Dandan Song^1,*, Lianjun Zhou¹, Ziqi Peng², Senhua Luo², Jun Zhu³

Energy Engineering, Vol.118, No.5, pp. 1439-1452, 2021, DOI:10.32604/EE.2021.015011

Abstract The axial flux permanent magnet (AFPM) generator with double-sided internal stator structure is highly suitable for vertical axis wind turbines due to its high power density. The performance of the AFPM generator with double-sided internal stator structure can be improved by the reasonable design of electromagnetic parameters. To further improve the overall performance of the AFPM generator with double-sided internal stator structure, multivariable (coil width ω_c, permanent magnet thickness h, pole arc coefficient α_p and working air gap l_g) and multi-objective (generator efficiency η, total harmonic distortion of the voltage THD and induced electromotive force amplitude EMF) functional More >

Pinjie Xie^1,*, Ying Zhai¹, Fan Yang^1,2, Zhuowen Mu³, Chao Wang⁴

Energy Engineering, Vol.118, No.5, pp. 1353-1374, 2021, DOI:10.32604/EE.2021.014970

Abstract Electricity productivity is regarded as a major assessment indicator in the design of energy saving policies, given that China has entered a “New Normal” of economic development. In fact, enhancing electricity productivity in an all-round way, as is one of the binding indicators for energy and environmental issues, means that non-growth target of total electric energy consumption in the economic development is feasible. The Gini coefficient, Theil index, and Mean log deviation are utilized to measure regional differences in China’s electricity productivity from 1997 to 2016 in five regions, and conditional β convergence is empirically analyzed… More >

Mingyu Yu¹, Mengyuan Liu¹, Guangqian Luo^1,2,*, Ruize Sun¹, Jingyuan Hu¹, Hailu Zhu¹, Li Zhong³, Lipeng Han³, Xian Li¹, Hong Yao¹

Energy Engineering, Vol.118, No.5, pp. 1277-1286, 2021, DOI:10.32604/EE.2021.014810

Abstract The application of forced mercury oxidation technology would lead to an increase of Hg²⁺ concentration in the flue gas. Although Hg²⁺ can be easily removed in the WFGD, the mercury re-emission in the WFGD can decrease the total removal of mercury from coal-fired power plants. Hence, it is necessary to control Hg²⁺ concentration in the devices before the WFGD. Fly ash adsorbent is considered as a potential alternative for commercial activated carbon adsorbent. However, the adsorption efficiency of the original fly ash is low. Modification procedure is needed to enhance the adsorption performance. In this study, the More >

Doudou Liu^1,*, Liang Qiao^2,3, Feng Zhang⁴, Xueliang Yuan²

Energy Engineering, Vol.118, No.5, pp. 1395-1409, 2021, DOI:10.32604/EE.2021.014697

Abstract The rapid development of urbanization has led to a rapid increase in total energy consumption. The proportion of domestic energy consumption to total energy consumption has gradually increased and has become the major driving force for energy consumption. With the pressure from urbanization and domestic energy consumption, it is necessary to study the impact of urbanization on domestic energy consumption of the regional level and to explore the function paths of these two factors. The findings are helpful to realize sustainable development based on the actual situation analysis, horizontal survey data and statistical yearbook panel… More >

Hui Wang, Haocheng Xu^*, Wenhui Zhao

Energy Engineering, Vol.118, No.5, pp. 1375-1394, 2021, DOI:10.32604/EE.2021.014641

Abstract Under the background of implementing renewable portfolio standards and the ever-improving tradable green certificate scheme, the increasingly environmentally-friendly preference of power users is leading to changes in electricity demand, which, in turn, is driving changes in the decision-making behaviors of various actors in the power supply chain. Based on this, with the goal of pursuing maximum profit, consumer-power-demand functions have been introduced with some consideration of the factors of consumer preference to establish an optimal profit model for each trading subject in non-cooperative states of the power supply chain, under the constraints of meeting renewable More >

Bing Wang^1,2, Kailei Deng¹, Liting He¹, Zhenming Sun^1,*

Energy Engineering, Vol.118, No.5, pp. 1333-1351, 2021, DOI:10.32604/EE.2021.014258

Abstract China has implemented both quantitative and policy incentives for renewable energy development since 2019 and is currently in the policy transition stage. The implementation of renewable portfolio standards (RPSs) is difficult due to the interests of multiple stakeholders, including power generation enterprises, power grid companies, power users, local governments, and the central government. Based on China’s RPS policy and power system reform documents, this research sorted out the core game decision problems of China’s renewable energy industry and established a conceptual game decision model of the renewable energy industry from the perspective of local governments,… More >

Wei Zhang^1,2, Qihui Ling^1,2,*, Qiancheng Zhao^1,2, Hushu Wu³

Energy Engineering, Vol.118, No.5, pp. 1515-1535, 2021, DOI:10.32604/EE.2021.014162

Abstract The condition monitoring and fault diagnosis have been identified as the key to achieving higher availabilities of wind turbines. Numerous studies show that the open-circuit fault is a significant contributor to the failures of wind turbine converter. However, the multiple faults combinations and the influence of wind speed changes abruptly, grid voltage sags and noise interference have brought great challenges to fault diagnosis. Accordingly, concerning the open-circuit fault of converters in direct-driven PMSG wind turbine, a diagnostic method for multiple open-circuit faults is proposed in this paper, which is divided into two tasks: The first… More >

Dan Wu¹, Yanbo Che¹, Wei Li^2,*, Wei He³, Dongyi Li⁴

Energy Engineering, Vol.118, No.5, pp. 1549-1564, 2021, DOI:10.32604/EE.2021.014818

Abstract With the significant progress of the “coal to electricity” project, the electric kiln equipment began to be connected to the distribution network on a large scale, which caused power quality problems such as low voltage, high harmonic distortion rate, and high reactive power loss. This paper proposes a two-stage power grid comprehensive resource optimization configuration model. A multi-objective optimization solution based on the joint simulation platform of Matlab and OpenDSS is developed. The solution aims to control harmonics and optimize reactive power. In the first stage, a multi-objective optimization model is established to minimize the… More >

Yinhe Bu¹, Xingping Zhang^1,2,3,*

Energy Engineering, Vol.118, No.4, pp. 1095-1109, 2021, DOI:10.32604/EE.2021.015893

Abstract With the explosive growth of variable renewable energy, the balance between the supply and demand of the power grid is faced with new challenges. Based on the development experience from typical countries and the state quo in China, this paper further analyzes the system architecture and development trend of demand response under the background of Energy Internet. Five dimensions are considered: Energy Internet platform, demand response application scenarios, system architecture, information technology system construction, and demand response development trend. The results show that the application of the Energy Internet platform can effectively solve the problems More >

Nan Li¹, Ruiyang Xu¹, Caihong Zhang^1,*, Guoping Wu²

Energy Engineering, Vol.118, No.4, pp. 1185-1195, 2021, DOI:10.32604/EE.2021.014741

Abstract An improved radiation transmission and thermal efficiency model for solar ponds has been proposed based on both the Hull Model and Wang/Seyed-Yagoobi Model in this paper. The new model is more accurate to actual measured conditions because multiple reflections and turbidity effects are included. Absorption penetration, thermal conductivity loss and thermal efficiency under different Non-Convective Zone thicknesses are numerically analyzed and thoroughly discussed. The results show that ΔT/I0 plays a critical role for the thermal efficiency of solar pond. Furthermore, it is found through calculation that there is an optimum thickness of the Non-Convective Zone. More >