Decentralized Energy Sources Research Articles

Perspectives on NO X Emissions and Impacts from Ammonia Combustion Processes.

Climate change and global warming necessitate the shift toward low-emission, carbon-free fuels. Although hydrogen boasts zero carbon content and high performance, its utilization is impeded by the complexities and costs involved in liquefaction, preservation, and transportation. Ammonia has emerged as a viable alternative that offers potential as a renewable energy storage medium and supports the global economy's decarbonization. With its broader applicability in large power output applications, decentralized energy sources, and industrial locations off the grid, ammonia is increasingly regarded as an essential fuel for the future. Although ammonia provides a sustainable solution for future low-carbon energy fields, its wide-scale adoption is limited by NO X emissions and poor combustion performance under certain conditions. As research on ammonia combustion expands, recent findings reveal factors impacting the chemical reaction pathways of ammonia-based fuels, including the equivalence ratio, fuel mixture, pressure, and temperature. Investigations into ammonia combustion and NO X emissions, at both laboratory and industrial scales, have identified NO X production peaks at equivalence ratios of 0.8-0.9 for ammonia/hydrogen blends. The latest studies about the NO X emissions of the ammonia flame at different conditions and their generating pathways are reviewed in this work. Effective reduction in NO production from ammonia-based flames can be achieved with richer blends, which generate more NH i radicals. Other advanced NO X mitigation techniques such as plasma-assisted combustion have been also explored. Further research is required to address these challenges, reduce emissions, and improve efficiencies of ammonia-based fuel blends. Finally, the extinction limit of ammonia turbulent flame, its influential factors, and different strategies to promote the ammonia flame stability were discussed. The present review contributes to disseminating the latest advancements in the field of ammonia combustion and highlights the importance of refining reaction mechanisms, computational models, and understanding fundamental phenomena for practical implications.

ELECTRICAL ENGINEERING IN RENEWABLE ENERGY SYSTEMS: A REVIEW OF DESIGN AND INTEGRATION CHALLENGES

As the global pursuit of sustainable energy intensifies, the integration of renewable energy sources into existing power systems has become a critical focal point for electrical engineers. This review explores the challenges and advancements in the field of Electrical Engineering concerning the design and integration of renewable energy systems. The transition from traditional fossil fuels to renewable sources, such as solar, wind, and hydroelectric power, necessitates a comprehensive understanding of the intricate engineering aspects involved. The first section of the review delves into the design challenges faced by electrical engineers when developing efficient and reliable renewable energy systems. This encompasses the optimization of power generation from intermittent sources, the enhancement of energy conversion technologies, and the development of energy storage solutions to mitigate the inherent variability of renewables. Cutting-edge design methodologies and innovative materials are discussed to highlight the ongoing efforts to improve the performance and reliability of renewable energy systems. The second section focuses on the integration challenges encountered during the incorporation of renewable energy into existing power grids. Grid stability, power quality, and the management of decentralized energy sources pose significant hurdles. Electrical engineers are addressing these challenges through the implementation of advanced control systems, smart grid technologies, and energy management strategies. The review also explores the role of energy storage systems and the potential of emerging technologies like microgrids in facilitating seamless integration. Furthermore, the review examines the interdisciplinary nature of electrical engineering in the context of renewable energy, emphasizing the collaboration between electrical engineers, environmental scientists, and policymakers. The synergy between these disciplines is crucial for developing holistic solutions that address not only technical challenges but also environmental and regulatory considerations. This review provides a comprehensive overview of the design and integration challenges faced by electrical engineers in the realm of renewable energy systems. By understanding and overcoming these challenges, the global community can accelerate the transition towards a sustainable and resilient energy future.
 Keywords: Renewable energy, Energy Integration, Challenges, Electrical, Engineering, Review.

Ukraine’s energy supply in the defense sector: The first lessons of war

The terrible consequences of the Russian-Ukrainian war, which continues on the territory of the Ukrainian land, and the consequences of natural disasters indicate the need to create alternative (reserve or emergency) sources of energy supply for enterprises, institutions, and individual households, and objects of small forms of management, especially outside the points of permanent deployment. Ensuring an uninterrupted and stable electricity supply to all these forms is an extremely important problem for Ukraine as the country faced a large number of challenges regarding energy independence due to numerous missile strikes. The purpose of the study was to analyze the energy system and the level of damage to Ukraine after the Russian missile attacks, the impact on the state of energy supply of individual facilities and consumers of military camps, examine the possibilities of using emergency and backup energy sources and alternative energy, in particular, solar and wind. The study analyses the destruction of the energy system of Ukraine as a result of missile attacks and the possibilities of using emergency and backup energy sources and alternative energy, in particular, solar and wind, and the investigation of the potential and opportunities to attract investment in the field of alternative energy. Special attention is paid to small business facilities, including military camps. In the course of the study, it was determined that Ukraine has a geographical location that provides space for the installation of various alternative energy systems and the possibility of combining them to diversify and improve the stability and reliability of the Ukrainian energy system. The practical importance of the study lies in the ability to make more informed decisions regarding the implementation of programs aimed at switching to alternative and decentralized energy sources. This will make the country’s energy infrastructure more stable and allow better meeting the energy needs of small forms of management, individual farms, military units, formations, and infrastructure facilities.

A Review on Energy Management of Community Microgrid with the use of Adaptable Renewable Energy Sources

The main objective of this paper is to review the energy management of a community microgrid using adaptable renewable energy sources. Community microgrids have grown up as a viable strategy to successfully integrate renewable energy sources (RES) into local energy distribution networks in response to the growing worldwide need for sustainable and dependable energy solutions. This study presents an in-depth examination of the energy management tactics employed in community microgrids using adaptive RES, covering power generation, storage, and consumption. Energy communities are an innovative yet successful prosumer idea for the development of local energy systems. It is based on decentralized energy sources and the flexibility of electrical users in the community. Local energy communities serve as testing grounds for innovative energy practices such as cooperative microgrids, energy independence, and a variety of other exciting experiments as they seek the most efficient ways to interact both internally and with the external energy system. We discuss several energy management tactics utilized in community microgrids with flexible RES, Which include various renewable energy sources (wind, solar power, mechanical vibration energy) and storage devices. Various energy harvesting techniques have also been discussed in this paper. It also includes information on various power producing technology. Given the social, environmental, and economic benefits of a particular site for such a community, this paper proposes an integrated technique for constructing and efficiently managing community microgrids with an internal market. The report also discusses the obstacles that community microgrids confront and proposed methods for overcoming them. This paper analyzes future developments in community microgrids with adaptive RES. The study discusses potential developments in community microgrids with flexible energy trading systems.

Evaluation of Fuzzy-Based Artificial Neural Network for Power Quality Enhancement

The rapid integration of renewable and decentralized energy sources is transforming the operation of power networks, leading to challenges in efficient electricity utilization, optimal harnessing of renewable energy, and maintaining stable voltage levels. To tackle these issues, clusters of multi-renewable energy systems are interconnected through electrical converters employing fuzzy controllers. Power quality (PQ) controllers have been developed for various renewable energy sources to meet the growing energy demands. Enhancing power electronics separation based on power storage and distributed generation offers significant opportunities for managing PQ. This research focuses on improving the performance of smart hybrid multi-renewable energy systems using microgrids through the utilization of artificial neural networks (ANNs). The proposed approach incorporates a fuzzy controller-based pulse generation technique for a DC-to-AC inverter, ensuring efficient power conversion while maintaining PQ factors. The fuzzy controller effectively handles stringent constraints on process parameters by leveraging adjustable variables. Hardware evaluation and performance analysis were conducted using a peripheral interface controller (PIC) controller, providing an accurate representation of the results.

Studies on Performance of Distributed Vertical Axis Wind Turbine under Building Turbulence

As a part of the new energy development trend, distributed power generation may fully utilize a variety of decentralized energy sources. Buildings close to the installation location, besides, may have a considerable impact on the wind turbines’ operation. Using a combined vertical axis wind turbine with an S-shaped lift outer blade and Φ-shaped drag inner blade, this paper investigates how a novel type of upstream wall interacts with the incident wind at various speeds, the influence region of the turbulent vortex, and performance variation. The results demonstrate that the building’s turbulence affects the wind’s horizontal and vertical direction, as well as its speed, in downstream places. The wall’s effect on wind speed changing in the downstream area is thoroughly investigated. It turns out that while choosing an installation location, disturbing flow areas or low disturbing flow zones should be avoided to have the least impact on wind turbine performance.

Decentralized energy: a prerequisite for the distribution of decentralized technology

The emergence of decentralized technology has brought about significant advancements in various industries, promising increased transparency, efficiency, and trust in transactions and data exchange. However, for decentralized technology to truly flourish and realize its full potential, it is crucial to establish a foundation of decentralized energy sources. This article explores the critical relationship between decentralized energy and the distribution of decentralized technology. By examining the limitations of centralized energy systems, the benefits of decentralized energy, and the synergies between decentralized energy and technology, we highlight the necessity of decentralized energy as a prerequisite for the widespread adoption of decentralized technology.

The value of TSO-DSO coordination in re-dispatch with flexible decentralized energy sources: Insights for Germany in 2030

As Germany plans to raise the share of energy consumption satisfied by Renewable Energy Sources (RES) up to 65%, congestion in the transmission grids will drastically increase in the power system unless the grids are substantially upgraded or new flexibility options are considered. In this paper, we explore possible integration mechanisms of a potentially powerful source of flexibility: Distributed Energy Resources (DERs). Currently, there is no advanced regulatory system for including them into the established electricity markets. We investigate the application of load flexibility DERs can provide for assisting the re-dispatch necessary in electricity markets that employ a zonal pricing mechanism. We implement two different cases with varying levels of involvement of the DSOs and compare their performance with a business-as-usual case in one scenario from 2015 and one prediction for 2030. Findings include that while both cases facilitate the system-wide re-dispatch concerning volume and cost, the average value of optimal load-shifting is not high enough in 2015 to incentivize investment in this area. However, at the higher percentages of generation from RES in the future scenario, this value becomes promising and using DERs for this purpose may provide long-term benefits to the system operators and owners of assets alike.

TECHNICAL AND ECONOMIC DEVELOPMENT MECHANISMS OF LOCAL ENERGY SUPPLY SYSTEMS (MICROGRID)

The business model of energy as a service (Energy-as-a-service, EaaS) is considered as a direction of development of the concept of 3D (Decarbonization, Decentralization, Digitalization) and the conceptual model of the Internet of energy. At the same time, EaaS is formed in the form of a "package" service model, in which the customer is provided with hardware and software and energy services. EaaS solutions should include consumption management and energy efficiency services, promote the introduction of renewable energy sources (RES) and other decentralized energy sources, and optimize the balance between supply and demand in the electricity market. EaaS is shown to be a broad term for service-driven business models with innovative potential to transform the energy industry
 To assess the specifics of EaaS application to Microgrid, the construction and operation of Microgrid as a local power system or power supply system, which is a technological complex consisting of generation facilities (energy sources), energy flexibility sources and electricity consumers, which are collected under a single management ensuring the most efficient and consumer-friendly energy supply. It is determined that the technological guarantee of the efficiency of modern Microgrid is the ability to integrate and optimally combine different energy sources and flexibility, as well as the presence of a single control loop that allows the best use of these sources.
 Smart Grid as a Service (SGaaS) based on Service-Oriented Architecture is presented. The SGaaS hierarchical architecture provides a promising three-tier architecture that includes an intelligent network level for global optimization, such as minimizing global protection or global costs, a level of coordination to maintain reliability and security in the Smart Grid, and a Microgrid level to monitor end-user device status.
 The implementation of the EaaS and SGaaS mechanisms has stimulated the development of Microgrid as a Service (MaaS) - as a service that offers the deployment of Microgrid, reducing the initial cost of investment and complexity. MaaS has been identified as a new flagship funding mechanism that allows organizations to deploy Microgrid without any prior investment, as a solution that does not require advance capital for energy consumers and focuses on results such as on-site energy. MaaS mechanisms offer customers more control over their energy needs, enabling them to increase the sustainability and reliability of their energy supply, balance energy use, achieve clean energy goals and explore other innovative products and services.

Particle Swarm Optimization in Residential Demand-Side Management: A Review on Scheduling and Control Algorithms for Demand Response Provision

Power distribution networks at the distribution level are becoming more complex in their behavior and more heavily stressed due to the growth of decentralized energy sources. Demand response (DR) programs can increase the level of flexibility on the demand side by discriminating the consumption patterns of end-users from their typical profiles in response to market signals. The exploitation of artificial intelligence (AI) methods in demand response applications has attracted increasing interest in recent years. Particle swarm optimization (PSO) is a computational intelligence (CI) method that belongs to the field of AI and is widely used for resource scheduling, mainly due to its relatively low complexity and computational requirements and its ability to identify near-optimal solutions in a reasonable timeframe. The aim of this work is to evaluate different PSO methods in the scheduling and control of different residential energy resources, such as smart appliances, electric vehicles (EVs), heating/cooling devices, and energy storage. This review contributes to a more holistic understanding of residential demand-side management when considering various methods, models, and applications. This work also aims to identify future research areas and possible solutions so that PSO can be widely deployed for scheduling and control of distributed energy resources in real-life DR applications.

Utility-Scale Shared Energy Storage: Business models for utility-scale shared energy storage systems and customer participation

Due to climate change, supply scarcity, and society’s desire to expand access to electricity and improve energy-system resilience, there has been an increasing demand to invest in and use renewable energy sources (RESs) that are environmentally friendly, efficient, sustainable, and affordable. This has diversified and decentralized energy sources and increased their penetration. However, the variability and intermittency of RESs has introduced new challenges to power system operators, such as the requirement for high ramping rates when solar energy declines in the afternoon, known colloquially as the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">duck curve</i> , voltage and frequency fluctuations, and reduced overall system inertia. In response to these challenges, energy storage systems (ESSs) (devices such as batteries, energy management, and energy conditioning) have become crucial components to the reliable and stable operation of modern power systems. ESSs can tackle the aforementioned challenges to seamlessly integrate RESs into the power grid. They can help system operators to smooth the output power of RESs and provide grid services, such as voltage and frequency regulation, peak load shaving, phase balancing, energy arbitrage, expansion deferral, and so on.

Power loss and voltage stability optimization with meta-heuristic algorithms in power system

Power flow, which is one of the most prominent problems in the field of power system, is the calculation of the voltage amplitudes and phase angles of each bus and the power losses by using the bus data with known steady state voltage amplitudes and power values. Increasing demand and the connection of decentralized energy sources to the power system at various points make more complicated power flow problem. The power flow problem is of great importance for both electricity generation and transmission. Planning new loads that can be connected to the system in the future and using the existing transmission lines at full capacity are based on the solution of the power flow problem. Power flow, which is a nonlinear problem, has traditionally been solved using numerical methods such as Newton-Raphson and Gauss Seidel. However, the success of classical solution algorithms decreases depending on the conditions of the power system. Meta-heuristic optimization techniques and search algorithms developed in recent years show that better results can be obtained in solving the power flow problem. In this study, Artificial Bee Colony (ABC), Gray Wolf (GWO), Particle Swarm Optimization (PSO) and Newton Raphson algorithms have been applied to optimize the power flow problem in the IEEE-14 bus test power system created using Matlab software. The performance of the algorithms has been compared by considering the voltage amplitudes, voltage deviation, phase angles, power losses and calculation times obtained from the model power system.

Evaluating Distribution System Operators: Automated Demand Response and Distributed Energy Resources in the Flexibility4Chile Project

The mission of distribution system operators (DSOs) is to operate and manage distribution networks in a safe and secure manner. DSOs are also responsible for developing distribution grids to ensure the long-term ability of a system to deliver high-quality services to users and other stakeholders of the electric power system. Traditionally, DSOs have carried out their mission through adequate network operation and planning. However, the profound transformation of the energy system that is currently taking place worldwide creates new challenges for DSOs to carry out their responsibilities in a cost-efficient and secure manner. A significant number of renewable energy sources (RESs) are already connected, and more are expected in the future. Furthermore, the number of electric vehicles (EVs) and public charging stations will see a major increase in the coming years. These trends are coupled with an exponential technological evolution that enables decentralized energy sources to be connected at lower voltages and, at the same time, enables customers to interact with the market in response to grid conditions.

Study of the short-circuit currents in branches of distribution networks with trilateral power supply

The article presents the determination of the short-circuit currents in distribution networks with trilaterally power supplied branches – form a supplying substation and two decentralized energy sources. After connecting decentralized energy sources, branches with bilateral and trilateral power supply appear. This changes the network configuration and, respectively, its mode parameters, and also requires adjustments to the settings of the relay protection.

RELaTED, decentralized & renewable Ultra Low Temperature District Heating, concept conversion from traditional district heating

District Heating (DH) are a very efficient system for heating in urban areas and they are considered as key elements for the de-carbonization of the European Cities. High performance levels and low operational energy costs are part of the identity of these heating networks. The reduction of supply-line temperatures allows the possibility to introduce new low-grade and renewable source energy production, reducing dependence on fossil fuel-based energy plants. Moreover, heat-losses in distribution pipelines are also reduced, since the gradient temperature between supply line and ambient temperature is reduced. Operation of decentralized & Ultra Low Temperature (ULT) systems may adapt for the introduction of weather-dependent, distributed heat sources such as solar systems. Furthermore, although very dependent on local availability, waste heat streams from commercial and industrial installations are also considered because of the stability of heat supply all year round, resulting in minimally carbon intensive processes. Regarding building features, the reduced heat load derived from the transition from current buildings to Nearly Zero Energy Buildings (NZEB), RELaTED allows for the novel concept called prosumer, where buildings can deliver energy to the grid from decentralized energy sources installed in the building. In RELaTED, different subsystems are being developed by different industrial partners, to prove their efficiency in 4 real demonstration sites: Tartu (Estonia), Belgrade (Serbia), Vinge (Denmark) and Iurreta (Spain). A 3-FS (3-Function Scheme) DH substation that permits buildings to become prosumers. Two types of solar collectors, one is an all polymeric glazed collector and the second one is an unglazed collector, both as components of Building Integrated Large Solar Thermal Systems (BILSTS) solar loop. Finally, a reversible and high efficiency heat pump for domestic hot water is being developed. In this paper, an approach to ULT concept is studied, including transitory phases of the conversion.

Study on Grid-Connected Strategy of Distribution Network with High Hydropower Penetration Rate in Isolated Operation

As the largest global renewable source, hydropower is a useful supplement to mountainous distribution networks with abundant water resources, and shoulders a large portion of the regulation duty in many power systems. In particular, in the form of decentralized energy sources located to their customers, small hydropower (SHP) improve grid stability by diversifying the electricity system and reducing power loss. The mountainous distribution networks supplied by small hydropower are closed-loop design but open-loop operation, which easily causes the tripping of tie line even further the off-grid operation of small hydropower system. Once the tie line trips, the current countermeasures—such as hydropower shutdown and load shedding—do not fully guarantee the reliability of power supply and the utilization efficiency of hydropower. This paper studies the amplitude-frequency characteristics of SHP off-grid, according to the typical integration of hydropower in South China, a SHP on-grid/off-grid model is established based on the Power Systems Computer Aided Design (PSCAD) platform. It is found that due to the inertia of SHP, the amplitude-frequency characteristics of SHP island system are relatively slow, and the process of non-synchronization with the main grid is gradually expanded. The characteristic of SHP has a certain degree of synchronization with the main grid in the initial island operates stage, which helps to find a novel grid connection method. This paper further proposes the strategy of using fast busbar automatic transfer switch (BATS), which quickly connect the trip-off SHP to the distribution network under the condition of permitting distributed energy grid-connected. The PSCAD simulation results show that proposed strategy has a limited impact on the power grid and prove the effectiveness of the method.

Turning a Liability into an Asset

President Jokowi has promised to add 35 GW of power to the national grid, while the Ministry of Energy and Mineral Resources wants to source 23% of its power from renewable sources by 2025. It will be difficult to reconcile these two goals as the majority of Indonesia’s 35 GW is expected to come from high-capacity coal and gas-fired plants on Java and Sumatra. This runs the risk of both undershooting the renewables goal and neglecting the more remote provinces in eastern Indonesia that rely mainly on imported diesel fuel. With a shrewd policy aproach, this could pose an opportunity to begin developing small-scale renewable power sources – such as solar, wind, and biomass gasification – in more remote parts of Indonesia where natural resources are plentiful and large-scale fossil fuel plants are impractical. This would allow PLN to both boost the share of renewables in the energy mix and acquire experience running flexible micro-grids capable of managing diverse and decentralized energy sources. This would put Indonesia ahead of the curve, as efficient grids that can draw power from a wide range of sources will likely play a big role in the future of energy policy. If PLN continues to focus narrowly on high-capacity gas and coal plants, it will risk getting locked into an inflexible, high-carbon structure ill-suited for the needs of the 21st century. The limits of such a model are already showing in the United States.&#x0D; Keywords: Infrastructure, energy policy, renewables, smart grid, PLN

Efficient energy use and storage practices within residential facilities for compliance with the nZEB criteria

Solar energy, today, is the leader in renewable energy and the world's increasing new energy source. In 2016, for the first time, newly installed photovoltaic capacity has increased by more than 50%, exceeding the new coal-fired power stations capacity established worldwide. At the beginning of the year, the European Parliament agreed the target that 35% renewable sources by 2030. Studies show that by 2050 approximately 45% of all the households in the EU could produce their own renewable energy and more than a third of them could be part of a renewable energy cooperative, despite the worries of the distribution companies. Furthermore, the EPBD directive (EU) - Energy Performance of Buildings pushes towards new and more performing buildings - nearly zero energy buildings (nZEB) - where energy efficiency and energy flexibility are essential to achieve the required performance targets. Nearly zero-energy buildings (NZEBs) have very high energy performance and could be achieved through the integration of renewable and decentralized energy sources, continuous grid optimization and the inclusion of increasing numbers of consumers becoming producers, so called prosumers. So far, the photovoltaic system is the single technology that can combine data from utility networks with household consumption and therefore should be considered a starting point for streamlining the electricity consumption and production which will be imposed by strict regulations.

Power-to-gas and the consequences: impact of higher hydrogen concentrations in natural gas on industrial combustion processes

Operators of public electricity grids today are faced with the challenge of integrating increasing numbers of renewable and decentralized energy sources such as wind turbines and photovoltaic power plants into their grids. These sources produce electricity in a very inconstant manner due to the volatility of wind and solar power which further complicates power grid control and management. One key component that is required for modern energy infrastructures is the capacity to store large amounts of energy in an economically feasible way.One solution that is being discussed in this context is “power-to-gas”, i.e. the use of surplus electricity to produce hydrogen (or even methane with an additional methanation process) which is then injected into the public natural gas grid. The huge storage capacity of the gas grid would serve as a buffer, offering benefits with regards to sustainability and climate protection while also being cost-effective since the required infrastructure is already in place.One consequence would be, however, that the distributed natural gas could contain larger and fluctuating amounts of hydrogen. There is some uncertainty how different gas-fired applications and processes react to these changes. While there have already been several investigations for domestic appliances (generally finding that moderate amounts of H2 do not pose any safety risks, which is the primary focus of domestic gas utilization) there are still open questions concerning large-scale industrial gas utilization. Here, in addition to operational safety, factors like efficiency, pollutant emissions (NOX), process stability and of course product quality have to be taken into account.In a German research project, Gas- und Wärme-Institut Essen e. V. (GWI) investigated the impact of higher and fluctuating hydrogen contents (up to 50 vol.-%, much higher than what is currently envisioned) on a variety of industrial combustion systems, using both numerical and experimental methods. The effects on operational aspects such as combustion behavior, flame monitoring and pollutant emissions were analyzed.Some results of these investigations will be presented in this contribution.

Solar Photovoltaic and Wind Energy Providing Water.

Renewable energy technologies can make a major contribution to universal access to both energy and water in a sustainable way. In many regions of the world with energy poverty there are abundant renewable energy sources. In this review it is described how solar photovoltaic (PV) and wind energy have a huge potential to supply clean water, in particular in areas with no grid connection. Off‐grid technologies can form a significant part of the solution, all the way from household level to village or community level. Small scale off‐grid systems can provide not only lighting but also energy for pumping to gain access to water and to purify and re‐use water. In rapidly growing peri‐urban areas electric power grids may be available but need to be complemented with decentralized energy sources. Solar and wind can be part of a new kind of hybrid energy supplies. It is noted that there is a confluence of factors, such as greater urbanization, population increase, economic development that will determine the energy mix. The United Nations Sustainable Development Goals of clean water and energy for all are strongly related and will depend to a large extent on solar PV and wind.