Cellular network operators are actively expanding network coverage and capacity by deploying additional base-stations to provide mobile services to customers in rural areas. The increasing deployment of cellular base-stations has increased the power consumption, energy cost, and associated adverse environmental impact. This paper addresses the feasibility of using renewable energy sources to power off-grid rural 4G/5G cellular base-stations based on Kuwait’s solar irradiance and wind potentials. More importantly, a hybrid renewable energy system will be designed and modeled to meet realistic energy demands of remote base-stations and determine the optimum size of the hybrid system components. Particularly, the hybrid off-grid system may incorporate wind turbines (WTs), photovoltaic (PV) solar panels, converters, a battery bank (BB), and a back-up diesel generator (DG). Two remote cell-sites are considered, namely: (1) Jal-Alayah and (2) Wafra, where the Jal-Alayah cell-site is characterized with higher average wind speed (and wind potential), while the Wafra cell-site has higher average clearness index and solar irradiance. Various hybrid PV/wind electric system (HPWES) configurations are modeled and simulated via HOMER software, with the aim of determining the optimal configuration—in terms of net present cost (NPC)—in each cell-site. Specifically, the simulations have revealed that the WT-BB configuration is the most economical at the Jal-Alayah cell-site while requiring minimal land area and ensuring 100% renewable energy and zero CO${}_2$ emissions. This configuration is followed by the PV-DG-BB and PV-WT-DG-BB configurations, where the latter configuration incurs a marginal increase in the NPC than the former but with less land area. On the other hand, the PV-BB configuration is the most cost-effective in the Wafra cell-site; however, in the scenario of limited land area, then the PV-DG-BB configuration can be used but at the expense of slight increase in the NPC and CO${}_2$ emissions. This study confirms that utilizing renewable energy sources in two rural areas in Kuwait can be extremely effective in replacing conventional DG-powered base-stations, while minimizing the NPC and CO${}_2$ emissions.

With the rapidly evolving mobile technologies, the number of cellular base stations (BSs) has significantly increased to meet the explosive demand for mobile services and applications. In turn, this has significantly increased the capital and operational expenses, due to the increased electricity prices and energy consumption. To generate electricity, power plants mainly rely on fossil fuels, which are non-renewable energy resources. As a result, CO${}_2$ emissions also increase, which adversely affect health and environment. For wireless access technologies and cellular networks, BSs are the largest power consumer, and the network energy consumption is mainly dominated by the network infrastructure, which makes the telecommunications sector liable for energy consumption as well as CO${}_2$ emissions around the globe. Alternatively, solar energy is considered as an eco-friendly and economically attractive solution, due to its cost-effectiveness and sustainability. In this paper, the potentials of photovoltaic (PV) solar power to energize cellular BSs in Kuwait are studied, with the focus on the design, implementation, and analysis of off-grid solar PV systems. Specifically, system components, such as the number of PV panels, batteries, and converters needed for the design are determined and evaluated via HOMER software, with the focus on minimizing the net present cost (NPC). A comparison between various PV, diesel generator (DG), and battery bank (BB) system configurations is also performed. Moreover, a comparison of system deployment area will be presented for different PV panels that have different output power and panel sizes, in addition to utilizing a solar tracking system. It is revealed that utilizing a hybrid system configuration (i.e., PV-DG-BB) decreases fuel consumption per year by almost 95% in comparison to the conventional DG-only based electric systems. Not only that, but utilizing a pure off-grid solar PV system (i.e., PV-BB) can significantly reduce the total NPC while completely eliminating CO${}_2$ emissions; however, at the expense of more land.

This paper investigates the maximum photovoltaic (PV) penetration limits on both overhead lines and underground cables medium voltage radial distribution system. The maximum PV penetration limit is estimated considering both bus voltage limit (1.05 p.u.) and feeder current ampacity (1 p.u.). All factors affect the max PV penetration limit are investigated in detail. Substation voltage, load percentage, load power factor, and power system frequency (50 Hz or 60 Hz) are analyzed. The maximum PV penetration limit associated with overhead lines is usually higher than the value associated with the underground cables for high substation voltage (substation voltage = 1.05 and 1.04 p.u.). The maximum PV penetration limit decreases dramatically with low load percentage for both feeder types but still the overhead lines accept PV plant higher than the underground cables. Conversely, the maximum PV penetration increases with load power factor decreasing and the overhead lines capability for hosting PV plant remains higher than the capability of the underground cables. This paper proved that the capability of the 60-Hz power system for hosting the PV plant is higher than the capability of 50 Hz power system. MATLAB software has been employed to obtain all results in this paper. The Newton-Raphson iterative method was the used method to solve the power flow of the investigated systems.

Performance issues may arise with the increased integration of renewable energy sources (RESs). In this paper, ETAP analysis tools are used to examine IEEE 9-bus system by integrating various RESs, including photovoltaic (PV) panels, two types of wind turbines (WTs), and hybrid configurations. To assess steady-state performance, the operating conditions are varied including changes in RES types, penetration levels, power factors, and topology. Improved voltage stability and reduced power losses can be attained by implementing optimal operation techniques and utilizing RESs with controllable volt/var capabilities to adjust the power factor. Further, fault analysis at different buses reveals that the presence of RESs can significantly alter fault currents, potentially causing maloperation of protective devices. When RESs are distributed among multiple buses, fault currents in the lines close to RESs increase while those in distant lines decrease by 50% in certain cases. Additionally, the behavior of the system under transient events–including faults, loss of generation units, and sudden load changes–is examined. The findings indicate that while RES integrating improves the overall stability, notable differences exist between PV- and wind-based sources. Specifically, the power system may overcompensate for the lack of inertia-support in PV-based sources, leading to a speed drop below the nominal value of the swing bus. Therefore, adaptive protection schemes and inertia-support capabilities are required when RESs are integrated into existing grids to provide accurate protection operations and stability support particularly during major disturbances.