Energy Engineering

ISSN: 0199-8595 (print)
ISSN: 1546-0118 (online) Publication Frequency: Bi-monthly

About the Journal

Energy Engineering is a bi-monthly peer-reviewed publication. The journal invites researchers, engineers, scientists, technologists, planners, and policy makers to present their original research results and findings on all important energy topics.

Indexing and Abstracting

Ei Compendex; WorldCat; Scopus...

Previously published by Taylor&Francis Group (https://www.tandfonline.com/toc/uene20/current), Energy Engineering starts to be published by Tech Science Press from 2020 and supports Open Access Policy.
From 1st May 2020, an Article Processing Charge (APC) of $600 US dollars applies to papers accepted after peer review.

Current Issue - Vol.117, No.6, 2020 Most Viewed

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ARTICLE
Wind Farm-Battery Energy Storage Assessment in Grid-Connected Microgrids
Shafiqur Rehman¹, Umar T. Salman^2,*, Luai M. Alhems¹
Energy Engineering, Vol.117, No.6, pp. 343-365, 2020, DOI:10.32604/EE.2020.011471
Abstract Renewable energy has received much attention in the last few decades and more investment is being attracted across the world to boost its contribution towards the existing energy mix. In the Kingdom of Saudi Arabia (KSA), many studies have been conducted on the potential of renewable energy sources (RES), such as wind, solar, and geothermal. Many of these studies have revealed that the Kingdom is blessed with an abundance of RES with wind energy being the best after solar. This paper presents an analysis of windfarm distributed generation (WFDG) for energy management strategy in the Eastern Province of KSA. The… More
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Improved Thermal Efficiency of Salinity Gradient Solar Pond by Suppressing Surface Evaporation Using an Air Layer
Asaad H. Sayer¹, Hameed B. Mahood^2,*
Energy Engineering, Vol.117, No.6, pp. 367-379, 2020, DOI:10.32604/EE.2020.011156
Abstract Salinity gradient solar ponds (SGSPs) provide a tremendous way to collect and store solar radiation as thermal energy, and can help meet the critical need for sustainable ways of producing fresh water. However, surface evaporation results in the loss of both water and heat. This study therefore theoretically investigates the effect on temperatures within an SGSP when its surface is covered with a layer of air encased in a nylon bag. An earlier SGSP model was slightly modified to add the air layer and to estimate the temperature distributions of the upper layer or the upper convective zone (UCZ) and… More
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ARTICLE
Energy Retrofitting of School Buildings in UAE
Abdelsalam Aldawoud^*, Fatma Elzahraa Hosny, Rasha Mdkhana
Energy Engineering, Vol.117, No.6, pp. 381-395, 2020, DOI:10.32604/EE.2020.011863
Abstract The opportunities for energy savings by retrofitting of the existing school buildings in the United Arab Emirates (UAE) are significant because of their excessive energy consumption and space cooling demand. In this research, energy modeling and simulation are utilized with the use of Design Builder software to examine the influence of various retrofitting measures of air-conditioning (A/C) system and building envelope components on the energy use. Several combined measures are implemented and assessed to achieve the main goal of this research of selecting the best course of action to reduce cooling energy consumption for existing school buildings in the UAE.… More
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Research on Distribution Network Full Cost-Benefit Optimization Considering Different Renewable Energy Penetration
Tanzhong Fu^1,2,3, Yu Xue^1,*, Tancai Xia¹, Wang Jing¹, De Gejirifu¹
Energy Engineering, Vol.117, No.6, pp. 397-411, 2020, DOI:10.32604/EE.2020.011633
Abstract To further study the impact of renewable energy penetration on the technical transformation of distribution networks. Based on the output power characteristics of wind power and photovoltaics, a renewable energy grid-connected capacity model and a distribution network full cost-benefit model were constructed. Based on this, to maximize the comprehensive income of the distribution network and the renewable energy penetration rate, to establish the technical reform optimization model and search for the optimal solution through the improved NSGA-II algorithm. Finally, the effectiveness of the proposed model was verified by setting up three scenarios of simultaneous wind power, grid-connected wind power, grid-connected… More
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Research on Effect of Icing Degree on Performance of NACA4412 Airfoil Wind Turbine
Yuhao Jia¹, Bin Cheng^1,2,*, Xiyang Li^1,2, Hui Zhang^1,2, Yinglong Dong¹
Energy Engineering, Vol.117, No.6, pp. 413-427, 2020, DOI:10.32604/EE.2020.012019
Abstract In order to study the effect of icing on the wind turbine blade tip speed ratio and wind energy utilization coefficient under working conditions, it is important to better understand the growth characteristics of wind turbine blade icing under natural conditions. In this paper, the icing test of the NACA4412 airfoil wind turbine was carried out using the natural low temperature wind turbine icing test system. An evaluation model of icing degree was established, and the influence of wind speed and icing degree on the performance parameters of wind turbines was compared and analyzed. It is shown that icing is… More
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ARTICLE
Investigation of Core Loss Calculation Methods for Nanocrystalline Core in Medium Frequency Range
Yunxiang Guo¹, Cheng Lu^1,2, Feng Yu¹, Liang Hua¹, Xinsong Zhang^1,*
Energy Engineering, Vol.117, No.6, pp. 429-438, 2020, DOI:10.32604/EE.2020.011673
Abstract Nanocrystalline core is often adopted in high-power medium-frequency transformer, whose excitation voltage is usually a rectangular wave with an adjustable duty ratio. In this paper, several kinds of methods are proposed for core loss calculation under non-sinusoidal voltage excitation by modifying the original Steinmetz equation (OSE). Firstly, these correction methods are compared in theory, and their analytical equations under rectangular voltage with an adjustable duty ratio are deduced. Then, a hysteresis loop measurement system is established to measure the core loss density of a nanocrystalline core. Based on the measured results of the core loss density under sinusoidal voltage excitation,… More
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A Subsynchronous Oscillation Suppression Method Based on Self-Adaptive Auto Disturbance Rejection Proportional Integral Control of Voltage Source Converter Based Multi-Terminal Direct Current System with Doubly-Fed Induction Generator-Based Wind Farm Access
Miaohong Su¹, Haiying Dong^1,2,*, Kaiqi Liu¹, Weiwei Zou¹
Energy Engineering, Vol.117, No.6, pp. 439-452, 2020, DOI:10.32604/EE.2020.011805
Abstract A subsynchronous oscillation suppression strategy based on self-adaptive auto disturbance rejection proportional integral controller is proposed for doublyfed induction generator-based wind farm integrated into grid through voltage source converter based multi-terminal direct current. In this strategy, the nonlinear PI controller is constructed by fal function to replace the traditional linear PI controller, and then the tracking differentiator is used to arrange the appropriate transition process in combination with the idea of active disturbance rejection control, and the self-adaptive auto disturbance rejection proportional integral controller is designed. By applying the controller to the inner loop of the converter on the rotor… More
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Accurate Study and Evaluation of Small PV Power Generation System Based on Specific Geographical Location
Lian Zhang^1,2,3,5,*, Zijian Chen², Heng Zhang³, Zenghong Ma⁴, Baowen Cao¹, Lihong Song⁵
Energy Engineering, Vol.117, No.6, pp. 453-470, 2020, DOI:10.32604/EE.2020.013276
Abstract As an important new energy, solar energy has been extensively used in the world and different types of solar energy systems have been used in different fields. The photovoltaic power generation system has obvious advantage and high stability compared with other energy systems. Furthermore, the small-scale photovoltaic power generation system has a wider application in the field of power generation due to the performance of high efficiency. In this paper, the optimization research and system evaluation of small-scale photovoltaic power system have been studied in different areas by simulation and experimental methods. Based on the determination of photovoltaic model system,… More
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Research on Intelligent Energy Storage Control Method with Ethernet Communication
Lu Wang^1,2, Yulong Guo², Jianbin Liang^3,*, Haitao Tian⁴
Energy Engineering, Vol.117, No.6, pp. 471-480, 2020, DOI:10.32604/EE.2020.011131
Abstract The increasingly severe global energy crisis has brought great challenges to the energy field, and renewable energy power generation system has been widely concerned because of its characteristics of green and inexhaustible. However, renewable energy also has some limitations in its specific application, and affects the grid-connected power generation of new energy. In this paper, based on the background of photovoltaic power station, the intelligent energy storage control method for single inverter is put forward to assist a single inverter, and the DC component of fluctuating power is extracted by using the moving average function; furthermore, the intelligent energy storage… More
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Design of Nonlinear Uncertainty Controller for Grid-Tied Solar Photovoltaic System Using Sliding Mode Control
D. Menaga¹, M. Premkumar², R. Sowmya^1,*, S. Narasimman³
Energy Engineering, Vol.117, No.6, pp. 481-495, 2020, DOI:10.32604/EE.2020.013282
（This article belongs to this Special Issue: Advancements in Renewable Energy Systems with AI, Big Data, BlockChain, IoT, and Machine Learning Applications)
Abstract The proposed controller accompanies with different sliding surfaces. To understand maximum power point extraction as opposed to nonlinear uncertainties and unknown disturbance of a grid-connected photovoltaic system to various control inputs (u_d, u_q) is designed. To extract maximum power from a solar array and maintain unity power flow in a grid by controlling the voltage across the dclink capacitor (V_pvdc) and reactive current (i_q). A multiple input-output with multiple uncertainty constraints have considered designing proposed sliding mode controllers to validated their robustness performance. An innovative controller verifies uncertain inputs, constant and changes in irradiances, and temperature of the photo-voltaic system.… More
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Experimental Study on Flow and Heat Transfer Characteristics of Nanofluids in a Triangular Tube at Different Rotation Angles
Cong Qi^1,2,*, Chengchao Wang^1,2, Jinghua Tang^1,2, Dongtai Han²
Energy Engineering, Vol.117, No.2, pp. 63-78, 2020, DOI:10.32604/EE.2020.010433
Abstract Because of the poor thermal performance of ordinary tubes, a triangular tube was used to replace the smooth channel in the heat transfer system, and nanofluids were used to take the place of ordinary fluids as the heat transfer medium. High stability nanofluids were prepared, and an experimental set on flow and heat exchange was established. Effects of triangular tube rotation angles (α = 0°, 30°, 60°) as well as mass fractions of nanofluids (ω = 0.1%, 0.3%, 0.5%) on heat exchange and flow performance were experimentally considered at Reynolds numbers (Re = 800–8000). It was shown that the triangular… More
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Unsteady Natural Convection within an Attic-Shaped Space Subject to Sinusoidal Heat Flux on Inclined Walls
Suvash C. Saha^1,*, Ali M. Sefidan², Atta Sojoudi³
Energy Engineering, Vol.117, No.1, pp. 1-17, 2020, DOI:10.32604/EE.2020.010418
Abstract Free convection inside an attic enclosure in which sinusoidal heat flux applied on the inclined walls and a constant temperature applied on the base wall has been investigated numerically to demonstrate the primary flow characteristics and heat transfer within the attic enclosure over daily routine cycles. To solve the governing equations, the finite volume technique has been utilized. After performing the grid independency and time step size tests, the roles of Rayleigh number (Ra) and the attic aspect ratio (AR) on the unsteady flow structure and heat transfer phenomenon are explained for a constant Prandtl number (0.72) for the air.… More
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Experimental Study on Modal and Harmonic Analysis of Small Wind Turbine Blades Using NACA 63-415 Aerofoil Cross-Section
Ajay Veludurthi¹, Venkateshwarlu Bolleddu^2,*
Energy Engineering, Vol.117, No.2, pp. 49-61, 2020, DOI:10.32604/EE.2020.010666
Abstract This work focused on modal and harmonic analysis of small wind turbine blades taken from the NACA 63415 series. The sandwich structure type composite blade is fabricated from GFRP and epoxy with Uni-vinyl hard foams of different alignments as stiffeners. In this work, the modal and harmonic analysis of different varieties of blades like solid, hallow and rectangular alignment blades is carried out by the finite element method using ANSYS 18.1 software. From Finite Element Analysis, the natural frequencies, amplitudes and mode shapes are obtained. Based on the working principle of wind turbine blades, the boundary conditions are applied. The… More
Views:1137 Downloads:744 Download PDF

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Performance and Cost Analysis of Energy Production from Offshore Wind Turbines
Haytham Ayoub, Ehab Hussein Bani-Hani^*
Energy Engineering, Vol.117, No.1, pp. 41-47, 2020, DOI:10.32604/EE.2020.010412
Abstract Offshore wind turbine is analyzed theoretically and experimentally for improving wind energy harvesting. The energy produced is calculated at different wind speeds. The wind speed curve is generated by measuring the wind speed on daily base for one year. Curves that show the power extraction for experimental study and from the theoretical calculations are generated. The energy production investigation is expanded over a period of 15 years after comparing the annual energy production in theory and practice. The study shows the cost of electricity over the same time period assuming different interest rates. Three time intervals are shown that are… More
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Research on the Measurement and Countermeasure of Coal Overcapacity in China: Based on Panel Data of 25 Provinces in China
Rijia Ding¹, Xingyao Zhou^1,*, Rui Zhang¹, Wanqiu Lu²
Energy Engineering, Vol.117, No.1, pp. 27-39, 2020, DOI:10.32604/EE.2020.010372
Abstract Coal is the main energy source in China. At present, the coal overcapacity is still serious in China. Accurately measuring the degree of China’s coal overcapacity can scientifically resolve the overcapacity, and is the premise of guiding the healthy development of coal industry and energy system. Using the translog cost function and the panel data of coal industry in all provinces of China from 2002 to 2011 and from 2012 to 2016, the research measures and compares the coal production capacity of “golden decade” and “cold winter” in China. The results show that: (1) The change of coal production capacity… More
Views:1098 Downloads:469 Download PDF

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Research on the Influencing Rules of Gas Hydrate Emission Dissipation Coefficient Based on Subspace Spectrum Clustering
Geng Guo^1,*, Leiwen Chen¹, Ji Li², Shu Yan³, Wenxiang Wu⁴, Lingxu Li⁵, Hongda Li⁶
Energy Engineering, Vol.117, No.2, pp. 79-88, 2020, DOI:10.32604/EE.2020.010529
Abstract Featured by high energy density, low combustion pollution and large quantity, natural gas hydrate has become one of the research hotspots in Sanlutian Field of Muri Coalfield since 2008, when China first drilled natural gas hydrate samples in the permafrost area of Qilian Mountains, Qinghai-Tibet Plateau. However, the study on the controlling factors of gas hydrate accumulation is still shallow, which hinders the exploration and development of natural gas hydrate resources. The controlling factors of gas hydrate accumulation mainly include temperature and pressure conditions, gas source conditions, sedimentary conditions and structural conditions, among which structural conditions are the important one.… More
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