Electrical Energy Demand Research Articles

Power Grid Renovation: A Comprehensive Review of Technical Challenges and Innovations for Medium Voltage Cable Replacement

The rapid growth of electrical energy demands raises the need for the modernization of distribution grids. Medium-voltage (MV) aged cables are infrastructures facing significant challenges that can compromise the security of supply and reduce the reliability of power grids. To address the challenges, there is a growing interest in optimizing cable replacement and management strategies. This comprehensive review focuses on the technical challenges and innovations associated with MV cable replacement, highlighting defect detection, lifetime estimation, reliability assessment, and management strategies. Various methods for detecting and monitoring cable defects and discussing their advantages and limitations are surveyed. Moreover, different models and techniques for estimating the remaining useful life of MV cables are explored, emphasizing the importance of accurate predictions for assessing cable reliability and optimizing replacement schedules. Furthermore, emerging technologies that enhance cable management strategies are also highlighted. This review provides insights and recommendations for future research and development, paving the way for the sustainable evolution of power grids.

Energy Efficiency Analysis of the Implementation of On-Grid Solar Power System at Pertamina Labuhan Deli Fuel Depot

Economic growth and the increasing demand for electrical energy require a breakthrough in the provision of electrical energy, one of which is the use of renewable and environmentally friendly energy. Solar energy is one of the renewable energies that can be used as a solar PV system. This solar PV system can also be combined with the PLN network (grid) and generators to meet electrical energy needs. This study aims to find out the amount of electrical energy efficiency value that can be produced by the plant every month, and whether it can affect the electricity bill paid by PT Pertamina Patra Niaga every month. Methods This research uses observation methods and collects various data related to the installation of Solar Power Plants on the Grid starting from April to September 2024. This research contains the results of the total electrical energy produced by the solar power plant, the efficiency of the solar power plant as well as the saving costs generated after the installation of the solar power plant at the Pertamina Labuhan Deli Fuel Depot.

Optimal Placement of TCSC and DPFC on Nigeria Power Transmission Network for Capacity Enhancement

The increasing demand for electrical energy and the high costs and challenges associated with building new transmission lines highlight the need to optimize existing power transmission networks. This study focuses on optimizing or enhancing Nigeria's 28-bus power transmission system using Flexible Alternating Current Transmission System (FACTS) devices, specifically, Dynamic Power Flow Controller (DPFC) and Thyristor-Controlled Series Compensator (TCSC). This research employed the Bacterial Foraging Optimization Algorithm (BFOA) in MATLAB to determine the optimal placement and sizing of DPFC and TCSC to minimize power losses, voltage deviations, and installation costs. Simulation results were compared, before and after incorporating the FACTS devices. In the base case, 32% of the buses had voltage profiles outside the acceptable range (0.95 to 1.05 p.u.), with real power loss of 602.91 kW and reactive power loss of 4559.69 kVAR. After optimally placing two DPFC and two TCSC devices in the system, all bus voltages were regulated to fall between 0.95 and 1.06 p.u., while real and reactive power losses were reduced by approximately 84.6% and 84.7%, respectively. This demonstrates a significant improvement in the efficiency and capacity of the power transmission network.

Research on the status and prospect of microgrid technology

Abstract. With the increasing demand for electrical energy and the appeal of environmental protection, the world has started to pay attention to the application of microgrids. A microgrid is a grid with many advantages, such as independence, effectiveness in working, and environmental friendliness, and can solve both energy and environmental problems. The paper reviews the microgrid system: how it functions, how it has advantages in energy and environmental aspects, and the prospects of microgrid in the future using a literature review. Microgrid has a flexible operation since it can find the optimum solution for generation, transmission, and distribution by shifting smoothly between island mode (which generates electricity by itself and directly transmits it to the supply side) and grid-connected mode (which connects to macrogrid and is dependent on its power supply). It also has energy reliability for its control system and energy storage system to coordinate the output power, which enhances the utility of energy resources. Microgrid has great potential for solving energy problems in remote or poverty-stricken areas and has unlimited prospects in industry, residential communities, and utilities and energy providers.

Process Simulation and Technical Evaluation Using Water-Energy-Product (WEP) Analysis of an Extractive-Based Biorefinery of Creole-Antillean Avocado Produced in the Montes De María

The annual increase in the world’s population significantly contributes to recent climate change and variability. Therefore, researchers, engineers, and professionals in all fields must integrate sustainability criteria into their decision-making. These criteria aim to minimize the environmental, social, economic, and energy impacts of human activities and industrial processes, helping mitigate climate change. This research focuses on developing scalable technology for the comprehensive use of avocados, adhering to sustainability principles. This work presents the modeling, simulation, and the WEP (Water-Energy-Product) technical evaluation of the process for obtaining bio-oil, chlorophyll, and biopesticide from the Creole-Antillean avocado. For this, the extractive-based biorefinery data related to water, energy, and products are taken from the material balance based on experimental results and process simulation. Then, eight process parameters are calculated, and eleven technical indicators are determined. Later, the extreme technical limitations for every indicator are demarcated, and an evaluation of the performance of the indicators is carried out. Results showed that the process has a high execution in aspects such as fractional water cost (TCF) and energy cost (TCE), as well as solvent reuse during extraction processes (SRI) and production yield, noting that the mentioned indicators are above 80%. In contrast, the metrics related to water management (FWC) and specific energy (ESI) showed the lowest performance. These discoveries support the use of optimization techniques like mass process integration. The energy-related indicators reveal that the process presents both benefits and drawbacks. One of the drawbacks is the energy source due to the high demand for electrical energy in the process, compared to natural gas. The specific energy intensity indicator (ESI) showed an intermediate performance (74%), indicating that the process consumes high energy. This indicator enables us to highlight that we can find energy aspects that require further study; for this reason, it is suitable to say that there is potential to enhance the energy efficiency of the process by applying energy integration methods.

Mitigating the charging rush hour

Great effort is put into making our mobility system more sustainable in order to mitigate climate change. One corner stone of this endeavour is the transition from internal combustion engines to electric engines for private cars. This transition, however, introduces new challenges, especially regarding the demand for electrical energy from renewable sources. One emerging phenomenon is the so-called charging rush hour, i.e. a sharp demand spike when many people arrive home and begin charging their electric cars. In this study we use an agent-based model calibrated with empirical data on mobility behaviour to investigate strategies for mitigating this charging rush hour. Studied counter strategies include telecommuting and the possibility to charge the car at work. Our findings show that the baseline peak of 65 MW per 100 000 people can only be reduced to 55 MW per 100 000 people even when combining multiple strategies. Thus the small incentives and policy changes investigated here are not enough to solve the problem of the charging rush hour and more disruptive changes to our mobility system are required.

Piecewise-linear MILP optimization for energy system design onboard hybrid ships

Abstract In recent decades the share of GHG (Green House Gases) such as carbon dioxide (CO2), and local pollutants as carbon monoxide (CO), nitrogen oxides (NOx), and sulphur oxides (SOx) produced by shipping has significantly increased. In the case of CO2, the IMO (International Maritime Organization) has estimated that emissions will increase by a range of 90-130% in 2050 as compared to 2008. In this scope, penetration of new technologies such as Battery Energy Storage Systems (BES) can reduce the share of emissions, giving more flexibility to the ship’s system. In this work, an optimization algorithm based on Mixed-Integer-Linear-Programming (MILP) approach has been developed to define the best environmentally sustainable technology mix to be installed on board. The model is based on Demand-Driven optimization, where the main goal is to satisfy electrical and thermal energy demand, which is achieved by using linear constraints. The objective function is defined to minimize on-board energy production costs considering the CAPEX and OPEX of each technology, choosing the best technology mix and giving the schedule of working conditions for each installed technology. The non linearity of the components’ characteristic curves is tackled through piecewise-linearization approach. In this way, the algorithm can optimize the real operating conditions for technologies with higher accuracy of partial load conditions. The case study is based on real energy demand profiles of a cruise ship sailing between Stockholm and the island of Åland, in the Baltic Sea.

Carbon-Nickel Oxide Nanofiber based Supercapacitors for Improvement of Electrochemical Performance

Now a days, demand for electrical energy is increasing because most of our gadgets and devices based on electricity. Due to the depletion of fossil fuel much more attention is given to renewable energy sources and devices to store that energy. Between these energy storage devices electrochemical energy storage devices has got more attention and among electrochemical energy storage devices, batteries are dominant, but they experience some safety issue, slow charge transfer and cannot meet high power requirement for numerous applications. Thus, as compare to batteries supercapacitor have high power density and fast charge transfer. So much more attention is going on to increase the performance of supercapacitors. In this study, hydrothermal method is used to synthesis rGO/NiO composite and electrospinning to fabricate rGO/NiO composite nanofibers. Scanning electron microscopy (SEM) and x-ray diffraction (XRD) is performed to study morphological and structural properties. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) are performed to study the electrochemical behavior. Reduced graphene oxide shows specific capacitance as low as 91.6 F/g. NiO nanostructures, rGO/NiO composite and rGO/NiO composite nanofibers shows specific capacitance of 256.4 F/g, 537.8 F/g and 663.8 F/g respectively.

Analysis of The Impact of Temperature and Discharge Current on The Efficiency of LiFePO4 Batteries in Solar Charging Stations

The demand for electrical energy is increasing, along with technological advancements and population growth. Many countries still rely on petroleum, coal, and aerosol gasoline, exacerbating global warming. Electric vehicles offer a promising solution to reduce greenhouse gas emissions and dependence on fossil fuels, although their primary challenge is the availability of charging infrastructure. Solar-powered electric motor charging stations can help reduce electricity demand and global warming. An efficient charging system is needed to analyse the impact of temperature and discharge current on the energy produced to achieve this. Several load tests and temperature measurements over 5 days were conducted to cluster temperatures occurring throughout a full day. The tests using data acquisition showed energy losses caused by the effect of temperature on the charging station's storage battery. Energy efficiency graphs for each test case indicated a varied decrease in energy efficiency, with higher efficiency at lower temperatures and smaller energy losses compared to other temperatures. The load amount also affects the magnitude of energy losses. At a 500W load, the average energy loss was 46Wh, while at a 1000W load, the average energy loss was 52Wh per hour of testing the storage battery discharge. In summary, temperature and load amount can affect energy efficiency and the resulting losses.

Analysis of the Electric Power Distribution System Service Reliability Index at PLN Lancang Garam

The level of electrical energy demand in an area reflects the welfare of that community. The greater the use of electrical energy, the higher the community's standard of living, followed by the public's critical attitude towards everything that happens and influences lives, including electricity services. Generally, a network's reliability level can be seen from the size of the SAIDI and SAIFI values on the PLN (state electricity company) side. The calculation and reliability analysis results of the Lhokseumawe ULP above show that the total SAIFI index value is 2.68 times/year. The SAIFI Rayon Lhokseumawe reliability index is categorized as reliable because its value does not exceed the standard set by PLN in SPLN 68-2 of 1986, namely 3.2 times/year. The total value of the SAIDI index is 45.30 hours/year. The Lhokseumawe Rayon SAIDI reliability index is categorized as unreliable because its value exceeds the standard set by PLN in SPLN 68-2 of 1986, namely 21 hours/year. There are certainly differences in infrastructure, electrical equipment, and number of customers in 1986 compared to current years; this has a different influence on electricity reliability values such as SAIDI and SAIFI.

GAPS OF INDIAN ELECTRICAL ENERGY SECTOR AND ITS OPTIMAL MITIGATION BY USING OPTIMAL UTILIZATION OF INDIAN RENEWABLE ENERGY POLICY WITH THE HELP OF THE P&O MPPT TECHNIQUE

Developing countries, especially, India, depend importantly on energy sources to perform their country’s industrial and economic activities. Mainly the two factors continuous population growth of the country and the rapid growth rate of industrialization of the country, the gap between electrical energy supply and demand for electrical energy is slowly and consistently increasing. To resolve this unevenness, there is a jointly planned attempt is required to enhance the contribution of renewable energy in the all over mix of energy. Despite these attempts, unexpected surges caused by the sector of domestic energy consumption could lead to important shortfalls between energy requirements at peak demand and available supply in India. As a solution to this challenge, the Union government of India has launched a new policy, named PM SURYA GHAR: MUFT BIJLI YOJANA, targeted to handle this crucial problem head-on. This initiative requires addressing the increasing energy demand by promoting the utilization of solar power in households throughout the length and breadth of the country. With the implementation techniques of Photo voltaic optimization, this analysis explores how such types of strategies can play a significant role in filling the gap between the energy supply-demand in the Indian context. Employing the solar energy potential and optimizing and utilization of solar energy, creates a path to not only meet the enhancing energy requirements but also creates the path for a more environmentally friendly and sustainable energy in India. By integration of innovative technologies and solutions of renewable energy holds the key to ensuring a balanced, sustainable, stable energy supply for the future of India and country’s growth and development.

A tri-level hybrid stochastic-IGDT dynamic planning model for resilience enhancement of community-integrated energy systems

In this paper, a resilience-oriented dynamic planning framework is developed for optimal sizing of the community-integrated energy system components, including photovoltaic system, wind turbine, boiler, power to gas technology, combined heat and power, and storage devices. The proposed framework is formulated as a tri-level linear programming that performs Community-Integrated Energy Systems design under normal conditions at the first level while evaluating system operation during disastrous conditions at the second level. In the third level, re-planning is done based on information-gap decision theory to enhance community-integrated energy systems’ resilience against various natural disasters. Stochastic programming is also employed at all levels to address the uncertainty of electricity market price, energy demand, solar radiation, and wind speed. A detailed P2G system including, a methanation device, electrolysis, and hydrogen storage is designed to improve the resilience of the system. In addition, the power to gas proposed in this model is coupled with a carbon capture unit to mitigate carbon emission by reusing emitted carbon from the flue gas of the boiler and combined heat and power. Various economic metrics and technical constraints are also considered to achieve a realistic design. Numerical simulation results demonstrate that the positive interplay of renewable energy resources and energy storage technologies, specifically P2G, assisted the CIES in maintaining a stable and uninterrupted energy supply during extreme events. The results exhibit that increasing only 10 % of the resilience budget can decrease >93 % of unserved demand and helps reduction of >37 % of carbon emissions.

Karakteristik Breakdown Voltage Pada Dielektrik Minyak Mineral dan Minyak Ester Natural

The increasing demand for electrical energy, driven by population growth and industrial development, necessitates efficient and sustainable power distribution systems. Transformers, essential components of these systems, typically use mineral oil for insulation and cooling, despite its environmental drawbacks, such as high carbon emissions and non-biodegradability. In response, natural ester oils have emerged as eco-friendly alternatives. This study aimed to compare the dielectric breakdown voltage characteristics of mineral oil (Diala B) and natural ester oil (FR3) in transformer applications. The testing followed the IEC 60156 standard, focusing on transformers operating at 20 kV, with a minimum breakdown voltage threshold of 30 kV/2.5mm. Both treated and untreated samples were examined.The results indicated that FR3 ester oil exhibited superior dielectric properties, including higher breakdown voltage, flashpoint, and firepoint, as well as lower carbon emissions compared to mineral oil. These findings suggest that natural ester oil has significant potential as a sustainable replacement for mineral oil, particularly in applications where environmental and safety concerns are prioritized.The study recommends further long-term testing under operational conditions to confirm the performance and stability of ester oil in real-world transformer applications. These findings contribute to the growing body of research supporting the transition to more environmentally friendly transformer insulation materials, which could have broad implications for the power industry’s sustainability efforts

Analyzing the influence of electric vehicle charging scheduling on distribution transformer lifespan

The ongoing growth in global electricity demand and rapid proliferation of electric vehicles (EVs) are posing challenges to the operation of the low voltage power networks and their components. This study aims to analyze the impacts of peak-load demand on the distribution transformers, considering mild and extreme combinations of electric energy demand and localized charging of plug-in EVs under their different penetration levels, hypothesizing that shifting the demand for charging throughout the day can reduce the aging of distribution transformers. The proposed method employs a fuzzy-logic-based tool, which incorporates the influence of ambient temperature, higher harmonics, reactive power compensation, reverse power flows, and overload. Three different charging/discharging modes have been considered: demand charging, off-peak charging, and synergy of off-peak charging and vehicle-to-house technology. The results indicate that off-peak charging emerges as 2.1 times more effective than demand charging in terms of the transformer's loss of life, particularly for ultimate EV penetration of 100 %. It is demonstrated that the utilization of charging scheduling for EVs should be prioritized to defer costly system upgrades and reinforcements, particularly when EV penetration exceeds 50 %.

Enhancing energy control for a hybrid system comprising a wind turbine, diesel generator, and storage systems

The increase in demand for electrical energy has made renewable energy sources, such as wind power, increasingly attractive. However, intermittency and variability represent the major problems of these types of energies. The hybridization of several energy sources allows to have a reliable and efficient supply system. This paper was interested in the control of a hybrid energy system, which includes a wind turbine, storage systems (batteries and super-capacitors) and a conventional diesel generator, with the aim of generating constant power. A control strategy is developed taking into account the various constraints of the hybrid system. Both of storage systems as well as the diesel generator operate according to the modes presented in the supervision algorithm to absorb and compensate the fluctuation of the wind energy and reach to a constant energy flow. The super-capacitor operates before the battery to absorb the power peaks in both charge and discharge modes. The hybrid system is simulated using MATLAB/Simulink software, and the results are provided in order to show the effectiveness of this control strategy.

Implementing of a grid-connected PV energy system in building with medium consumption: A techno- economic case study

Renewable energy sources facilitate decentralized electricity production, reducing dependence on fossil fuels and contributing to a sustainable energy era. Algeria is one of the countries implementing a policy aimed at energy transition, with buildings playing a major role in this process. They consume more energy than any other sector and therefore significantly contribute to climate change. While various projects related to energy efficiency are being carried out, they are mostly limited to rural and Saharan areas or low-consumption residential buildings. The objective of this paper is to demonstrate the feasibility of integrating a grid-connected photovoltaic system into a medium-consumption building located in one of Algeria’s major cities, Constantine, to meet the building’s electrical energy demand. This paper presents a methodology for optimally sizing a grid-connected photovoltaic system to supply power to the Institute of Nutrition, Food, and Agro-Food Technologies (INATAA) in Constantine, Algeria. The technical and economic aspects of the system’s components were considered to determine the most feasible configuration, using real data from the institute and the HOMER Pro simulation software. The simulation results show that the grid-connected PV system, without storage, can meet the institute’s energy demand (with 671,061 kWh/year of energy produced, of which 81.3 % is photovoltaic energy). This configuration offers the lowest costs, with a Net Present Cost (NPC) of $748,413 and a Cost of Energy (COE) of $0.0894/kWh. Therefore, integration of a grid-connected photovoltaic system in medium-consumption buildings can effectively meet energy needs while reducing costs. Thus, this study demonstrates the technical and economic feasibility of such system to support the energy transition in urban areas in Algeria.

Techno-economic of Residential Application for Grid-Connected Photovoltaic-Battery under Net Energy Metering

Nowadays, the demand for electrical energy is increasing due to the application of electrical equipment such as air conditioning, refrigerators, television, computers etc. Grid-connected photovoltaic is a network that allows for significant penetration of electricity by PV generation into the national utility grid under Net Energy Metering (NEM) incentive. Under NEM incentive, the owner can offset the energy for 10 years to reduce the electricity billing. Unfortunately, after that, the self-consumption (SELCO) program is implemented. Under SELCO program, the energy generated by PV will be consumed by the owner and there is no rebate for excess energy to the grid. This paper represents the techno-economic analysis of different rated power of PV design installed for residential applications. The 1.04kWp, 1.56kWp and 2.08kWp PV are designed to charge 5.544kWh battery and simulated by using PVsyst software. The payback period is calculated under Net Energy Metering (NEM) 3.0 incentive. As a result, 1.56kWp is the optimize sizing for grid-connected PV-battery with electricity billing saving at RM730.20 per year under one-on-one program and RM660.61 under SELCO program. Thus, return on investment (ROI) of this system design is 16.5 years.

Transient stability enhancement of Beles to Bahir Dar transmission line using adaptive neuro-fuzzy-based unified power flow controller

A power system is a complex, nonlinear, and dynamic system, with operating parameters that change over time. Because of the complexity of big load lines and faults, high-voltage transmission power systems are usually vulnerable to transient instability concerns, resulting in power losses and increased voltage variation. This issue has the potential to cause catastrophic events such as cascade failure or widespread blackouts. This problem affects Ethiopia's high-voltage transmission power grid in the northwest area. Because of the increased demand for electrical energy, transmission lines' maximum carrying capacity should be enhanced to maintain a secure and uninterrupted power supply to consumers. To address the problem, ANFIS-based UPFC is used for high-voltage transmission lines. This device was chosen as the ideal alternative due to its capacity to rapidly correct reactive power on high-voltage transmission networks. The PSO algorithm was used to determine the best location for the UPFC. The ANFIS controller receives voltage error and rate of change of voltage error as inputs. Seventy percentage of the retrieved data are used for ANFIS training and 30% for ANFIS testing. To show the performance of the proposed controller, three-phase ground faults are used from a severity perspective. When a three-phase ground fault occurs at the midpoint of the Beles to Bahir Dar transmission line, for instance, the settling time of rotor angle deviation, rotor speed, rotor speed deviation, and output active power of synchronous generators using ANFIS-based UPFC is reduced by 70.58%, 37.75%, 37.75%, and 43.75%, respectively, compared to a system without UPFC. At peak load, PI-based UPFC and ANFIS-based UPFC reduce active power loss by 51.25% and 71.50%, respectively, compared to a system without UPFC on the Beles to Bahir Dar transmission line. In terms of percentage overshoot and settling time, ANFIS-based UPFC outperforms PI-based UPFC for transient stability enhancement.

Performance of Permanent Magnet Synchronous Generator (pmsg) 3 Phase Radial Flux Results Modification of Induction Motor

Abstract: The demand for electrical energy in Indonesia has experienced a significant surge, becoming indispensable for nearly all modern activities. However, despite this surge, the primary energy source for power plants continues to heavily rely on fossil fuels. Consequently, it is imperative to transition towards renewable energy sources to mitigate environmental impact and tackle the prevailing energy crisis. In response to this need, permanent magnet synchronous generators have emerged as a promising alternative within the electricity industry. These generators operate by utilizing permanent magnets to generate a magnetic field within the coil, thereby eliminating the necessity for excitation current. By leveraging renewable energy sources such as wind or hydro power, these generators strive to optimize electricity production and alleviate the ongoing energy crisis. This research project aims to repurpose materials sourced from used water pump motors, including rotors and stators, to construct permanent magnet synchronous generators. The process involves incorporating permanent magnets into the rotor and modifying the original motor winding. Through rigorous testing involving the application of a 40 Ohm load and varying rotational speeds between 2000 and 1600 rpm, the research reveals that the generator can generate a minimum power output of 0.7 Watts at 200 rpm and a maximum power output of 41.8 Watts at 1600 rpm. The optimal efficiency of 75.78% is attained at 400 rpm. Overall, this research underscores the potential of repurposing existing materials to develop renewable energy solutions, offering a sustainable approach to addressing not only the energy needs of Indonesia but also those of other regions globally.

Reactive Power Compensation for Standalone Hybrid Power System Using Facts Devices

Reactive power compensation is essential in hybrid grid-connected systems because power electronic inverters utilized for supplying DC energy into the grid causes a reduction in the overall power factor of the power systems. Due to the ability to provide a reliable and efficient power supply to remote and off-grid areas, hybrid power systems are growing in popularity. It can provide greater opportunities for operational growth by combining economic and technology advancement. To meet the demand for electrical energy in both regular and critical situations, operators must be in charge of the power systems reliable and secure operation. The primary objective of the work is to control the reactive power flow in a grid-connected hybrid renewable energy system (PV-wind-battery). The power quality problems that these systems frequently experience include voltage sags, harmonics, and flicker. A FACTS device Unified Power Quality controller (UPQC) with a Genetic Algorithm based PI controller is suggested to handle these power quality issues. In order to improve the performance of the power system, the proposed optimization approaches are used to tune the UPQC in a multiline transmission system. The model was developed with the help of the MATLAB/Simulink work framework.