Stand-alone Hybrid Power System Research Articles

Standalone hybrid power system using homer software optimal case sizing of ferraguig (North West of Algeria)

Rural areas suffer from high costs of grid extensions obliging institutions to provide for other remedies for consumers, like using generators (GE) diesel often considered as economic and reliable solutions, but at the detriment of some order environment pollution and users convenience. Furthermore, the continuous decline in GEs prices based on a renewable energy (RE) and the increasing reliability of these systems have lead to a greater use of renewable energy sources for power generation in remote areas. A property which limits the use of renewable energy is related to the variability of resources. Fluctuations in load according to annual or daily periods are not necessarily correlated to the resources. In remote areas, the preferred option is the coupling between multiple sources, such as wind turbines and solar panels, this coupling is called hybrid power system. Algeria’s geographic location presents several advantages for the development and use of renewable energy, namely, solar energy and wind energy. In addition, Algeria has huge deposits of natural gas, 98% electricity comes from gas. Therefore, currently, the production of electricity from renewable energies primarily depends on their competitiveness with economic gas. Studied technological feasibility and economic viability of the hybrid system (PV/fuel) electrification project in a school located in Ferraguig succeed to reduce high costs, energy dependence, fuel supply problem, complicated/expensive maintenance, low lifetime, impossibility of 24 hours electricity production and waste oil management issues, by using renewable energy. HOMER model is used here to size a proposed system and determine an optimum configuration.

Solar-hydrogen renewable supply system optimisation based on demand side management

Stand-alone hybrid power systems are an alternative to main electricity grids, where the grid extension is costly or the trifling local consumption would not justify its expansion. However, lack of consistency and uniformity in renewable energy sources, and the restrictions of energy storage systems make system sizing a challenging task. Optimum size of a stand-alone system depends on several factors including energy demand function. In this paper, different types of demand functions are addressed for optimising a solar-hydrogen supply system. Different parameters are defined to investigate the impact of household population on the power generation cost, and also to determine the optimum supply system specifications. Eventually, using an economic analysis on the desired system, the capitation costs of the electricity generated by this system are compared for different household demand functions. Outcomes suggest that electricity decreases in the demand functions with higher averages and uniform load distribution.

PV-Wind-Battery Hybrid Power Systems: Power Management Control Strategy Using P2D Battery Model

A standalone hybrid power system (SHPS) using renewable energy resources (RERs) like wind, solar, hydro and biomass can be installed at any remote location where power grid extension is either not possible or too expensive. However, these RERs have drawbacks like unpredictable nature, intermittency, dependence on location and mismatch of generated power with load demand. To overcome the above limitations SHPSs are often integrated with battery energy storage system (BESS) [1]. Lithium-ion batteries (LiBs) are one of the most popular and emerging options for energy storage for SHPSs [2]. The financial feasibility of the SHPSs depends on the operation and performance of LiBs which is one of the most expensive components. Improperly designed BESS leads to a high life cycle cost or failure of the system to provide a reliable power supply and hence the power management and control in the SHPS is an active area of research. It is essential to manage the power flow between the load, the power generated by RERs and the battery to ensure the power stability in the system and guarantee continuous power supply to the end user [3]. Till now various researchers successfully implemented empirical/equivalent circuit models (ECM), which are less reliable under dynamic operating conditions, to design battery management systems and control algorithms due to the ease of their implementation in the control and operation of SHPSs [4, 5]. We present the use of physics-based battery (pseudo-2D) models representing the transport and kinetic processes that take place in the LiBs [6] which provides better control and prediction of battery performance to design robust power management control strategy for the SHPS consisting of PV-wind based generators integrated with Li-ion battery. The wind velocity is negatively correlated to solar insolation [7] and therefore we consider the solar-wind combination to utilize their complementary nature. This framework comprises of PV panels, wind turbines, Maximum Power Point Tracking (MPPT) controller, power electronics, and LiBs. A single-diode equivalent circuit-based model is used to model a solar cell. A differential algebraic equation based MPPT algorithm is implemented to track the maximum power point of the solar array [8]. The power output from the wind turbine generator is predicted using wind speed and speed characteristics of the turbine. The power management strategy guarantees 0% excess output power production, and ensuring no energy is transferred to the dump load. A case study will be presented for a year-long real-world data which would consider the seasonal variability in load demand and power generation. The load demand and power generated (by RERs) and power supplied by the battery for a sample 7-day data is shown in Figure 1. These models are used to study the effects of RERs and load demand uncertainties and variations in the operating conditions of hybrid systems. Further, we explore the possibilities of using a physics-based battery model for a Li-ion battery in designing optimal BESS capacity that minimizes capacity fade and thermal degradation.

A comprehensive methodology for setting up rural electrifications with minimum budgets on indigenous villages in Malaysia

PurposeThis paper aims to propose a comprehensive methodology for setting up rural electrifications for indigenous villages with minimum budgets and the lowest possible cost of electricity (COE). The electricity accessibility of rural area in Malaysia is not fully covered and the cost of extending the grid to these areas can be high as RM 2.7m per km. Lack of vigorous policies and economic attraction of the rural areas are also the main barriers to rural electrification. Electricity is an essential element of economic activities and the lack of electricity exacerbates poverty and contributes to its perpetuation. Therefore, a hybrid standalone power system can be an alternative solution for the rural electrification. A hybrid standalone power system is studied to investigate the potential of the implementation and the budget required.Design/methodology/approachA site survey has been carried out in a village in Peninsular Malaysia, namely, Kampung Ulu Lawin Selatan. A standalone hybrid system is modeled in HOMER Pro software and the data collected from the selected site are used to obtain the system configuration with the lowest COE. The load following and cycle charging energy dispatch methods are compared to identify the optimal system configuration that yields the lowest COE. The diesel generator-only system is chosen as a benchmark for comparisons.FindingsThe results show that the hybrid system constituted from the diesel generator, photovoltaic (PV), micro-hydro and energy storage using the load following energy dispatch method yields the lowest COE of RM 0.519 per kWh. The COE of the hybrid system is 378 per cent lower than that of the diesel generator-only system. The lead-acid energy storage system (ESS) is able to reduce 40 per cent of COE as compared to the system without ESS.Originality/valueThe results indicate that the COE of the diesel-micro hydro-PV-ESS system with load following dispatch strategy is RM 0.519 per kWh, and this value is 35 per cent higher than the average electricity price in Malaysia. However, it is important to note that the costs of extending the grid to the rural area are not taken into account. If this cost is considered into the electricity price, then the standalone hybrid power system proposed by this study is still a competitive alternative for rural electrification.

Linear matrix inequality approach in stability improvement through reactive power control in hybrid distributed generation system

Stability of a standalone hybrid power system (HPS) in a smart grid is always a challenging task. Further, the operational stability of the power system depends on the associated communication infrastructure. Therefore, it is always crucial to pick up a controller that can assure system's stability along with performance, despite disturbances like (load and input wind variations) with communication delays. Present study focuses on reactive power management and voltage stability issues of an isolated HPS. The stability aspects of HPS are improved through reactive power compensation, by custom power devices like static var compensator. The control aspects of SVC as well as the whole hybrid system are taken care by H ∞ linear matrix inequalities approach. Further, H-infinity control, Lyapunov stability along with linear matrix inequalities techniques estimate the delay boundary of controllers. The iterative performance of the proportional–integral–derivative controllers, and robust H ∞ damping controller of the HPS, are designed through LMI approach. Later experimental study of the HPS is done, with a prototype model in dSPACE real-time control environment. In this case, dSPACE 1104 is added for data acquisition and control. Adaptability and robustness of the proposed controllers are verified under fluctuating loads and uncertain wind power input.

An applied methodology for optimal sizing and placement of hybrid power source in remote area of South Algeria

This paper proposes an efficient approach based on Virus colony search (VCS) algorithm to optimize the sizing and placement of stand-alone hybrid power system including photovoltaic solar panels (PV) and battery bank in system which employ diesel generators (DGs) as pilot source of electrical energy formatting hybrid system. The optimization is carried out to incessantly satisfy the load demand. Two objectives have been defined: the reduction of the equalized cost system (economic objective) and equalized CO2 equivalent life cycle emissions (environmental objective). In the optimization problem, the dependability index of not supplied energy (NSE) is also considered to have a reliable system. The VCS algorithm is an effective and powerful approach that has fast convergence and high precision. This algorithm simulates diffusion and infection strategies for the host cells adopted by virus to survive and propagate in the cell environment. With the policies, the individual in the new algorithm explores and exploits the search space more professionally. This study is applied to Fort-Lotfi City: Tindouf (South of Algeria) that still needs access to National grid electricity due to economic and geography matters. The results prove the advantages of hybrid power systems in isolated locations ranging from being cost effective and reducing the accumulated emissions. The proposed algorithm is compared with PSO and MPSO algorithms which confirm its best performance and effectiveness.

Control of a stand-alone photovoltaic/battery bank system to supply energy to resistance load

<p><span lang="EN-US">In this paper, supervisor control for stand-alone hybrid power system to supply energy to resistance load is presented. The hybrid system is used to produce energy withoutinterruption and it consists of a photovoltaic generator (PV), and a battery bank. PV system work in parallel via DC/DC converter and the battery bank is used to store the excess of energy. The mathematical model topology, the identification of each subsystem and the control supervision of theglobal system are the contribution of this paper. Obtained results under Matlab/Simulink presented and discussed.</span></p>

Non-Smooth Bifurcation Analysis of Multi-Structure Multi-Operating-Mode Power Electronics Systems for Applications With Renewable Energy Sources

The stand-alone hybrid renewable power generation systems for local applications have gained popularity in recent years. However, due to the intermittent nature of the renewable resources, the hybrid renewable power generation systems are often designed to operate with multi-structure and multi-operating-mode. As a result, a non-smooth bifurcation may occur as the system switches its operating mode. This brief aims to study this kind of bifurcation. A formulation for multi-structure and multi-operating-mode system is described and a systematic procedure for analyzing the non-smooth bifurcation is given. A stand-alone photovoltaic-battery hybrid power system is taken as an example for illustrating the possible non-smooth bifurcation, which is further identified and analyzed with a discrete-time mapping model. Moreover, extensive circuit simulations and experiments verify the theoretical analysis.

Operation of Stand-Alone Microgrids Considering the Load Following of Biomass Power Plants and the Power Curtailment Control Optimization of Wind Turbines

Various stand-alone hybrid power systems are widely used to fulfil the electric loads for remote, rural villages. Although there are many investigations based on various aspects of renewable hybrids energy microgrids, the discussions about the application of biomass combustion power plants are rare. Also, detailed investigations of the system steady and transient stability analysis, and the power curtailment control optimization of wind turbines in these stand-alone hybrid systems are seldom found. This paper focuses on wind/biomass/diesel/battery stand-alone microgrids and discusses the system operation, energy management and dispatch issues detailed. The renewable and controllable biomass power is localized to follow the load fluctuations over a long timescale to decrease the power production from diesel and the peak-load shifting demands of the battery banks. An optimization strategy of the wind power curtailment control is also proposed to effectively decrease the frequency and amplitude of the pitch actor and, to some extent, improve the power generation through the combination of the active turbine speed control and pitch regulation. Then a parallel double-mode optimal operation strategy with a “fault detector” is presented to realize economic optimization dispatch under the normal mode and emergency power control for large disturbance scenarios. Finally, case studies of a microgrid on a remote Canadian aboriginal community are conducted to demonstrate the performance of the proposed methods.

Optimal design of stand-alone hybrid power system using wind and solar energy sources

Optimal design of stand-alone hybrid power system using wind and solar energy sources

Optimal design of stand-alone hybrid power system using wind and solar energy sources

Stand-alone hybrid renewable energy systems are more reliable than one-energy source systems. However, their design is crucial. For this reason, a new methodology with simulation having as aim to design an autonomous hybrid PV-wind-battery system is proposed. Based on a triple multi-objective, the present methodology combines life cycle cost (LCC), embodied energy (EE) and loss of power supply probability (LPSP). For a location, meteorological and load data have been collected and assessed. Afterwards, components of the system and optimisation objectives have been modelled. Finally, an optimal configuration has been put in place using a dynamic model and applying a controlled elitist genetic algorithm for multi-objective optimisation. This methodology has been applied successfully for the sizing of a PV-wind-battery system to supply at least 95% of yearly total electric demand of a residential house.

Interval type-2 fuzzy logic based determination of battery charging efficiency applied to standalone hybrid power system

Interval type-2 fuzzy logic based determination of battery charging efficiency applied to standalone hybrid power system

Prospects of hybrid photovoltaic–diesel standalone system for six different climate locations in Indian state of Tamil Nadu

In developing countries like India, very limited observatory stations are available to collect daily global solar radiation (GSR). This paper focuses to develop a common model for daily GSR estimation and standalone hybrid power system (HPS) design in view of six different climate locations in India. A new strategy is applied for finding the daily GSR model in Madurai location in Tamil Nadu, India. It is based on new parameter, which is named as 'approximate-bright sunshine duration' from the real-time measurement. The remaining six locations are estimated from the new model developed. In addition, to improve the accuracy of estimation, the developed linear one input variable model is further modified as two input variable model, based on the latitudes of six different climatic locations. The performances of developed one-input and two input models are analyzed using statistical indicators. The result shows that the developed two input variable model has provided excellent estimations for Madurai and also other six Indian climatic locations of latitudes ranging from 9°N to 13°N. This work also projects a detailed analysis of HPS design based on three meteorological data inputs to cover the residential energy demand. The NASA data, predicted ANFIS data (estimated data) and the measurement data are used in the analysis for the HPS feasibility and size optimization. The analysis shows that the hybrid configurations are same for all the locations, whereas PV and converter sizes are varied in the range of 47–52 kW and 23–27 kW, respectively.

Robust Power Management Control for Stand-Alone Hybrid Power Generation System

This paper presents a new robust fuzzy control of energy management strategy for the stand-alone hybrid power systems. It consists of two levels named centralized fuzzy supervisory control which generates the power references for each decentralized robust fuzzy control. Hybrid power systems comprises: a photovoltaic panel and wind turbine as renewable sources, a micro turbine generator and a battery storage system. The proposed control strategy is able to satisfy the load requirements based on a fuzzy supervisor controller and manage power flows between the different energy sources and the storage unit by respecting the state of charge and the variation of wind speed and irradiance. Centralized controller is designed based on If-Then fuzzy rules to manage and optimize the hybrid power system production by generating the reference power for photovoltaic panel and wind turbine. Decentralized controller is based on the Takagi-Sugeno fuzzy model and permits us to stabilize each photovoltaic panel and wind turbine in presence of disturbances and parametric uncertainties and to optimize the tracking reference which is given by the centralized controller level. The sufficient conditions stability are formulated in the format of linear matrix inequalities using the Lyapunov stability theory. The effectiveness of the proposed Strategy is finally demonstrated through a SAHPS (stand-alone hybrid power systems) to illustrate the effectiveness of the overall proposed method.

Optimum Design of a Stand-alone Hybrid Power System with Demand-side Management

Hybridising renewable energy sources improves the reliability of renewable energy systems for stand-alone applications. However, the high system cost is one of the setbacks that contribute to the slow growth of renewable energy development. The system cost can be reduced by optimal system design. This paper presents hybrid system design strategies that minimize the system capital cost. The design concept considers integration of demand-side management (DSM) strategy in the system design process. In this strategy, the residential load is divided into three categories and prioritized two of them. This reduces the peak load, in effect reduces the system design capacity. A traditional design method was used to design a hybrid system to meet a specific daily load profile of a typical 3-bedroom residential facility in Tema, Ghana. The system capacity, system capital cost, net present cost, capacity shortage and excess generation of the system were considered as hypothesis. The algorithm of the proposed design strategy was used to design an optimal system for the same daily load profile. Upon comparison of the two systems, the following observations were made; the system capacity reduced from 8.4 kW to 4.3 kW, the initial cost and the net present cost of the optimal system reduced by 48% and 41.5% respectively, system capacity shortage was slightly improved from 9.5% to 8.8%. The costs of energy (COE) improved from 0.793 kWh to 0.742 kWh, 6.4% reduction. The results indicate that, the proposed design method reduces the system capacity by almost half which significantly reduced the system initial cost by 41.5 percent.

Design of a Hybrid Power System for Electrification of New Talkha Bridge Construction in Egypt. (Dept. E )

This paper aims to introduce an effective design of a stand-alone hybrid power system (HPS). The designed system consists of a photovoltaic (PV) array, battery bank and diesel generator. The presented technique proceeds in practical and plausible steps to estimate the rated powers of each component of the HPS. It will be determinant based on the expected loads, characteristics of the used PV module and the meteorological data of the region of installation. Furthermore, it can be applied to design a hybrid power system for electrification of any individual load either in rural or urban areas which are near to the main grid. Thereupon, it is applied on a case study (Constructing of New Talkha Bridge in Egypt). Additionally in this paper, various operational configurations are studied, analyzed economically to ascertain which of them the optimal and appropriate considering cost, reliable and pollutant emissions are. The results of the study encouraged the use of the hybrid PV system in rural areas in Egypt.

Optimal Sizing of a Stand-Alone Hybrid Power System Based on Battery/Hydrogen with an Improved Ant Colony Optimization

A distributed power system with renewable energy sources is very popular in recent years due to the rapid depletion of conventional sources of energy. Reasonable sizing for such power systems could improve the power supply reliability and reduce the annual system cost. The goal of this work is to optimize the size of a stand-alone hybrid photovoltaic (PV)/wind turbine (WT)/battery (B)/hydrogen system (a hybrid system based on battery and hydrogen (HS-BH)) for reliable and economic supply. Two objectives that take the minimum annual system cost and maximum system reliability described as the loss of power supply probability (LPSP) have been addressed for sizing HS-BH from a more comprehensive perspective, considering the basic demand of load, the profit from hydrogen, which is produced by HS-BH, and an effective energy storage strategy. An improved ant colony optimization (ACO) algorithm has been presented to solve the sizing problem of HS-BH. Finally, a simulation experiment has been done to demonstrate the developed results, in which some comparisons have been done to emphasize the advantage of HS-BH with the aid of data from an island of Zhejiang, China.

Generation-scheduling-coupled battery sizing of stand-alone hybrid power systems

Properly sizing the battery energy storage system (BESS) of a stand-alone hybrid power system is an important step to guarantee its reliability and low cost. This study applies the technique of storage-integrated generation scheduling using metaheuristics to the BESS sizing, which helps to achieve the optimal scheduling scheme for each sizing plan, as its advantage over the rule-based sizing method. Such technique incorporates the storage dispatch with the scheduling of the dispatchable generators, and is formulated and solved as an optimisation with metaheuristics. Compared with existing approaches of storage-integrated generation scheduling, the metaheuristics-enabled approach proposed here relieves the modelling complexity of the optimisation, by using fewer decisions variables. Different degrees of solar and wind, as the renewable energy, are penetrated into the system, together with traditional diesel generators. The mixed-coded non-dominated sorting genetic algorithm II (NSGA-II) is employed as the main numeric tool, which shows the advantage of mixed-coded modelling over the real-coded modelling for the generation scheduling problem. The numeric evaluation of the system planning adopts the levelised cost of electricity (LCOE) as the economic indicator, to guide the real system planning and operation.

Analysis of Standalone Analysis of Standalone Hybrid Power Systems with reference to the Reactive Power Management

Standalone hybrid systems are need of the hour in electrical power sector. The reactive power support is most vital issue in the voltage point of view.Wind energy has received the special attention of researchers in recent times. Attempts to generate electricity from wind energy have been made since the end of nineteenth century. A single renewable energy source may not be able to meet the load demands apart from the fact that continuous supply of energy may not be ensured. Here comes the importance of Hybrid energy systems such as Wind-diesel, Wind-PV.Advanced FACTS technologies have utilized for reactive power support to the system. The fuzzy logic has implemented in the control circuit of STATCOM which is relatively advantageous compared to conventional PI controller. The control strategy is verified through model simulation study whose results conform the significance of the control methodology incorporated in the paper.

Application of the Hybrid Big Bang–Big Crunch algorithm for optimal sizing of a stand-alone hybrid PV/wind/battery system

In this paper an efficient method based on Hybrid Big Bang–Big Crunch (HBB–BC) algorithm is presented for optimal sizing of a stand-alone hybrid power system including photovoltaic panel, wind turbine and battery bank. The optimization is carried out to continuously satisfy the load demand with minimizing the total present cost (TPC) of the system. TPC includes all the costs throughout the useful life of the system, which are translated to the initial moment of the investment. In the optimization problem, the reliability index of energy not supplied (ENS) is also considered to have a reliable system. The HBB–BC algorithm is an effective and powerful method that has high accuracy and fast convergence as well as its implementation is easy. This algorithm using the Particle Swarm Optimization (PSO) capacities improves the capability of the Big Bang–Big Crunch (BB–BC) algorithm for better exploration. In addition, the HBB–BC uses a mutation operator after position updating to avoid local optimum and to explore new search areas. This study is applied to a village in Qazvin, Iran that still lacks access to grid electricity due to economic and geography issues. The performance of the proposed algorithm is compared with PSO and Discrete Harmony Search (DHS) algorithms. Simulation results confirm that HBB–BC algorithm with high accuracy can find the optimal solution and it has the best performance in comparison with two mentioned algorithms.