Modeling and simulation of an isolated hybrid micro-grid with hydrogen production and storage

Abstract This work relates the study of system performance in operational conditions for an isolated micro-grid powered by a photovoltaic system and a wind turbine. The electricity produced and not used by the user will be accumulated in two different storage systems: a battery bank and a hydrogen storage system composed of two PEM electrolyzers, four pressurized tanks and a PEM fuel cell. One of the main problems to be solved in the development of isolated micro-grids is the management of the various devices and energy flows to optimize their functioning, in particular in relation to the load profile and power produced by renewable energy systems depending on weather conditions. For this reason, through the development and implementation of a specific simulation program, three different energy management systems were studied to evaluate the best strategy for effectively satisfying user requirements and optimizing overall system efficiency

Optimal operation of hybrid AC/DC microgrids under uncertainty of renewable energy resources : A comprehensive review

The hybrid AC/DC microgrids have become considerably popular as they are reliable, accessible and robust. They are utilized for solving environmental, economic, operational and power-related political issues. Having this increased necessity taken into consideration, this paper performs a comprehensive review of the fundamentals of hybrid AC/DC microgrids and describes their components. Mathematical models and valid comparisons among different renewable energy sources’ generations are discussed. Subsequently, various operational zones, control and optimization methods, power flow calculations in the presence of uncertainties related to renewable energy resources are reviewed.fi=vertaisarvioitu|en=peerReviewed

Use of Micro-Cogeneration in Microgrids to Support Renewables

The use of renewable energy sources has experienced great development so as to meet energy demand. With the intention of increasing the utilization of the renewable energy sources near the demand side and compensate the fluctuation of the output power, the use of micro-cogeneration systems with solar (PV) and wind energy overcomes both technical and economic barriers. Micro-cogeneration-based hybrid PV/wind energy system can get stable power output. This new energy model also improves the power quality and significantly reduces the impact of power instability on the power network. In this study, the grid-connected hybrid PV/wind energy-based micro-cogeneration system is modeled and analyzed in detail. In order to test the performance analysis of the system, seven different scenarios are analyzed during the case studies. The analysis results show that the new energy model presents effective solutions to electrical power balance because of its properties such as safety, incombustible structure, and being eco-friendly. It is aimed at providing a broad perspective on the status of optimum design and analysis for the micro-cogeneration-based hybrid PV/wind energy system to the researchers and the application engineers dealing with these issues

Challenges and prospects of renewable hydrogen-based strategies for full decarbonization of stationary power applications

The exponentially growing contribution of renewable energy sources in the electricity mix requires large systems for energy storage to tackle resources intermittency. In this context, the technologies for hydrogen production offer a clean and versatile alternative to boost renewables penetration and energy security. Hydrogen production as a strategy for the decarbonization of the energy sources mix has been investigated since the beginning of the 1990s. The stationary sector, i.e. all parts of the economy excluding the transportation sector, accounts for almost three-quarters of greenhouse gases (GHG) emissions (mass of CO2-eq) in the world associated with power generation. While several publications focus on the hybridization of renewables with traditional energy storage systems or in different pathways of hydrogen use (mainly power-to-gas), this study provides an insightful analysis of the state of art and evolution of renewable hydrogen-based systems (RHS) to power the stationary sector. The analysis started with a thorough review of RHS deployments for power-to-power stationary applications, such as in power generation, industry, residence, commercial building, and critical infrastructure. Then, a detailed evaluation of relevant techno-economic parameters such as levelized cost of energy (LCOE), hydrogen roundtrip efficiency (HRE), loss of power supply probability (LPSP), self-sufficiency ratio (SSR), or renewable fraction (fRES) is provided. Subsequently, lab-scale plants and pilot projects together with current market trends and commercial uptake of RHS and fuel cell systems are examined. Finally, the future techno-economic barriers and challenges for short and medium-term deployment of RHS are identified and discussed.This research is being supported by the Project ENERGY PUSH SOE3/P3/E0865, which is co-financed by the European Regional Development Fund (ERPF) in the framework of the INTERREG SUDOE Programme and the Spanish Ministry of Science, Innovation, and Universities (Project: RTI2018-093310-B-I00)

Modelling and Control of a Grid-Connected RES-Hydrogen Hybrid Microgrid

This paper proposes a Hybrid Microgrid (HµG) model including distributed generation (DG) and a hydrogen-based storage system, controlled through a tailored control strategy. The HµG is composed of three DG units, two of them supplied by solar and wind sources, and the latter one based on the exploitation of the Proton Exchange Membrane (PEM) technology. Furthermore, the system includes an alkaline electrolyser, which is used as a responsive load to balance the excess of Variable Renewable Energy Sources (VRES) production, and to produce the hydrogen that will be stored into the hydrogen tank and that will be used to supply the fuel cell in case of lack of generation. The main objectives of this work are to present a validated dynamic model for every component of the HµG and to provide a strategy to reduce as much as possible the power absorption from the grid by exploiting the VRES production. The alkaline electrolyser and PEM fuel cell models are validated through real measurements. The State of Charge (SoC) of the hydrogen tank is adjusted through an adaptive scheme. Furthermore, the designed supervisor power control allows reducing the power exchange and improving the system stability. Finally, a case, considering a summer load profile measured in an electrical substation of Politecnico di Torino, is presented. The results demonstrates the advantages of a hydrogen-based micro-grid, where the hydrogen is used as medium to store the energy produced by photovoltaic and wind systems, with the aim to improve the self-sufficiency of the system

Techno-Economic Analysis of Hybrid Renewable Energy Systems for Electrification of Rustic Area in Egypt

Hybrid Power Systems (HPSs), particularly renewable energy-mix systems, use a wide variety of enabling technologies to overcome the difficulties associated with Renewable Energy (RE) resource variability in both standalone and grid-connected systems. According to the Egyptian national program towards reaching the 2020 objectives together with the continuous declination of the RE generation cost, extensive development and deployment of RE are witnessed from the government, academia, utilities and industry in Egypt. Therefore, this paper mainly aims at highlighting the potential of RE-hydrogen concept application for rural electrification in the small villages in Egypt in comparison with batteries. After introducing the comprehensive literature review that demonstrates the advantages and drawbacks of the RE standalone systems that mostly necessitates an Energy Storage System (ESS) support. The optimal.conomic design of the HPS that feeds the required electric load of the small Mansheat Taher village at Beni-Suef Governorate, Egypt is considered. For this purpose, five different HPS configurations are studied such as: PV-wind-battery, PV-Fuel Cell (FC), wind-FC, PV-wind-FC, and PV-wind-battery-FC systems. The models of various systems are optimally designed, sized based on the daily data for energy availability and the demand using HOMERTM software. From the viability analysis of the simulation results, HPS system of xxxxxxx that provides a total net present cost of $1,233,317 is considered the most economic and feasible option. The cost of energy is 0.1424$/kwh with a required initial capital of $916,728. A case study area, Monshaet Taher village at Beni-Suef Governorate, Egypt with (29° 1' 17.0718"N, 30° 52' 17.04"E) is identified for economic feasibility in this work. HOMER optimization model plan was designed with annual average solar radiation scaled of 5.93 (kWh/m2/day), annual average wind speed for the location is 4.92 m/s. Keywords: Batteries, Energy Storage; Fuel Cells; Hybrid System; Renewable Energy; Rural Electrification

Fuzzy logic control of hybrid systems including renewable energy in microgrids

With a growing demand for more energy from subscribers, a traditional electric grid is unable to meet new challenges, in the remote areas remains the extension of the conventional electric network very hard to do make prohibitively expensive. Therefore, a new advanced generation of traditional electrical is inevitable and indispensable to move toward an efficient, economical, green, clean and self-correcting power system. The most well-known term used to define this next generation power system is Micro Grid (MG) based on renewable energy sources (RES). Since, the energy produced by RES are not constant at all times, a wide range of energy control techniques must be involved to provide a reliable power to consumers. To solve this problem in this paper we present a Fuzzy Logic Control of isolated Hybrid Systems (HRES) Including Renewable Energy in Micro-Grids to maintain a stability in voltage and frequency output especially in the standalone application. The considered HRES combine a wind turbine (WT) and photovoltaic (PV) panels as primary energy sources and an energy storage system (ESS) based on battery as a backup solution. Simulation results obtained from MATLAB/Simulink environment demonstrate the effectiveness of the proposed algorithm in decreasing the electricity bill of customer

A review of energy management strategies for renewable hybrid energy systems with hydrogen backup

Hybrid systems are presented as a viable, safe and effective solution to minimize the associated problems of the dependence on renewable energies with the environmental resources. In this way different renewable systems such as photovoltaic, wind, hydrogen and so on, can work together to configure hybrid renewable systems. However, to make them work properly in a holistic way by creating synergies among them is not an easy task. Recently hydrogen technology has appeared as a promising technology to hybridize renewable energy systems, since it allows the generation (by electrolyzers) and storage of hydrogen when there is a surplus of energy in the system, and at a later time (e.g. when there are insufficient renewable resources available) using the stored hydrogen to generate electrical energy by fuel cells. The choice of a correct energy management strategy should guarantee an optimum performance of the whole hybrid renewable system; therefore, it is necessary to know the most important criteria in order to define a management strategy that ensures the best solution from a technical and economic point of view. This paper presents a critical review and analysis of different energy management strategies for hybrid renewable systems based on hydrogen backup. In the same way, a review is also presented of the most important technical and economic optimization criteria, as well as problems and solutions studied in the scientific literature