Electrical Energy Research Articles

Improved Surface-Enhanced Raman Scattering Performance of 2D Ti3C2Tx MXene Embedded in PVDF Film Enabled by Photoinduction and Electric Field Modulation.

In this study, we introduce a synergistic approach to enhance the surface-enhanced Raman scattering (SERS) signal in two-dimensional (2D) MXene through photo-irradiation and electric field modulation. Our methodology involves the integration of 2D Ti3C2Tx MXene with piezoelectric polyvinylidene fluoride (PVDF) polymer, resulting in the creation of a free-standing, flexible composite film. On this composite film, a thin layer of Au was deposited. Our flexible substrate was able to sense methylene blue (MB), crystal violet (CV), 4-aminothiophenol (ATP), and melamine. The SERS substrate exhibits low detection limit of 10-8 M MB with a 6.7 × 106 enhancement factor (EF). The SERS substrate enables picomolar (pM) detection sensitivity for CV molecules with an EF of 9.2 × 109. Furthermore, the introduction of photo-irradiation leads to an additional ∼3.5-fold enhancement in the SERS signal, which is attributed to the altered work function and defects. The application of mechanical force to the piezoelectric PVDF/Ti3C2Tx film results in a ∼4.5-fold boost in SERS signal due to mechanical force-induced electrical energy. The fabrication strategy employed here for producing a flexible piezoelectric PVDF/Ti3C2Tx film holds significant promise for expanding the potential application of 2D MXene in rapid, on-site sensing scenarios.

Optimizing sewage water of Perum Pesona Permata Gading with the assistance of Cu/Mg electrodes as public street lighting based on green technology electricity

Electricity in Indonesia uses fossil fuels as an energy source. If fossil fuels run out, we will lose our largest source of electrical energy. Therefore, we need a way to reduce dependence on fossil fuels by making good use of renewable energy as a source of electrical energy. One of them is Green Technology Electricity with the utilization of sewage water to convert chemical energy into electrical energy. This study aims to determine the potential of sewage water assisted by Cu/Mg electrodes as a source of street lighting, manufacturing, and testing methods, and the effect of optimizing sewage water on electrical performance as street lighting. Lack of lighting in residential areas is also a supporting factor in this research. The stages used are preparation, incubation, construction assembly, research, and strength testing. Based on research, the sewage water from Perum Pesona Permata Gading can be used as street lighting with the highest potential difference and current strength being 4.4 V and 0.55 A for each 50 mL of the sewage water.

Potential of Solid Waste from Palm Oil as Fuel for Steam Power Plants in Palm Oil Factories

This research aims to analyze the potential electric energy contained in the by-products and processed waste of palm oil. Biomass derived from palm oil by-products can serve as an alternative source of energy, with potential calorific value to generate electricity from boilers or as renewable energy. While solid waste from palm oil by-products is commonly utilized as boiler fuel and fertilizer, it holds promise as a renewable energy source in its entirety. The research process includes problem identification, formulation, determination of research objectives, literature review, field surveys, primary data collection through observation and interviews, data analysis, and presentation of research results. Field observations from several visited palm oil mills reveal that solid waste by-products typically consist of 5-7% shell, 11-14% fiber, and 20-22% Empty Fruit Bunches (EFB) per ton of processed Fresh Fruit Bunches (FFB). Considering the maximum electricity requirement for processing 30 tons/hour and the potential electrical energy contained in each waste type, utilizing fiber waste alone as boiler fuel is sufficient, offering a potential electrical energy of 542.1 kW. Any excess electrical power generated (580 kW) by the boiler can be sourced from shell waste, enabling surplus electricity to be sold to external parties. With the surplus electrical power estimated at 130 – 70 kW/hour, operating for 20 hours per day yields a surplus of 1.4 – 2.6 MW/day from processing. The calorific value of solid palm oil waste is notably affected by its moisture content. Proper management of fiber waste utilization can effectively fulfill the energy needs of palm oil mills. Additionally, there is potential to sell approximately 648 – 686 kW of electrical energy externally, derived from shell waste and EFB.

Comparisons of Direct Normal Irradiation for the Optimization of Active Daylighting Systems

Active daylighting technology, encompassing techniques for utilizing natural light without converting it into heat or electrical energy, proves highly beneficial in sun-rich countries like Morocco. Unlike solar technologies, which capture global radiation, daylighting technology specifically leverages direct sun radiation. This study focuses on three semi-empirical models: Perrin de Brichambaut, Kasten, and Ghouard, utilizing data from the PVGIS website to develop and evaluate these systems. Comparison of experimentally obtained direct normal irradiation results against these models and the PVGIS website identifies the Kasten model as the most suitable choice, supported by the high R2 values of 0.9954, 0.9933, 0.9951, and 0.9906 for winter, spring, summer, and autumn, respectively. Furthermore, the model exhibits a minimum Mean Absolute Error (MAE) of 12.34, 24.29, 25.93, and 29.51 W/m², an optimal Mean Squared Error (MSE) of 238.16, 1129.5, 1039.9, and 1520.7 W²/m⁴, and a variance of 216.40, 1099.3, 1015.4, and 1460 for the respective seasons. These results strongly indicate the Kasten model's suitability for the climatic conditions of the studied site in Morocco, showcasing high correlation coefficients and low prediction errors. The findings underscore the Kasten model as the most fitting choice for optimizing active daylighting technology in Morocco's climate.

Modified lignin-based intumescent flame Retardant's effect on flame retardancy, mechanical and electrical properties of HDPE material for cable sheathing

High-density polyethylene (HDPE) is a commonly used material for cable sheathing, which is a flammable material. To ensure the safe transportation of electrical energy, it is necessary to enhance the flame-retardant properties of HDPE materials. In this work, ammonium polyphosphate (APP) with lignin (Lig) is used as an intumescent flame retardant, and the flame retardant properties of APP/Lig for HDPE with different ratios are analyzed. It is found that with 3/1 ratio of APP and Lig under 30 wt%, the best flame-retardant performance is achieved. To further improve its properties, chemical modification of Lig with hexachlorocyclotriphosphazene (HCCP) is conducted to introduce nitrogen and phosphorus, obtaining NP-Lig. Flame retardant, mechanical and electrical properties are tested for the prepared material. The flame retardant tests show that the LOI of HDPE is increased from 23.8 to 28.2 by the addition of APP/NP-Lig, compared to that of APP/Lig. Mechanical tests show that replacing Lig with NP-Lig slightly increases the tensile strength and elongation at break of HDPE. Electrical tests show that APP/NP-Lig flame retardant maintains the electrical properties of HDPE under the industry standards.

Architecture Design of High‐Performance Piezoelectric Energy Harvester with 3D Metastructure Substrate

AbstractPiezoelectric energy harvesters (PEHs) have drawn considerable attention due to their unique ability to convert ambient mechanical energy to electrical energy. These devices are widely implemented in numerous applications such as wearable technology, structural health monitoring, and renewable energy systems. In this work, a novel approach that seamlessly integrates arbitrary metastructures into the substrate layer of cantilever beam‐based PEHs is presented. The corresponding performance of each PEH design is evaluated via an experimentally validated finite element model. This is the first systematic study to explore 3D metastructures with various unit cell configurations, unit cell numbers, and porosity levels. Compared with the existing PEH designs, implementation of a 3D auxetic metastructure with 85% porosity single unit cell design can demonstrate a substantial enhancement in output power, reaching 48.16 mW, and a high normalized power density (NPD) of 2.1131 µW mm−3 g−2 Hz−1. Results show that there are competing requirements for improving the performance of PEHs. On one hand, low metastructure stiffness is preferred to achieve high power output at low resonant frequency. On the other hand, metastructures designs with low stiffness may induce excessive distortion in the substrate layer, leading to mechanical energy loss. This deformation mechanism adversely affects the mechanical to electrical energy conversion efficiency. Detailed guidelines for designing and manufacturing high‐performance PEHs are discussed in this work.

Artificial Intelligence Assisted Smart Self‐Powered Cable Monitoring System Driven by Time‐Varying Electric Field Using Triboelectricity Based Cable Deforming Detection

AbstractCable monitoring is essential for the prevention of machine malfunctions as machines are operated dynamically. Traditional methods of cable monitoring, conducted through portable or fixed devices, possess the inherent limitations in real‐time damage detection and precise location identification. Herein, a self‐powered, smart cable monitoring system is proposed, utilizing a triboelectric nanogenerator (TENG) as a sensor for the cable and an electric field energy harvester (EFEH) as a power source of the system. Also, the generated electrical outputs from the EFEH are theoretically and experimentally investigated according to the EFEH‐layer numbers, and the optimal number of EFEH‐layers is determined, generating an average electrical power of 2.04 mW. Through hybridization of TENG and EFEH, a synergistic effect is confirmed, resulting in a remarkable 155% enhancement in electrical energy. Consequently, the proposed system is endowed with self‐powered wireless communication capabilities. Additionally, employing a pre‐trained long short‐term memory‐based model, the system can predict the remaining lifespan of the cable with an accuracy rate of 93.7%. Considering these results, the proposed system demonstrates significant potential for industrial cable monitoring applications in the near future.

Photothermal conversion-enhanced thermoelectric generators combined with supercapacitors: An efficacious approach to integrated power generation and storage

Thermoelectric generators (TEGs), which harness and convert solar-thermal energy into electrical energy, possess immense potential within the field of photothermal conversion (PTC). However, the widespread adoption of conventional TEGs in PTC domain has encountered some obstacles, which represent that TEGs have poor inherent PTC performance, resulting in low solar-thermoelectric conversion efficiency, and this solar-thermal-electric conversion method lacks the capability of electrical energy storage. Hence, an urgent imperative exists to develop integrated and synergistic energy technologies that can respond to these underlying challenges. Herein, we reported a novel strategy for employing spinel-type Cu1.5Mn1.5O4 PTC coating to adorn conventional TEG to construct the solar-thermoelectric generator (STEG) which exhibited excellent solar-thermoelectric conversion capability, and then integrating the STEG in series with a supercapacitor composed of synthetic ionic liquid electrolytes and carbon electrodes to fulfill the conversion and storage of solar-thermal energy into electrical energy. The results indicated that, when compared to a conventional TEG, the STEG attained a drastically elevated internal temperature difference due to the excellent PTC capability of spinel-type coating. As a result, remarkable enhancements were observed in both the steady-state voltages (Voc) and maximum output power density (Pmax) of the STEG, exceeding a 6-fold and 40-fold increase, respectively. Furthermore, we conducted experimental validation to ascertain the viability of the solar-driven STEG to charge a supercapacitor, thereby achieving the conversion and storage of solar-thermal energy into electrical energy, and the working mechanism of this integrated system has been revealed. This study offers invaluable insights into the development of highly efficient solar-thermal energy conversion and storage methods.

Thermodynamic performance investigation of environmentally friendly working fluids in a geothermal integrated pumped thermal energy storage system

Abstract Among the available energy storage technologies, pumped thermal energy storage (PTES) is emerging as a potential solution for large-scale electrical energy storage with no geographical limitations and high roundtrip efficiencies. However, PTES requires a low-cost, high-temperature heat source to achieve reasonable roundtrip efficiencies. Moreover, organic Rankine cycle-based PTES systems require high-performance and environmentally friendly working fluids. In this study, the thermodynamic performance of a geothermal integrated PTES system using environmentally friendly working fluids is investigated. The mathematical model of the geothermal integrated PTES system is developed using the first and second laws of thermodynamics and implemented in Engineering Equation Solver (EES). With the developed model, the thermodynamic performance of the PTES system for different working fluids, including Butene, cyclopentane, iso-butane, R1233zd(E), R1234ze(Z), R1224yd(Z), HFO1336-mzz(Z), R365mfc, n-hexane, and n-pentane was investigated. For geothermal fluid outlet temperatures between 60°C and 120°C and geothermal fluid inlet and outlet temperature differences across the evaporator between 20°C and 60°C, the net power ratio i.e., the ratio of the electrical energy discharged to the electrical energy used to run the charging cycle, is between 0.25 and 1.40. This shows that the system has the potential to give back more than 100% of the electrical energy used during charging under certain conditions. High net power ratios are obtained for a combination of high source temperatures and low geothermal fluid inlet and outlet temperature differences.

Modeling favorable locations for biogas plants that generate electricity from dairy and beef cattle manure through mixed integer linear programming

Mixed integer linear programming (MILP) is known as a type of programming that can combine continuous variables, integer variables, and (0-1) variables in the same algorithm and generate fitting results for the data. Using this technique, it is possible to model and solve complex problems in many different fields such as economics, biology, engineering, etc. In the present study, a regional planning model was developed using MILP technique for the conversion of manure from dairy and beef cattle into biogas and electrical energy. For this regional planning study, considering the locations of future facilities, data on dairy and beef cattle in the Isparta province of Türkiye were used. According to the model written and solution outputs, to utilize all manure obtained from dairy and beef cattles in Isparta, 5 biogas plants with a total manure processing capacity of approximately 522,000 tons should be built in different districts. It is possible to produce a total of approximately 21,000,000 m3 of biogas and 38,500 MW of electricity per year in these biogas plants. This electrical energy obtained can meet 3.83% of the annual electricity consumption of Isparta province.

Optimal energy scheduling for residential consumers with demand management strategies

ABSTRACT The enhancement of energy networks and cost reduction can be achieved through the implementation of solutions like optimal energy scheduling for residential consumers. This paper proposes day-ahead electrical and thermal energy scheduling for residential sections in energy networks as a bi-criteria optimization approach. The bi-criteria optimization approach is modeled to minimize the operation cost and maximize the reliability of the energy system. Demand management strategies such as demand reduction and demand shifting are considered for residential consumers. The participation of residential consumers in demand management is presented considering electricity prices in the energy markets. The solving bi-criteria optimization approach is done via the weight sum method and LINMAP procedure-based-fuzzy approach. The proposed modeling is implemented in GAMS optimization software for verifying the demand management strategies in optimal energy scheduling in two case studies.

Dehydration and Environmentally Friendly Thermal Processing of Excess Activated Sludge

Introduction. Currently, there is a problem with the accumulation of large amounts of production waste. One type of this waste is excess activated sludge, which is a waste product from biological wastewater treatment that has a high moisture content. When excess activated sludge is deposited in beds, problems can arise related to changes in the gas-air environment, the release of unpleasant odors, as well as the contamination of groundwater and soil. Prolonged presence of sediment in sludge beds in oxygen-free conditions leads to its decay and deterioration of moisture-yielding properties. For these reasons, the development of new methods for disposing of large volumes of waste generated during wastewater treatment is essential. The aim of this research is to develop a technique for preliminary neutralization and thermal treatment of excess activated sludge using energy waste. Materials and Methods. The work used excess activated sludge with a moisture content of 98.2% (waste of hazard class IV). Water treatment sludge (waste of hazard class V) was used as a reagent to increase moisture yield. For experimental studies on dehydration, a laboratory centrifuge Elmi CM-6M.01 was used. Tests were conducted under various conditions (500, 1 000, and 1 500 revolutions per second for 1, 2, and 3 minutes), and the value of centrifugation was determined as a criterion for moisture yield in the sludge. Fuel pellets were produced by rolling with technical lignosulfonate as a binding agent. Elemental analysis of the samples was conducted to study the possibility of thermal treatment using an EA 3 000 Euro Vector Analyzer. Results. A comprehensive technology has been developed to clean the resulting gas emissions from solid particles formed during the combustion of fuel pellets and remove them from the furnace in the form of fly ash along with the outgoing gases. This technology also removed sulfur oxides, nitrogen oxides, and polychlorinated dibenzodioxins and dibenzofurans, while beneficially utilizing flue gas heat by reducing its temperature from 900–1 200°C to 140°C. Discussion and Conclusion. The approach proposed in this article for the processing and disposal of large volumes of waste allows for the reduction of moisture content of excess activated sludge and the use of this waste as a secondary energy source. This method is environmentally friendly and addresses both technical and environmental challenges, such as the effective recycling of industrial waste and reducing the anthropogenic impact on soil, air, and groundwater. It also provides an opportunity to generate additional electrical and thermal energy through thermal utilization of waste. The results of this work indicate that it is possible to integrate the use of various types of industrial waste (sewage sludge, water treatment waste, and pulp and paper industry waste) as secondary energy sources. These findings have practical implications for enterprises in both the municipal and industrial sectors with wastewater treatment facilities.

MODELING AND OPTIMIZATION OF A PCM-BASED OCEAN THERMAL ENERGY HARVESTER FOR POWERING UNCREWED UNDERWATER VEHICLES

Abstract As oceans cover over 70% of the planet's surface, they represent a large reservoir of resources that remained vastly untapped. Uncrewed Underwater Vehicles (UUVs) are becoming key technology for ocean exploration. Ocean thermal gradient is a permanent and reliable energy source that can be used to power UUVs using phase change material (PCM)-based thermal engines. When using PCM-based thermal engines to power UUVs, there are different energy conversion stages, thermal, hydraulic, kinetic, and electrical, dependent on a wide variety of parameters. Thus, optimization of the overall energy conversion is still a challenge for powering the increasing energy demanding UUVs for long missions. The goal of this study is to propose a PCM-based ocean thermal energy harvesting system for powering float type UUVs such as the Solo II float. This reduces the cost for battery replacement and expands the float's mission time. For this purpose, we developed a model consisting of hydraulic and electrical systems, designed to provide the electrical power needed by the UUV. The hydraulic and electrical systems are implemented using MATLAB-Simulink. The model developed can provide 13.66 kJ of electrical energy, which is more than 1.5 times the energy requirement per cycle for the SOLO II float.

A two-tier bidding model considering a multi-stage offer‑carbon joint incentive clearing mechanism for coupled electricity and carbon markets

To facilitate the coupling of electricity and carbon markets, a two-layer bidding model considering a multi-stage offer‑carbon joint incentive clearing mechanism is proposed. The upper layer models the bidding strategies of renewable energy units and thermal power generating units, and the lower layer is the market clearing layer. A multi-stage offer‑carbon joint incentive clearing mechanism is proposed. In the pre-clearing stage, the environmental benefit factor of the carbon market is introduced to adjust the bidding strategy of the units, the carbon emission intensity enters the market in the form of price, the environmental benefit of the generating units is fully considered, and the carbon quota allocation model of units is established; in the second stage, carbon trading cost is added based on the pre-clearing model to further optimize the unit output; in the third stage, the clearing model with the minimum cost of electricity energy is established for tracking the clearing price. Under this mechanism, the carbon trading cost is traded on the market and unit offers are combined with carbon element to participate in market trading. Three bidding models with different clearing mechanisms are set up, and the results of the arithmetic example show that the proposed model can realize the balance between the economic and low-carbon goals of market clearing, and can achieve the maximum carbon emission reduction based on no increase in the total cost of electric-carbon coupling. As the share of renewable energy increases, the clearing price will decrease. A reasonable offer from renewable energy sources can avoid their interests being jeopardized. Concurrently, increasing the initial carbon price can effectively guide the electricity market to develop in a cleaner direction.

Stable Photo-Rechargeable Al Battery for Enhancing Energy Utilization.

Photovoltaic cells (PVs) are able to convert solar energy to electric energy, while energy storage devices are required to be equipped due to the fluctuations of sunlight. However, the electrical connection of PVs and energy storage devices leads to increased energy consumption, and thus energy storage ability and utilization efficiency are decreased. One of the solutions is to explore an integrated photoelectrochemical energy conversion-storage device. Up to date, the integrated photo-rechargeable Li-ion batteries often suffer from unstable photo-active materials and flammable electrolytes under illumination, with concerns in safety risks and limited lifetime. To address the critical issues, here a novel photo-rechargeable aluminum battery (PRAB) is designed with safe ionic liquid electrolytes and stable polyaniline photo-electrodes. The integrated PRAB presents stable operation with an enhanced reversible specific capacity ≈191% under illumination. Meanwhile, a simplified continuum model is established to provide rational guidance for designing electrode structures along with a charging/discharging strategy to meet the practical operation conditions. The as-designed PRAB presents an energy-saving efficiency ≈61.92% upon charging and an energy output increment ≈31.25% during discharging under illumination. The strategy of designing and fabricating stable and safe photo-rechargeable non-aqueous Al batteries highlights the pathway for substantially promoting the utilization efficiency of solar energy.

Enhancing Visual Comfort and Energy Efficiency in Office Lighting Using Parametric-Generative Design Approach for Interactive Kinetic Louvers

The number of desk workers who frequently conduct their jobs at home has increased dramatically during Covid-19. Work-from-home flexibility makes it attractive for workers and companies, resulting in a “Work-Style Reform” after the Covid-19 pandemic. However, the quick conversion of home spaces into workplaces cannot always sufficiently respond to users’ visual comfort and daylight performance needs which are primary contributors to occupant well-being and productivity. Therefore, this study adopts a mixed-methodology method that integrates parametric thinking, biomimetic, conceptual design, kinetic strategy and the DIVA approach to develop a real-time parametric-generative circular design for multi-objective adaptability that optimizes visual comfort and electric lighting energy efficiency for multiple occupants simultaneously. Parametric simulations of 1458 different options (five different runs per case: a total of 7290) were conducted to assess how the louvers perform regarding daylight, glare, and electric energy usage. Implementing an interactive kinetic louver greatly improved daylight performance in all orientations while simultaneously avoiding visual discomfort for multiple occupants. Furthermore, the use of this façade modification resulted in a substantial decrease in electrical lighting energy consumption, reducing the values from 14.22 to 0.2 kWh/m2/year, 8.1 to 0.18 kWh/m2/year, and 12.88 to 0.18 kWh/m2/year for South, East, and West orientations, respectively. Integrating users' lighting level preferences and the dynamic transitory sensitive area on the façade considerably reduces electric lighting consumption by around 99% compared to the ASHRAE 90.1 standard's lighting profile.

On reliability and quality of functioning of power grids (as exemplified by the branch of PJSC Rossetti Volga – Samara Distribution Networks)

The analysis of the electric energy transmission through the distribution electric networks of the branch of PJSC Rosseti Volga — Samara Distribution Networks over the period of 2018 – 2022 was carried out. The structure of the company is considered, the characteristics of the main elements of the power grids under study are given, the balance of the electric energy transmission in and out of the company's networks is estimated. Based on the information published in public media on the accident rate in the company's power grids, assessment was made of the number of emergency situations that occurred over the period under study, assessment of the duration of interruptions in power supply to consumers, as well as the amount of undersupplied electric energy caused by these interruptions. The influence of the seasonal component on the number of emergencies during the period under study is considered. Based on the 2022 data, the analysis of the main causes of damage to components of power grids and the classification of failures are presented, their main characteristics over the period in question are considered. The percentage ratio of the number of failures for the most characteristic reasons to the total number of shutdowns over the period under study was established, and the classification of the number of emergency shutdowns according to the degree of undersupply of electrical energy was made. General scientific methods, numerical methods of analysis, methods of the electrical circuit theory were used in the study. To visualize the results of the analysis, the technologies of the MATLAB graphics editor were used. The results obtained may be of interest to the heads of power grid companies, as well as researchers and engineers engaged in research in the field of power supply reliability.

First‐Principles Investigations of Lithium Manganese Phosphate Cathode Materials: Advances and Prospects

Lithium manganese phosphate (LiMnPO4) has been considered as promising cathode material for electric vehicles and energy storage. However, its durability and capability still face challenges. The first‐principles calculations are a powerful tool to explore the fundamentals of LiMnPO4 cathode materials. Hereby, the recent advances and prospects in the application of first‐principles calculations boosting LiMnPO4 cathode material for lithium‐ion batteries are analyzed and reviewed. Based on the results from density functional theory calculation and experimental research verification, the micromechanism research progress of the influence of ion doping on the electronic conductivity, lithium‐ion diffusion, working voltage, and stability of LiMnPO4 are summarized in detail. On top of a brief outlook, further elaboration is made on the direction of continuing relevant research.

Scrap Steel Recycling: A Carbon Emission Reduction Index for China

Accurately assessing carbon emissions from recycling scrap steel is essential for reducing emissions in the steel industry, especially in China, the world’s largest crude steel producer. In this study, a carbon emission reduction index was introduced to evaluate the effectiveness of recycling scrap steel in reducing emissions. The index considers the three processes used in scrap steel recycling: blast furnace ironmaking, converter steelmaking, and electric arc furnace steelmaking. This study developed an evaluation model using fuzzy analytic hierarchy process and iterative cluster analysis to determine the reduction of carbon emission. From a life cycle perspective, this study identified primary factors contributing to emissions, including fuel, raw materials, electric energy, and auxiliary materials. Then, the carbon emission reduction index for scrap recycling was developed by examining the production of one ton of steel and each additional ton of scrap steel, which can provide valuable insights into the environmental impact of scrap recycling. Finally, the study forecasts the future Carbon Emission Reduction Index for steel scrap recycling. The study indicates an increase in the carbon emission reduction index for scrap recycling prior to 2017, followed by a decrease about 11.8% from 2017 to 2018 and increases from 2018 to 2021. Finally, it dropped by 8.7% per cent in 2022. Similarly, the carbon emission reduction index for electric furnace steelmaking increased prior to 2019, then subsequently decreased. It is changing by ten per cent a year. Additionally, the scrap recycling index experienced a significant decrease of 90% in 2015, followed by a gradual increase until 2017 and then a consistent decrease every year thereafter. The index suddenly rose in 2021 and then decreased change for policy reasons. The forecast results suggest a gradual increase in the carbon emission reduction index per ton of steel scrap in the future. In conclusion, the practicable modeling methodology has the ability to assist government organizations and private enterprises in devising efficient green and low-carbon development tactics.

Pengaplikasian Panel Surya dan Automatic Transfer Switch (ATS) untuk Menggerakkan Pompa Tanaman Hidroponik sebagai Sumber Energi Terbarukan

Solar panels are renewable energy which is very useful for agricultural needs to meet electricity needs, one of which is its application in agriculture, namely as a pump driver for hydroponic plants. Hydroponics is farming with an emphasis on meeting the nutritional needs of plants using water as a medium with a nutrient solution as fertilizer. In the hydroponic system the pump must be on continuously, for this reason the Automatic Transfer Switch (ATS) tool is used to substitute the electrical energy of the State Electricity Company (PLN) with the electrical energy of solar panels in the event of a power outage from the State Electricity Company (PLN) which aims to drain nutrient water. This research aims to apply solar panels to a hydroponic plant system and apply the Automatic Transfer Switch (ATS) tool as a substitute for the State Electric Company's (PLN) electrical energy and solar panels. This research was carried out on Jalan Polonia no.11 fresh water east, North Padang District, Padang City, West Sumatra in January – March 2024, with the initial stages (1) preparation, (2) solar panel assembly, (3) analysis of test results , (4) preparation of reports. The results of this research can determine the power output required by solar panels as a renewable energy source as well as the application of the Automatic Transfer Switch (ATS) in hydroponic plant cultivation.