Electric Power Usage Research Articles

Optimisation of LED luminaires renewal interval based on proposed CLO adjustment method

A considerable part of electrical power is consumed in lighting systems. Electrical power usage and, as a result, generation is proportional to CO2 emissions. CO2 emissions result in climate change. Many countries encouraged people to use modern light sources, including LEDs, to increase the efficiency of lighting systems. An LED, during its long life, is subjected to gradual degradation. Its degradation can be understood from its radiant flux decrement. Some standards, including LM 80-08, addressed this issue. Constant lumen output (CLO) drivers are used to deal with LED degradation issues. There is not much scientific research on the topic of CLO. This paper suggests a scientific approach to finding CLO's exact output voltage as a function of time during the LED lifetime, limiting energy consumption to the required value. Also, a method for finding the best time to replace LED luminaires to minimise the financial burden for the owners has been found. By optimising renewal time for LED luminaires, energy usage (CO2 emission) and end-of-life waste will be managed to the required value. In addition, for use in CLOs, the paper suggests adding more specified data to the LM 80-08 report.

Broadband and high-efficiency acoustic energy harvesting with loudspeaker enhanced by sonic black hole

It is well-known that acoustic energy sources can be seen as a promising alternative energy resource by using acoustic energy harvester (AEH) which can transform sound energy into usable electrical power. However, the current AEHs have been restricted by their narrow bandwidths and low energy conversion efficiencies. In this study, a broadband and high efficient AEH is presented. The proposed AEH comprises an open-end sonic black hole (SBH) structure and an electrodynamic loudspeaker. The sound pressure is amplified through the open-end SBH structure, then the loudspeaker is used as electricity generator to convert acoustic energy into electric energy. The open-end SBH is a cylindrical tube with an array of regularly-spaced rigid-walled thin rings. The inner radii of the SBH rings are quadratically decreasing and the SBH effect can be obtained. The model for energy harvesting and sound absorption performance of the proposed AEH is then presented. Finally, the open-end SBH is fabricated by 3D printing apparatus. A prototype of the AEH is designed and tested by using an impedance tube. The energy conversion efficiency and absorption coefficient from calculation and experiment show a reasonable agreement. The proposed AEH can convert 11 % of total incident sound energy from 50 Hz to 800 Hz. The maximum energy conversion efficiency can achieve 65 % at 425 Hz under optimal resistance load. Furthermore, the broadband sound absorption can also be achieved by using the proposed AEH.

A stochastic averaging mathematical framework for design and optimization of nonlinear energy harvesters with several electrical DOFs

Energy harvesters for mechanical vibrations are electro-mechanical systems designed to capture ambient dispersed kinetic energy, and to convert it into usable electrical power. The random nature of mechanical vibrations, combined with the intrinsic non-linearity of the harvester, implies that long, time domain Monte-Carlo simulations are required to assess the device performance, making the analysis burdensome when a large parameter space must be explored. Therefore a simplified, albeit approximate, semi-analytical analysis technique is of paramount importance. In this work we present a methodology for the analysis and design of nonlinear piezoelectric energy harvesters for random mechanical vibrations. The methodology is based on the combined application of model order reduction, to project the dynamics onto a lower dimensional space, and of stochastic averaging, to calculate the stationary probability density function of the reduced variables. The probability distribution is used to calculate expectations of the most relevant quantities, like output voltage, harvested power and power efficiency. Based on our previous works, we consider an energy harvester with a matching network, interposed between the harvester and the load, that reduces the impedance mismatch between the two stages. The methodology is applied to the optimization of the matching network, allowing to maximize the global harvested power and the conversion efficiency. We show that the proposed methodology gives accurate predictions of the harvester’s performance, and that it can be used to significantly simplify the analysis, design and optimization of the device.

Optimizing plasma-activated water for enhanced microbial control in agricultural produce processing

The study utilized a pinhole plasma jet discharge system to generate plasma-activated water (PAW) for the removal of microbes on bird's eye chili. Optimal conditions for PAW generation were determined using response surface methodology, achieving maximum microbial inactivation. The novelty of this study lies in designing a PAW system model for agricultural cooperatives using the Quality Function Deployment (QFD) methodology, which integrates customer and engineer/designer perspectives. The results demonstrate a maximum 82.54% microbial removal rate on bird's eye chili under optimal conditions (e.g., exposure time = 20 min, Ar gas flow rate = 5 L/min, and O2 mixture = 2% Ar gas), indicating effective antimicrobial activity of plasma-activated water. Furthermore, a model of the PAW system for agricultural cooperatives, including cost and electrical power usage estimates, is proposed based on the correlation matrix of QFD. This conceptual PAW model for agricultural cooperatives warrants further investigation to assess its consistency in sterilization efficiency and long-term effects on treated agricultural products.

Lead-Free Double Perovskites Rb2TlSbX6 (X=Cl, Br, and I) As an Emerging Aspirant for Solar Cells and Green Energy Applications

This study utilized the WIEN2k simulation program to examine the structural, mechanical, thermodynamic, optoelectronic, and thermoelectric characteristics of lead-free double perovskites Rb2TlSbX6 (X=Cl, Br, and I). The objective is to assess their potential contribution to next-generation photovoltaic and thermoelectric systems. The ab initio molecular dynamics (AIMD) has validated that materials are thermodynamically stable. Examining mechanical features confirms the mechanical stability and ductile characteristics of studied perovskites. Rb2TlSbCl6 exhibits superior flexibility and stiffness, whereas Rb2TlSbI6 demonstrates the highest level of anisotropy. The thermodynamic parameters confirm the thermal stability and stronger bonding at elevated pressure and temperature. The electronic features, determined by implementing the GGA-PBE and TB-mBJ functionals, indicate direct band gaps at the Γ- Γ position. The band gap ranges from 1.22 eV to 1.74 eV, 0.94 to 1.34 eV, and 0.81 eV to 1.15 eV for Rb2TlSbCl6, Rb2TlSbBr6, and Rb2TlSbI6, respectively. The analyzed optical characteristics reveal significant absorption and conductivity with decreased reflectance and optical loss between 0 and 6 eV. Rb2TlSbI6 has the greatest dielectric constant, which suggests a lower recombination rate of electron-hole pairs. The thermoelectric characteristics demonstrate a large figure of merit values of 0.78, 0.80, and 0.84 at room temperature. Therefore, these materials have the significant capability forsolar cell technology and may effectively convert thermal energy into usable electrical power.

An adaptive methodology based on predictive deep learning and context aware clustering for electricity power usage mining and optimization at different granularity levels

Smart metering in electricity power grid is an optimistic trend at global level. All smart devices and appliances based on Internet of Things (IoT) are now playing very significant role in household. These days’ electric power usage mining and optimization is possible down to meter level only. However, it is very challenging and significant to go down to different granularity levels such as appliances, various sensors and activities etc. The shifting of the electric power usage to low price electricity is also significant and possible by mining and optimizing electric power usage behaviour at low level. All smart appliances and activities are needs to be customized to when you use them. This paper proposes an adaptive methodology based on predictive deep learning and context aware clustering to discover new ways for mining and optimization of electric power usage at different granularity levels and make optimal decisions for shifting electric power usage to low cost. Here we have considered households and business meters approximately 2000 with unique id of each meter. The data of three months is used for user preference of starting appliance. The predictive accuracy of proposed methodology for usage mining and optimization is improved by average 4 %. Different input data features are used to form clusters of meters with similar power consumption behaviour for household occupancy. The clustering accuracy for household occupancy is improved from 0.68 to 0.91. The impact of accurate household occupancy detection and appliance usage mining and optimization is in reduction of electric power cost. The consumer can see how electric power efficiency and time-of-use shift makes a difference using experimental setup.

Research on two‐level energy management based on tiered demand response and energy storage systems

AbstractIn response to the escalating demands of the electricity market for load dispatch optimization and the stable operation of power systems, the design of effective incentive mechanisms to guide user electricity consumption behaviour has become an urgent task. This study addresses the complexity of the power load dispatch system by analysing the characteristics and interrelations of large‐scale user load demand responses. A dual‐layer energy management model was constructed, and a demand response incentive mechanism was designed. Adaptive incentive strategies were formulated according to different electric power user demand response scenarios. Furthermore, an optimal incentive decision‐making technology oriented towards user comfort was proposed, achieving an integrated function of strategy formulation, implementation, analysis, and optimization for power demand response. Through typical applications in core business scenarios such as elasticity of power user demand response, tiered incentive mechanisms, and comprehensive user utility, the model and strategies have been confirmed to optimize the economic benefits of virtual power plants and demand‐side electricity users under the premise of ensuring user comfort. This provides a novel solution for the efficient operation of the power market.

Monitoring Pemakaian Daya Listrik Rumah Berbasis IoT

The current prepaid and postpaid electrical payment systems still have limitation, in monitoring electrical powerconsumption. In postpaid electricity, recording through officers is still done manuallywhen monitoring electrical power usage, whereas for the prepaid system users cannot know electrical power usage in real time. Based on these conditions, a toolwas designed that capable of calculatingthe electrical power used by using home appliancesin real time and can be monitored remotely. This system is designed using the N. meanwhile, it can beode MCU ESP8266as the main controller and the PZEM-004T sensor to measure voltage (V), current(A), plectrical Powerower (W), and energy (kWh), as well as fees that must be paid (Rp) accordingly. Usage, whre the data will bedisplayed on a 20x4 LCD for on-site monitoring. Meanwhile, it canbe monitored remotely using Blynk IoT application whichis connected to the internet network. Generally this system can work with in error rate of <5%, where testing is carried out for 20 minutes for indescent lamp loads.

Analysis of the outage performance of energy-harvesting cooperative-NOMA system with relay selection methods

Recent years have witnessed the remarkable progress in wireless communication systems due to the escalating demand for higher data rates, improved reliability, and increased energy efficiency. In this regard, Non-Orthogonal Multiple Access (NOMA) has emerged as a promising technology, enhancing spectral efficiency and accommodating multiple users concurrently within the same time and frequency resources. Simultaneously, the energy harvesting has surfaced as a sustainable solution, converting ambient environmental energy into usable electrical power for operating communication nodes. This paper proposes a cooperative NOMA transmission scheme integrating energy harvesting and utilizing Least Squares (LS) channel estimation for precise Channel State Information (CSI) acquisition. The objective is to establish an optimal communication path from source to destination. Relay selection methods: Optimal Relay Selection (ORS) and Max-Min Relay Selection (MMRS), are compared, focusing on their impact on the system performance. The analysis considers the influence of the number of relays and power allocation factor on the system, with a specific emphasis on the outage probability expressions. Comparative analysis between the cooperative-NOMA and the traditional cooperative relaying without NOMA reveals the superior performance of the cooperative-NOMA. Additionally, the ORS scheme outperforms MMRS in terms of the outage performance.

Y2O3-doped BST flexoelectric ceramic energy harvester

The study employed the water-based casting technique to prepare BST sheets, which were then combined with PDMS to BST composite sheets for wind energy harvesting. By adding 0.3–1.2 mol% Y2O3 as an additive, the dielectric constant and the flexoelectric coefficient of the BST sheets were significantly enhanced. The Y2O3 and BST powders were mixed to form a casting slurry with the appropriate viscosity, which was then cast into a sheet. After the sintering process, silver electrodes were coated on both surfaces of the sheet. To enhance the flexibility of the sheet, PDMS was applied to the silver-coated surfaces, creating a "sandwich structure" composite sheet. The flexoelectric properties of the composite sheets are characterized utilized the micro cantilever beam method. The energy harvesting experiments, conducted in a simulated wind tunnel environment, demonstrate that the composite sheets exhibit varying flexoelectric properties and energy conversion efficiencies, depending on their thickness. When the doping amount of Y2O3 is 0.6mol%, the composite sheets with a BST layer thickness of 200 μm exhibit the highest flexoelectric coefficient of 1.1 μC/m; the composite sheets with a BST layer thickness of 100 μm exhibit the strongest current output capability of 4.2 nA. These findings indicate that the developed composite sheets could be promising for applications in renewable energy harvesting, particularly for capturing and converting wind energy into useable electrical power.

Energy Harvesting Floor Tile Using Piezoelectric Patches for Low-Power Applications

Abstract Purpose One of the sustainable energy sources derived from kinetic energy is human footsteps. This research sought to find a substitute for conventional power sources to lessen dependence on them. As a result, a floor tile excited by human footsteps was demonstrated and presented to generate usable electrical power. Methods Piezoelectric patches, hot melt glue sticks, wood plates, and foam plates are just a few of the commercially available materials used in the suggested technique, making it suitable and practical. In addition to the components, uncomplicated circuits like a voltage multiplier and rectifier with a capacitance filter were employed for the electrical power capture. The proposed prototype has a length of 455 mm and a width of 405 mm. Results Two LEDs were effectively illuminated as an actual load using electrical energy collected from human footsteps. The maximum useful power that could be harvested successfully via the proposed floor tile (one tile) was 246 mW, with an approximate cost of $10.2. Conclusions Designing an array of footsteps-based energy harvesting tiles covering broad areas to maximize the harvested power could be considered as a future work. Moreover, the number of pedestrians variable can be also studied for the proposed design of this study in a real excitation environment such as a railway station, subway station, street, discotheque, and wedding festival hall.

PENGEMBANGAN SISTEM ENERGI TERBARUKAN: PENDEKATAN MULTIGENERATOR DAN SIMULASI ETAP

This research focuses on the analysis of power flow in an electrical energy system involving 5 generators, with a nominal voltage of 345 KV, and a total power of 500 MW. Utilizing the ETAP simulation software, we evaluated the distribution of power, currents, and power factor across the entire system. The results of the analysis provide deep insights into the system's response to loads, power flow, and the efficiency of electrical power utilization. At the 345 KV voltage level, the simulation demonstrates the system's capability to maintain stability and power balance effectively. Power distribution and currents among generators provide a clear overview of the performance of the electrical network. Power factor analysis offers additional information regarding the efficiency of electrical power usage within the system. These findings serve as a crucial foundation for making informed decisions in managing and developing renewable energy infrastructure. In the era of transitioning towards more sustainable energy sources, a comprehensive understanding of power flow and system responsiveness to loads is essential to ensure the reliability and efficiency of the electrical power system

Design and Construction of an Internet of Things Based Electrical Power Usage Monitoring System

Design and Construction of an Internet of Things Based Electrical Power Usage Monitoring System

What is the environmental impact of a blood transfusion? A life cycle assessment of transfusion services across England.

Healthcare activities significantly contribute to greenhouse gas (GHG) emissions. Blood transfusions require complex, interlinked processes to collect, manufacture, and supply. Their contribution to healthcare emissions and avenues for mitigation is unknown. We performed a life cycle assessment (LCA) for red blood cell (RBC) transfusions across England where 1.36 million units are transfused annually. We defined the process flow with seven categories: donation, transportation, manufacturing, testing, stockholding, hospital transfusion, and disposal. We used direct measurements, manufacturer data, bioengineering databases, and surveys to assess electrical power usage, embodied carbon in disposable materials and reagents, and direct emissions through transportation, refrigerant leakage, and disposal. The central estimate of carbon footprint per unit of RBC transfused was 7.56 kg CO2 equivalent (CO2eq). The largest contribution was from transportation (2.8 kg CO2eq, 36% of total). The second largest was from hospital transfusion processes (1.9 kg CO2eq, 26%), driven mostly by refrigeration. The third largest was donation (1.3 kg CO2eq, 17%) due to the plastic blood packs. Total emissions from RBC transfusion are ~10.3 million kg CO2eq/year. This is the first study to estimate GHG emissions attributable to RBC transfusion, quantifying the contributions of each stage of the process. Primary areas for mitigation may include electric vehicles for the blood service fleet, improving the energy efficiency of refrigeration, using renewable sources of electricity, changing the plastic of blood packs, and using methods of disposal other than incineration.

Energy Management and Audit of the Lighting and Air Conditioning System at the Teratak Buluh Grand Mosque, Pekanbaru City

Energy management and audits are important steps in improving a building's energy efficiency. Mosques, as centers of religious and social activities, often have significant energy requirements. The research methods used include field observations at the Teratak Buluh Grand Mosque, measuring energy consumption, and recommendations for saving energy use. The research results show that mosques have the potential for significant energy savings with recommendations for energy conservation opportunities that can be implemented by reducing the number of lamps used and the number of air conditioners. Previously, electrical power consumption at the Teratak Buluh Grand Mosque was 74,480.40 kWh/year with electricity costs reaching IDR 68,894,370/year. Meanwhile, electrical power usage after energy conservation opportunities (ECO) is 41,918.40 kWh/year with electricity costs of IDR 38,774,520/year, with an energy consumption intensity (IKE) value at the mosque of 13.49 kWh/m2/ month. Based on Permen No. 13 Tahun 2012 Tentang Penghematan Energi Listrik, this value is included in the fairly efficient energy consumption category.

Wave Energy Conversion through Oscillating Water Columns: A Review

An oscillating water column (OWC) is designed for the extraction and conversion of wave energy into usable electrical power, rather than being a standalone renewable energy source. This review paper presents a comprehensive analysis of the mathematical modeling approaches employed in OWC systems, aiming to provide an in-depth understanding of the underlying principles and challenges associated with this innovative technology. A prominent classification within the realm of wave energy devices comprises OWC systems, which exhibit either fixed or floating configurations. OWC devices constitute a significant proportion of the wave energy converter prototypes currently operational offshore. Within an OWC system, a hollow structure, either permanently fixed or floating, extends below the water’s surface, creating an enclosed chamber where air is captured over the submerged inner free surface. This comprehensive study offers a thorough assessment of OWC technology in conjunction with air turbines. Additionally, the investigation delves into theoretical, computational, and experimental modeling techniques employed for analyzing OWC converters. Moreover, this review scrutinizes theoretical, computational, and experimental modeling methodologies, providing a holistic understanding of OWC converters. Ultimately, this work contributes a thorough assessment of OWC technology’s current state, accentuating its potential for efficient wave energy extraction and suggesting future research avenues.

Penggantian Halogen ke LED pada Runway Edge Lights Bandara Ahmad Yani Sebagai Efesiensi Energi Listrik

Jenderal Ahmad Yani International Airport is an airport located in the West Semarang District, Semarang City. This airport has departure and arrival terminals that facilitate domestic and international flights. Ahmad Yani International Airport also has a runway (13-31) with a length of 2,560 meters. There is airport lighting system equipment whose function is to assist and serve aircraft taking off and landing so that they can operate in cloudy, cloudy weather and at night in the runway, taxiway and apron areas. One of the equipment in the airport lighting system is the runway edge lights. Currently, the runway edge lights installed at Jenderal Ahmad Yani International Airport still use halogen type lights, which require quite a large amount of electrical power and the electricity costs incurred are not small. Replacing halogen type runway edge lights with Light Emitting Diode (LED) runway edge lights as an effort to efficiently use electrical energy. In this study the author used a comparative method to determine the comparison of the efficiency of using electrical energy between the two types of LED runway edge lights and halogen runway edge lights. From the comparison data carried out, it can be concluded that replacing halogen runway edge lights with LED runway edge lights has been proven to increase the efficiency of electrical power usage over a long period of time. From the specification data, LED lamps have a longer life time, namely 56,000 hours compared to halogen lamps, which is only 1000 hours, so the savings are also greater. From power calculations, it can be seen that LED runway edge lights have more power efficiency than halogen runway edge lights. The total power of halogen runway edge lights (2 circuits) was 21,480.58 watts, while LED runway edge lights (2 circuits) decreased by 56.2% to 9,400.58 watts.

Embracing the Evaporative System in Air Conditioning Technology for Efficient Cooling Solutions

The use of an air conditioning system requires large amounts of electrical energy to carry out repeated vapor compression cycles. The use of an evaporative cooling system in this research is by spraying condensate water on the condenser, which is one solution to absorb condenser heat. Another thing that can be done is to reset the fan speed on the condenser to cool it. Resetting the fan speed on the condenser can also help improve AC performance and reduce electrical energy use. The test was carried out by modifying the 1 Pk R-410a AC split condenser by installing 6 nozzles, 2 rows of 3 columns and a DC pump to spray water on the condenser. The independent variables of this research are spraying position and fan speed. The result obtained from the research is an increase in COP by 35% and a reduction in electrical power usage by 15% by using additional water spray with a nozzle behind the condenser both when blowing the full blower and when the blower blowing speed is reduced by 75%. The use of evaporative systems in air conditioning technology is a promising solution to achieve sustainable and efficient cooling solutions.

Identification and Stabilization of Constant Power Loads in AC Microgrids

Microgrids represent an attractive solution for a more flexible way to manage electrical power systems, potentially allowing for increased distributed generation and smarter usage of the available electrical power. However, the presence of power electronics and their control can challenge the system stability, especially power electronic converters with constant power load behavior. This paper considers a novel on-line load identification (OLLI) technique applied to the control of power electronic converters, as well as two control strategies to achieve stabilization of the whole system. The OLLI algorithm and the stabilizing effects of the proposed control strategies are validated through simulation and laboratory experiments, showing the feasibility of the presented work applied in future microgrids.

Sistem Monitoring Daya Listrik Berbasis Internet of Things Menggunakan Application Programming Interface (API)

The use of Internet of Things technology in power monitoring systems has become a popular solution to overcome electricity consumption problems. PT Indonesia Comnets Plus (PLN Icon Plus) is a subsidiary of PLN which operates in the field of information and communications technology. To support its business activities, until the end of 2021, this company has 26 representative offices spread throughout Indonesia. ICON+ KP Yogyakarta is one of these representative offices. Unfortunately, the ICON+ Yogyakarta Branch office often experiences power outages due to the use of electrical power that exceeds the available capacity. For this reason, this research developed an internet of things-based electrical power monitoring system to monitor electrical power usage at PT ICON+ Yogyakarta in real time.