• Energy Research

A hybrid solar photovoltaic (PV)/biomass generator (BG) energy-trading framework between grid supply and base stations (BSs) is proposed in this article to address the power crisis of the utility grid, to enhance energy self-reliance, and to downsize the cost. The optimal size, technical criteria, energy generation, and different types of costs have been evaluated considering the dynamic behavior of solar radiation, traffic arrival intensity, and average biomass energy potential. Additionally, the wireless network performance in terms of total achievable throughput, spectral efficiency (SE), and energy efficiency (EE) are extensively examined using the MATLAB-based Monte-Carlo simulations taking multipath fading, system bandwidth, transmission power, and inter-cell interference (ICI) into consideration. The numerical results demonstrate that the energy-trading facility can achieve net present cost (NPC) and greenhouse gas saving up to 3.20% and 65.8%, respectively. In the end, the performance of the hybrid solar PV/BG system has been thoroughly compared with the standalone solar PV, hybrid PV/wind turbine (WT), and hybrid PV/diesel generator (DG) systems under on-grid and off-grid configurations for benchmarking.

In a power system, transmission reliability margin (TRM) is a key factor that determines the available transmission capability (ATC) ensuring the secure operation of the transmission network during the occurrence of uncertainties. Before transmitting available power through the network, it is necessary to know the secure margin. The secure margin determines whether it’s safe for transmission or not. The exact calculation of the transmission reliability margin is quite challenging due to the random disturbances in the transmission network. This paper introduces an effective technique for determining the TRM by AC load flow, considering the available transmission capability and sensitivity of three distinct system parameters such as load, transmission line impedance, and bus voltage magnitude. Numerical results demonstrate that the proposed technique is an attractive solution for calculating the ATC, sensitivity with respect to ATC, and TRM considering the effect of system parameters. The whole process is done for the standard IEEE-6 bus system considering multi-transactions. Finally, the calculated TRM values are compared with the existing techniques for justifying the effectiveness of the proposed technique.

Due to the technological revolution and higher user data demand, the telecommunication industry is expanding at an exponential rate. Fulfilling the increasing demand of energy for the rising cellular networks has become a great challenge to the network operators because of the limited reservation of fuel energy sources and the growing concern about global warming. Energy harvesting (EH) from renewable energy sources (RES) has become an overwhelming initiative to minimize energy deficiency and carbon footprints. This paper investigates the feasibility of solar photovoltaic (PV) and biomass resources based hybrid supply systems for powering the off-grid Long Term Evolution (LTE) cellular macrocell base stations (BSs) in Bangladesh focusing the technical, economic and environmental issues. In addition, the green energy sharing technique has been incorporated via a low resistive path for optimal use of RES. The proposed system has enough potential to achieve long term sustainability and reduction of pollution rates by fulfilling the future energy demand of BS. In this work, Hybrid Optimization Model for Electric Renewables (HOMER) simulation-based feasibility analysis is used to assess the optimal system, energy production, total net present cost (NPC), cost of electricity (COE) and greenhouse gas (GHG) emission depending on different system parameters. Furthermore, the performance of the network has been evaluated in terms of throughput and energy efficiency using Matlab-based Monte Carlo simulations. Results demonstrate that the proposed hybrid renewable energy powered BSs would be a reliable and longer-lasting green solution for the telecom sector while maintaining the quality of service (QoS). Finally, an extensive comparison with other systems has also been done to justify network validity.

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.

Hydrogen has received tremendous global attention as an energy carrier and an energy storage system. Hydrogen carrier introduces a power to hydrogen (P2H), and power to hydrogen to power (P2H2P) facility to store the excess energy in renewable energy storage systems, with the facts of large-scale storage capacity, transportability, and multiple utilities. This work examines the techno-economic feasibility of hybrid solar photovoltaic (PV)/hydrogen/fuel cell-powered cellular base stations for developing green mobile communication to decrease environmental degradation and mitigate fossil-fuel crises. Extensive simulation is carried out using a hybrid optimization model for electric rnewables (HOMER) optimization tool to evaluate the optimal size, energy production, total production cost, per unit energy production cost, and emission of carbon footprints subject to different relevant system parameters. In addition, the throughput, and energy efficiency performance of the wireless network is critically evaluated with the help of MATLAB-based Monte-Carlo simulations taking multipath fading, system bandwidth, transmission power, and inter-cell interference (ICI) into consideration. Results show that a more stable and reliable green solution for the telecommunications sector will be the macro cellular basis stations driven by the recommended hybrid supply system. The hybrid supply system has around 17% surplus electricity and 48.1 h backup capacity that increases the system reliability by maintaining a better quality of service (QoS). To end, the outcomes of the suggested system are compared with the other supply scheme and the previously published research work for justifying the validity of the proposed system.

With the unprecedented augmentation of mobile communications and the advancement of new technologies, energy efficiency (EE) has developed a severe apprehension of maintaining the profitability of telecom operators by means of reducing the operational expenditure with minimum atmospheric deterioration as well. Base stations (BSs) are the prime energy consumer in the telecom sector. Therefore, reducing the energy consumption of BSs in the cellular networks has recently become a great concern by the telecom operators and researchers. As a consequence, attempts have been taken behind reducing BS energy consumption and to find expedient ways for better EE. In this paper, we propose renewable energy powered cloud radio access network (C-RAN) architecture for achieving long term sustainable green cellular networks. Several performance metrics under the telecommunication system namely equipment level and network-level are investigated in the design framework aiming to enhance overall EE. Moreover, MATLAB based Monte-Carlo simulations have been accomplished for checking out EE performance of the introduced network fluctuating system criterions for example transmission bandwidth, the number of the transceiver, solar module capacity, etc. in the context of realistic traffic intensity. Analytical outcomes validate the performance of the recommended system over the conventional one.

With the proliferation of cellular networks, the ubiquitous availability of new-generation multimedia devices, and their wide-ranging data applications, telecom network operators are increasingly deploying the number of cellular base stations (BSs) to deal with unprecedented service demand. The rapid and radical deployment of the cellular network significantly exerts energy consumption and carbon footprints to the atmosphere. The ultimate objective of this work is to develop a sustainable and environmentally-friendly cellular infrastructure through compelling utilization of the locally available renewable energy sources (RES) namely solar photovoltaic (PV), wind turbine (WT), and biomass generator (BG). This article addresses the key challenges of envisioning the hybrid solar PV/WT/BG powered macro BSs in Bangladesh considering the dynamic profile of the RES and traffic intensity in the tempo-spatial domain. The optimal system architecture and technical criteria of the proposed system are critically evaluated with the help of HOMER optimization software for both on-grid and off-grid conditions to downsize the electricity generation cost and waste outflows while ensuring the desired quality of experience (QoE) over 20 years duration. Besides, the green energy-sharing mechanism under the off-grid condition and the grid-tied condition has been critically analyzed for optimal use of green energy. Moreover, the heuristic algorithm of the load balancing technique among collocated BSs has been incorporated for elevating the throughput and energy efficiency (EE) as well. The spectral efficiency (SE), energy efficiency, and outage probability performance of the contemplated wireless network are substantially examined using Matlab based Monte–Carlo simulation under a wide range of network configurations. Simulation results reveal that the proper load balancing technique pledges zero outage probability with expected system performance whereas energy cooperation policy offers an attractive solution for developing green mobile communications employing better utilization of renewable energy under the proposed hybrid solar PV/WT/BG scheme.

The heterogeneous network (HetNet) is a specified cellular platform to tackle the rapidly growing anticipated data traffic. From a communications perspective, data loads can be mapped to energy loads that are generally placed on the operator networks. Meanwhile, renewable energy-aided networks offer to curtailed fossil fuel consumption, so to reduce the environmental pollution. This paper proposes a renewable energy based power supply architecture for the off-grid HetNet using a novel energy sharing model. Solar photovoltaics (PV) along with sufficient energy storage devices are used for each macro, micro, pico, or femto base station (BS). Additionally, a biomass generator (BG) is used for macro and micro BSs. The collocated macro and micro BSs are connected through end-to-end resistive lines. A novel-weighted proportional-fair resource-scheduling algorithm with sleep mechanisms is proposed for non-real time (NRT) applications by trading-off the power consumption and communication delays. Furthermore, the proposed algorithm with an extended discontinuous reception (eDRX) and power saving mode (PSM) for narrowband internet of things (IoT) applications extends the battery lifetime for IoT devices. HOMER optimization software is used to perform optimal system architecture, economic, and carbon footprint analyses while the Monte-Carlo simulation tool is used for evaluating the throughput and energy efficiency performances. The proposed algorithms are validated through the practical data of the rural areas of Bangladesh from which it is evident that the proposed power supply architecture is energy-efficient, cost-effective, reliable, and eco-friendly.