Energy Generation System Research Articles

ENERGY MANAGEMENT IN HYBRID PV-WIND-BATTERY STORAGE-BASED MICROGRID USING MONTE CARLO OPTIMIZATION TECHNIQUE

The paper presents an efficient energy management system designed for a small-scale hybrid microgrid incorporating wind, solar, and battery-based energy generation systems using three types of Monte Carlo simulation techniques. The heart of the proposed system is the energy management system, which is responsible for maintaining power balance within the microgrid. The EMS continuously monitors variations in renewable energy generation and load demand and adjusts the operation of the energy conversion systems and battery storage to ensure optimal performance and reliability. The primary objective of the energy management system is to maintain power balance within the microgrid, even in the face of fluctuations in renewable energy generation and load demand. This involves dynamically adjusting the operation of the renewable energy sources and battery storage system to match the instantaneous power requirements of the microgrid. Overall, the paper presents a comprehensive approach to designing and implementing the Monte Carlo technique to extract maximum energy profit using the hybrid microgrid. By integrating renewable energy sources with energy storage and advanced control algorithms, the proposed system aims to enhance the reliability, stability, and sustainability of the microgrid's power supply.

Cooperative Control Strategy for Power Quality Based on Heterogeneous Inverter Parallel System

Multi-functional grid-connected inverters (MFGCIs) have attracted much attention for their auxiliary services to improve power quality in microgrids and new energy generation systems. However, power quality enhancement based on MFGCIs often only considers a single control method. The regulation potential of multiple control-type inverters is not fully utilized. To suppress harmonic and support voltage, a cooperative control strategy based on the parallel system of a grid-following (GFL) inverter and a grid-forming (GFM) inverter is proposed. The topology of the MFGCIs is introduced and a mathematics model is deduced. Secondly, a specific-order harmonic compensation method is proposed for the harmonic suppression at the point of common coupling (PCC). The harmonic current is realized to be shared according to the inverter capacity. The reactive power output of the heterogeneous inverters is coordinated by calculating the reactive power compensation and reactive power allocation so that the PCC voltage always stays near the rated voltage. Finally, the effectiveness of the proposed control strategy is verified by simulation and experiment.

Photocatalytic water splitting for large-scale solar-to-chemical energy conversion and storage

Sunlight-driven water splitting allows renewable hydrogen to be produced from abundant and environmentally benign water. Large-scale societal implementation of this green fuel production technology within energy generation systems is essential for the establishment of sustainable future societies. Among various technologies, photocatalytic water splitting using particulate semiconductors has attracted increasing attention as a method to produce large amounts of green fuels at low cost. The key to making this technology practical is the development of photocatalysts capable of splitting water with high solar-to-fuel energy conversion efficiency. Furthermore, advances that enable the deployment of water-splitting photocatalysts over large areas are necessary, as is the ability to recover hydrogen safely and efficiently from the produced oxyhydrogen gas. This lead article describes the key discoveries and recent research trends in photosynthesis using particulate semiconductors and photocatalyst sheets for overall water splitting, via one-step excitation and two-step excitation (Z-scheme reactions), as well as for direct conversion of carbon dioxide into renewable fuels using water as an electron donor. We describe the latest advances in solar water-splitting and carbon dioxide reduction systems and pathways to improve their future performance, together with challenges and solutions in their practical application and scalability, including the fixation of particulate photocatalysts, hydrogen recovery, safety design of reactor systems, and approaches to separately generate hydrogen and oxygen from water.

Collaborative water-electricity operation optimization of a photovoltaic/pumped storage-based aquaculture energy system considering water evaporation effects

The increasing global population, economic development, and urbanization trends have led to a heightened demand for seafood, presenting a significant challenge to the growth trajectory of the food industry. As the most rapidly expanding segment within the food industry, aquaculture presents a sustainable solution to mitigate the overexploitation of marine resources and address the growing demand for food. Aquaculture's sufficient aquatic expanses offer considerable potential for PV deployment, thereby relieving the demand for limited land resources. However, existing research rarely addresses the collaborative operation of water and electricity in aquaculture systems. The effects of water evaporation from PV panel-covered water surfaces on the collaborative water-electricity operation are generally neglected. Hence, this work proposes a collaborative water-electricity operation of a photovoltaic (PV)-pumped storage-based aquaculture energy system considering the water evaporation effects. This optimization method accounts for the reduced water evaporation due to PV panel shading. Water surface PV and pumped storage are integrated into the system to fulfill electricity needs, with pumped storage serving as a dual-purpose device for water and electricity supply. Environmentally sustainable water-electricity generation and aquaculture energy system requirements are established. Water surface PV electricity generation is modeled based on climate and engineering conditions, while aquaculture pond electricity requirement includes oxygenation, feeding, and water replenishment. Finally, a collaborative water-electricity operation model is introduced to optimize operation strategies for various devices. A case study on a fish-light complementation project demonstrates that this optimization method can reduce reliance on the utility grid and overall system operational costs.

The Development of an Advanced Facade Map: An Evolving Resource for Documenting Case Studies

This paper describes the creation and the potentials of an online tool to identify and document case studies that demonstrate perceived best practices in the design and implementation of advanced, sustainable, and climate-responsive integrated buildings facades. The project was created to catalog these projects in sufficient detail to allow users—expected to include design professionals, students, and faculty—to discover and study relevant examples, based on key project features, defined by the authors as technologically advanced and worthy of relevance: daylight and solar control, natural ventilation, noise control, embodied carbon, energy generation, and innovative insulation systems. The website documenting 44 case study buildings and this paper provides a preliminary overview about how it was made, what it is, and what some potential uses of the tool might be. This study emphasizes adaptability across climates, showcasing sustainable facades designed to balance energy efficiency with occupant comfort. This study also shows how data can be analyzed through the Map, based on four case studies. Presenting these statistics, the resource offers a foundation for exploring facade technologies that support sustainable building practices and respond effectively to climate-specific challenges. In doing so, the authors aim to inspire further exploration of innovative facade solutions within the context of sustainable building practices.

IOT-based monitoring and control system for renewable energy generation

IOT-based monitoring and control system for renewable energy generation

Thermo-Economic and Environmental Assessment of a Novel SOFC-Based Hybrid Energy Generation System for Combined Cooling Heating and Power Generation

Thermo-Economic and Environmental Assessment of a Novel SOFC-Based Hybrid Energy Generation System for Combined Cooling Heating and Power Generation

Scaling up small wind turbines in India: Barriers and options for the way forward

Small wind turbines (SWTs) are an adaptable and flexible option for the generation of renewable electricity. They can be sited at locations with a reasonable wind resource that are unsuitable for large wind projects. SWTs, whether operating individually or as hybrids, are also classified as distributed renewable energy generation (DREG) systems. Hence, in addition to improving the utilization of wind and expanding renewable capacity in line with the 2030 500 GW targets (PIB Delhi 2021), SWTs can also support the Indian government’s plans to promote DREG for livelihood applications and contribute toward distributed renewable purchase obligation (RPO) targets.

Theoretical analysis of organic Rankine cycle for maximum power generation in optimization operation conditions

The global critical issue in energy scarcity should be appropriately solved to realize a sustainable society. Effective use of Rankine cycle is one possible way since it provides most of worldwide electricity production. In this paper, theoretical analysis model of organic working fluids R717, R134a, R1234yf, R290, R245fa and R1233zd in Rankine cycle for maximum power generation in optimization operation using low-temperature heat sources are proposed and studied for development next generation green and zero-carbon energy generation system to promote the race to zero. Results show that temperatures of warm and cold water at inlet, mass flow rate of the warm water and performance of the evaporator play a key role to obtain the theoretical optimization operation conditions for maximum power generation. In the case of same initial conditions of temperatures of warm water (85 Celsius degree) and cold water (15 Celsius degree) at inlet, mass flow rate of the warm water (10 ​kg/s) and performance of the evaporator (100 ​kW/K), R717 has the best performance in terms of the maximum power output 56.0 ​kW with thermal efficiency of 8.6%, and the next is the R1233zd (54.4 ​kW, 8.3%), R245fa (54.0 ​kW, 8.2%), R134a (52.8 ​kW, 7.9%), R290 (52.7 ​kW, 7.9%), and R1234yf (51.7 ​kW, 7.7%). Here, it should be noticed that other optimization conditions are almost the same (mass flow rate of the cold water 9.1–9.2 ​kg/s; performance of the condenser 91∼92 ​kW/K) to get their maximum power output of ORC. In addition, it also known that low-GWP R1233zd (GWP: 1) can deserve the best option to replace R245fa (GWP: 950) and R1234yf (GWP: 4) also can replace r134a (GWP: 1430) since their optimization operation conditions are almost same.

Designing tariff for charging electric vehicles at home with equity in mind – The tripartite tariff

Extant electricity tariffs model an industrial age when electricity predominantly came from centralised conventional generators, and they still model the pre-pandemic years when virtually everyone shared similar work pattern of working from dawn to dusk. The extant home electricity tariffs offer off-peak electricity mainly during night hours. The tripartite tariff – a home Electric Vehicle (EV) charging tariff that offers off-peak EV charging opportunities during daytime and night hours – is presented. The objective is to assess how access to a tripartite tariff impacts an individual worker's ability to charge their EV at home using off-peak electricity and implications in cognizance of a democratised next generation energy system desirable in an heterogenous society. Using 15 user profiles that represent low-income, middle-income, and high-income earners, working at different times of the day within four successive weeks, the tripartite tariff is designed for inclusive EV charging. With a traditional tariff regime – which represents existing off-peak electricity tariffs – the low-income earners who would typically need off-peak EV charging the most tend to have the least access to it. The tripartite tariff offers inclusive EV charging opportunity at lower off-peak rates for every worker category: night-time, daytime, and mix daytime-and-nighttime workers.

Micro Gas Turbines in the Global Energy Landscape: Bridging the Techno-Economic Gap with Comparative and Adaptive Insights from Internal Combustion Engines and Renewable Energy Sources

This paper investigates the potential of Micro Gas Turbines (MGTs) in the global shift towards low-carbon energy systems, particularly focusing on their integration within microgrids and distributed energy generation systems. MGTs, recognized for their fuel flexibility and efficiency, have yet to achieve the commercialization success of rival technologies such as Internal Combustion Engines (ICEs), wind turbines, and solar power (PV) installations. Through a comprehensive review of recent techno-economic assessment (TEA) studies, we highlight the challenges and opportunities for MGTs, emphasizing the critical role of TEA in driving market penetration and technological advancement. Comparative analysis with ICE and RES technologies reveals significant gaps in TEA activities for MGTs, which have hindered their broader adoption. This paper also explores the learning and experience effects associated with TEA, demonstrating how increased research activities have propelled the success of ICE and RES technologies. The analysis reveals a broad range of learning and experience effects, with learning rates (α) varying from 0.1 to 0.25 and experience rates (β) from 0.05 to 0.15, highlighting the significant role these effects play in reducing the levelized cost of energy (LCOE) and improving the net present value (NPV) of MGT systems. Hybrid systems integrating MGTs with renewable energy sources (RESs) and ICE technologies demonstrate the most substantial cost reductions and efficiency improvements, with systems like the hybrid renewable energy CCHP with ICE achieving a learning rate of α = 0.25 and significant LCOE reductions from USD 0.02/kWh to USD 0.017/kWh. These findings emphasize the need for targeted TEA studies and strategic investments to unlock the full potential of MGTs in a decarbonized energy landscape. By leveraging learning and experience effects, stakeholders can predict cost trajectories more accurately and make informed investment decisions, positioning MGTs as a competitive and sustainable energy solution in the global energy transition.

Combining energy generation and radiant systems: Challenges and possibilities for plus energy buildings

Radiant heating and cooling (RHC) systems are being more widely adopted considering the well-known technical advantages: increased thermal comfort, space saving, and reduced energy use. Since the building sector is currently one of the largest consumers of fossil fuels, many directives and regulations have been enacted to address the intense concern about energy use for space conditioning.Even though radiant systems are considered as an energy efficient technology for building heating and cooling, more effort is needed to fulfil the zero energy requirements outlined by recent standards and directives. Renewable Energy Sources (RES) are an effective solution to avoid using finite fossil fuels and related geopolitical issues enhanced by the recent world conflicts. Despite being primarily intermittent and subject to economic and regional constraints, RES offer suitable temperature levels to supply low temperature heating and high temperature cooling operation, a major advantage of RHC system.Although a limited number of studies directly report energy savings or CO2 emission reduction as the main outcomes of the research related to this combination, valuable insights have been obtained for the present review. Primary energy can decrease between 40% and 80% with different integration of RHC, photovoltaic, heat pumps and district heating. TABS can lead to load shifting up to 100%, allowing an increased self −consumption of renewable energy.This paper provides evidence on whether coupling radiant systems with renewables is a promising strategy for achieving nearly-zero annual energy balances in building stocks. It investigates recent trends, limitations and potential to support decarbonization goals.

A non-isolated converter of switching current stress in DC-DC converter for integrating PV and battery storage system

ABSTRACT High-gain DC-DC converters have seen significant adoption in renewable energy systems like Photovoltaic (PV), Fuel Cells (FC), and other systems. However, their effectiveness is increasingly tied to the availability of renewable resources. As Renewable Energy Sources (RES) typically generate electricity at low voltage levels, integrating high-gain DC-DC converters with RES is crucial for optimal performance. This paper introduces an innovative DC-DC converter design that achieves high gain and is specifically able to integrate smoothly with RES like PV systems and battery storage. The innovation of the proposed converter lies in its integration of conventional boost and buck-boost converters, enabling a high voltage gain while minimizing output voltage ripple and reducing switch current stress. Additionally, its unidirectional power transfer port allows efficient energy flow from solar PV or battery sources to the load, making it highly adaptable for managing fluctuating energy sources, a feature that distinguishes it from current modern converters. Its design simplifies architecture by combining traditional converter types, reducing the number of components, which leads to cost savings, lower weight, and improved reliability. Additionally, the design minimizes output voltage ripple and reduces switching current stress, enhancing the converter’s durability under variable operating conditions. The converter’s performance is evaluated through simulation and experimental studies, demonstrating a 96.3% efficiency and 5.5 times of voltage gain. The converter’s feasibility and effectiveness are validated under dynamic scenarios with varying solar irradiation, making it an ideal solution for clean energy generation systems, including hybrid energy generation setups. The proposed converter topology offers an auspicious solution for high-gain DC-DC conversion in renewable energy systems.

Integrated PV energy generation system with high-gain converter and CHHO-FLC-based MPPT for grid integration

Integrated PV energy generation system with high-gain converter and CHHO-FLC-based MPPT for grid integration

Design and simulation of a photovoltaic plant for maximum use of the solar resource in the Toluviejo municipality of Colombia

Currently, there are various technologies for constructing photovoltaic plants including monofacial and bifacial photovoltaic panels, centralized and string-type inverters, and fixed mounting structures with light followers, to build electrical energy generation systems. This work reviewed the advantages and disadvantages between these technologies, and the implementation of a photovoltaic plant in Toluviejo, Colombia was proposed. To justify and confirm the design, simulations were carried out with the PVsyst software, resulting in the bifacial panels, centralized inverters, and structures with light followers, the most effective solution, and with the highest production for the proposed photovoltaic power generation plant.

ENERGY MANAGEMENT IN HYBRID PV-WIND-BATTERY STORAGE-BASED MICROGRID USING DROOP CONTROL TECHNIQUE

The paper presents an efficient energy management system designed for a small-scale hybrid microgrid incorporating wind, solar, and battery-based energy generation systems using the droop control technique. The heart of the proposed system is the energy management system, which is responsible for maintaining power balance within the microgrid. The EMS continuously monitors variations in renewable energy generation and load demand and adjusts the operation of the energy conversion systems and battery storage to ensure optimal performance and reliability. The primary objective of the energy management system is to maintain power balance within the microgrid, even in the face of fluctuations in renewable energy generation and load demand. This involves dynamically adjusting the operation of the renewable energy sources and battery storage system to match the instantaneous power requirements of the microgrid. Overall, the paper presents a comprehensive approach to designing and implementing an efficient energy management system for a small-scale hybrid wind-solar-battery-based microgrid to extract maximum profit from electricity generation. By integrating renewable energy sources with energy storage and advanced control algorithms, the proposed system aims to enhance the reliability, stability, and sustainability of the microgrid's power supply.

Modeling and Simulation of an Integrated Synchronous Generator Connected to an Infinite Bus through a Transmission Line in Bond Graph

Most electrical energy generation systems are based on synchronous generators; as a result, their analysis always provides interesting findings, especially if an approach different to those traditionally studied is used. Therefore, an approach involving the modeling and simulation of a synchronous generator connected to an infinite bus through a transmission line in a bond graph is proposed. The behavior of the synchronous generator is analyzed in four case studies of the transmission line: (1) a symmetrical transmission line, where the resistance and inductance of the three phases (a,b,c) are equal, which determine resistances and inductances in coordinates (d,q,0) as individual decoupled elements; (2) a symmetrical transmission line for the resistances and for non-symmetrical inductances in coordinates (a,b,c) that result in resistances that are individual decoupled elements and in a field of inductances in coordinates (d,q,0); (3) a non-symmetrical transmission line for resistances and for symmetrical inductances in coordinates (a,b,c) that produce a field of resistances and inductances as individual elements decoupled in coordinates (d,q,0); and (4) a non-symmetrical transmission line for resistances and inductances in coordinates (a,b,c) that determine resistances and inductance fields in coordinates (d,q,0). A junction structure based on a bond graph model that allows for obtaining the mathematical model of this electrical system is proposed. Due to the characteristics of a bond graph, model reduction can be carried out directly and easily. Therefore, reduced bond graph models for the four transmission line case studies are proposed, where the transmission line is seen as if it were inside the synchronous generator. In order to demonstrate that the models obtained are correct, simulation results using the 20-Sim software are shown. The simulation results determine that for a symmetrical transmission line, currents in the generator in the d and q axes are −25.87 A and 0.1168 A, while in the case of a non-symmetrical transmission line, these currents are −26.14 A and 0.0211 A, showing that for these current magnitudes, the generator is little affected due to the parameters of the generator and the line. However, for a high degree of non-symmetry of the resistances in phases a, b and c, it causes the generator to reach an unstable condition, which is shown in the last simulation of the paper.

Decommissioning of a fuel oil-fired thermoelectric power plant in Brazil - Economic feasibility under certain and risk conditions

The strategic analysis for the decommissioning of thermoelectric plants is seen as a trend for the coming years. The search for renewable alternatives should stimulate investment in other energy sources, reducing the number of thermoelectric plants in the energy generation system. However, few studies have dealt with the decommissioning of oil-fired thermoelectric plants. In this work, the methodology was applied under deterministic and stochastic conditions using methods of net present value (NPV), internal rate of return (IRR), discounted payback, capital asset pricing model (CAPM) and weighted average cost of capital (WACC). The results showed that the deterministic NPV was positive, ranging from R$101.30 million (pessimistic scenario) to R$109.73 million (optimistic scenario). The IRR was higher than the WACC of 10.55 %, ranging from 13.50 % to 13.68 % per year. For the Monte Carlo simulation, NPV was observed with 100 % certainty of viability and the probabilities of occurrence allowed more analysis of the risks involved than those obtained by deterministic methods. this study contributes to future decommissioning projects in Brazil, considering the scenario of stimulating renewable sources and the energy transition, helping managers make decisions about their projects. In addition, it helps guide public policies that can optimize the decommissioning process and strengthen the national energy sector.

A nanofluidic chemoelectrical generator with enhanced energy harvesting by ion-electron Coulomb drag

A sufficiently high current output of nano energy harvesting devices is highly desired in practical applications, while still a challenge. Theoretical evidence has demonstrated that Coulomb drag based on the ion-electron coupling interaction, can amplify current in nanofluidic energy generation systems, resulting in enhanced energy harvesting. However, experimental validation of this concept is still lacking. Here we develop a nanofluidic chemoelectrical generator (NCEG) consisting of a carbon nanotube membrane (CNTM) sandwiched between metal electrodes, in which spontaneous redox reactions between the metal and oxygen in electrolyte solution enable the movement of ions within the carbon nanotubes. Through Coulomb drag effect between moving ions in these nanotubes and electrons within the CNTM, an amplificated current of 1.2 mA cm−2 is generated, which is 16 times higher than that collected without a CNTM. Meanwhile, one single NCEG unit can produce a high voltage of ~0.8 V and exhibit a linear scalable performance up to tens of volts. Different from the other Coulomb drag systems that need additional energy input, the NCEG with enhanced energy harvesting realizes the ion-electron coupling by its own redox reactions potential, which provides a possibility to drive multiple electronic devices for practical applications.

Optimal dimensioning of renewable energy generation and storage systems

With high energy demand and large available area, agricultural farms offer significant potential for renewable energy investments, like photovoltaic systems and electrical energy storages. However, the profitability of such investments depends strongly on self-consumption, so accurate planning requires computation-intensive simulation and optimization considering local consumption. This study presents a novel methodology for the optimal dimensioning and configuration of photovoltaic systems and electrical energy storages using efficient techniques from continuous non-linear optimization. Combining physical and economic models with measured consumption data, an investment’s net present value over 20 years is maximized. Using gradient-based solver WORHP, the simulation, optimal control, and optimal dimensioning of the local energy system are calculated simultaneously, allowing for efficient computation over an entire year of hourly data to capture both daily and seasonal variations.The approach is demonstrated with simple use cases, including an exemplary day of a dairy farm’s consumption, for which optimal systems with and without storage achieve 77% and 43% of autarky, respectively. Saturation effects of optimal plant size can be observed when sizes are large enough for optimal self-consumption but not expanded further for grid export. With energy storage, this saturation is reached at higher values. Optimizing photovoltaic plants with different orientations to match the specific consumption patterns characteristic of the dairy farm achieves similar autarky as a single plant while reducing investment costs by more than 20%. While thorough validation and comparison against heuristic methods predominantly used in the field is part of ongoing research, the presented use cases demonstrate the flexibility and efficiency of the proposed method and highlight its promise as a planning tool in the agricultural domain and beyond.