A fuzzy decision-making model for optimal design of solar, wind, diesel-based RO desalination integrating flow-battery and pumped-hydro storage: Case study in Baltim, Egypt

With the continuous development of distributed solar, wind power and other renewable energy sources, renewable energy sources which has its own features, such as intermittent and randomness volatility, brings great challenges to the stable operation of power grid. Aiming at meeting the requirement of balancing the fluctuating renewable energy sources of micro grid, this paper proposes the operating control strategies of the zinc bromine flow battery storage. Firstly, the equivalent mathematical model based on the working principle of the zinc bromine flow battery is established; Secondly, a dual closed-loop strategy for the DC/DC converter is proposed, of which the inner loop is peak current control on zinc bromine flow battery side inductance while the outer loop is a switch control by constant active power and trickle current. By resorting the DC/AC grid side converter, the stability of DC bus voltage is maintained; Then, this paper proposes the optimization power control strategies of zinc bromine battery energy storage system as a constraint of state of charge and DC bus voltage; Finally, a 50kW zinc bromine flow battery energy storage system test platform is built, and the charging and discharging characteristics of zinc bromine energy storage system (ZESS) is researched in grid-connected mode, the test results have shown that the proposed power optimization control strategies for zinc bromine energy storage system could smooth renewable energy sources power fluctuation.

The use of zinc-bromine flow battery technologies has a number of advantages for large-scale electrical energy storage applications including low cost,long service life and environmental friendliness.It has a huge potential for a high extent of renewable energy penetration,distributed generation and smart grid.This paper briefly introduces the principle and component configuration of zinc-bromine flow batteries,analyzes their characteristics,and reviews recent state-of-art development in the area.Finally,recommendations for future research are proposed.

This paper presents an exploration of the potential of hybrid renewable energy systems (HRESs), combining floating solar photovoltaics (FPV), wind turbines, and vanadium redox flow (VRF) battery energy storage systems (BESSs) to expedite the transition from conventional to renewable energy for the mining sector in South Africa. The feasibility study assesses how to enhance the overall efficiency and minimize greenhouse gas emissions from an economic standpoint by using the Hybrid Optimization of Multiple Energy Resources (HOMER) grid software version 1.11.1 and PVsyst version 7.4. Furthermore, the BESS Covariance Matrix Adaptation Evolution Strategy (CMA-ES) dispatch algorithm is proposed to make the most of the battery storage capacity and capability, aligning it with the dynamic energy demand and supply patterns of an HRES. The proposed HRES includes a highly efficient SFPV with a performance ratio of 0.855 and an annual energy production of 15,835 MWh; a wind turbine (WT) operating for 2977 h annually, achieving a 25% wind penetration rate; and a dynamic VRF-BESS with a 15,439 kWh life throughput and a 3 s dispatch response time. This HRES has a CapEx of R172 million, a 23.5% Internal Rate of Return (IRR), and an investment payback period of 4.9 years. It offers a low Levelized Cost of Energy (LCoE) at 4.27 R/kWh, a competitive Blended Cost of Energy (BCoE) at 1.91 R/kWh, and a positive net present cost (NPC), making it economically advantageous without external subsidies. Moreover, it annually reduces CO2 emissions by 1,715,468 kg, SO2 emissions by 7437 kg, and NOx emissions by 3637 kg, contributing to a significant environmental benefit.

This paper analyses the performance of a hybrid renewable energy system (HRES) by comparing it to a standalone diesel generator when both are used independently to power a Base Transceiver Station (BTS) at Sigonde village in Limpopo, South Africa. The comparison is based on energy output, economics and emission of pollutants. The hybrid optimization of multiple energy resources (HOMER) software was used to simulate and optimize both systems. The objective is to develop a cost-effective HRES that performs better than standalone diesel generator and emits less to zero pollutants. This hybrid power supply system comprises of solar, wind and fuel-cell power sources with a battery back-up pack. Furthermore, the system has zero capacity shortage, zero unmet load and abides by the country's discount rate of 6.75%. The results showed that the best system to power the BTS at Sigonde village is made up of 12.25 kW solar PV capacity, 1 kW wind turbine, 4 kW fuel-cell, 10.5 kWh capacity battery and a 3.75 kW converter. The HRES costs 50% (Net Present Cost and Cost of Energy), emits 80% less pollutions and lastly, has an excess energy of 10079 kWh.

This paper presents a concept design of a hybrid renewable energy system (HRES). The proposed HRES design specifies the operation of the following units: a pumped-storage hydro power plant, a wind power plant and a solar power plant. Since the pumped-storage hydro power plant represents the most complex entity of the HRES, special emphasis is placed on its two control loops: the water tank level control loop and the load-depended frequency control loop. Models of these control loops provide the means for efficient controller design and implementation. In order to achieve effective energy distribution and reliable power supply of the consumers, a switch logic architecture has been developed. Since the HRES's final energy production highly depends on the process of energy conversion, the performances of three types of power converters are analysed. This includes the parametrisation, modelling and simulation of such converters. Finally, a graphical user interface (GUI) for purposes of data monitoring, control and supervision within the designed SCADA system, is presented. The proposed HRES design represents the foundation of the system implementation that aims at serving as a platform for research, education and a broad range of projects on renewable energy.

The aim of this study is to evaluate the technical performance and resilience of a Hybrid Renewable Energy System (HRES), designed to achieve water and energy autonomy on a Skyros Island, Greece. The system integrates renewable energy sources with multiple storage technologies. A high-resolution, 30-min simulation was developed, incorporating 10 years of historical weather data to model the operation of an HRES, which consists of wind turbines, photovoltaics, pumped hydro storage, and green hydrogen production. Reverse osmosis was used for desalination, and extended low-wind conditions were simulated to assess system resilience. Results indicate that the proposed system is, in fact, capable of meeting 89% of the annual energy demand and 99.99% of freshwater requirements by means of desalination. Wind power accounted for 53% of the total energy production, photovoltaics 2%, while pumped hydro and hydrogen storage contributed 17% and 6%, respectively. During artificially imposed windless periods, short-term deficits were addressed by the use of pumped hydro, while hydrogen ensured supply continuity in the final days, thereby demonstrating their complementary function. In this resilience stress-test, the system remained operational for 10 days during an artificial windless period, demonstrating the critical role of hybrid storage. The findings indicate that a combination of renewable energy with diversified storage and water management strategies can provide a reliable and self-sufficient water–energy nexus for remote islands. Finally, the novelty of this research work lies in the statistical analysis of calm-wind events and the development of the corresponding power-law relationship, conducted under the framework of the 30-min simulation.

In 2019–2020, with encouragement from the Government in promoting the development of renewable energy sources, Vietnam has witnessed the rapid growth of solar and wind power sources. By the end of 2020, there were 16,700MW of solar power capacity connected to the national grid and accounted for 24 percent of the capacity of the whole national grid. These renewable energy sources are mainly concentrated in the Ninh Thuan and Binh Thuan provinces of Vietnam. The transmission power grid has not developed in time in this area to relieve all power sources, so there has been an overcapacity situation that has led to a reduction in the generating capacity of power plants, causing a waste of resources. In this paper we introduce renewable energy source storage technology based on pumped-storage hydroelectricity (PSH) technology, evaluating the role of a PSH plant in balancing the capacity of the power system when the system is connected to unstable power sources such as solar and wind power. Also, in this research, we propose Model Predictive Controller (MPC) built through LabView software to control the power balance on the grid. The results of the research show that the solution to building a PHS plant to optimize renewable energy sources in the central provinces of Vietnam is the right solution for Geographically favorable conditions, PHS also brings economic profit and stabilizes Vietnam's electricity system

This paper presents the power grid system analysis with solar power sources, wind turbine resources, and energy storage system integration by using the Open Distribution System Simulator (OpenDSS) program. According to the energy storage systems (ESS), improve grid reliability, flexibility, and energy quality issues of renewable energy sources. This study analyzes the power grid system and its continuity when the solar power sources and wind turbine resources have worked with energy storage systems. The OpenDSS is selected to represent the performance of the proposed study in this article. The simulation results found that the integration of photovoltaic, Wind Turbine Power energy, and energy storage systems can decrease the minimum power consumption and power loss.

Energy, economic and environmental (3E) evaluation of a hybrid wind/biodiesel generator/tidal energy system using different energy storage devices for sustainable power supply to an Indian archipelago

The non-interconnected islands of Greece can benefit from the comprehensive use of RES to avoid water droughts and ensure energy autonomy. The present paper analyzes an HRES with two possible operating scenarios. Both of them include a wind park of 27.5 MW capacity, an 1175 m3/day desalination plant, and a 490,000 m3/day water tank in Lemnos, Greece. Regarding the wind power, 70% is used in the HRES, while the rest is channeled directly to the grid. The main difference comes down to how the wind energy is stored, either in the form of hydraulic energy or in the form of hydrogen. The lifespan of the system is 25 years, such as the produced stochastic series of rainfall, temperature, and wind of the area. Through the comparison of the operating scenarios, the following results arise: (i) the water needs of the island are fully covered and the irrigation needs have a reliability of 66%, in both scenarios. (ii) Considering the energy needs, the pumping storage seems to be the most reliable solution. (iii) However, depending on the amount of wind energy surplus, the use of hydrogen could produce more energy than the hydroelectric plant.

Battery storage technologies such as redox flow batteries (RFBs) and lithium-ion batteries (LIBs) are appealing candidates for large-scale energy storage requirements to support the integration of renewable energy into electric grids. To ensure that their environmental benefits outweigh the environmental costs of producing battery storage systems, it is vital to assess the potential health impacts of battery materials and waste emissions during production. Here, we present a case study based on life cycle impact assessment (LCIA) to characterize the toxicity hazard associated with the production of six types of battery storage technologies including three RFBs [vanadium redox flow battery (VRFB), zinc-bromine flow battery (ZBFB), and the all-iron flow battery (IFB)], and three LIBs [lithium iron phosphate (LFP), lithium nickel cobalt manganese hydroxide (NCM), and lithium manganese oxide (LMO)]. USETox® v2.0 (USETox®) was used for LCIA and we found higher impacts found higher impacts on human health outcomes for the production of LIBs than for RFBs, noting that uncertainties associated with the characterization factors demand caution in interpreting the results. Overall, the study provides (1) a comprehensive evaluation of life cycle impacts for materials, components, and systems associated with the production of burgeoning six battery energy storage technologies and (2) an important foundation for the identification of battery technologies with lower potential negative impacts associated with integrating energy storage in strategies for upscaling renewable energy sources.KeywordsBatteryEnergy storageEnergy gridRenewableLife cycle impact assessmentHuman health impact

The paper presents an optimization technique for scheduling of pumped-storage power plant operation up to one year horizon. A pumped-storage power plant is an energy source with fast time response consisting of upper and lower reservoir, which has ability to store excess electric energy in the upper reservoir in form of potential energy of water, which is pumped from the lower reservoir. Its importance increases as a tool for transmission system operator to control of power system stability, load balancing and frequency control due to the increase of amount of power generated from renewable energy sources characterized by the fluctuation of power output such as photovoltaic and wind power sources. Usually, it has part of capacity reserved for needs of transmission system operator and the remaining capacity can be used by the plant operator in commercial manner to increase of profit. The aim of the paper is to propose fast algorithm based on dynamic programming to optimize free capacity while complying with all the technical and operational restrictions.

The usage of renewable energy to generate electricity is growing day by day and solar and wind energy is seen as the most viable electrification options. In comparison to a single renewable source, hybrid electric systems have recently gained a lot of attention due to their various advantages. Different types of energy generating systems such as generators, electrical energy storage systems, and renewable energy sources are combined in hybrid systems. This technology appears to be the most viable option for off-grid power generation. Battery energy storage is required for this hybrid system in order to store excess energy generated by renewable resources and provide it during times of scarcity. Many battery technologies are developing these days with superior features to traditional batteries, which may be compared in terms of reaction time, deep cycle discharge, efficiency, lifetime, and so on. The goal of this study is to use HOMER Pro software to build and model a Hybrid Energy System (HES) that includes Photovoltaic (PV), wind energy, and a diesel generator. Secondly, several battery types such as Lead Acid (LA) battery, Lithium Ion (LI) battery, Li-ion Nickel-Manganese-Cobalt Oxide battery (LiNiMnCoO2), Zinc Bromine Flow Battery, and Nickel Iron Battery are used to design HES. Finally, the Hybrid Renewable Energy System (HRES) is compared in terms of system size, economy, technical performance, and environmental stability utilizing various battery technologies.

Hybrid renewable energy systems, complemented by pumped hydropower storage, have become increasingly popular amidst the increase in renewable energy penetration. Such configurations are even more prosperous in remote regions that are typically not connected to the mainland power grid, where the energy independence challenge intensifies. This research focuses on the design of such systems from the perspective of establishing an optimal mix of renewable sources that takes advantage of their complementarities and synergies, combined with the versatility of pumped hydropower storage. However, this design is subject to substantial complexities, due to the multiple objectives and constraints to fulfill, on the one hand, and the inherent uncertainties, on the other, which span over all the underlying processes, i.e., external and internal. In this vein, we utilize a proposed hybrid renewable energy system layout for the Aegean Island of Sifnos, Greece, to develop and evaluate a comprehensive simulation-optimization scheme in deterministic and, eventually, stochastic settings, revealing the design problem under the umbrella of uncertainty. In particular, we account for three major uncertain elements, namely, wind velocity (natural process), energy demand (anthropogenic process), and wind-to-power conversion (internal process, expressed in terms of a probabilistic power curve). Emphasis is also given to the decision-making procedure regarding the system’s key design parameters (reservoir size and solar power capacity), which is achieved by thoroughly interpreting the uncertainty-aware optimization outcomes. Finally, since the proposed pumped hydropower storage uses the sea as the lower reservoir, additional technical challenges are addressed.

Deeply research vanadium redox flow battery (VRB) energy storage technology in the field of power system, it should establish battery system simulating model to study the system operating characteristics. Electrochemical battery, however, belongs to non-linear time-varying system, and the internal chemical material properties are susceptible to variety of factors. Battery model should not be simply equivalent to an ideal voltage source or current source. The target model should reflect most characteristics of battery, such as the internal resistance, polarization, self-discharge, shunt current loss and temperature or even other factors which may influence the operating characteristics of the battery system. First it defined the key parameters of VRB characteristics from the point of application, then based on the external characteristics of VRB system, the system-level quasi-steady-state model had been established, which contains the factor time-varying, temperature change and shunt current etc. Then by simulating on the platform of PSCAD/EMTDC, the model proved to be correct and well reflected the charge and discharge characteristics and dynamic response characteristics of VRB system.