Bo Yang¹, Zhengxun Guo¹, Jingbo Wang^1,*, Chao Duan², Yaxing Ren³, Yixuan Chen⁴

Energy Engineering, Vol.119, No.5, pp. 1789-1795, 2022, DOI:10.32604/ee.2022.022217

Abstract This article has no abstract. More >

Kittikorn Sasujit^1,*, Nigran Homdoung¹, Nakorn Tippayawong²

Energy Engineering, Vol.119, No.5, pp. 2149-2167, 2022, DOI:10.32604/ee.2022.022069

Abstract Biomass is becoming one of the most popular renewable energy sources, especially from agricultural wastes. These wastes can be gasified and utilized in various industries. This experimental study investigated producer gas generation from densified agricultural fuels such as corncobs, rice husks, wood chips, and oil palm fronds in a 50 kW_th throatless downdraft gasifier. This system produced combustible gases such as H₂, CO, and CH₄, which were utilized as a substitute for diesel fuel in a small diesel engine for power generation. The results showed that the gasifier performs successfully and seems to prefer pellets to briquettes. Producer gas contains 18%–20%… More >

Yuchen Hao^*, Dawei Su, Zhen Lei

Energy Engineering, Vol.119, No.5, pp. 2081-2104, 2022, DOI:10.32604/ee.2022.021342

Abstract Renewable energy sources (RES) such as wind turbines (WT) and solar cells have attracted the attention of power system operators and users alike, thanks to their lack of environmental pollution, independence of fossil fuels, and meager marginal costs. With the introduction of RES, challenges have faced the unit commitment (UC) problem as a traditional power system optimization problem aiming to minimize total costs by optimally determining units’ inputs and outputs, and specifying the optimal generation of each unit. The output power of RES such as WT and solar cells depends on natural factors such as wind speed and solar irradiation… More >

Jiusong Chen^1,*, Dejun Miao¹, Yizong Dai¹, Mojtaba Ghadamyari^2,*

Energy Engineering, Vol.119, No.5, pp. 1985-2003, 2022, DOI:10.32604/ee.2022.021142

Abstract Electric vehicles (EVs) have received special consideration from modern society over the past several years. Although EVs are a fine example of environmentally friendly technology and have many advantages, they relatively increase the electricity demand upon a power grid as well. Therefore, their negative impact on busvoltage and line losses should be analyzed. In this study, the effect of EV loads and their penetration on bus voltage and line losses of an IEEE-33 bussystem has been examined via two scenarios. It is important to mention that the effect of EVs on the rate of air pollution, produced by fossil fuel… More >

Stefanos Tzelepis^*, Kosmas A. Kavadias

Energy Engineering, Vol.119, No.5, pp. 1745-1769, 2022, DOI:10.32604/ee.2022.020984

Abstract

The constant increase in energy demand and related environmental issues have made fuel cells an attractive technology as an alternative to conventional energy technologies. Like any technology, fuel cells face drawbacks that scientific society has been focused on to improve and optimize the overall technology. Thus, the cost is the main inhibitor for this technology due to the significantly high cost of the materials used in catalyst layers. The current discussion mainly focuses on the fundamental electrochemical half-cell reaction of hydrogen oxidation reaction (HOR) and oxygen reduction reaction (ORR) that are taking place in the catalyst layers consisting of Platinum-based… More >

Xiangjian Shi^1,*, Teng Liu², Wei Mu², Jianfeng Zhao¹

Energy Engineering, Vol.119, No.5, pp. 1843-1860, 2022, DOI:10.32604/ee.2022.020787

Abstract A microgrid (MG) refers to a set of loads, generation resources and energy storage systems acting as a controllable load or a generator to supply power and heating to a local area. The MG-generated power management is a central topic for MG design and operation. The existence of dispersed generation (DG) resources has faced MG management with new issues. Depending on the level of exchanges between an MG and the main grid, the MG operation states can be divided into independent or grid-connected ones. Energy management in MGs aims to supply power at the lowest cost for optimal load response.… More >

Haitao Wang^1,2, Yongli Liu^1,*, Bin Shen¹, Mengxuan Ren¹, Qiyuan Shan¹

Energy Engineering, Vol.119, No.5, pp. 2031-2047, 2022, DOI:10.32604/ee.2022.020776

Abstract The goal of this study was to investigate coal quality features and their relationship to coal spontaneous combustion characteristics in multi-seam coal mines to better predict when coal spontaneous combustion is likely to occur. To that end, coal samples of various particle sizes were obtained from five coal seams (Nos. 6, 8, 9, 12 and 20) in the Shuangyashan City Xin’an Coal Mine. The samples were then respectively heated using a temperature programming system to observe and compare similarities and differences in the spontaneous combustion process of different particle sizes in response to rising temperature. The experimental results show, that… More >

Xucheng Chang^1,*, Bing Kong², Yong Li¹, Gaofeng Ren¹, Chao Zhang¹, Zhenghe Wang¹

Energy Engineering, Vol.119, No.5, pp. 1941-1966, 2022, DOI:10.32604/ee.2022.020698

Abstract For purpose of achieving the desired thermal comfort level and reducing the economic cost of maintaining the thermal comfort of green residential building, an energy efficient thermal comfort control strategy based on economic model predictive control (EMPC) for green residential buildings which adopts household heat metering is presented. Firstly, the nonlinear thermal comfort model of heating room is analyzed and obtained. A practical nonlinear thermal comfort prediction model is obtained by using an approximation method. Then, the economic cost function and optimization problem of energy-saving under the necessary thermal comfort requirements are constructed to realize the optimal economic performance of… More >

Jun Zhao¹, Shuguo Gao¹, Yunpeng Liu^2,3, Quan Wang^2,*, Ziqiang Xu², Yuan Tian¹, Lu Sun¹

Energy Engineering, Vol.119, No.5, pp. 1811-1828, 2022, DOI:10.32604/ee.2022.020490

Abstract Aiming at the problem of abnormal data generated by a power transformer on-line monitoring system due to the influences of transformer operation state change, external environmental interference, communication interruption, and other factors, a method of anomaly recognition and differentiation for monitoring data was proposed. Firstly, the empirical wavelet transform (EWT) and the autoregressive integrated moving average (ARIMA) model were used for time series modelling of monitoring data to obtain the residual sequence reflecting the anomaly monitoring data value, and then the isolation forest algorithm was used to identify the abnormal information, and the monitoring sequence was segmented according to the… More >

Jia’an Xie^1,*, Yurong Wang², Guobin Jin³, Mucheng Wu¹

Energy Engineering, Vol.119, No.5, pp. 1797-1809, 2022, DOI:10.32604/ee.2022.020344

Abstract In order to effectively solve the dead-zone and low-precision of T-shaped transmission line fault location, a new T-shaped transmission line fault location algorithm based on phase-angle jump checking is proposed in this paper. Firstly, the 3-terminal synchronous fundamental positive sequence voltage and current phasors are extracted and substituted into the fault branch distance function to realize the selection of fault branch when the fault occurs; Secondly, use the condition of the fundamental positive sequence voltage phasor at the fault point is equal to calculate all roots (including real root and virtual roots); Finally, the phase-angle jump check function is used… More >