Kaicheng Liu^1,3, Chen Liang², Naiyue Wu^1,3, Xiaoyang Dong², Hui Yu^1,*

Energy Engineering, Vol.121, No.9, pp. 2621-2637, 2024, DOI:10.32604/ee.2024.050001 - 19 August 2024

Abstract This paper presents a novel approach to economic dispatch in smart grids equipped with diverse energy devices. This method integrates features including photovoltaic (PV) systems, energy storage coupling, varied energy roles, and energy supply and demand dynamics. The system model is developed by considering energy devices as versatile units capable of fulfilling various functionalities and playing multiple roles simultaneously. To strike a balance between optimality and feasibility, renewable energy resources are modeled with considerations for forecasting errors, Gaussian distribution, and penalty factors. Furthermore, this study introduces a distributed event-triggered surplus algorithm designed to address the More >

Anggara Ridho Putra¹, Apri Heri Iswanto^1,*, Arif Nuryawan¹, Saptadi Darmawan², Elvara Windra Madyaratri², Widya Fatriasari², Lee Seng Hua³, Petar Antov^4,*, Harisyah Manurung¹, Ade Pera Amydha Sudrajat Herawati Pendi²

Journal of Renewable Materials, Vol.12, No.6, pp. 1103-1123, 2024, DOI:10.32604/jrm.2024.051077 - 02 August 2024

Abstract The increased valorization of renewable and cost-effective lignocellulosic feedstocks represents a viable, sustainable, and eco-friendly approach toward the production of biopellets as alternative energy sources. The aim of this research work was to investigate and evaluate the feasibility of using various lignocellulosic raw materials, i.e., raru (Cotylelobium melanoxylon), mangrove (Rhizophora spp.), sengon (Paraserianthes falcataria), kemenyan toba (Styrax sumatrana), oil palm (Elaeis guineensis), manau rattan (Calamus manan), and belangke bamboo (Gigantochloa pruriens) for manufacturing biopellets with different particle sizes. The raw materials used were tested for their moisture content, specific gravity, ash, cellulose, and lignin content. In addition, thermal analyses, i.e., calorific values,… More >

Chia-Nan Wang, Thuy-Duong Thi Pham^*, Nhat-Luong Nhieu

Energy Engineering, Vol.121, No.8, pp. 2039-2064, 2024, DOI:10.32604/ee.2024.050224 - 19 July 2024

Abstract Geothermal energy is considered a renewable, environmentally friendly, especially carbon-free, sustainable energy source that can solve the problem of climate change. In general, countries with geothermal energy resources are the ones going through the ring of fire. Therefore, not every country is lucky enough to own this resource. As a country with 117 active volcanoes and within the world’s ring of fire, it is a country whose geothermal resources are estimated to be about 40% of the world’s geothermal energy potential. However, the percentage used compared to the geothermal potential is too small. Therefore, this… More >

Yirui Li¹, Dongliang Xiao^1,3,*, Haoyong Chen¹, Weijun Cai¹, Josue Campos do Prado²

Energy Engineering, Vol.121, No.8, pp. 2093-2127, 2024, DOI:10.32604/ee.2024.049232 - 19 July 2024

Abstract Currently, both regulated and deregulated power trading exist in China’s power system, which has caused imbalanced funds in the electricity market. In this paper, a simulation analysis of the electricity market with wind energy resources is conducted, and the calculation methods of unbalanced funds are investigated systematically. In detail, the calculation formulas of unbalanced funds are illustrated based on their definition, and a two-track electricity market clearing model is established. Firstly, the concept of the dual-track system is explained, and the specific calculation formulas of various types of unbalanced funds are provided. Next, considering the More >

Ali S. Alghamdi^1,*, Mohamed A. Zohdy², Saad Aldoihi^3,4

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.2, pp. 1339-1370, 2024, DOI:10.32604/cmes.2024.048839 - 20 May 2024

Abstract In the contemporary era, the global expansion of electrical grids is propelled by various renewable energy sources (RESs). Efficient integration of stochastic RESs and optimal power flow (OPF) management are critical for network optimization. This study introduces an innovative solution, the Gaussian Bare-Bones Levy Cheetah Optimizer (GBBLCO), addressing OPF challenges in power generation systems with stochastic RESs. The primary objective is to minimize the total operating costs of RESs, considering four functions: overall operating costs, voltage deviation management, emissions reduction, voltage stability index (VSI) and power loss mitigation. Additionally, a carbon tax is included in… More >

Aadel M. Alatwi^1,2, Abualkasim Bakeer³, Sherif A. Zaid^1,*, Ibrahem E. Atawi¹, Hani Albalawi^1,4, Ahmed M. Kassem⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.2, pp. 1807-1830, 2024, DOI:10.32604/cmes.2024.048521 - 20 May 2024

Abstract An autonomous microgrid that runs on renewable energy sources is presented in this article. It has a superconducting magnetic energy storage (SMES) device, wind energy-producing devices, and an energy storage battery. However, because such microgrids are nonlinear and the energy they create varies with time, controlling and managing the energy inside them is a difficult issue. Fractional-order proportional integral (FOPI) controller is recommended for the current research to enhance a standalone microgrid’s energy management and performance. The suggested dedicated control for the SMES comprises two loops: the outer loop, which uses the FOPI to regulate… More >

Yongjiang Zhao, Haoyi Zhong, Chang Cyoon Lim^*

CMC-Computers, Materials & Continua, Vol.79, No.1, pp. 449-471, 2024, DOI:10.32604/cmc.2024.048771 - 25 April 2024

Abstract This paper examines the difficulties of managing distributed power systems, notably due to the increasing use of renewable energy sources, and focuses on voltage control challenges exacerbated by their variable nature in modern power grids. To tackle the unique challenges of voltage control in distributed renewable energy networks, researchers are increasingly turning towards multi-agent reinforcement learning (MARL). However, MARL raises safety concerns due to the unpredictability in agent actions during their exploration phase. This unpredictability can lead to unsafe control measures. To mitigate these safety concerns in MARL-based voltage control, our study introduces a novel… More >

Mousumi Basu¹, Chitralekha Jena², Baseem Khan^3,4,*, Ahmed Ali⁴

Energy Engineering, Vol.121, No.4, pp. 849-867, 2024, DOI:10.32604/ee.2024.043294 - 26 March 2024

Abstract In the restructured electricity market, microgrid (MG), with the incorporation of smart grid technologies, distributed energy resources (DERs), a pumped-storage-hydraulic (PSH) unit, and a demand response program (DRP), is a smarter and more reliable electricity provider. DER consists of gas turbines and renewable energy sources such as photovoltaic systems and wind turbines. Better bidding strategies, prepared by MG operators, decrease the electricity cost and emissions from upstream grid and conventional and renewable energy sources (RES). But it is inefficient due to the very high sporadic characteristics of RES and the very high outage rate. To More >

Yan Shi¹, Wenjie Li¹, Gongbo Fan^2,*, Luxi Zhang¹, Fengjiu Yang¹

Energy Engineering, Vol.121, No.2, pp. 461-482, 2024, DOI:10.32604/ee.2023.043835 - 25 January 2024

Abstract Addressing the insufficiency in down-regulation leeway within integrated energy systems stemming from the erratic and volatile nature of wind and solar renewable energy generation, this study focuses on formulating a coordinated strategy involving the carbon capture unit of the integrated energy system and the resources on the load storage side. A scheduling model is devised that takes into account the confidence interval associated with renewable energy generation, with the overarching goal of optimizing the system for low-carbon operation. To begin with, an in-depth analysis is conducted on the temporal energy-shifting attributes and the low-carbon modulation… More >

Qin Yao, Yida Zeng^*, Qingui Jia

Energy Engineering, Vol.121, No.1, pp. 221-241, 2024, DOI:10.32604/ee.2023.041028 - 27 December 2023

Abstract In recent years, switched inductor (SL) technology, switched capacitor (SC) technology, and switched inductor-capacitor (SL-SC) technology have been widely applied to optimize and improve DC-DC boost converters, which can effectively enhance voltage gain and reduce device stress. To address the issue of low output voltage in current renewable energy power generation systems, this study proposes a novel non-isolated cubic high-gain DC-DC converter based on the traditional quadratic DC-DC boost converter by incorporating a SC and a SL-SC unit. Firstly, the proposed converter’s details are elaborated, including its topology structure, operating mode, voltage gain, device stress,… More >