Ruaa H. Abbas¹, A. Kadhim^1,*, Azhar M. Haleem²

Journal of Renewable Materials, Vol.11, No.5, pp. 2109-2123, 2023, DOI:10.32604/jrm.2023.025112 - 13 February 2023

Abstract Copper oxide nanoparticles (CuO NPs) were synthesised with laser ablation of a copper sheet immersed in deionized water (DW), cetrimonium bromide (CTAB), and sodium dodecyl sulphate (SDS), respectively. The target was irradiated with a pulsed Nd: YAG laser at 1064 nm, 600 mJ, a pulse duration of 10 ns, and a repetition rate of 5 Hz. The CuO NPs colloidal were analyzed using UV–Vis spectroscopy, the Fourier transform infrared (FTIR) spectrometer, zeta potential (ZP), X-ray diffraction (XRD), transmission electron microscope (TEM) and field emission scanning electron microscopy (FESEM). The absorption spectra of CuO NPs colloidal… More >

Guodong Zeng¹, Chao Li^1,*, Yang Fang¹, Hongming Huang^1,2, Hao Li^1,3, Yishen Xu¹

Journal of Renewable Materials, Vol.11, No.5, pp. 2453-2467, 2023, DOI:10.32604/jrm.2023.025871 - 13 February 2023

Abstract For evaluating the water stability of hot-mixed renewable asphalt mixture (HRM), the traditional methods are all tested under still water conditions. Except for damage in still water conditions, the hydrodynamic pore pressure generated by the tire driving on the surface water has a great impact. Thus, the RAP contents of the HRMs were designed at 0%, 30%, 45% and 60% with AC-25 gradation. Then, the self-designed evaluation methods of water stability and dynamic modulus were studied. Finally, the mechanism of the influence of hydrodynamic pore pressure damage on HRMs was studied. The results show that… More >

Yafei Hu^1,2, Keqing Li^1,2, Lujing Zheng³, Bin Han^1,2,*

Journal of Renewable Materials, Vol.11, No.5, pp. 2491-2511, 2023, DOI:10.32604/jrm.2023.025129 - 13 February 2023

Abstract Tailings known as solid waste are generated by the mining industry. The development of tailings as wet shotcrete aggregates has significant economic and environmental benefits. The fine particle size of the tailings results in a large consumption of traditional cement as a cementitious material and insignificant improvement in strength. Therefore, a composite cementitious system of cement and solid waste resources (fly ash and slag powder) is explored for this study. In this paper, the response surface methodology (RSM) is used to optimize the experimental design and a multivariate nonlinear response model with cement, fly ash… More >

Junhui Li^1,*, Jinxin Zhong¹, Kailiang Wang¹, Yu Luo¹, Qian Han², Jieren Tan²

Energy Engineering, Vol.120, No.4, pp. 869-884, 2023, DOI:10.32604/ee.2023.021320 - 13 February 2023

Abstract In the process of wind power, coal power, and energy storage equipment participating in the operation of industrial microgrids, the stable operation of wind-storage industrial microgrids is guaranteed by considering demand response technology and user satisfaction. This paper firstly sorts out the status quo of microgrid operation optimization, and determines the main requirements for user satisfaction considering three types of load characteristics, demand response technology, power consumption benefit loss, user balance power purchase price and wind power consumption evaluation indicators in the system. Secondly, the operation architecture of the windstorage industrial microgrid is designed, and… More >

Saurabh Awasthi^*, Gagan Singh, Nafees Ahamad

Energy Engineering, Vol.120, No.4, pp. 811-829, 2023, DOI:10.32604/ee.2023.026863 - 13 February 2023

Abstract A distributed generation system (DG) has several benefits over a traditional centralized power system. However, the protection area in the case of the distributed generator requires special attention as it encounters stability loss, failure re-closure, fluctuations in voltage, etc. And thereby, it demands immediate attention in identifying the location & type of a fault without delay especially when occurred in a small, distributed generation system, as it would adversely affect the overall system and its operation. In the past, several methods were proposed for classification and localisation of a fault in a distributed generation system.… More >

Xiaomei Lin¹, Samuel Bimenyimana^2,*, Chen Wang², Godwin Norense Osarumwensa Asemota^3,4, Jeanne Paula Ihirwe⁵, Aphrodis Nduwamungu³, Etienne Ntagwirumugara⁶, Athanase Gace⁶, Changfu Yuan⁷, Yaowen Chen⁷, Changtai Li⁸, Shilpi Bora⁹, YiYi Mo¹⁰, Jiyu Lai¹¹, Mabao Wu⁷, Yong Tang¹², Merit M. Huang¹³

Energy Engineering, Vol.120, No.4, pp. 791-810, 2023, DOI:10.32604/ee.2023.026746 - 13 February 2023

Abstract Renewable energy exploitation is among the development strategies set by the government of Rwanda on the roadmap to 2023/2024 universal electricity access and the United Nations plans by 2030. Numerous previous studies on clean energy technologies in Rwanda have mostly focused on households’ usage but there are currently no studies describing the feasibility of clean energy technologies for financial institutions. The skepticism on renewable energy in Africa was previously reported by some personnel. Having realized that most SACCOs (Savings and Credit Co-Operatives) in Rwanda use diesel technology for backup/emergency electricity supply, taking consideration of abundant… More >

Ahmed Mohamed Ragab^1,*, Abdelhalim Abdelnaby Zekry², Ashraf Yahia Hassan¹

Energy Engineering, Vol.120, No.4, pp. 885-910, 2023, DOI:10.32604/ee.2023.026425 - 13 February 2023

Abstract Accurate PV system simulators are implemented with expensive software platforms using paid irradiance data. The main purpose of this paper is to develop and validate a PV system simulator, beginning with a solar cell parameter extraction model, then test and validate long-term Irradiance data using free online source (Typical Meteorological Year TMY in (PVGIS) European website), and finally building full solar generator simulator to run in working real conditions. Comparing results with Accurate Paid PV simulators (which use the Muneer model) showed good accuracy of the proposed simulator. Work flow starts with the Irradiance model’s… More >

Shafiqur Rehman^1,*, Hilal H. Nuha², Ali Al Shaikhi³, Satria Akbar², Mohamed Mohandes^1,3

Energy Engineering, Vol.120, No.4, pp. 775-789, 2023, DOI:10.32604/ee.2023.026185 - 13 February 2023

Abstract An accurate vertical wind speed (WS) data estimation is required to determine the potential for wind farm installation. In general, the vertical extrapolation of WS at different heights must consider different parameters from different locations, such as wind shear coefficient, roughness length, and atmospheric conditions. The novelty presented in this article is the introduction of two steps optimization for the Recurrent Neural Networks (RNN) model to estimate WS at different heights using measurements from lower heights. The first optimization of the RNN is performed to minimize a differentiable cost function, namely, mean squared error (MSE),… More >

Tingxia Ma¹, Longyao Zhang¹, Lin Wang^1,*, Jinqiang Wu², Wenying Hui², Cheng Yu³

Energy Engineering, Vol.120, No.4, pp. 911-930, 2023, DOI:10.32604/ee.2023.026002 - 13 February 2023

Abstract Hydrogen energy is a crucial carrier for the growth of the energy system and its low-carbon transformation. Using natural gas as a carrier of hydrogen transport and the natural gas pipeline network for transportation is a significant step toward realizing large-scale and long-distance hydrogen transport. Hydrogen-mixed natural gas is mainly separated into hydrogen and natural gas by physical methods at present. High purity of hydrogen recovery, but the recovery rate is low. At the same time, compared with natural gas, liquefied natural gas is more economical and flexible. This study analyzes three typical cryogenic separation… More >

Yan Wang¹, Zhicheng Ma², Jinping Zhang², Qiang Zhou², Ruiping Zhang¹, Haiying Dong^1,*

Energy Engineering, Vol.120, No.4, pp. 949-963, 2023, DOI:10.32604/ee.2023.025668 - 13 February 2023

Abstract Because of the randomness of wind power and photovoltaic (PV) output of new energy bases, the problem of peak regulation capability and voltage stability of ultra-high voltage direct current (UHVDC) transmission lines, we proposed an optimum allocation method of installed capacity of the solar-thermal power station based on chance constrained programming in this work. Firstly, we established the uncertainty model of wind power and PV based on the chance constrained planning theory. Then we used the K-medoids clustering method to cluster the scenarios considering the actual operation scenarios throughout the year. Secondly, we established the… More >