  Citation: Hossain, M.S.; Islam, K.Z.; Alharbi, A.G.; Shafiullah, M.; Islam, M.R.; Fekih, A. Optimal Design of a Hybrid Solar PV/BG-Powered Heterogeneous Network. Sustainability 2022, 14, 2201. https://doi.org/10.3390/ su14042201 Academic Editor: Adam Smoli ´ nski Received: 28 December 2021 Accepted: 11 February 2022 Published: 15 February 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). sustainability Article Optimal Design of a Hybrid Solar PV/BG-Powered Heterogeneous Network Md. Sanwar Hossain 1, * , Khondoker Ziaul Islam 2, *, Abdullah G. Alharbi 3 , Md Shafiullah 4 , Md. Rabiul Islam 5 and Afef Fekih 6 1 Department of Electrical and Electronic Engineering, Bangladesh University of Business and Technology, Dhaka 1216, Bangladesh 2 Discipline of Information Technology, Murdoch University, Murdoch, WA 6150, Australia 3 Department of Electrical Engineering, Faculty of Engineering, Jouf University, Sakaka 42421, Saudi Arabia; a.g.alharbi@ieee.org 4 Interdisciplinary Research Center for Renewable Energy and Power Systems, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia; shafiullah@kfupm.edu.sa 5 School of Electrical, Computer and Telecommunications Engineering, University of Wollongong, Sydney, NSW 2522, Australia; mrislam@uow.edu.au 6 Department of Electrical and Computer Engineering, University of Louisiana at Lafayette, Lafayette, LA 70504, USA; afef.fekih@louisiana.edu * Correspondence: sanwar@bubt.edu.bd (M.S.H.); zia.islam@murdoch.edu.au (K.Z.I.) Abstract: The increased penetration of renewable energy sources (RESs) along with the rise in demand for wireless communication had led to the need to deploy cellular base stations powered by locally accessible RESs. Moreover, networks powered by renewable energy sources have the ability to reduce the costs of generating electricity, as well as greenhouse gas emissions, thus maintaining the quality of service (QoS). This paper examines the techno-economic feasibility of developing grid-tied solar photovoltaic (PV)/biomass generator (BG)-powered heterogeneous networks in Bangladesh, taking into account the dynamic characteristics of RESs and traffic. To guarantee QoS, each macro and micro-base station is supplied through a hybrid solar PV/BG coupled with enough energy storage devices. In contrast, pico and femto BSs are powered through standalone solar PV units due to their smaller power rating. A hybrid optimization model for electric renewables (HOMER)-based optimization algorithm is considered to determine the optimum system architecture, economic and environmental analysis. MATLAB-based Monte-Carlo simulations are used to assess the system’s throughput and energy efficiency. A new weighted proportional-fair resource method is presented by trading power consumption and communication latency in non-real-time applications. Performance analysis of the proposed architecture confirmed its energy efficiency, economic soundness, reliability, and environmental friendliness. Additionally, the suggested method was shown to increase the battery life of the end devices. Keywords: HetNet; green communication; cellular network; solar PV; biomass generator; NRT; renewable energy 1. Introduction The telecommunication sector of Bangladesh is growing at an exponential rate due to the rapid increment in mobile subscribers and the ever-increasing data demand. In other words, the nation is entering an era of very dense wireless networks with specialized needs such as tens of Gbps data rates and roughly 10 years of storage lifetime for low-power Internet of Things (IoT) devices [1,2]. The fast and widespread deployment of cellular base stations throughout the world has considerably increased energy consumption, thus depleting fossil fuel reserves and increasing greenhouse emissions (GHG). Furthermore, improved energy efficiency (EE), strong connection, and very low latency are projected Sustainability 2022, 14, 2201. https://doi.org/10.3390/su14042201 https://www.mdpi.com/journal/sustainability