Sustainable Electricity System Research Articles

Electric vehicle and photovoltaic advanced roles in enhancing the financial performance of a manufacturing and commercial setup

Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network.

Performance Evaluation of Overcurrent Relay and Ground Fault Relay Coordination in Distribution Feeder

Reliable and sustainable electrical distribution systems require effective protection measures against internal and external disturbances, especially short-circuit disturbances, to avoid damage to the equipment. Overcurrent relays (OCR) and ground fault relays (GFR) play an important role in the safety of the distribution network. To improve performance, evaluation of relay coordination is essential. During the short circuit, the nearest relay to the fault point is activated first and the backup relay is activated if the fault current exceeds the adjustment of the main relay. Coordination ensures that timely signaling is sent to interrupt the circuit. Inspection of the OCR relay revealed that it did not comply with the IEC 60255 standard and consequently adjusted the classification time to 0.402 seconds. Similarly, the results of the GFR relay inspection did not meet the standards and required an adjustment of the evaluation time to 0.492 seconds. Resolving these deviations is crucial to maintaining the reliability and compliance of the distribution network with industry standards, ensuring that the protection relays respond quickly and effectively to disturbances, thereby preventing possible damage to equipment

Implementation cost of net zero electricity system: Analysis based on Korean national target

We evaluated the costs of implementation of a sustainable electricity system with carbon net zero emission by 2050. To achieve this goal, it is assumed to reduce the use of fossil fuel-based power generation, increase carbon-free clean energy generation, and secure storage facilities. We compared the total costs including the capital cost of new generators and storage technologies, fuel costs, and emission costs by 2050. We also investigated the effects of various levels of carbon price, curtailment rates of renewable energy output, demand pattern shift, increasing nuclear power generation, building pumped hydro storage, and utilization of hydrogen storage as long-duration storage. One of our findings indicates that although a higher curtailment rate necessitates increased renewable energy installation to achieve national emission target, it leads to a reduction in total costs due to the decreased requirement for storage capacity. Our findings provided invaluable insights into the potential of these solutions to facilitate the transition to a more sustainable electricity system in South Korea and other countries with similar policy goals.

Metal-Organic Frameworks Based Autonomous Water Harvesting & Sustainable Energy Generation from Ambient Air

Recently, hydro-electric nanotechnology is touted as promising next-generation renewable energy because it can employ environmentally friendly sources for producing electricity. However, conventional hydro-electric nanotechnology is hampered by limitations, such as artificial induction of water stream and a low production level of energy. In this work, we developed an autonomous water harvesting & sustainable electrical energy generation system that overcomes the limitations of conventional renewable energy. Autonomous water harvesting & sustainable electrical energy generation system was successfully achieved with two distinctive metal-organic frameworks (MOFs), that are, an amine-functionalized Zr-based MOF (UiO-66-NH2) particles for atmospheric water harvesting, and a highly conductive Ni3(HITP)2 (HITP = 2,3,6,7,10,11-hexaiminotriphenylene) MOF-grown cotton-fabric for producing electrical energy. The environmentally responsive UiO-66-NH2 harvests water from airborne air and the condensed water spontaneously produces electrical potential between wet- and dry-Ni3(HITP)2, resulting in electrical energy generation with a maximum power and energy densities of 2.6 μW cm-3 and 1.1 mJ cm-3, respectively. Our integrated water harvesting and energy generation systems can pave the way for realizing a hydro-electric nanogenerator as a next-generation energy harvesting system. Figure 1

Datasheet-Based Efficiency Comparison Analysis of Alternating Current (AC) And Direct Current (DC) Electrical Systems

In today's electrical infrastructure, a significant portion continues to depend on the AC (alternating current) system, necessitating energy conversion from DC (direct current) to AC during power generation and vice versa when reaching consumers. Nonetheless, as renewable energy sources and DC-based electronic devices gain popularity, the DC electrical system presents an attractive alternative. This research compares the energy efficiency between AC and DC electrical systems in school buildings. Through literature review and energy analysis in school buildings, the study found that the DC electrical system is significantly more efficient, achieving an efficiency rate of 89%. In contrast, the AC system only reaches 84%. The implications of this research provide valuable insights for implementing more efficient and sustainable electrical systems in buildings in the future.

The unfolding low-carbon transition in the UK electricity system.

The paper explores three periods in the UK electricity consumption-production system since World War II. The first two involved the development of an increasingly centralized, integrated system that provided electricity to meet growing post-war demand. It saw two major changes in governance, first to nationalization, then to privatization and liberalization. The third period started at the turn of the Century, driven by increasing evidence of the impact of fossil fuels on the Earth's climate. The paper focuses on the drivers of change, within the UK and externally, and how they affected governance, technology deployment, and industry structure. It draws on the multi-level perspective and the concepts of governance and technological branching points to inform the analysis of each period. It shows that there is a considerable distance to travel toward a truly sustainable electricity system.

Transforming the grid for a more environmentally and socially sustainable electricity system in Great Britain is a slow and uneven process.

Electricity system decarbonization is key for environmental sustainability. From a consumption-production perspective, much attention has been paid to changes in how electricity is generated and used, but electricity systems also rely on a grid infrastructure that connects and integrates production and consumption, and which will also need to transform. At the same time, new technologies in the electricity system, including the grid, offer the potential for more socially sustainable ways of producing and consuming energy. However, in practice, change has been slow, uneven, and often dysfunctional. A socio-technical transitions approach offers insights into why this is so, seeing electricity system change not simply in technical and economic terms, but also as the outcomes of interactions between technology and social and political processes. The approach draws attention to the particular challenges of achieving rapid transitions in complex critical infrastructures like electricity with strong institutional logics of security. This article applies this approach to the case of Great Britain, where despite strong commitments to sustainability in the form of high-level climate policy, the electricity grid has often been a constraint on the pace of change. The nature of the British transition is explained partly by weak links between these high-level goals on the one hand and the detailed rules and practices in the electricity system on the other. It is also explained by patterns of ownership and grid regulation in the British case that protect incumbents and make it difficult for new actors to develop the system in more socially sustainable directions.

Exploring sustainable electricity system development pathways in South America’s MERCOSUR sub-region

We explore sustainable electricity system development pathways in South America’s MERCOSUR sub-region under a range of techno-economic, infrastructural, and policy forces. The MERCOSUR sub-region includes Argentina, Brazil, Chile, Uruguay, and Paraguay, which represent key electricity generation, consumption, and trade dynamics on the continent. We use a power system planning model to co-optimize investment and operations of generation, storage, and transmission facilities out to 2050. Our results show that, under business-as-usual conditions, wind and solar contribute more than half of new generation capacity by 2050, though this requires substantial expansion of natural gas-based capacity. While new hydropower appears to be less cost-competitive, the existing high capacity of hydropower provides critically important flexibility to integrate the wind and solar and to avoid further reliance on more expensive or polluting resources (e.g., natural gas). Over 90% emission cut by 2050 could be facilitated mostly by enhanced integration (predominantly after 2040) of wind, solar, and battery storage with 11%–28% additional cost, whereas enhanced expansion of hydropower reduces the cost of low-carbon transition, suggesting trade-off opportunities between saving costs and environment in selecting the clean energy resources. Achieving high emission reduction goals will also require enhanced sub-regional electricity trade, which could be mostly facilitated by existing interconnection capacities.

Strategic planning for sustainable electric system operations: Integrating renewables and energy storage

This work proposes a mathematical programming approach for strategic planning in power system operations with the aim of promoting a sustainable energy transition. The approach identifies optimal operating policies that integrate conventional generation plants and renewable energies to meet user demand while considering energy generation, transmission, and distribution. Additionally, the formulation determines the optimal storage units required in the energy transmission network to improve system stability and reduce operating costs by balancing energy supply and demand. However, the operation of the power system is limited by several factors, such as economic and environmental factors as well as energy losses. Therefore, the purpose is to operate the electricity system with the lowest operating cost while minimizing CO2 emissions generated by electricity production. Since there is a conflict between these objectives, a multi-objective approach is necessary to propose a compromise solution. The compromise solution represents a balance between technical, economic, and environmental factors; the results demonstrate that it is possible to achieve a balance between these factors. Finally, we present a case study of the Mexican Electricity System (SEN) to apply the developed model. The case study includes a maximum load operation analysis to determine the system’s limits and ranges. This analysis will enable system expansion or improvement planning to meet future energy demands.

Feasibility of innovative topography-based hybrid renewable electrical power system: A case study

Recently, climate change has attracted significant intension globally. Accordingly, numerous initiatives are under action for reducing the consumption of fossil fuels and increasing the share of renewable energy sources. This research work proposes an eco-friendly and sustainable electrical power system that could fully or partially fulfill requirements of the local load of the system under concern. The proposed power has the merit of utilizing topography of the site under concern, Al- Jabal Al-Gharbi district, Libya, to exploit the locally available resources such as biomass and sewage plants. The availability of resources was first studied, concluding that 110.87 × 106 m3⁄year are available for generating biogas and electricity. Moreover, biogas is extracted from biomass fermentation plants with a capacity of 244,845 tons/year produced from agricultural, municipality organic, livestock, and sewage residues in the proposed system. The feasibility of the proposed system is validated via a comprehensive economic and environmental comparison of different types of fuels. Furthermore, a mathematical model is developed for the Environmental Damage Cost (EDC) of CO2 emission for three scenarios: 1) disposing wastes, 2) firing fuel plus disposing of wastes, and 3) firing fuel plus biogas. The proposed system would save about 57% and 86% of CO2 from diesel and natural gas-fired power stations. Moreover, the Levelized Cost of Electricity (LCOE) generated from the proposed system is about 3.5 ¢⁄kWh, which is much lower than the actual cost of electricity generation in Libya (12 ¢/kWh). The annual savings of EDC due to CO2 is $6,968,613. This study could act as a pivot for implementing eco-friendly and sustainable energy source projects in the site under concern and/or similar sites.

Analysis of Experimental Data from Household Off-Grid System in Latvia

Abstract Autonomous off-grid systems might be seen as a favourable option when it comes to high grid connection fees and for a sustainable electric system in transition to a low-carbon, renewable-based decentralized system. To ensure such a system, accurate analysis of different scenarios is required to determine the optimal energy source mix and sizing of the off-grid system. Software computing techniques or mathematical models can help solve this task, but, unfortunately, it is unpredictable how actually such systems will perform in real life. There are not so many publications, where the real data and off-grid systems are analysed and compared to simulation results. Thus, this paper examines an experimental stand-alone electrical off-grid solution in Latvia. The operational data of real autonomous off-grid system are obtained for the off-grid system performance and control strategy analysis, which is highly relevant for the planning and dimensioning of affordable renewable off-grid systems.

Grid-Following Inverter-Based Resource: Numerical State–Space Modeling

In the pursuit of a sustainable electric power system, the integration of renewable energy sources and distributed energy resources is gradually replacing traditional power generation. These new resources are integrated into the grid via inverters, which, despite their efficient performance, present dynamic challenges to the power grid when implemented on a large scale. To maintain grid stability and ensure effective regulation during abnormal operations, various modeling techniques are necessary; while the dynamics of inverter-based resources (IBRs) are traditionally modeled by transfer functions, this paper sheds light on differential-algebraic equations (DAEs) modeling and numerical integration methods. The inherent limitations of transfer function modeling stem from its restricted applicability, as it is exclusively suitable for linear and time-invariant systems. In contrast, the nonlinear DAEs of the IBR system can be converted into a state–space form, which offers a versatile framework for modeling, evaluating, and designing a diverse array of systems. In addition to being compatible with time-varying systems and multiple-input multiple-output systems, the state–space technique may incorporate saturation and dead zone characteristics into the dynamic model. Our research focuses on IBR modeling in a grid-following scheme, which is current-controlled and synchronized to the grid by a phase-locked loop (PLL). The presented state–space model consists of the inverter, grid, control, and designed PLL. Beyond the discussion of its application to IBRs, the presented method holds the potential to solve a wide range of DAEs. The proposed model is compared with a benchmarked system.

Decarbonised Future Regional Airport Infrastructure

Sustainability and, especially, emission reductions are significant challenges for airports currently being addressed. The Clean Sky 2 project GENESIS addresses the environmental sustainability of hybrid-electric 50-passenger aircraft systems in a life cycle perspective to support the development of a technology roadmap for the transition to sustainable and competitive electric aircraft systems. This article originates from the GENESIS research and describes various options for ground power supply at a regional airport. Potential solutions for airport infrastructure with a short (2030), medium (2040) and long (2050) time horizon are proposed. This analysis includes estimating the future energy demand per day, month and year. In addition, the current flight plan based on conventional aircraft is adapted to the needs of a 50-PAX regional aircraft. Thus, this article provides an overview of the energy demand of a regional airport, divided into individual time horizons.

Faulty Branch Identification Method for DC Generation and Storage Systems With Multiple Series-Parallel Cells

Solar photovoltaic energy and electrochemical energy storage are key elements for the development of more sustainable and efficient electrical energy systems such as electric vehicles or microgrids. These systems require of multiple series-parallel cell connections that complicate enormously the location of possible ground faults. In this context, this article proposes a new method based on a low frequency periodical commutation of a grounding resistor placed in the midpoint of the DC source, that allows to discern the faulty branch by measuring the current at strategical positions of each string. The highest relative current variation when the system is grounded or ungrounded determines the faulty branch. The proposed method has been analyzed for three types of grounding connections by means of simulations and experimental tests using batteries, achieving successful results.

Design Exploration for Sustainable Regional Hybrid-Electric Aircraft: A Study Based on Technology Forecasts

The environmental impact of aviation in terms of noise and pollutant emissions has gained public attention in the last few years. In addition, the foreseen financial benefits of an increased energy efficiency have motivated the transport industry to invest in propulsion alternatives. This work is collocated within the Clean Sky 2 project GENESIS, focused on the environmental sustainability of 50-passenger hybrid-electric aircraft from a life-cycle-based perspective to support the development of a technology roadmap for transitioning towards sustainable and competitive electric aircraft systems. While several studies have already focused on the definition of possible aircraft designs combining several propulsion systems, the novelty of the present work is to consider technology forecasts and more comprehensive indicators in the design phase. These include the performance and emissions on a 200 nmi typical mission, which reflects the most economically attractive range for aircraft in the regional class. The work proposes a complete exploration of three major technology streams for energy storage: batteries, fuel cells, and turbine internal combustion engine generators, also including possible combinations of those technologies. The exploration was carried out through the execution of several designs of experiments aiming at the identification of the most promising solutions in terms of aircraft configuration for three different time horizons: short-term, 2025–2035; medium-term, 2035–2045; and long-term, 2045–2050+. As a result, in the short-term scenario, fuel energy consumption is estimated to be reduced by around 24% with respect to conventional aircraft with the same entry-into-service year thanks to the use of hybrid propulsive systems with lithium batteries. Fuel saving increases to 45% in the medium-term horizon due to the improvement in the energy density of storage systems. By the year 2050, when hydrogen fuel cells are estimated to be mature enough to completely replace kerosene-based engines, the forthcoming hybrid-electric aircraft promise no NOx and CO2 direct emissions, while being approximately 50% heavier than conventional ones.

Preface

The 8th International Symposium on Hydrogen Energy, Renewable Energy and Materials 2022 (HEREM2022) was successfully held on October 14-15, 2022 in Bangkok, Thailand Virtually using ZOOM due to the COVID-19 pandemic. The key topics of the HEREM2022 include Hydrogen Energy, Renewable Energy, Electric Power Systems, Energy Efficiency, Energy Materials Science and Electro-Chemical Engineering, etc. The HEREM2022 dedicates itself to providing networking possibilities for researchers, scientists, engineers and scholars to share their experience, amazing ideas and innovative research in the field of Energy Materials and Engineering.The select proceeding of HEREM2022 to be published as a volume in the Journal of Physics: Conference Series (doi: 10.1088/issn.1742-6596, e-ISSN: 1742-6596, Print ISSN: 1742-6588). This volume is having archival value with interesting research findings in area of hydrogen and renewable energy technologies for contributing in clean energy transition. The HEREM2022 select proceeding of HEREM2022 has highlighted and discussed the critical need of hydrogen energy technologies, electro-chemical energy conversion systems, sustainable electrical energy systems for contributing in achieving UN’s Sustainable Development Goal 7.The organizing and editorial committee of HEREM2022 sincerely appreciate the authors for disseminating research findings of sustainable energy systems as well as to the technical reviewers for providing the comments in improving the technical quality of the selected manuscripts. On behalf of the HEREM2022 organizing committee, I would like to congratulate authors of the published papers for disseminating the research findings at HEREM2022, and very much thankful to the speakers for presenting and sharing their knowledge with the participants.List of Committee Member is available in this pdf.

A novel discrete GM(2,1) model with a polynomial term for forecasting electricity consumption

• A novel discrete GM(2,1) model with a polynomial term is proposed. • The generalization and adaptability of the proposed model were validated from the theoretical and practical perspectives. • The newly-designed model is applied to predict per capita living electricity consumption. The forecast of electrical energy demand has played an increasingly relevant role in sustainable electrical power system. This paper develops a new method for forecasting China's per capita living electricity consumption by grey modelling technique. Considering the multiple and mixed change patterns, a novel discrete grey model with polynomial term (abbreviated as DGM(2,1, k n )) is proposed in this study. Firstly, the polynomial term is introduced into the discrete DGM(2,1) model. Secondly, the Tikhonov regularization method is employed to solve the overfitting problem. Lastly, two published cases and China's per capita living electricity consumption are used to validate the generalization and adaptability of the newly-designed model. The numerical results of such experiments show that the proposed model outperforms other competitive models in terms of accuracy level. Therefore, the projections of China's per capita living electricity consumption in 2020 and 2025 have been made for providing a solid reference for the formulation of electrical power strategies.

Optimal designing of PV-diesel generator-based system using HOMER software

Coal, petroleum, natural gas, and other fossil fuels are examples of conventional energy resources. They are not supplied at the pace at which they are spent, which implies that once used, they are not regenerated again, and generation takes millions of years. Because of rising load and demand, it has become necessary to transition from conventional to renewable energy supplies. Development of sustainable electricity systems is also a critical prerequisite for the country's financial prosperity. This article investigates the feasibility of PV and diesel generator-based system that is appropriate for the Akhnoor town in Jammu district of Jammu and Kashmir in India using HOMER Software.According to the optimization results the ideal solution is to use components having NPC of $16,157. PV arrays used are of 1.98 kW and 1.40 kW generator is required for the proposed system. The proposed system has the levelized COE of $0.4280 and an OC of $493.72. Out of 880 solutions simulated, 680 were feasible. The proposed system consists of Silicon Nanoparticles Enhance Solar Cells due to its high efficiency.

A green energy circular system with carbon capturing and waste minimization in a smart grid power management

Sustainable electricity production is an energy-efficient strategy aimed at both economic progress and environmental conservation. The power generation sector is the major contributor to global emissions and waste. The scope of circular economy in the power production sector with investments in waste minimization and emission reduction was not discussed in previous studies. In this context, a circular sustainable smart electric supply chain system is introduced in this paper with an aim of maximizing the profit with the minimum amount of emissions and waste generated from the power generation units. The power plant in this system consists of four power generation units that generate electricity from coal, waste, wind, and solar plants. A smart grid management system is used in this system for an efficient power supply according to the demands of the customer, and it enhances the system to distribute the power from renewable energies. In this system, the carbon dioxide from the thermal plants is captured and converted to natural gas to reduce emissions. Municipal and industrial waste is transformed into composite fuel to generate electricity. The profit for each unit and the customer’s demand for electricity depends on the circularity index. Linear demand versus linear and logistical cases of unit profit was considered. This study theoretically and numerically maximizes the profit of the system with optimal power consumption, circularity index of electricity, and green and waste minimization investment as per the carbon cap policy. To find the optimal strategies for maximum profit, an algorithm was developed. Sensitivity analysis is done to determine the fluctuations in the profit, emission cost, waste cost, circularity index, and power consumption due to the variations in parameters. The wise allocation of power generation from each unit and reduce energy loss by installing efficient storage devices will result in a higher profit. A system with the high efficacy of green techniques to reduce emissions, a smart grid to minimize waste, higher taxes to regulate emissions, and a rise in the amount of production of electricity from renewable sources will result in a greener power system that gains more profit than conventional systems. The key findings state that electric supply chain systems can obtain a good profit in a more sustainable manner than conventional systems.

A Ground Fault Location Method for DC Systems Through Multiple Grounding Connections

Direct current (dc) systems have an increasingly important role in electrical systems, especially photovoltaic (PV) solar power plants and battery storage systems as they are essential for the development of more sustainable, efficient, and reliable electrical systems. PV panels and batteries are generally composed of multiple series-parallel cells. This fact makes their fault diagnosis challenging, especially against ground faults as these systems are generally ungrounded. In this article, a ground fault location method for dc sources with multiple series-parallel cells is proposed. It estimates the faulty branch, the faulty cell location inside this branch and its fault resistance. The method is based on the output current measurement of each branch and on the voltage measurement on a grounding resistor, which is switched between three positions: the positive, the midpoint and the negative terminals of the protected dc system. To validate it, several computer simulations and experimental tests on a battery pack have been carried out. The results obtained proves an excellent performance for faulty cell location and fault resistance estimation, although further investigations are required to better discern the faulty branch.