Smart integration of renewable energy resources, electrical, and thermal energy storage in microgrid applications Fatemeh Tooryan a, * , Hamid HassanzadehFard b , Edward R. Collins a , Shuangshuang Jin c , Bahram Ramezani b a Holcombe Department of Electrical and Computer Engineering, Clemson University, USA b Department of Electrical Engineering, Miyaneh Branch, Islamic Azad University, Miyaneh, Iran c School of Computing, Clemson University, USA article info Article history: Received 9 March 2020 Received in revised form 19 August 2020 Accepted 23 August 2020 Available online 1 September 2020 Index Terms: Energy optimization Battery energy storage system Thermal energy storage Renewable energy resources Microgrid system abstract With changes in energy policies to increase renewable energy resources integration, reduce fossil fuel consumption, and mitigate the environmental impact, optimal management of distributed energy re- sources becomes one of the key factors in the design of microgrid systems. This paper presents an op- timum design and operation of a microgrid consisting of wind turbine, photovoltaic array, battery energy storage system, thermal energy storage, fuel cells, and boilers with consideration of electrical, heating and cooling loads. To optimize energy management, the uncertainty of renewable energy resources is considered. Furthermore, the system waste is utilized to produce biogas for boilers to meet heating demands within the system. The optimum energy management problem of distributed energy resources in the microgrid is solved using a Particle Swarm Optimization algorithm. The optimization results are obtained via minimizing the objective function which includes total cost of the system, greenhouse gas emissions, and fuel consumption. The results are shown that there is about a 24.56% reduction in CO 2 emission when the produced heat of FC units are employed. It is observed that the utilization of pro- duced energy from system waste brought down fuel consumption by 7%. The simulation results verify the efficiency and effectiveness of the proposed approach. © 2020 Elsevier Ltd. All rights reserved. 1. Introduction In recent years, an awareness of climate change causes changes in energy policies in most international energy agencies. The best solution for coping with these problems is utilizing Renewable Energy Sources (RESs) which have been widely used to supply the electrical loads and reduce greenhouse gas emission [1]. The Microgrid (MG) that integrates different Distributed Energy Re- sources (DERs) and loads, takes the maximum benefits from RESs and can be operated in both grid-tied and islanded mode [2]. Grid- tied MG exchanges electricity with the main grid whenever it is needed. MG may be a cost-effective option for supplying both heating and electrical demand from the customer’s point of view, and a controllable unit power system operated as a single lump load with a generator from the grid’s management point of view [3]. To mitigate high intermittency and variability of RESs’ power generation, the MG can employ conventional power generation and energy storage technologies to form a hybrid MG [4]. In this paper, an MG consists of Photovoltaic (PV), Wind Turbine (WT), Fuel Cell (FC) units, Battery Energy Storage System (BESS), Thermal Energy Storage System (TESS), and Boilers. Furthermore, the reason for the combination of these resources within an MG is to fulfill electrical, heating, and cooling loads in the system. The technical and eco- nomic constraints of MG should be considered to satisfy the load and generation balance. Many studies have been focused on designing, planning, and optimization of a hybrid MG employing various strategies. Barto- lucci et al. compared two different control approaches, model predictive control, and rule-based control strategies for energy management strategy in an MG system to reduce Carbon dioxide (CO 2 ) emissions and to increase penetration of RESs [5]. In Ref. [6], two configurations of integrating PV and geothermal energy were used for air cooling and heating by sending the cold and warm air to the earth during winter and summer seasons. Saffari et al. * Corresponding author. E-mail addresses: ftoorya@g.clemson.edu (F. Tooryan), hamid.hassanzadehfard@ m-iau.ac.ir (H. HassanzadehFard), collins@clemson.edu (E.R. Collins), jin6@clemson. edu (S. Jin), ramezani@m-iau.ac.ir (B. Ramezani). Contents lists available at ScienceDirect Energy journal homepage: www.elsevier.com/locate/energy https://doi.org/10.1016/j.energy.2020.118716 0360-5442/© 2020 Elsevier Ltd. All rights reserved. Energy 212 (2020) 118716