The Effect of Economic and Environmental Parameters on the Optimality of Sustainable Hybrid Energy Systems

An effective sizing and sensitivity analysis of a hybrid renewable energy system for household, multi-media and rural healthcare centres power supply: A case study of Kaele, Cameroon

Middle East has significant potential for independent solar and wind power generation due to its vast land area and dispersed settlements. Enhancing the standard of living in remote areas and meeting the increasing demand for healthcare services worldwide are crucial objectives. Finding the most reliable and affordable method of supplying energy and clean water to rural healthcare institutions is the main goal of the research. The aim of this research is to evaluate the financial and environmental impacts of employing a hybrid energy system to supply power to a clinic in Rijal Almaa, Saudi Arabia. Utilizing the HOMER software, the investigation determined that the most efficient hybrid configuration includes 360 batteries, a 25 kW DG, a 2 kW wind turbine, 33.3 kW of solar panels, and an 18.4 kW converter. The NPC (Net Present Cost) associated with this optimized system amounts to $109 307, while its COE is 0.103 $/kWh. It was found that this efficient system necessitates an initial capital outlay of $72 281, coupled with an annual operational expense of $2361. The renewable fraction (RF) of 84.7%, excess electricity generation of 8.81%, and fuel consumption of 4135 L/yr are notable features of the system. The system also exhibits the lowest annual CO2 emissions at 10825 kg/yr, indicating a positive environmental impact. The findings can be applied globally, particularly in hot, arid regions. The analysis suggests that reducing the costs of hybrid solar panels, DG, wind turbine, and battery systems could significantly reduce overall costs, making them a feasible solution for developing nations.

This study presents a detailed feasibility analysis of technical and financial assessment for grid-connected Hybrid Renewable Energy System (HRES) configurations by including grid-only, HRES-only and grid-HRES at four different provinces in the Kingdom of Saudi Arabia (KSA), namely; (Al Baha University, University of Jeddah, Prince Sattam Bin Abdulaziz University, and Tabuk University). The objective of this paper is to search the possibility of supplying the load demand with the optimum system that has the lowest net present cost (NPC) and greenhouse emission CO2. The simulation results show that NPC of a proposed grid/PV system, at the current grid’s tariff, is more sufficient than other configurations with a result in a renewable fraction of more than 50%, a payback time of 17 years, and 54.3% reduction in CO2. The results also show that the integration of 62 kW PV array with the main grid is the best configuration that leads to the minimum cost of energy (COE) of 0.0688 $/kWh and the sell back energy of 9.16% of total energy consumption at Al Baha University. Besides, optimization modeling addresses that HRES-only system can supply the full load demand without power shortage (<0.1%) with a major contribution from solar PV by 78.5%, wind energy shares 11.3% of load demand, and 10.2% from battery banks. The developed analysis concludes that the objective function is feasible for the selected locations. The study has three novelties. Firstly, the required load at different locations of the university’s buildings at KSA is supplied by minimizing COE. The objective function is achieved by considering a combination of HRES. Then, it applies the sensitivity analysis for several cases such as payback time, gird’s tariff variation, and load demand change. Finally, the current analyses are applicable to any university at KSA and around the world.

The trend is now to use renewable energy sources to improve energy efficiency in the building sector and preserve the environment. The use of sources as renewable off-grid applications for driven applications in home sector (micro-grids) is very interesting nowadays. The economic factor and the cost of establishing these grids is the main obstacle to these investments. One of the key solutions to reduce the cost and increase the reliability of these grids is how to optimally determine the ratings and combination of some renewable sources based on the location of the house. This paper presents an effective techno-economical design of a stand-alone hybrid system. The system contains a photovoltaic (PV), wind turbine, battery, and diesel generator. This design is performed through an extensive examination of the techno-economical design of a standalone system to provide the desired energy load for a typical household building for both Albaha and Buraydah cities in Saudi Arabia. These two cities have different geographical locations as Albaha is located at latitude 20.0217 degrees north while Buraydah is located at 26.3592 degrees north. These two cities were selected due to the difference in their geographical locations to study the effect of the weather on the building performance in terms of cost of energy, energy penetration, and load met. To enhance the performance of the proposed hybrid system, some constraints were selected, such as Net Present Cost (NPC), and Total Annual Cost (TAC). Results demonstrate that stand-alone hybrid renewable energy systems can be applied to improve energy efficiency and economics of the existing buildings. Integration of PV system, wind turbine, battery, and diesel generator in the best configuration can provide a minimum cost of energy of about $0.596/kWh and $0.603/kWh for Albaha and Buraydah cities, respectively.

SUMMARY This paper presents an optimum sizing methodology to optimize the hybrid energy system (HES) configuration based on genetic algorithm. The proposed optimization model has been applied to evaluate the techno-economic prospective of the HES to meet the load demand of a remote village in the northern part of Saudi Arabia. The optimum configuration is not achieved only by selecting the combination with the lowest cost but also by finding a suitable renewable energy fraction that satisfies load demand requirements with zero rejected loads. Moreover, the economic, technical and environmental characteristics of nine different HES configurations were investigated and weighed against their performance. The simulation results indicated that the optimum wind turbine (WT) selection is not affected only by the WT speed parameters or by the WT rated power but also by the desired renewable energy fraction. It was found that the rated speed of the WT has a significant effect on optimum WT selection, whereas the WT rated power has no consistent effect on optimal WT selection. Moreover, the results clearly indicated that the HES consisting of photovoltaics (PV), WT, battery bank (Batt) and diesel generator (DG) has superiority over all the nine systems studied here in terms of economical and environmental performance. The PV/Batt/DG hybrid system is only feasible when wind resource is very limited and solar energy density is high. On the other hand, the WT/Batt/DG hybrid system is only feasible at high wind speed and low solar energy density. It was also found that the inclusion of batteries reduced the required DG and hence reduced fuel consumption and operating and maintenance cost. Copyright © 2014 John Wiley & Sons, Ltd.

The reliance on fossil fuels for electricity generation drives carbon emissions and climate change. This study evaluates the technical and economic feasibility of a hybrid photovoltaic (PV)/wind turbine (WT)/diesel generator (DG) system in the north-central Mudug region of Somalia. Using MATLAB simulations, ten system configurations were analysed, including standalone DG, hybrid PV/DG, WT/DG, and PV/WT/DG, with and without battery storage (BS). Key metrics assessed include net present cost, levelized cost of energy, renewable fraction, excess electricity, and CO₂ reduction. The optimal configuration (Case 8) consists of a 50 kW DG, 80 kW PV, 90 kW WT, and 14 BS units, achieving a 71.5% renewable fraction, a net present cost of $701,083, and an energy cost of $0.2/kWh. This system reduces net present cost by 51% and fuel costs by 19% compared to DG alone. The findings highlight the economic and environmental viability of hybrid renewable systems in Mudug.

Optimal design and economic analysis of a hybrid renewable energy system for powering and desalinating seawater

Technical and economic effects of charge controller operation and coulombic efficiency on stand-alone hybrid power systems

This paper presents the feasibility study and optimal design of different stand-alone and grid-connected renewable energy systems (RES) to supply power for a dairy factory in Tehran, Iran. To achieve an optimal system, different technical, economical, and environmental factors including net present cost (NPC), cost of energy (COE), renewable fraction (RF), and greenhouse gases emission (GHGE) are considered in the design process. An optimal system is a system that supplies the load with specified constraints, while having the least NPC, COE, and GHGE. Modeling, simulation, and analysis of power supply systems are implemented in Hybrid Optimization Model for Electric Renewables (HOMER). Due to the current low price of energy and subsidies in Iran, the best choice for the energy supply is the utilization of the external grid. Despite the laws related to the exchange of RES-produced electricity in Iran, no laws are legislated to deal with the environmental issues especially the GHGE. However, as the environmental protection laws are to be passed in the near future, we assumed typical values for the sellback rate and emission penalties and investigated the effect of these two parameters on NPC, COE, RF, and GHGE. In this paper, a systematic approach to select an optimal power supply system by effective utilization of dedicated optimization software like HOMER is presented. The simulations showed that when considering both the increase in the energy cost and suitable penalties for GHGE, the grid-connected RES was the optimum configuration for the energy supply. In general, if environmental protection laws take effect in developing countries, the grid-connected RES shows its great potential as an economic and pollution-free supply of energy.

Quantitative techno-economic comparison of a photovoltaic/wind hybrid power system with different energy storage technologies for electrification of three remote areas in Cameroon using Cuckoo search algorithm

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 CO2 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 CO2 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 CO2 emissions.

The role of energy storage systems in resilience enhancement of health care centers with critical loads

The objective of this paper is to investigate the potential of reducing the dependence on the consumed energy from the main grid using a Hybrid Renewable Energy System (HRES) at two university’s locations, namely; Al Baha University and University of Bahrain. The feasibility analysis of a HRES includes technical and economic features, which is examined for photovoltaic array (PV), wind turbine (WT), DC/AC converter, and battery banks at autonomous and grid-connected modes. The simulation results address that the developed system at University of Bahrain has the lowest Net Present Cost (NPC) and Cost of Energy (COE). It can be recognized from the simulation results that NPC of a developed Grid/PV system is more appropriate than other configurations, at the current tariff, which results a renewable fraction of more than 30% and 54.3% reduction in CO 2 . University of Bahrain has the optimized system of integration of 36 kW PV array with the main grid which leads to the minimum cost of energy (COE) of 0.0749 $/kWh. The study also provides an optimal configuration of HRES-only system to cover the full load demand (>99.9%) by a contribution from solar PV by 74.8%, wind energy shares 15% of load demand, and 10.2% from battery. The study addresses two major contributions. Firstly, the lowest COE determines the optimal configurations for fully supply the load at different locations of the university’s buildings. Then, it applies the feasibility and sensitivity analyses for several case studies such as payback time, tariff changes, and load demand variation.

This paper presents an analysis and optimization of an isolated hybrid renewable power system to operate in the Alrashda village in the Dakhla Oasis, which is situated in the New Valley Governorate in Egypt. The proposed hybrid system is designed to integrate a biomass system with a photovoltaic (PV), wind turbine (WT) and battery storage system (Bat). Four different cases are proposed and compared for analyzing and optimizing. The first case is a configuration of PV and WT with a biomass system and battery bank. The second case is the integration of PV with a biomass system and battery bank. The third case is WT integrated with biomass and a battery bank, and the fourth case is a conventional PV, WT, and battery bank as the main storage unit. The optimization is designed to reduce component oversizing and ensure the dependable control of power supplies with the objective function of reducing the levelized cost of energy and loss of power supply probability. Four optimization algorithms, namely Heap-based optimizer (HBO), Franklin’s and Coulomb’s algorithm (CFA), the Sooty Tern Optimization Algorithm (STOA), and Grey Wolf Optimizer (GWO) are utilized and compared with each other to ensure that all load demand is met at the lowest energy cost (COE) for the proposed hybrid system. The obtained results revealed that the HBO has achieved the best optimal solution for the suggested hybrid system for case one and two, with the minimum COE 0.121171 and 0.1311804 $/kWh, respectively, and with net present cost (NPC) of $3,559,143 and $3,853,160, respectively. Conversely, STOA has achieved the best optimal solution for case three and four, with a COE of 0.105673 and 0.332497 $/kWh, and an NPC of $3,103,938 and $9,766,441, respectively.

In this paper, a new application of Equilibrium Optimizer (EO) is proposed for design hybrid microgrid to feed the electricity to Dakhla, Morocco, as an isolated area. EO is selected to design the microgrid system due to its high effectiveness in determining the optimal solution in very short time. EO is presented for selecting the optimal system design which can minimize the cost, improve the system stability, and cover the load at different climate conditions. Microgrid system consists of photovoltaic (PV), wind turbine (WT), battery, and diesel generator. The objective function treated in this paper is to minimize the net present cost (NPC), respecting several constraints such as the reliability, availability, and renewable fraction. The sensitivity analysis is conducted in two stages: Firstly, the impact of wind speed, solar radiation, interest rate, and diesel fuel on the NPC, and levelized cost of energy (LCOE) is analyzed. Secondly, the influence of size variation on loss of power supply probability (LPSP) is investigated. The results obtained by EO are compared with those obtained by recent metaheuristics optimization algorithms, namely, Harris Hawks Optimizer (HHO), Artificial Electric Field Algorithm (AEFA), Grey Wolf Optimizer (GWO), and Sooty Tern Optimization Algorithm (STOA). The results show that the optimal system design is achieved by the proposed EO, where renewable energy sources (PV and WT) represent 97% of the annual contribution and fast convergence characteristics are obtained by EO. The best NPC, LCOE, and LPSP are obtained via EO achieving 74327 $, 0.0917 $/kWh, and 0.0489, respectively.