decarbonization?
by David Chiaramonti, Giacomo Talluri, George Vourliotakis, Lorenzo Testa, Matteo Prussi and Nicolae Scarlat
Energies 2021, 14(19), 6430; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196430 - 08 Oct 2021
Cited by 8 | Viewed by 5953
Abstract
The present work provides an analysis of the potential impact of fossil-based Low Carbon Aviation Fuels (LCAF) for the European aviation sector, with a time horizon to 2050. LCAF are a crude-derived alternative to kerosene, offering some Green House Gas (GHG) savings, and [...] Read more.
The present work provides an analysis of the potential impact of fossil-based Low Carbon Aviation Fuels (LCAF) for the European aviation sector, with a time horizon to 2050. LCAF are a crude-derived alternative to kerosene, offering some Green House Gas (GHG) savings, and have been defined by ICAO as eligible fuels for mitigating the environmental impact of aviation. A methodological framework to evaluate the EU technical potential for LCAF production is developed, based on data on crude utilization for jet fuel production in EU refineries, relevant carbon intensity reduction technologies, market prices, and aviation fuel volumes. Two different baselines for fossil-derived kerosene carbon intensity (CI) are considered: a global figure of 89 gCO2e/MJ and an EU-27-specific one of 93.1 gCO2eq/MJ. Three scenarios considering increasing levels of CI reduction are then defined, taking into account the current and potential commercial availability of some of the most relevant carbon intensity reduction technologies. The analysis demonstrates that, even if LCAF could offer GHG saving opportunities, their possible impact, especially when compared to the ambition level set in the most recent European legislative proposals, is very limited in most of the analysed scenarios, with the exception of the most ambitious ones. At 2030, a non-zero technical potential is projected only in the higher CI reduction scenario, ranging between 1.8% and 14.2% of LCAF market share in the EU-27 (equal to 0.6 to 4.75 Mtoe), depending on the considered Baseline for CI. At 2050, almost all considered scenarios project a larger technical potential, ranging between 6.9% and 22.2% for the global Baseline (2.21 to 7.13 Mtoe), and between 1.8% and 16.2% for the EU-27 Baseline (0.58 to 5.2 Mtoe). LCAF additional costs to current production costs are also discussed, given their relevance in large-scale deployment of these technologies, and are projected to range between 39 and 46.8 USD/toe. Full article
(This article belongs to the Section I1: Fuel)
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20 pages, 69949 KiB  
Article
A New Tool for Building Energy Optimization: First Round of Successful Dynamic Model Simulations
by Giacomo Chiesa, Francesca Fasano and Paolo Grasso
Energies 2021, 14(19), 6429; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196429 - 08 Oct 2021
Cited by 7 | Viewed by 2798
Abstract
Several tools and pieces of software support building energy modelling for optimization, certification and comparisons of different scenarios and usages. Nevertheless, the consistent rise in accessible computational power and the expansion of ICT are pushing the development of new software functionalities and tools [...] Read more.
Several tools and pieces of software support building energy modelling for optimization, certification and comparisons of different scenarios and usages. Nevertheless, the consistent rise in accessible computational power and the expansion of ICT are pushing the development of new software functionalities and tools able to support cross-disciplinary work on smart building optimization. This paper introduces a new platform (under development) that combines the EnergyPlus dynamic simulation tool with extra-functionalities and pre-defined usage scenarios based on automatic actions to manage massive simulations and correlation analyses. The tool’s utility was tested in three experiments, with goals that we consider to be fundamental requirements: comparing simple retrofit actions to reduce net energy needs; analyzing the free-running potential of a demo building and the impacts of different low-energy technologies in terms of increasing thermal comfort (shading and ventilative cooling); and comparing measured sensor data indicators with simulated ones under real weather conditions for model verification. The results demonstrate the ability of the tool to automatically generate hundreds of EnergyPlus input building models by acting on building geometry; we focused on the most common uses for parametric dynamic simulations. Additionally, the way in which the tool combines the automatic modification of the building’s design and the parallel launching of multiple simulations allows the labor to be reduced. The user can execute complex tasks without spending any time working with model editing software and aggregating the results from multiple simulations. Full article
(This article belongs to the Section G: Energy and Buildings)
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19 pages, 79062 KiB  
Article
Duct Attachment on Improving Breaking Wave Zone Energy Extractor Device Performance
by Krisna Adi Pawitan, Hideki Takebe, Hanley Andrean, Shuji Misumi, Jun Fujita and Tsumoru Shintake
Energies 2021, 14(19), 6428; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196428 - 08 Oct 2021
Cited by 1 | Viewed by 1450
Abstract
A challenging wave energy converter design that utilized the denser energy part of the nearshore breaking wave zone to generate electricity was introduced in 2016 by Shintake. The Okinawa Institute of Science and Technology Graduate University’s project aims to take advantage of breaking [...] Read more.
A challenging wave energy converter design that utilized the denser energy part of the nearshore breaking wave zone to generate electricity was introduced in 2016 by Shintake. The Okinawa Institute of Science and Technology Graduate University’s project aims to take advantage of breaking wave energy to harness electricity. The 2016 version of the device consisted only of a bare turbine and power generator. Early exploration of the design recorded short periods and high impact wave pressures were experienced by the structure, with the turbine unable to harvest energy effectively. Additional structure to not only reduce incoming impact pressure but also increase the duration of water flow through the turbine was needed. These are the main reasons behind incorporating the duct attachment into the design. This paper show that the duct is capable of halving the impact pressure experienced by the turbine and can increase the energy exposure by up to 1.6 times the bare turbine configuration. Furthermore, it is also said that wave angle (β) = 40° is the critical angle, although the duct still increases wave energy exposure to the power take-off up to β = 60°. Full article
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37 pages, 17011 KiB  
Article
Solar Irradiation Evaluation through GIS Analysis Based on Grid Resolution and a Mathematical Model: A Case Study in Northeast Mexico
by Fausto André Valenzuela-Domínguez, Luis Alfonso Santa Cruz, Enrique A. Enríquez-Velásquez, Luis C. Félix-Herrán, Victor H. Benitez, Jorge de-J. Lozoya-Santos and Ricardo A. Ramírez-Mendoza
Energies 2021, 14(19), 6427; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196427 - 08 Oct 2021
Cited by 3 | Viewed by 2051
Abstract
The estimation of the solar resource on certain surfaces of the planet is a key factor in deciding where to establish solar energy collection systems. This research uses a mathematical model based on easy-access geographic and meteorological information to calculate total solar radiation [...] Read more.
The estimation of the solar resource on certain surfaces of the planet is a key factor in deciding where to establish solar energy collection systems. This research uses a mathematical model based on easy-access geographic and meteorological information to calculate total solar radiation at ground surface. This information is used to create a GIS analysis of the State of Nuevo León in Mexico and identify solar energy opportunities in the territory. The analyzed area was divided into a grid and the coordinates of each corner are used to feed the mathematical model. The obtained results were validated with statistical analyses and satellite-based estimations from the National Aeronautics and Space Administration (NASA). The applied approach and the results may be replicated to estimate solar radiation in other regions of the planet without requiring readings from on-site meteorological stations and therefore reducing the cost of decision-making regarding where to place the solar energy collection equipment. Full article
(This article belongs to the Special Issue GIS and Remote Sensing for Renewable Energy Assessment and Maps)
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29 pages, 11731 KiB  
Article
Numerical Analysis and Parameter Optimization of J-Shaped Blade on Offshore Vertical Axis Wind Turbine
by Lin Pan, Ze Zhu, Haodong Xiao and Leichong Wang
Energies 2021, 14(19), 6426; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196426 - 08 Oct 2021
Cited by 7 | Viewed by 1811
Abstract
In this study, the performance of offshore wind turbines at low tip speed ratio (TSR) is studied using computational fluid dynamics (CFD), and the performance of offshore wind turbines at low tip speed ratio (TSR) is improved by revising the blade structure. First, [...] Read more.
In this study, the performance of offshore wind turbines at low tip speed ratio (TSR) is studied using computational fluid dynamics (CFD), and the performance of offshore wind turbines at low tip speed ratio (TSR) is improved by revising the blade structure. First, the parameters of vertical axis offshore wind turbine are designed based on the compactness iteration, a CFD simulation model is established, and the turbulence model is selected through simulation analysis to verify the independence of grid and time step. Compared with previous experimental results, it is shown that the two-dimensional simulation only considers the plane turbulence effect, and the simulation turbulence effect performs more obviously at a high tip ratio, while the three-dimensional simulation turbulence effect has well-fitting performance at high tip ratio. Second, a J-shaped blade with optimized lower surface is proposed. The study showed that the optimized J-shaped blade significantly improved its upwind torque and wind energy capture rate. Finally, the performance of the optimized J-blade offshore wind turbine is analyzed. Full article
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22 pages, 3139 KiB  
Article
Analysis of Performance of Cavitation Models with Analytically Calculated Coefficients
by Andrea Savio, Marta Cianferra and Vincenzo Armenio
Energies 2021, 14(19), 6425; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196425 - 08 Oct 2021
Cited by 2 | Viewed by 1949
Abstract
Cavitation is often simulated using a mixture model, which considers the transport of an active scalar, namely the vapor fraction αv. Source and sink terms of the transport equation of αv, namely vaporization and condensation terms, rule the dynamics [...] Read more.
Cavitation is often simulated using a mixture model, which considers the transport of an active scalar, namely the vapor fraction αv. Source and sink terms of the transport equation of αv, namely vaporization and condensation terms, rule the dynamics of the cavity and are described through different models. These models contain empirical coefficients generally calibrated through optimization processes. The purpose of this paper is to propose an analytical approach for the calculation of the coefficients, based on the time scales of vaporization and condensation processes. Four different models are compared considering as a test-case a two-dimensional flow around a cylinder. Some relevant quantities are analyzed both for standard value of coefficients, as found in the literature, and the coefficients calculated through the analytical approach. The study shows that the analytical computation of the coefficients of the model substantially improve the results, and the models considered give similar results, both in terms of cavitation regime and mean vapor fraction produced. Full article
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25 pages, 25709 KiB  
Article
Operation Strategy of Electricity Retailers Based on Energy Storage System to Improve Comprehensive Profitability in China’s Electricity Spot Market
by Ting Lu, Weige Zhang and Xiaowei Ding
Energies 2021, 14(19), 6424; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196424 - 08 Oct 2021
Cited by 5 | Viewed by 1634
Abstract
Due to the development of China’s electricity spot market, the peak-shifting operation modes of energy storage devices (ESD) are not able to adapt to real-time fluctuating electricity prices. The settlement mode of the spot market aggravates the negative impact of deviation assessments on [...] Read more.
Due to the development of China’s electricity spot market, the peak-shifting operation modes of energy storage devices (ESD) are not able to adapt to real-time fluctuating electricity prices. The settlement mode of the spot market aggravates the negative impact of deviation assessments on the cost of electricity retailers. This article introduces the settlement rules of China’s power spot market. According to the electricity cost settlement process and the assessment methods, this paper proposes a comprehensive electricity cost optimization algorithm that optimizes day-ahead market (DA) electricity cost, real-time market (RT) electricity cost and deviation assessment through ESD control. According to the trial electricity price data of the power trading center in Guangdong province (China), many typical load curves and different deviation assessment policies, the algorithm calculates DA electricity cost, RT electricity cost and deviation assessment cost by utilizing a comprehensive electricity cost optimization algorithm. Compared with the original electricity cost and optimization cost, this method is proven to effectively save overall electricity costs under the spot market settlement system. Based on three different initial investment prices of ESD, this paper analyzes the economics of the ESD system and proves that ESD investment can be recovered within 5 years. Considering the small amounts of operating data in China’s power spot market, the algorithm generates random data according to characteristics of these data. Then, this paper verifies that the comprehensive electricity cost optimization algorithm remains reliable under random circumstances. Full article
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19 pages, 1609 KiB  
Article
Flexibility from Combined Heat and Power: A Techno-Economic Study for Fully Renewable Åland Islands
by Tomi Thomasson, Kirsikka Kiviranta, Antton Tapani and Matti Tähtinen
Energies 2021, 14(19), 6423; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196423 - 08 Oct 2021
Cited by 4 | Viewed by 1352
Abstract
As energy systems globally are transitioning into renewable energy, simultaneous targets of high self-sufficiency have led to complex system design proposals. While conventional technology solutions would reduce the complexity in theory, limitations in the potential outcome may exist. To address this dilemma, the [...] Read more.
As energy systems globally are transitioning into renewable energy, simultaneous targets of high self-sufficiency have led to complex system design proposals. While conventional technology solutions would reduce the complexity in theory, limitations in the potential outcome may exist. To address this dilemma, the work quantified the systemic value provided by a conventional solution; biomass combined heat and power (CHP) production, in terms of economic feasibility, provided flexibility and energy self-sufficiency. The analysis focused on the renewable energy integration of the Åland Islands, where the synergetic island energy system is heavily increasing the wind power capacity. While considering local fuel resource availability, multiple alternative energy system scenarios were constructed. To evaluate the scenarios, the work developed and validated a combined dispatch and investment optimization model. The results showed that the studied conventional approaches limited the achievable self-sufficiency in the power sector (80.6%), however, considerably increasing the value from the present state (18.5%). Second, compared to previous studies, the results indicated a low value from biomass CHP in the wind-based energy system. Instead, the combination of high wind capacity and power-to-heat enabled the best economic feasibility and high self-sufficiency, which could be further improved by lower electricity taxation. Full article
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22 pages, 1083 KiB  
Article
Bank as a Stakeholder in the Financing of Renewable Energy Sources. Recommendations and Policy Implications for Poland
by Karolina Daszyńska-Żygadło, Krzysztof Jajuga and Justyna Zabawa
Energies 2021, 14(19), 6422; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196422 - 08 Oct 2021
Cited by 2 | Viewed by 2132
Abstract
The paper concerns the role of the banking sector in renewable energy financing in Poland. The main goal of the paper is to provide recommendations for the banking sector in Poland, which can be used in the process of financing RES. The main [...] Read more.
The paper concerns the role of the banking sector in renewable energy financing in Poland. The main goal of the paper is to provide recommendations for the banking sector in Poland, which can be used in the process of financing RES. The main methods used in the paper are the thorough analysis of the solutions used to finance RES in different countries and multivariate analysis of options presented on the ordinal scale. The first finding is the answer to the question of which financial instruments used by banks are the most effective in the financing of RES. It is based on the prepared ranking of different instruments used by banks in the process of renewable energy financing, by assessing the structure and value of required financing for renewable energy based on future scenarios. The second finding in the paper is the set of recommendations for the banking sector and policymakers as to financing renewable energy sources in Poland. The main conclusion is that renewable energy financing through the instruments available in the banking sector is efficient and is characterized by relatively low risk. Full article
(This article belongs to the Special Issue Investment Analysis of Renewable Energy)
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16 pages, 3268 KiB  
Article
Study on the Relationship between Combustion Parameters and Cylinder Head Vibration Signal in Time Domain
by Shaobo Ji, Yang Li, Guohong Tian, Rongze Ma, Minglei Shu, Shiqiang Zhang, Wenbin Yu, Xin Lan and Yong Cheng
Energies 2021, 14(19), 6421; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196421 - 08 Oct 2021
Cited by 3 | Viewed by 1686
Abstract
Combustion-related characteristic parameters, such as the start of combustion (SoC) and the timing of the peak pressure increase rate (PIR), can be used as the feedback signals for the closed-loop control of combustion. A dynamic Finite Element Method (FEM) model was firstly developed [...] Read more.
Combustion-related characteristic parameters, such as the start of combustion (SoC) and the timing of the peak pressure increase rate (PIR), can be used as the feedback signals for the closed-loop control of combustion. A dynamic Finite Element Method (FEM) model was firstly developed to confirm the closely related time period between combustion pressure and vibration. On this basis, a fast processing method was developed to estimate the timings of SoC and the peak PIR in the closely related time period. This method was verified on a twelve-cylinder heavy-duty diesel engine at various engine speed and load. Results showed that the maximum deviation of the two parameters were within 2 °CA and 1.5 °CA, respectively, which suggested that the proposed method had an adequate accuracy. Full article
(This article belongs to the Collection Advanced Technology of Internal Combustion Engines in China)
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29 pages, 4504 KiB  
Article
Global Sensitivity Analysis Applied to Train Traffic Rescheduling: A Comparative Study
by Soha Saad, Florence Ossart, Jean Bigeon, Etienne Sourdille and Harold Gance
Energies 2021, 14(19), 6420; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196420 - 08 Oct 2021
Cited by 1 | Viewed by 1501
Abstract
The adjustment of rail traffic in the event of an electrical infrastructure disruption presents an important decision-making process for the smooth operation of the network. Railway systems are complex, and their analysis relies on expensive simulations, which makes incident management difficult. This paper [...] Read more.
The adjustment of rail traffic in the event of an electrical infrastructure disruption presents an important decision-making process for the smooth operation of the network. Railway systems are complex, and their analysis relies on expensive simulations, which makes incident management difficult. This paper proposes the use of sensitivity analysis in order to evaluate the influence of different traffic adjustment actions (e.g., spacing between trains and speed reduction) on the train supply voltage, which must never drop below the critical value prescribed by technical standards. Three global sensitivity analysis methods dedicated to black box, multivariate, nonlinear models are considered: generalized Sobol indices, energy distance-based indices, and regional sensitivity analysis. The three methods are applied to a simple traffic rescheduling test case and give similar results, but at different costs. Regional sensitivity analysis appears to be the most suitable method for the present application: it is easy to implement, rather fast, and accounts for constraints on the system output (a key feature for electrical incident management). The application of this method to a test case representative of a real rescheduling problem shows that it provides the information needed by the traffic manager to reschedule traffic in an efficient way. The same type of approach can be used for any power system optimization problem with the same characteristics. Full article
(This article belongs to the Special Issue Simulation and Optimization of Electrotechnical Systems)
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24 pages, 8107 KiB  
Article
Development and Analysis of a Dynamic Energy Model of an Office Using a Building Management System (BMS) and Actual Measurement Data
by Rasa Džiugaitė-Tumėnienė, Rūta Mikučionienė, Giedrė Streckienė and Juozas Bielskus
Energies 2021, 14(19), 6419; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196419 - 08 Oct 2021
Cited by 4 | Viewed by 2202
Abstract
Calibration of the energy model of a building is one of the essential tasks required to determine the efficiency of building management systems, and both their own and other systems’ improvement potential. In order to make the building energy model as accurate as [...] Read more.
Calibration of the energy model of a building is one of the essential tasks required to determine the efficiency of building management systems, and both their own and other systems’ improvement potential. In order to make the building energy model as accurate as possible, it is necessary to collect comprehensive data on its operation and sometimes to assess the missing information. This paper represents the process of developing an energy model for an administrative building and its calibration procedure, using detailed long-term measurement and building management system (BMS) data. Indoor air temperature, CO₂ concentration, and relative humidity were experimentally measured and evaluated separately. Such dual application of data reduces the inaccuracy of the assumptions made and assesses the model’s accuracy. The DesignBuilder software developed the building model. During the development of the model, it was observed that the actual energy consumption needs to be assessed, as the assumptions made during the design about the operation and management of HVAC systems often do not coincide with the actual situation. After integrating BMS information on HVAC management into the building model, the resulting discrepancy between the model results and the actual heat consumption was 6.5%. Such a model can be further used to optimize management decisions and assess energy savings potential. Full article
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14 pages, 2218 KiB  
Article
Solar Photovoltaic Investment Changes across China Regions Using a Spatial Shift-Share Analysis
by Ruxu Sheng, Juntian Du, Songqi Liu, Changan Wang, Zidi Wang and Xiaoqian Liu
Energies 2021, 14(19), 6418; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196418 - 08 Oct 2021
Cited by 4 | Viewed by 1485
Abstract
Solar photovoltaic (PV) has become the fastest-growing new energy in China and one of the main contributors to China’s clean energy transition. From 2013 to 2019, China’s solar PV installed capacity grew from 15,890 MW to 204,180 MW, increasing by 11.85 times. To [...] Read more.
Solar photovoltaic (PV) has become the fastest-growing new energy in China and one of the main contributors to China’s clean energy transition. From 2013 to 2019, China’s solar PV installed capacity grew from 15,890 MW to 204,180 MW, increasing by 11.85 times. To explore solar PV investment changes across China regions, we use spatial shift-share analysis model to decompose solar PV investment changes from 2013 to 2019 into four components: national energy investment growth effect (NEG), national energy investment structure effect (NES), neighbor–nation solar PV investment competitive effect (NNC), and region–neighbor solar PV investment competitive effect (RNC). Based on the decomposition results, we find that the value of NNC of most western provinces is negative for the entire period, while the NNC of most central and eastern provinces is in the middle and lower range. There is little difference in RNC among these regions. While comparing the influence caused by the four effects, NNC and RNC play dominant roles in solar PV investment changes in eastern and central provinces, which means NEG and NES have relatively small impacts. By contrast, NEG and NES affect the solar PV investment changes at a larger scale in most western provinces. Comparing the NNC and RNC, we find that RNC played a prominent role in the eastern and central regions, while NNC played a dominant role in the west. Full article
(This article belongs to the Special Issue Low Carbon Energy Transitions: Today and in the Future)
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26 pages, 8865 KiB  
Article
OC6 Phase Ib: Floating Wind Component Experiment for Difference-Frequency Hydrodynamic Load Validation
by Amy Robertson and Lu Wang
Energies 2021, 14(19), 6417; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196417 - 08 Oct 2021
Cited by 6 | Viewed by 2549
Abstract
A new validation campaign was conducted at the W2 Harold Alfond Ocean Engineering Laboratory at the University of Maine to investigate the hydrodynamic loading on floating offshore wind substructures, with a focus on the low-frequency contributions that tend to drive extreme and fatigue [...] Read more.
A new validation campaign was conducted at the W2 Harold Alfond Ocean Engineering Laboratory at the University of Maine to investigate the hydrodynamic loading on floating offshore wind substructures, with a focus on the low-frequency contributions that tend to drive extreme and fatigue loading in semisubmersible designs. A component-level approach was taken to examine the hydrodynamic loads on individual parts of the semisubmersible in isolation and then in the presence of other members to assess the change in hydrodynamic loading. A variety of wave conditions were investigated, including bichromatic waves, to provide a direct assessment of difference-frequency wave loading. An assessment of the impact of wave uncertainty on the loading was performed, with the goal of enabling validation with this dataset of numerical models with different levels of fidelity. The dataset is openly available for public use and can be downloaded from the U.S. Department of Energy Data Archive and Portal. Full article
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23 pages, 1382 KiB  
Article
Design of a Neural Super-Twisting Controller to Emulate a Flywheel Energy Storage System
by Daniel A. Magallón, Carlos E. Castañeda, Francisco Jurado and Onofre A. Morfin
Energies 2021, 14(19), 6416; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196416 - 07 Oct 2021
Cited by 4 | Viewed by 2129
Abstract
In this work, a neural super-twisting algorithm is applied to the design of a controller for a flywheel energy storage system (FESS) emulator. Emulation of the FESS is achieved through driving a Permanent Magnet Synchronous Machine (PMSM) coupled to a shaft to shaft [...] Read more.
In this work, a neural super-twisting algorithm is applied to the design of a controller for a flywheel energy storage system (FESS) emulator. Emulation of the FESS is achieved through driving a Permanent Magnet Synchronous Machine (PMSM) coupled to a shaft to shaft DC-motor. The emulation of the FESS is carried out by controlling the velocity of the PMSM in the energy storage stag and then by controlling the DC-motor velocity in the energy feedback stage, where the plant’s states of both electrical machines are identified via a neural network. For the neural identification, a Recurrent Wavelet First-Order Neural Network (RWFONN) is proposed. For the design of the velocity controller, a super-twisting algorithm is applied by using a sliding surface as the argument; the latter is designed based on the states of the RWFONN, in combination with the block control linearization technique to the control of the angular velocity from both machines in their respective operation stage. The RWFONN is trained online using the filtered error algorithm. Closed-loop stability analysis is included when assuming boundedness of the synaptic weights. The results obtained from Matlab/Simulink validate the performance of the proposal in the control of an FESS. Full article
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22 pages, 2946 KiB  
Article
Improving the Electrical Efficiency of the PV Panel via Geothermal Heat Exchanger: Mathematical Model, Validation and Parametric Analysis
by Evangelos I. Sakellariou, Petros J. Axaopoulos, Ioannis E. Sarris and Nodirbek Abdullaev
Energies 2021, 14(19), 6415; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196415 - 07 Oct 2021
Cited by 1 | Viewed by 1436
Abstract
Silicon based photovoltaic modules (PV) are a wide spread technology and are used for small and large PV power stations. At the moment, the most efficient method which can be used to improve the annual electrical energy production of PVs is solar tracking [...] Read more.
Silicon based photovoltaic modules (PV) are a wide spread technology and are used for small and large PV power stations. At the moment, the most efficient method which can be used to improve the annual electrical energy production of PVs is solar tracking systems. However, solar tracking systems increase substantially the initial cost of the investment and insert maintenance costs. During the last few decades, alternative improving methods have been investigated. These methods are based on the reduction of the PV cell temperature, which adversely affects the power production. In the present study, a system with water based photovoltaic-thermal (PVT) collector paired with geothermal heat exchanger (GHE) is compared on the electrical energy basis with a conventional PV system. As the first approach on the topic, the aim is to find out in which extent the PVT-GHE system improves the electrical energy generation by cooling down the PV cells and which parameters influence the most its energy performance. With this aim in mind, the model of the system with the PV, PVT, and GHE was formulated in TRNSYS and validated via experimental data. Meteorological data for Athens (Greece) were used and parametric analyses were conducted. The results showed that the PVT based system can increase the generated electricity from 0.61 to 5.5%. The flowrate, the size of the GHE and the number in-series connected PVTs are the parameters which influence the most the energy performance of the system. Full article
(This article belongs to the Special Issue Novel Design of Solar Assisted Ground Source Heat Pump Systems)
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15 pages, 3654 KiB  
Article
Energy-Efficient IoT e-Health Using Artificial Intelligence Model with Homomorphic Secret Sharing
by Amjad Rehman, Tanzila Saba, Khalid Haseeb, Souad Larabi Marie-Sainte and Jaime Lloret
Energies 2021, 14(19), 6414; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196414 - 07 Oct 2021
Cited by 16 | Viewed by 2088
Abstract
Internet of Things (IoT) is a developing technology for supporting heterogeneous physical objects into smart things and improving the individuals living using wireless communication systems. Recently, many smart healthcare systems are based on the Internet of Medical Things (IoMT) to collect and analyze [...] Read more.
Internet of Things (IoT) is a developing technology for supporting heterogeneous physical objects into smart things and improving the individuals living using wireless communication systems. Recently, many smart healthcare systems are based on the Internet of Medical Things (IoMT) to collect and analyze the data for infectious diseases, i.e., body fever, flu, COVID-19, shortness of breath, etc. with the least operation cost. However, the most important research challenges in such applications are storing the medical data on a secured cloud and make the disease diagnosis system more energy efficient. Additionally, the rapid explosion of IoMT technology has involved many cyber-criminals and continuous attempts to compromise medical devices with information loss and generating bogus certificates. Thus, the increase in modern technologies for healthcare applications based on IoMT, securing health data, and offering trusted communication against intruders is gaining much research attention. Therefore, this study aims to propose an energy-efficient IoT e-health model using artificial intelligence with homomorphic secret sharing, which aims to increase the maintainability of disease diagnosis systems and support trustworthy communication with the integration of the medical cloud. The proposed model is analyzed and proved its significance against relevant systems. Full article
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16 pages, 39437 KiB  
Article
An Anti-Fluctuation Compensator Design and Its Control Strategy for Wind Farm System
by Feng-Chang Gu and Hung-Cheng Chen
Energies 2021, 14(19), 6413; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196413 - 07 Oct 2021
Cited by 1 | Viewed by 1594
Abstract
Large-scale wind farms in commercial operations have demonstrated growing influence on the stability of an electricity network and the power quality thereof. Variations in the output power of large-scale wind farms cause voltage fluctuations in the corresponding electrical networks. To achieve low-voltage ride-through [...] Read more.
Large-scale wind farms in commercial operations have demonstrated growing influence on the stability of an electricity network and the power quality thereof. Variations in the output power of large-scale wind farms cause voltage fluctuations in the corresponding electrical networks. To achieve low-voltage ride-through capability in a doubly fed induction generator (DFIG) during a fault event, this study proposes a real-time reactive power control strategy for effective DFIG application and a static synchronous compensator (STATCOM) for reactive power compensation. Mathematic models were developed for the DFIG and STATCOM, followed by the development of an indirect control scheme for the STATCOM based on decoupling dual-loop current control. Moreover, a real-world case study on a commercial wind farm comprising 23 DFIGs was conducted. The voltage regulation performance of the proposed reactive power control scheme against a fault event was also simulated. The simulation results revealed that enhanced fault ride-through capability and prompt recovery of the output voltage provided by a wind turbine generator could be achieved using the DFIG along with the STATCOM in the event of a three-phase short-circuit fault. Full article
(This article belongs to the Topic Power System Modeling and Control)
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19 pages, 6259 KiB  
Article
Impact of Weather Conditions on the Operation of Power Unit Cooling Towers 905 MWe
by Zbigniew Buryn, Anna Kuczuk, Janusz Pospolita, Rafał Smejda and Katarzyna Widera
Energies 2021, 14(19), 6412; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196412 - 07 Oct 2021
Cited by 3 | Viewed by 1912
Abstract
The paper presents the results of measurements and calculations concerning the influence of weather conditions on the operation of wet cooling towers of 905 MWe units of the Opole Power Plant (Poland). The research concerned the influence of temperature and relative humidity of [...] Read more.
The paper presents the results of measurements and calculations concerning the influence of weather conditions on the operation of wet cooling towers of 905 MWe units of the Opole Power Plant (Poland). The research concerned the influence of temperature and relative humidity of air, wind and power unit load on the water temperature at the outlet from the cooling tower, the level of water cooling, cooling efficiency and cooling water losses. In the cooling water loss, the evaporation loss stream and the drift loss stream were distinguished. In the analyzed operating conditions of the power unit, for example, an increase in Tamb air by 5 °C (from 2022 °C to 2527 °C) causes an increase in temperature at the outlet of the cooling tower by 34 °C. The influence of air temperature and humidity on the level of water cooling ΔTw and cooling efficiency ε were also found. In the case of ΔTw, the effect is in the order of 0.10.2 °C and results from the change in cooling water temperature and the heat exchange in the condenser. The ε value is influenced by air temperature and humidity, which determine the wet bulb temperature value. Within the range of power changes of the unit from 400 to 900 MWe, the evaporated water stream m˙ev, depending on the environmental conditions, increases from 400600 tons/h to the value of 10001400 tons/h. It was determined that in the case of the average power of the unit at the level of 576.6 MWe, the average values of the evaporation and drift streams were respectively 0.78% and 0.15% of the cooling water stream. Using statistical methods, it was found that the influence of wind on the level of water cooling, cooling efficiency and cooling water losses was statistically significant. Full article
(This article belongs to the Special Issue Energy Management and Economics Analyses)
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22 pages, 2238 KiB  
Article
The Legal Governance of Oil and Gas in Europe: An Indicator Analysis of the Implementation of the Hydrocarbons Directive
by Tamás Hámor, Katalin Bódis and Mária Hámor-Vidó
Energies 2021, 14(19), 6411; https://0-doi-org.brum.beds.ac.uk/10.3390/en14196411 - 07 Oct 2021
Cited by 4 | Viewed by 2374
Abstract
Hydrocarbons are traditional subjects to European Union (EU) law (“acquis communitaire”). A short historical review reveals that quasi all aspects of upstream and downstream segments are covered by the legislation. The results of applied information extraction and elaborated quantitative analysis indicate that the [...] Read more.
Hydrocarbons are traditional subjects to European Union (EU) law (“acquis communitaire”). A short historical review reveals that quasi all aspects of upstream and downstream segments are covered by the legislation. The results of applied information extraction and elaborated quantitative analysis indicate that the intensity of legislation making correlates with global drivers such as oil price booms, and technology developments such as extraction of unconventional hydrocarbons by hydraulic fracturing. A quarter of a century after the Hydrocarbons Directive was published and transposed by Member States (MS), data allow us to make a semi-quantitative assessment on the implementation, the major drivers of governments’ publication activity, and the impact on the oil and gas production. Another specific relevance of this study is on non-energy minerals management of the EU, whether the introduction of similar competitive bidding rules would induce a greater interest of investors, and the enhanced competition could bring more benefits to the states by the rejuvenation of the critical minerals extractive sector. The preliminary findings show that in some MS there is a positive correlation between the concession call publication activity and hydrocarbons production. To confirm these conclusions the analysis of an extended dataset including exploration data, investments, and social impacts is needed in order to screen the effect of global market trends, the exhaustion of domestic geological reserves, and the different policy environments. Full article
(This article belongs to the Section H: Geo-Energy)
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