Distributed generation integrated with thermal unit commitment considering demand response for energy storage optimization of smart grid

This paper deals with an optimal battery energy storage capacity for the smart grid operation. Distributed renewable generator and conventional thermal generator are considered as the power generation sources for the smart grid. Usually, a battery energy storage system (BESS) is used to satisfy the transmission constraints but installation cost of battery energy storage is very high. Sometimes, it is not possible to install a large capacity of the BESS. On the other hand, the competition of the electricity market has been increased due to the deregulation and liberalization of the power market. Therefore, the power companies are required to reduce the generation cost in order to maximize the profit. In this paper, a thermal units commitment program considers the demand response system to satisfy the transmission constraints. The BESS capacity can be reduced by the demand response system. The electric vehicle (EV) and heat pump (HP) in the smart house are considered as the controllable loads of the demand side. The effectiveness of the proposed method is validated by extensive simulation results which ensure the reduction of BESS capacity and power generation cost, and satisfy the transmission constraints.     

Design and optimum energy management of a hybrid renewable energy system based on efficient various hydrogen production

Utilizing renewable energy resources is one of the convenient ways to reduce greenhouse gas emissions. However, the intermittent nature of these resources has led to stochastic characteristics in the generation and load balancing of the microgrid systems. To handle these issues, an energy management optimization for microgrids operation should be done to urge the minimization of total system costs, emissions, and fuel consumption. An optimization program for decreasing the operational cost of a hybrid microgrid consisting of photovoltaic array, wind unit, electrolyzer, hydrogen storage system, reformer, and fuel cell is presented. Two different methods of producing hydrogen are considered in this study to ensure the effectiveness of the developed methodology. In the microgrid system with high penetration of renewable energy resources, using storage technologies to compensate for the intermittency of these resources is necessary. To evaluate the functioning of the microgrid system, a mathematical model for each source is developed to coordinate the system operation involving energy conversion between hydrogen and electricity. Particle Swarm Optimization Algorithm is utilized to determine the optimum size and operational energy management within the system. It is evident from the results that there is about a 10% reduction in the amount of CH₄ consumption in reformer when the electrolyzer was employed in the system. It is observed that the CH₄ reduction in summer and fall is higher than other seasons (10.6% and 11.5%, respectively). The reason is that the highest RES production occurs in these seasons during a year. It is also worth mentioning that the electrolyzer technology would play a significant role in decreasing the CH₄ consumption in the microgrid system.     

Hydrogen fuel as an important element of the energy storage needs for future smart cities

A considerable amount of non-dispatchable photovoltaic and wind power have always been planned in smart cities, however, the problem of massive energy storage has not yet been solved which limits the use of green energy on larger scale. At present the only battery energy storage is available, and it is effective only for storing modest quantities of energy for short periods of time. The other storage technology options are not often commercially available items; rather, they are just good concepts that need to be tested for viability. Currently, the only alternative options for turning an urban development into one that exclusively uses green energy is to use that energy to generate hydrogen through electrolyzers, then use this fuel to generate the required electricity in order to stabilize the grid. Even more appealing is the idea of using wind and photovoltaic energy to transform smart communities into a centre for producing hydrogen in addition to a city that solely uses renewable energy. The most likely solution, absent an urgent debate inside the science establishment, will be to import electricity from the burning of hydrocarbons while continuing to pay carbon offsets, which is incompatible with the goal of using only renewables. The smart city has not officially accepted this issue, just like the science establishment.     

Consumer engagement: An insight from smart grid projects in Europe

This paper provides an insight into consumer engagement in smart grid projects in Europe. Projects analysed are those included in the catalogue annexed in the JRC Report “Smart Grid projects in Europe: lessons learned and current developments”. The analysis suggests an increase in the interest in consumer engagement projects at European level and a strong focus on the residential sector, and emphasises the key importance of public funding to support these projects. The study also reveals that projects involving consumers are characterised by the pursuit of two main objectives: gaining deeper knowledge of consumer behaviour (observing and understanding the consumer) and motivating and empowering consumers to become active energy customers (engaging the consumer). The paper reviews the main activities undertaken to obtain these objectives and highlights trends and developments in the field. Finally, the paper discusses obstacles to consumer engagement and the strategies adopted by the projects surveyed to tackle them, highlighting the need to build consumer trust and to design targeted campaigns taking into consideration different consumer segments. The conclusions are in line with findings and analyses presented in the literature and underscore the need for further research and action at European level.     

Hydrogen energy storage integrated hybrid renewable energy systems: A review analysis for future research directions

Hydrogen energy storage systems (HydESS) and their integration with renewable energy sources into the grid have the greatest potential for energy production and storage while controlling grid demand to enhance energy sustainability. This paper presents a bibliometric analysis based on a comprehensive review of the highly cited articles on HydESS to provide a detailed insight into future directions and applications. The study was carried out by using the Scopus database search engine to look for filtered keywords in the HydESS and related research. It can be demonstrated that the HydESS literature expanded rapidly from 2016 to 2021 compared to 2011 to 2015. It is found that 89.17% of published articles explained control and test systems-based methods, whereas 10.83% of publications discuss review assessments. Our analysis of highly cited articles on HydESS highlights several aspects, such as methods and systems, issues, difficulties, and challenges to establishing current constraints and research gaps. This evaluation can enhance operational performance, environmental friendliness, energy savings, uninterrupted power supply service, cost benefits, on-site generation, and adaptability. It would be beneficial for technology development and the growth of the hydESS industry. This study may act as a guideline not only for academics in determining the line of research and generating additional discoveries, but also for the government in formulating financial strategies.     

Optimal management of microgrids including renewable energy scources using GPSO-GM algorithm

Environmentally friendly energy sources with high power quality or reliability and low costs are regarded as an effective solution for energy supply problems arising from use of conventional methods. Presented in this paper, gives an optimal management strategy of PV/wind/diesel independent hybrid systems for supplying required energy in autonomous microgrids. A new optimization problem is formulated for minimizing the capital investment and fuel costs of the system. To solve the proposed optimization problem a novel algorithm, named Guaranteed convergence Particle Swarm Optimization with Gaussian Mutation (GPSO-GM), is developed. Two operators, namely mutation and guaranteed convergence, are added to PSO in order to help finding more accurate results and increasing the speed of calculations. The performance of the proposed strategy is evaluated in two case studies.     

Toward a hydrogen society: Hydrogen and smart grid integration

Hydrogen has an important role as a smart solution for Smart Grid, as it can play as an energy vector, a storage medium, and a clean fuel cell. The integration of Hydrogen and Smart Grid can minimize the impact on the environment while maximizing sustainability, which indicates that we are developing toward a hydrogen society. There have been already many studies on different aspects of this topic. For a better understanding of the related work, this paper proposed a comprehensive overview of the related work on the integration of Hydrogen and Smart Grid. Related literature is organized and analyzed from four categories, including Hydrogen energy in smart grids, Hydrogen fuel cell electric vehicles, Hydrogen economy in smart grids, and Models for energy system in smart grids. And each subject has been introduced more carefully. What's more, for a clear understanding for readers, we provide overall scenario views for the organization of the related work.     

Operational performance of energy storage as function of electricity prices for on-grid hybrid renewable energy system by optimized fuzzy logic controller

Realization of benefits from on-grid distributed generation based on renewable energy sources requires employment of energy storage to overcome the intermittency in power generation by such sources, while accounting for time-varying electricity prices. The objective of this study is to examine the effects of time-varying electricity prices on the performance of energy storage components for an on-grid hybrid renewable energy system (HRES) utilizing an optimized fuzzy logic controller (FLC). To achieve the objective, FLC membership functions are optimized for minimizing the operational cost of the HRES based on weekly and daily prediction of data for grid electricity price, electrical load, and environmental parameters, including wind speed, solar irradiation, and ambient temperature, using shuffled frog leap algorithm. FLC three inputs include (a) grid electricity price, (b) net power flow as the difference between energy produced and energy consumed, and (c) state of charge (SOC) of battery stack. It is confirmed that accounting for grid electricity price has considerable effects on the performance of energy storage components for operation of on-grid HRES, as the weekly and daily optimized FLCs result in less working hours for fuel cell and electrolyzer and less fluctuations in SOC of battery stack.     

Optimal and stochastic performance of an energy hub-based microgrid consisting of a solar-powered compressed-air energy storage system and cooling storage system by modified grasshopper optimization algorithm

Simultaneous operation of different energy generation and transmission infrastructures is a subject that has been considered under the concept of energy hub. This subject is highly regarded in the field of microgrids. One of the basic issues for investors is to properly utilize the energy hub for optimally managing energy carriers, especially in the energy price prediction. In the present paper, a new strategy is introduced for the energy hub in order to achieve the optimal performance of a microgrid (MG) that includes different energy carriers for each day. The objective of this strategy is to minimize the operation cost and consider the environmental issues. The proposed energy hub consists of a combined cooling-heating-power (CCHP) system along with a wind turbine and photovoltaic cells. The studied energy hub system is composed of an ice storage conditioner (ISC) system and an energy storage system (ESS) as the energy storage resource (ESR). One of the goals of the present work is to investigate the effect of solar-powered compressed-air energy storage (SPCAES) on the performance of the energy hub. The proposed strategy takes into account the uncertainty of the energy resources such as the wind and sun for meeting the electric, thermal, and cooling needs in different scenarios. In the present paper, to produce various scenarios, the Latin hypercube sampling (LHS) method is used. Also, the k-means method is used to reduce the number of scenarios. The objective function is solved using the modified grasshopper optimization algorithm (MGOA). According to the modeling results, the ESS can exhibit successful performance in the energy management strategy.     

Optimal sizing study of hybrid wind/PV/diesel power generation unit

In this paper, a methodology of sizing optimization of a stand-alone hybrid wind/PV/diesel energy system is presented. This approach makes use of a deterministic algorithm to suggest, among a list of commercially available system devices, the optimal number and type of units ensuring that the total cost of the system is minimized while guaranteeing the availability of the energy. The collection of 6 months of data of wind speed, solar radiation and ambient temperature recorded for every hour of the day were used. The mathematical modeling of the main elements of the hybrid wind/PV/diesel system is exposed showing the more relevant sizing variables. A deterministic algorithm is used to minimize the total cost of the system while guaranteeing the satisfaction of the load demand. A comparison between the total cost of the hybrid wind/PV/diesel energy system with batteries and the hybrid wind/PV/diesel energy system without batteries is presented.The reached results demonstrate the practical utility of the used sizing methodology and show the influence of the battery storage on the total cost of the hybrid system.     

A new ship energy management algorithm to the smart electricity grid system

In this paper, a new energy management algorithm has been suggested for the ships connected with alternative energies considering the smart electricity grid features. The algorithm focuses on the use of optimum energy source on the shipboard based on the priorities of authorities such as the most economic, environmental, or both criteria at the ports. The algorithm is performed in MATLAB, and several case studies are simulated to validate the results. The 5 maritime nations, which are at different regions: United States, Belgium, Turkey, China, and Australia, are taken into account in the case studies. The actual data of a bulk carrier ship have been used to achieve tangible results in the simulations. The results of the case studies are compared to determine the changes of energy cost and released emission to meet demand of electricity on the ships. Capital cost of the proposed concept is also given to make an economic evaluation. The results show that the ship energy management algorithm provides the significant economic and environmental advantages. This paper aims to contribute to the importance of the ships in the smart electricity grid concept for the maritime and electricity sector representatives.     

Implementation of self-adaptive Harris Hawks Optimization-based energy management scheme of fuel cell-based electric power system

This paper presents a hybrid Fuel Cell-based Power System (FCPS) consisting of fuel cell and hybrid Energy Storage Systems (ESSs), including a battery with high energy density and supercapacitor with high power density to overcome the sudden load demand change and improving the reliability of the delivered power. Any hybrid power system needs Energy Management Strategies (EMS) to balance the power between the different energy sources. In this paper, a comparative analysis of three energy management strategies, including the state machine control method, the classical PI control method and equivalent consumption minimization strategy (ECMS) is performed. The paper's main objective is enhancing the DC-bus voltage profile of a hybrid fuel cell/battery/supercapacitor power system equipped with the developed under-mentioned EMS by using a hybrid modified optimization technique that combines Harris Hawks optimization (HHO) and Sine Cosine Algorithm (SCA). The new hybrid HHO-SCA is employed to determine the optimal control parameters of the DC-bus voltage controller, which significantly assists in enhancing the DC-bus voltage profile as well as the performance of the applicable ESS in terms of improving efficiency and SoC. The effectiveness of the suggested control schemes is simulated using MATLAB/SIMULINK software. The simulation results confirmed that the proposed HHO-SCA is superior and efficient in improving the DC-bus voltage.     

Optimal management of hydrogen storage in stochastic smart microgrid operation

This paper presents an energy management and reserve scheduling scheme in order to optimally operate a 17-bus Low Voltage (LV) grid-tied microgrid, powered by photovoltaics, a wind turbine and a Fuel Cell (FC) utilizing on site hydrogen production and storage. Since high Renewable Energy Resources (RES) penetration is assumed, the expected deviations due to their intermittency are accounted for by the reserve provision by the FC system, in order to deviate as little as possible from the scheduled energy demand injected by the upstream grid. All these are incorporated into the operating cost of the microgrid assuming penalization of unscheduled power injections from the grid. The intermittency of RES and load are incorporated in the model by assuming known probability density functions for the forecasting errors. Then, energy and reserve scheduling is performed utilizing the Harmony Search algorithm in order to minimize the expected operating costs of the examined system by optimal reserve and energy provision from the stored/generated hydrogen. For that purpose, hourly optimizations are performed for a given year to assess the value on-site hydrogen generation and FC technologies add to microgrid operation and Distributed Generation (DG) in general. The purpose is to prove the use of hydrogen storage systems in effective uncertainty balancing. The hydrogen storage system appears to effectively counter the intermittency of renewables in moderate penetration, reducing the uncertainty costs. In higher renewable penetrations, due to uncertainty being already accounted for by the storage, the benefits of the RES penetration are even greater.     

Management of natural gas resources and search for alternative renewable energy resources: A case study of Pakistan

Energy usage in Pakistan has increased rapidly in past few years due to increase in economic growth. Inadequate and inconsistent supply of energy has created pressure on the industrial and commercial sectors of Pakistan and has also affected environment. Demand has already exceeded supply and load shedding has become common phenomenon. Due to excessive consumption of energy resources it would become difficult to meet future energy demands. This necessitates proper management of existing and exploration of new energy resources. Energy resource management is highly dependent on the supply and demand pattern. This paper highlights the future demands, production and supply of energy produced from natural gas based on economic and environmental constraints in Pakistan with special emphasis on management of natural gas. An attempt has been made by proposing a suitable course of action to meet the rising gas demand. A mechanism has been proposed to evaluate Pakistan's future gas demand through quantitative analysis of base, worst and best/chosen option. CO₂ emission for all cases has also been evaluated. The potential, constraints and possible solutions to develop alternative renewable energy resources in the country have also been discussed. This work will be fruitful for the decision makers responsible for energy planning of the country. This work is not only helpful for Pakistan but is equally important to other developing countries to manage their energy resources.     

Beyond smart grids - The need of intelligent energy networks for a higher global efficiency through energy vectors integration

From the energy point of view, the season we have been living more and more seems the era of sources diversification. The most correct scenario for a sustainable energy future foresees no predominance of one source over the others in any area of the world but a proper energy mix, based on locally available resources and needs.The concept and role of energy vectors is key: “(an energy vector) allows transfer, in space and time, a given quantity of energy, hence making it available for use distantly in time and space from the point of availability of the original source”. Therefore, a scenario that gives full scope for the ES to be immune from the characteristics of non-sustainable resource consumption and waste production, the system itself must shift the focus from resources to vectors (mainly electricity, hydrogen, heat).Smart grids have been largely indicate, in this context, as an answer for their characteristic “needful design” to move from the “old” grids (unidirectional power flows) to “new” bi-directional electricity networks. This is not enough: the real need is for an intelligent management of a complete set of energy sources and vectors, as electricity, heat, hydrogen, bio and non-biofuels, that requires a clear shift that goes beyond smart grids and looks at Intelligent Energy Networks.     

An energy management approach for renewable energy integration with power generation and water desalination

The share of the renewable energy sources (RES) in the global electricity market is substantially increasing as a result of the commitment of many countries to increase the contribution of the RES to their energy mix. However, the integration of RES in the electricity grid increases the complexity of the grid management due to the variability and the intermittent nature of these energy sources. Energy storage solutions such as batteries offer either short-term storage that is not sufficient or longer period storage that is significantly expensive. This paper introduces an energy management approach which can be applied in the case of power and desalinated water generation. The approach is based on mathematical optimization model which accounts for random variations in demands and energy supply. The approach allows using desalination plants as a deferrable load to mitigate for the variability of the renewable energy supply and water and/or electricity demands. A mathematical linear programming model is developed to show the applicability of this idea and its effectiveness in reducing the impact of the uncertainty in the environment. The model is solved for the real world case of Saudi Arabia. The optimal solution accounts for random variations in the renewable energy supply and water and/or electricity demands while minimizing the total costs for generating water and power.     

Predictive energy management for a wind turbine with hybrid energy storage system

Hybrid energy storage systems (HESSs) help mitigating the fluctuations and variable availability of certain renewable sources, such as wind power, as they can provide support in different time scales. Therefore, regulating their state-of-charge (SOC) becomes crucial to ensure that the hybrid system complies with generation commitments agreed in time-ahead markets despite subsequent unexpected wind speed variations. So far, research has been mainly targeted at avoiding extreme SOC situations in the storage devices, whereas the regulation of this parameter to specific values has often been disregarded. A novel approach is proposed in this work, where model predictive control (MPC) is used to regulate the SOC of a HESS under variable wind and grid demand scenarios. The MPC-based supervisory controller developed for the hybrid system has been implemented and simulated under different situations. This controller monitors the future variation of the SOC with the aim of having the HESS available to develop its assigned functions successfully. The results show that a proper regulation of the SOC in the HESS increases the capacity to manage the active power supplied to the grid by the hybrid system based on wind power, as well as the level of compliance with generation commitments established time ahead.     

HIES: Cases for hydrogen energy and I-Energy

With the increasing demand for electricity, more and more fossil fuels are used to generate electricity which leads to energy shortage and environmental pollution. Therefore, using Renewable Energy Sources (RESs) and developing sustainable smart grid have become a common global priority: Since RESs, like solar and wind energy, are inherently unstable, hydrogen energy, as a completely clean new energy, has received widespread attention: I-Energy, which combines information and energy, is a new research direction in smart grid. Furthermore, the household electricity usage accounts for 41% of the total power consumption. Therefore, Household Intelligent Electricity System (HIES), combining hydrogen energy and i-Energy, becomes smart solutions. In this paper, we review the scientific literature for hydrogen energy and i-Energy on HIES, including recognition of electricity appliances, establishment of power consumption model, human activity analysis, smart interactive terminal, home energy management system, distributed power supply and district coordinated power utilization. Finally, we summarize the challenges and give the solutions concerning HIES, and this work can give a useful reference to new energy used model and environment protection.     

Evaluation of distributed building thermal energy storage in conjunction with wind and solar electric power generation

Energy storage is often seen as necessary for the electric utility systems with large amounts of solar or wind power generation to compensate for the inability to schedule these facilities to match power demand. This study looks at the potential to use building thermal energy storage as a load shifting technology rather than traditional electric energy storage. Analyses are conducted using hourly electric load, temperature, wind speed, and solar radiation data for a 5-state central U.S. region in conjunction with simple computer simulations and economic models to evaluate the economic benefit of distributed building thermal energy storage (TES). The value of the TES is investigated as wind and solar power generation penetration increases. In addition, building side and smart grid enabled utility side storage management strategies are explored and compared. For a relative point of comparison, batteries are simulated and compared to TES. It is found that cooling TES value remains approximately constant as wind penetration increases, but generally decreases with increasing solar penetration. It is also clearly shown that the storage management strategy is vitally important to the economic value of TES; utility side operating methods perform with at least 75% greater value as compared to building side management strategies. In addition, TES compares fairly well against batteries, obtaining nearly 90% of the battery value in the base case; this result is significant considering TES can only impact building thermal loads, whereas batteries can impact any electrical load. Surprisingly, the value of energy storage does not increase substantially with increased wind and solar penetration and in some cases it decreases. This result is true for both TES and batteries and suggests that the tie between load shifting energy storage and renewable electric power generation may not be nearly as strong as typically thought.     

Balancing energy and environment: The effect and perspective of management instruments in China

The rapid growth of Chinese economy has tremendously stimulated the expansion of energy consumption. The structure of energy consumption in China is featured with the coal domination. Air pollution is becoming increasingly severe. As a result, we are confronted with the extremely arduous task to balance energy consumption and environmental protection. In order to coordinate the relationship between energy consumption and environmental protection in a strategic way, this paper analyzes comprehensively the instruments, effects and perspectives of energy-related environmental management. Meanwhile, this paper illustrates the barriers and challenges facing the energy and energy-related environmental management in China, and suggests a priority strategy of management instrument, mainly composed of energy-saving, optimization of energy structure, promulgation of environmental standards, advance in environmental technologies, internalization of environmental costs, establishment of a public benefit fund and adoption of a Renewable Portfolio System.