bluuebunny/crossref_metadata_2025 huggingface dataset:
Energy Efficiency Analysis in a Textile Company Using DMAIC Approach
Authors: Sakti S , Sopha B M , Saputra E S T
Published: March 2021

Textile industries generally consume a significant amount of electricity in their business operations, hence, efforts to reduce their consumption is necessary. This study assesses the energy consumption and energy saving opportunities in a textile company in Indonesia. A structured energy audit using Define-Measure-Analyze-Improve-Control (DMAIC) was implemented in the Spinning department. The evaluation indicates that 80% of the Specific Energy Consumption (SEC) are dominated by the factory air conditioner and chiller which is corresponding to 515 kWh/kg and 219 kWh/kg respectively. The Coefficient of Performance (COP) of the plant cooling system is 7.41 which conforms to the COP national standard. Further energy-saving opportunities include closing the door and other gateways of the air, replacing the refrigerant material from Freon R-134 to Musicool Mc-134, and installing inverter on mist nozzle motor, evaporator pump, condenser pump, and cooling tower.
Development of an Electronic Reverse Logistics Network Model: A Literature Review
Authors: Sari D P , Masruroh N A , Aasih A M S
Published: March 2021

The rapid development of technology and economy makes consumption of electronic products increased, so the potential for electronic waste will also increase. However, the high potential of this flow has not been matched by good waste management, especially in developing countries. One concept that can be applied to manage end-of-use products is reverse logistics (RL). Still, the RL concept, especially for electronic waste has not been practiced optimally. Therefore, it is necessary to have an RL management network on electronic waste to reduce the environmental impact and increase the economic value of waste. This study aims to explore the research progress of RL networks and recommended opportunity areas for further research using bibliometric analysis and systematic literature review (SLR). The output of bibliometric analysis is research trends on the topic of reverse logistics. The search process of bibliometric analysis is still limited to the keywords has not been done in-depth study of the contents of each article, so it needs to be continued with SLR. Articles obtained from bibliometric analysis are reviewed and analyzed using SLR so that the articles will be filtered and the numbers become smaller, so research opportunities in RL for electronics product can be identified.
A Cut-Off Grade Optimization Model in Open Pit Mining Considering Reclamation Cost and Revenue
Authors: Baidowi N , Rosyidi C N , Aisyati A
Published: March 2021

In open pit mining industry, cut-off grade has an important roles in affecting the total profit that will be earned by the company. In this research, cut-off grade optimization model is developed for open pit mining industry to maximize the total profit. We consider the environmental aspect in this model which consists of reclamation cost and reclamation revenue. We also consider the revenue of sales and valuable wasted materials revenue, and also the cost of selling stage, processing cost, mining cost, waste removal/rehabilitation cost and fixed cost. The results show that the model is able to determine the optimal cut-off grade and total profit that will be earned by the company can be estimated. Besides that, we can also estimate the completion time of mining project and the value of Net Present Value (NPV) and Return on Investment (ROI). The application of the model can be illustrated using numerical example that given in this study.
A Truck Allocation Optimization Model in Open Pit Mining to Minimize Investment and Transportation Costs
Authors: Isnafitri M F , Rosyidi C N , Aisyati A
Published: March 2021

In this research we developed an optimization model to determine truck allocation in open pit mining. The objective function is to minimize a total cost consists of investment and transportation costs. Investment cost is the purchase price of truck in early mining project according to the number of truck needed in each route. The transportation cost consists of fix cost for operators’ wages and variable cost in the form of fuel cost of trucks and shovels. The selection of truck types with different specifications is an important factor in the continuity of materials transportation by considering the costs incurred The model is solved using Oracle Crystal Ball Software for 5000 iterations. The result of optimization shows that Truck 75570 is selected to transport for route 1 and Route 4, Truck 75174 is selected to transport for Route 2, Truck 772 is selected to transport for Route 3, Truck 777F is selected to transport for Route 5, and Truck 7547 is selected to transport for Route 6. The total cost resulted from the optimization is IDR 295,783,073,068.69.
Development Models of Personality, Social Cognitive, and Safety Culture to Work Accidents in the Chemical Company
Authors: Sari R N , Dewi D S
Published: March 2021

Mental errors caused by anxiety, attitude, fear, stress, personality, or emotional state can cause accidents. To prevent workplace accidents, understanding the workers’ personality that reflect the pattern of psychological characteristics, thought, emotion and behavior is important. Personality is a basic human characteristic that is influenced by the social and cultural environment called socio-cognitive. A safety culture approach to the reducing accidents emphasizes the role of social forces in organizations regarding safety. This study aims to determine the relationship of personality, social cognitive, and safety culture to workplace accidents in the chemical company. The data was collected by distributing questionnaires to 73 workers, including the production area and the field workers in a chemical factory. The data is statistically tested by using PLS-SEM. The PLS-SEM used to determine the relationship between personality traits and safety culture (H1), the relationship between social cognitive and safety culture (H2), and the relationship between social cognitive and personality traits (H3) in chemical company. The test results show that the three hypotheses were accepted. This lead to the conclusions that personality traits have a positive relation to the safety culture; social cognitive have a positive relation to safety culture; and social cognitive have a positive relation to personality traits. In conclusion, personality traits, social cognitive, and safety culture are interrelated.
Design a Mechatronic System (Robot) to Transfer Table Tennis Balls
Authors: Rahman Md M , Yahya W J , Mondal K
Published: March 2021

Advancement of technology and human needs has contributed to the convergence of multiple engineering disciplines. Mechatronics engineering is an applied discipline that focuses on the design and study of complete engineering systems including mechanical, electrical, electronic, and control systems. This paper is concentrated on design a mechatronic system (robot arms) to transfer Ping-Pong balls. The aim of this paper is to explain the design process of producing a robot that will compete in a competition. The robot will be operated either wired or wireless within its designated area in performing the ball collection during a two-round match. Duration of 10 minutes is going to be allocated for every round. Top two teams that collect most balls between the 2 rounds will proceed to subsequent round (if quite 4 teams are competing). The performance evaluations will be in terms of number of Ping-Pong balls successfully placed inside the collection buckets.
Simulation of Thermal Dispersion in Location of Development of Diesel Power Plant Using Computational Fluid Dynamics Methods
Authors: Suryo M.S.K.T. , Yohana E. , Restiana T. , Gunawan R. , Rozi K.
Published: March 2021

Electrical energy is one of the important energy needs in human life. To meet the electricity needs in the North Maluku area, it was planned to build a diesel power plant (PLTD) in the coastal area of Halmahera. In the activity of the power plant, it produces heat wastewater from the rest of the radiator cooling process. This study, conducted a numerical simulation to determine the thermal dispersion pattern of waste heat from PLTD cooling water in Halmahera waters. Modeling the dispersion of heat waste temperature of PLTD cooling water is carried out using the Ansys CFD (Computational Fluid Dynamics) method in 3D. The input data are in the form of heat water discharge of 4,000 tons/hour, with heat wastewater temperature 37.5 °C. Ambient seawater temperature is 30.5 °C and seawater density is 1022 kg/m3. Hydrodynamic modeling of oceanic currents is modeled with two variations, namely constant current of 0.4 m/s and UDF current. UDF currents have different current values for each depth with a current velocity of 0.005 m/s up to 0.4 m/s. The simulated results of a constant current show the spread of heat to the environment occurs as far as 210 m to the north of the discharge outlet. The highest temperature value is 37.14°C, the lowest is 30.8°C. For these UDF current models, the heat spread is 210 m to the north of the discharge outlet with the highest temperature value is 37.13°C the lowest is 30.61°C.
Utilization of Bamboo Fiber in the Development of Environmentally Friendly Composite – A Review
Authors: Pramudi G , Raharjo W W , Ariawan D , Ubaidillah  , Arifin Z
Published: March 2021

This paper will review the parameters that affect the tensile strength of the use of bamboo fibres in thermoplastic composites. Natural fibres considered to be more environmentally friendly and easily degraded than synthetic fibres. Bamboo has a tensile strength that is not inferior to synthetic fibres. The tensile strength of bamboo fibres influenced by the parameters from the original physical properties of bamboo. The parameters that influence are species, age, and bamboo parts. This difference generally caused by lignin content in bamboo fibres. Lignin content will reduce the tensile strength of fibres. Therefore, bamboo fibre treatment applied as an effort to reduce lignin levels. Various treatments with chemical solutions have bee proven to reduce lignin levels. The selection and proper treatment of bamboo fibres will increase the tensile strength of the fibre. There will also affect the bond between the fibre and the matrix. However, in general, the relationship between natural fibres and thermoplastic matrices is bad. There is because there is no match between natural fibres and thermoplastic matrices. So, the selection of a matrix that matches the characteristics of the fibre must be considered. Pure and recycled matrix have very different characteristics and tensile strengths. In this paper, We have reviewed various sources of bamboo fibres, mechanical properties, modification of bamboo fibres, and effects of treatment on bamboo fibres. The main applications of bamboo have bee summarized as well as effective use as reinforcement for composite polymers.
The Characteristics of LPG Detonation Wave Propagation Behind Porous Media Model
Authors: Sentanuhady J , Tuasikal J A , Prasidha W , Majid A I
Published: March 2021

LPG-air mixture enriched with oxygen is usually used for generating heat in industry sector. However, it is possible that LPG-oxygen will mix and react independently and the mixture could generate detonation wave. This condition could harm people, environment, and piping system, thus detonation quenching to guarantee safety becomes very important. The present study aims to investigate the characteristics of the detonation wave after propagating through the porous media model. The experiments used a detonation test tube with 50 mm of inner diameter and 6 m of total length. The test tube consists of two sections, 1 m long driver section and 5 m long driven section. The driver section and driven section are separated by Mylar film to prevent mixing between driver gas and driven gas, which consists of different gas mixture with different pressure. The driver section contained a stoichiometric H2-O2 mixture at constant initial pressure, which function as a direct initiator for detonation in the driven section. Besides, the driven section contained a stoichiometric mixture of LPG-oxygen and LPG-air at the initial pressure varied from 20 kPa to 100 kPa with an interval of 10 kPa. The stainless-steel porous media with masses of 15 g and 20 g were inserted in a cylindrical case which had been perforated with small holes on its cross-sectional surface to enable detonation wave to propagate through it. The observation of detonation wave propagation was conducted at upstream and downstream of the model. Two mechanisms of detonation wave propagation were observed in the downstream of the porous media model for combustion of the LPG-oxygen mixture; they are detonation re-initiation and detonation transmission. However, the LPG-air mixture could not generate a detonation wave. Additionally, the 5 g increments of the stainless-steel porous media mass only significantly increase the re-initiation distance of detonation (Dri) for mixture with low initial pressure, 20 kPa up to 50 kPa and did not significantly influence re-initiation distance of detonation for mixture with a high initial pressure of 60 kPa to 100 kPa.
The Effect of T6 Heat Treatment on 7075 Aluminum on its Hardness and Tensile Strength
Authors: Darsono F B , Koin S T
Published: March 2021

This study aimed to determine the effect of T6 heat treatment on 7075 aluminum on its hardness and tensile strength. The T6 heat treatment process was heating the test specimens in an oven at various temperatures of the solution heat treatment (SHT) of 350°C, 400°C, 450°C, and 500°C for 2 hours. This process was then followed by quenching for 45 minutes and an artificial aging process at temperature of 120°C for 48 hours. The tests carried out included: Vickers hardness test, tensile test using ASTM B557-84 standard, microstructure test, and XRD test. The test results showed that the hardness and tensile strength before T6 heat treatment were 59.1 VHN and 235.7 MPa, respectively. After the T6 heat treatment was carried out, the hardness results were 105.8, 87.3, 108.9, and 171 VHN and tensile strength of 318.3, 415, 571.7, and 618.3 MPa, respectively. These results indicated that highest hardness was found in the SHT temperature of 500°C, while the increase in tensile strength was found in the temperature of SHT 500°C. It can be obtained because the formation of precipitate after the artificial aging process was due the formation of Al2CuMg and MgZn2.
Determining Water Content of Non-Surfactant Emulsion Fuel Using Bomb-Calorimeter
Authors: Sugeng D A , Abrori M , Syafrinaldy A , Kadir H A , Saputro F R , Kusdi B H , Bahiudddin I , Yahya W J
Published: March 2021

Non-surfactant Water-in-Diesel emulsion fuel (NWD) has short stability period and tend to separate immediately into water and diesel. NWD needs to be supplied into the diesel engine or combustor as soon as it was formed. Since the combustion and emission performance are closely related to the water content of an emulsion fuel, the immediate water content of NWD needs to be more closely inspected. The ASTM D95 standard provides a method to determine the water content of an NWD, but this method takes a long time to perform (up to 2 hours) and arduous. This paper describes the estimation of water content in a non-surfactant emulsion fuel by bomb-calorimetry, which can deliver quicker results than ASTM distillation. Experiments were performed with samples of emulsion fuel using and void of surfactant. The samples were first homogenized using an ultrasonic bath before they were sent to a bomb-calorimeter. The higher heating value of the emulsion was estimated using the weighted average since the components were deemed to be non-reactive. The bomb-calorimetric results of the non-surfactant emulsion fuel showed a close proximation, while the emulsion fuel with surfactant delivered less conclusive results. It was concluded from this study that an estimation of water content in NWD could be performed using bomb-calorimetry eight times faster than using the ASTM D95 standard with a deviation of maximum 3%.
Effect of Ceiba pentandra Biodiesel/Dexlite Diesel Blends on the Four-Stroke Diesel Engine Performances
Authors: Widjanarko D , Kusumaningtyas R D , Jamari I P
Published: March 2021

The increasing number of motorized vehicles causes an increase in fuel consumption. Meanwhile, fuel consumption in Indonesia is inversely proportional to the amount of oil production in Indonesia. One of the solution in by using biodiesel from kapok (Ceiba pentendra) seed as a diesel fuel blends. In this research, blends of dexlite (diesel fuel)/Ceiba pentandra biodiesel was studied on the four stroke diesel engine performance. Four different fuel blends (B10, B20, B30 and B40) and B0 (pure dexlite fuel) were prepared for the engine performance test. The engine performance shows that addition of biodiesel to diesel fuel gave lower torque than the dexlite fuel. Biodiesel blends also have lower brake power compared to the dexlite fuel. Among different biodiesel blends, A 10% biodiesel blend shows the best engine performance in terms of engine torque and brake power.
Application of Elliptical Blade Shape to Enhance Power Generation of the Savonius Water Turbine
Authors: Sutaji A , Yusvika M , Tjahjana D D D P , Hadi S
Published: March 2021

Sewerage pipelines found in the buildings can be used as a mechanical energy resource for small capacity hydropower plant. The utilization of energy sources can be generated by installing the savonius hydrokinetic turbine. Conventional turbine is designed with semi-circular blades able to generates its own performance, but is still relatively low. In this research, the savonius type elliptical blades are applied to enhance the turbine performance. This experimental observation are conducted to obtain the optimal number of blades, which is determined by the maximum power generated by the rotor. The number of blades are tested for 2, 3, and 4 blades with four differences of the water discharge. A single-stage horizontal axis savonius water turbine (HAWT) was installed in a 3 inches diameter pipelines. The results of the experiment show that at four numbers of the blade, obtained the optimal power of 4.251 Watts at a discharge of 5.826 x 10−3 m3/s with tip speed ratio (λ) 2.37 and the coefficient of power (C

P
) 0.025.
Solar Cell Cooling with Phase Change Material (PCM) for Enhanced Efficiency: A Review
Authors: Seto D B , Kristiawan B , Ubaidillah  , Arifin Z
Published: March 2021

This literature aimed to explain recent studies related to the passive cooling of solar cells using Phase Change Material (PCM). Cooling is done to reduce operating temperature and to prevent a decrease in efficiency in an unfavorable environment because the efficiency of the solar cell system decreases when the operating temperature rises and can damage the PV module. The successful use of phase change materials (PCM) from latent heat storage systems is highly dependent on the thermal reliability and stability of the phase change materials used. In conclusion, the overall energy utilization ratio of cooled PV using a PCM system can be increased through a thermal regulation strategy, further research of this system is still needed to achieve maximum results in PV efficiency.
Noise Quality and Muffler Design of A Formula SAE Racecar
Authors: Masa’id A , Ubaidillah  , Lenggana B W , Pratama D R , Maharani E T , Sinaga F R
Published: March 2021

Mufflers are an essential part of the engine system and commonly used in the exhaust system to minimize sound transmissions caused by exhaust flow. The primary objective of a muffler is to reduce engine noise emission. Mufflers have a sophisticated design that affects fuel efficiency, noise characteristics and emission of engine. In the selection of a muffler for an internal combustion engine of a Formula SAE, several functional requirements should be considered, which include both acoustic and non-acoustical design issues. Attention must also be given to problems of space availability and configuration. The best material for the purpose must be chosen. Equally important is the most economical utilization of this material, both from the standpoint of original availability and cost, as well as the practical aspect of ease of production. Not only the basic acoustical design but also some of the problems of fabrication and attachment will be discussed.
Design Low Cost and Contactless Temperature Measurement Gate Based on the Internet of Things (IoT)
Authors: Ramelan A , Ajie G S , Ibrahim M H , Pramono S , Rizqulloh M A
Published: March 2021

Temperature measurements in preventing the spread of Covid-19 will be carried out automatically using a gate equipped with a temperature sensor. This tool is designed in a portable way, allowing monitoring of body temperature data at certain locations utilizing cloud-based technology provider services Internet of Things (IoT) that is integrated with device medical assistance (the nearest hospital). Hence, it can be followed up to get the first treatment. The hardware design of this device is equipped with an LED running text to display a person’s body temperature in real time and also an alarm for the body temperature measured to exceed the threshold. The software design uses the Wi-Fi protocol to process data from sensors for monitoring by end-users in the form of mobile or web app via the server cloud platform by HTTP Post protocol. The results showed that CTM-IoT has a precision of 99.8% and an accuracy of 99.6%. This tool is suitable to be implemented at gate terminals, stations, airports, malls, etc. without being operated directly by officers at close range.
IoT Based Building Energy Monitoring and Controlling System Using LoRa Modulation and MQTT Protocol
Authors: Ramelan A , Adriyanto F , Hermanu B.A.C , Ibrahim M H , Saputro J S , Setiawan O
Published: March 2021

Building energy monitoring systems are carried out to facilitate the monitoring and controlling of building energy consumption. Monitoring and controlling the use of electrical energy in real-time in a building has an impact on the pattern of regulating the efficiency level of energy use. This paper presents an effort to optimize energy consumption by using an energy management system using LoRa modulation and MQTT protocols. Sensors that feed electrical power data to a custom energy monitoring system are compiled by a set of sensors equipped with a power supply that is fastened to the system on a microcontroller with a LoRa communication interface then are called nodes. The nodes consist of arduino uno as a microcontroller, dragino LoRa Shield, ACS712 current sensor, ZMPT101B voltage sensor, and relay. Dragino LoRa Gateway LG01-N is used to connect the measured parameters to the IoT cloud server. MQTT protocol is used for the broker between nodes and servers using subscribe and publish method. In the initial experiments, the data visualization platform used was the open-source thingspeak platform. This platform includes a data visualization template and enables device control for savings. In the end nodes, the voltage, current, and power sensor accuracy error are 1,24%, 2.60%, and 3.13%.
Web-Based Telegram Chatbot Management System: Create Chatbot Without Programming Language Requirements
Authors: Hasyim M W , Pramono S , Sutrisno
Published: March 2021

The growth of communication technology that keeps developing, the way we obtain and provide information are developing. One of the applications that get lots of interest is Telegram. This application makes out communication easier. The development of communication model through Telegram is developing as well, one of the models is the chatbot. Chatbot can be made answers a lot faster. Until recently, chatbots are mostly created with a particular programming language. This makes creating a chatbot only limited to those who understand the programming language. Although many applications offer to create a chatbot without programming by big vendors, but there hasn’t been any academic literature for this topic yet. Therefore, in this research, I will design and implement the Telegram chatbot management system. This application provides to create a chatbot without programming language requirements. The user just needs to set the keyword and choose what action will chatbot give. This application also provides a direct message, broadcast message, and display usage statistics. This application tested by creating actions set, buttons set, command, direct message, broadcast message, and display usage statistics. The user can do all of those without any programming language requirements.
Current Voltage Analysis of High Voltage Plasma Discharge
Authors: Fadhillah R. , Anwar M. , Perdana Y. M. P. , Anjarwati L. , Apribowo C.H.B.
Published: March 2021

Nowadays plasma technology can be used in various types of sectors in everyday life. The development of research on plasma technology provides many benefits in every sector, like industrial for material processing, environment for waste treatment, etc. This research aims to see the current-voltage impact on plasma discharge using Inverter Boost Kit 15 kV as the source of plasma, to find the energy needed to produce plasma and the distance of electrodes when the plasma occurs. Sensors of current and voltage were installed simultaneously on each side to measure the values during plasma discharges. Mathematical calculations were also performed to determine the electric charge and capacitance values of plasma. As the result based on the secondary current value, the discharge type of plasma is corona discharge, because the values reach the order of microampere. The capacitance value temperature value increase when batteries supply higher current to the electric motor, while voltage is decreasing. The capacitance value affected when the discharge gap change. The average discharge gap value is 5 mm, and when the discharge gap increase, the capacitance value will decrease.
Recent Trends of Big Data in Precision Agriculture: a Review
Authors: Sourav A I , Emanuel A W R
Published: March 2021

Recent developments in the field of technology have led to a renewed interest in the field of smart agriculture. The current smart agricultural system produces and depends on large amounts of data, yet, it is hard to process the vast amounts of data using traditional data analysis systems. Big Data technologies have attracted much attention among researchers due to their potential to handle large amounts of data. Thus, for numerous possibilities and powerful data processing capabilities, Big Data continues to become a hot topic of research in the agricultural field. This is indicated by the existing several pilot projects as well as various investigations that have been performed in the Big Data area. Therefore, this study attempts to review the recent trends of Big Data technology in the field of precision agriculture. The research focuses on the latest applications of Big Data technology in multi-disciplinary agri-area domains. A total of 25 recently published studies about Big Data in agri-areas were selected for the review process after proper screening. The selected papers were categorized according to their fields of study, purposes, methods applied, as well as their contributions in the agri-field. The findings indicated that Big Data application areas are expanding, and the impacts are significant in precision agriculture.
Redesign Integrated Control System GTG and HRSG to Reduce Loss of Electrical Production at Combined Cycle Power Plant Muara Karang
Authors: Nurkholiq S , Putra R K , Khumaidi A , Fatimah F , Kusuma E
Published: March 2021

Combined Cycle Power Plant (CCPP) Block 1 Muara Karang control system had performance degradation since 2016-2017. Performance degradation comes from the complexity of the design architectures that are serially configured which can cause loss of electrical production. The Re-Design Method is able to simplify the architecture design by replacing hardware devices into modbus-based TCP-IP software that is compatible with the communication technology between GTG and HRSG and has a redundant path that can increase reliability. Based on the Muara Karang PLTGU Block 1 disturbance report data, redesign is able to increase reliability and better financial aspect. It shows that before the redesign there were 9 disruptions, while after the redesign there were no failures and Total saving opportunity loss of electrical production is Rp 10,792,782,094.30. This value is obtained from the unit repair time from operation failure and electricity sales price. On the corporate side, Re-Design can be applied to other generating units that have differences in technology based on open protocol.
Inlet Guide Vane Tracking Effectiveness at Various Compressor Efficiency of Gas Turbine
Authors: Purba O , Zhultriza F
Published: March 2021

The baseload operating patterns in Java-Bali’s system are imposed on coal-fired power plants, the combined cycle power plant (CCPP) is used as a spinning reserve so that the CCPP operates with a small load factor (partial load) to support system reliability. This operation results in a high plant heat rate for the CCPP since it operates more often at minimum loads. To improve the heat rate of CCPP at partial load, inlet guide vane tracking (IGVT) is performed. IGVT alters the opening position of inlet guide vane (IGV) in the partial load operation. The effect of IGVT application in CCPP is analysed with several operating parameters, such as fuel usage, turbine exhaust temperature (TET), the total load generated by the CCPP, and the total of net plant heat rate (NPHR) after IGVT application. The variation on IGV leads TET to increase. A higher TET affects the heat recovery steam generator (HRSG) and causes the load generated by the steam turbine to become larger compared to the load before performing IGVT application. The results show that the combined cycle heat rate drops to 24 kCal/kWh and thus improving the efficiency of the CCPP, up to 1.5% in partial load operation model.
Gas Turbine Hidden Capacity Recovery by Inlet Air Filter Variation Method to Produce Clean and Efficient Energy
Authors: Purba O. , Zhultriza F.
Published: March 2021

In the F-series gas turbine with the capacity of 250MW, as time goes by, the power produced will drop below its initial capacity, this refers as a hidden capacity. Hidden capacity occurs due to several causes, one of them is the decreased of compressor efficiency. This happens because the Inlet Air Filter (IAF) is unable to filter particles more than 10 µm, as a result particles infiltrate compressor which can prompt scaling on compressor blade. This paper will discuss an effort to recover the hidden capacity by varying air filtration system in the IAF. The variation of IAF use High Efficiency Particulate Air (HEPA) filter and combination of pre-filters, consist of bag filter and coalescer, which can filtrate particles less than 10 µm and 1 µm. By implement this modification, compressor efficiency remains at 90.1%, compared to existing IAF, compressor efficiency drop to 85% and continuously. Because the compressor efficiency is maintained, power plant efficiency can also be maintained to avoid heat rate drop by 40 kCal/kWh. As a summary, after modifying the IAF, the F-Series Gas Turbine can produce more reliable power capacity, thus, the gas turbine can produce maximum load efficiently and hidden capacity can be recovered.
Natural Frequency Evaluation of Last Stage Steam Turbine Blade Power Plant Using Finite Element Method
Authors: Kokong A M , Widjayanto T , Setiawan H , Laksana A R , Djunaedi I
Published: March 2021

The possibility of a power plant trip can disrupt the stability of the network frequency settings. Load shedding is done at the frequency level. In case of frequency under nominal setting, the load shedding or trip generator decision must pay attention to the generator equipment factor, especially the last stage turbine blade and lacing wire. In this study analysis modal using ANSYS 2019 R2 was carried out to determine natural frequency of the last stage blade LP (low pressure) Steam Turbine Tanjung Awar Awar Indonesia power plant when operating at low frequencies, which is below the nominal operating frequency of 50 HZ or at a rotation of 3000 rpm. The finite element method analysis is applied to the 1 blade and 5 blade systems. The result for a natural frequency of 1 blade system occurs at 2639.6, 2783 and 2915 rpm. For the 5 blades system, natural frequency occurs at 2648 and 2563 rpm, so it can be concluded that the setting under frequency is not in the range of natural frequency last stage LP turbine blade, and lacing wire damage is not triggered by the natural frequency steam turbine blade.
Indramayu 3 x 330 MW CFPP Coal Yard Management Optimization with K-Means Clustering
Authors: Andria S
Published: March 2021

Coal yard management is part of the generation management to ensure that coal supply to the unit can continue to be met. The coal entering the boiler is regulated considering various coal characteristics that differ between suppliers with coal mixing strategies, to ensure the generating unit works following the performance target. One of the generating units operated by PT Pembangkit Jawa Bali (PJB) is the Indramayu 3 x 330 MW coal-fired power plant (CFPP). Using 1507 data shipments of PLTU Indramayu from January 2017 to June 2020, a more straightforward coal yard management method can be analyzed. Data were analyzed using k-means clustering by using important parameters from coal property data. Important parameters used are Gross Caloric Value (GCV), Hardgrove Grindability Index (HGI), theoretical air for combustion, and slagging index. From the modeling with k-means clustering, the six optimal clusters are obtained. These six clusters are much simpler than before, managed in 16 clusters in the coal yard. Simplified coal yard management will have a significant impact on operational efficiency.
PT PJB UPHT Calibration Laboratory Business Strategy with Business Model Canvas Method
Authors: Ardiansyah I , Ariyanto A W
Published: March 2021

Industry in Indonesia is facing the Asean Economic Community (AEC), which came on January 1, 2016. AEC have 3 pillars, namely: metrology, standardization, and conformity assessment. These 3 pillars facilitate the flow of products to meet quality standards for ASEAN market. The product standardization process requires calibration and test laboratories spread throughout Indonesia. PT PJB through its maintenance unit, namely UPHT and UPHB, has tried to establish a calibration laboratory to meet the quality standard requirements. Firstly, the calibration laboratory serve the internal needs of PT PJB, but seeing market opportunities, it can become a profit center by reaching calibration market. So that the PT PJB UPHT Calibration Laboratory can become a new line of business, the calibration laboratory business is developed to produce a value proposition as a profit center for PT PJB in calibration services. Business development of calibration laboratory is carried out using the Business Model Canvas (BMC). Through SWOT analysis and Blue Ocean Strategy, 2 Alternative BMC will be developed. Using Minaut decision making analysis, business models selected is alternative BMC 1 to be implemented in first two years and alternative BMC 2 to be implemented in the next years.
Development of Reliability-Based Decision Making for Optimum Operation and Maintenance Strategy in Coal-Fired Power Plant
Authors: Akhsani M F , Yuniarto M N
Published: March 2021

Operation and Maintenance (O&M) held a significant factor in the power generation business. Despite the costs only about 15% of all life cycle costs, this figure may fluctuate to ± 20% due to spare part costs, equipment’s economic lifetime, and personnel cost. This paper describes a reliability-based Decision Support System (DSS) development to determine an optimum O&M strategy for coal-fired power plants. The methodology was developed from System Dynamics modeling, with the objective function to maximize Net Present Value (NPV) and maintain availability exceeding its goal. DSS allows users to study the power plant cost characteristics within their life cycle, including its sensitivity to NPV. The model was tested to a 600 MW coal-fired power plant in Indonesia. Mean Absolute Percentage Error (MAPE) applied as model acceptance criteria. From this study, coal price was the most sensitive variable to NPV (62.36%), followed by dispatcher demand (53.31%), and overhaul duration (1.5%). From 4 simulated scenarios, it was concluded that O&M outsourcing as asset operator authority was a proper choice that provides the highest NPV. Nevertheless, some risks related to employee competence and bureaucratic obstacles should be controlled.
Increasing the Number of Inductive Stove Users in Indonesia Using Cognitive Intervention Model to Support Industry 4.0 Implementation at PT PLN (Persero)
Authors: Ramadhan A S , Ulfa E A
Published: March 2021

Indonesian government electricity utility company, PT PLN (Persero) has applied the application towards Industry 4.0. One of its application is promoting inductive stove among households, in terms of modernizing Indonesian people’s life behaviour. Inductive stove users in Indonesia is still low, because of its bad quality of promotion. So, the authors will try to provide suggestions to improve the quality of inductive stove promotion using cognitive intervention methods. This method is expected to increase inductive stove users in the households sector by changing the mindset of the society by cognitive intervention method and supports PT PLN (Persero) to apply industry 4.0 in Indonesia especially for the households sector.
Study of Debris Filter Valve Opening Angle Adjustment for NPHR Improvement in Kaltim Teluk CFPP
Authors: Santoso A , Priyono A , Huda K
Published: March 2021

Many things can affect the Net Plant Heat Rate (NPHR) value, including operating parameters, fuel and equipment’s condition. The performance target of NPHR for Kaltim Teluk CFB CFPP based on specifications is 3430 kCal / kWh. Operational data shows that the NPHR of Unit #1 and Unit #2 is higher then the performance target. Analysis of operation and maintenance data showed that the low average net load and high condenser back pressure are the dominant problems that caused heat loss. One way to minimize heat loss and improve NPHR performance can be done by maximizing debris filter cleaning process through adjusting valve opening angle which can reduce differential pressure and finally reduce the backpressure at the condenser. With the flow simulation inside the debris filter, in order to achieve maximum flow rate with acceptable erosion rate, the optimum cleaning reached at valve opening angle 75°-60° and with this cleaning method, heat loss can be reduced 14.96 kCal/kWh and 50.09 kCal/kWh for unit #1 and unit #2 respectively.
Implementing Risk-Based Maintenance Strategies for Distributed Control System as Power Plant Asset Management
Authors: Yulianto D T , Isman R M , Ihsan S N , Susanto H G
Published: March 2021

The electricity generated from the power plant is subject to several requirements for active power, voltage, and frequency according to the grid system, so the machine must be controlled to achieve requirement by a power plant control system knows as Distributed Control System (DCS). DCS system in block 1 Muara Tawar power plant using Procontrol P-13 for gas turbine and Procontrol P-14 to control steam turbine. These systems had operated since 1997 and had been nearly operating for 23 years until now, and several failures tend to increase from time to time. The failures of the DCS and the lack of control cards will result in the loss of production. DCS system assets must handle properly to maintain the overall reliability of the power plant system. A method and strategy to maintain DCS must be carried out and ensure reliability and risk always under controlled conditions. Implementing Risk-based maintenance by carrying out quantitative calculations through the reliability approach and the level of the consequence of failure to calculate equipment risk is one of the methods of the DCS system. The result of Risk-based maintenance method shows the highest risk on risk map of the DCS system was in cubicle 14CBA02, 14CBA03 with a high-risk level and gas turbine and HRSG cubicle in medium-high level. The interval preventive maintenance time calculated by reliability within a year showed that cubicles 14CBA02 and 14CBA03 suggested to be maintenance every 29 days to reduce possibilities to failure.
Cavitation Draft Tube Analysis of Francis Turbine Loads Variations: A Case Study from Cirata Hydropower Plant
Authors: Sibuea R T , Mirmanto H
Published: March 2021

Hydropower plant (PLTA) is a power plant of EBT (Renewable Energy), which utilizes water as a primary energy source. PLTA has a very important role in balancing the stability of network systems. In improving network system stability, hydropower is operated in a wide load range, frequent start-stop, and varying loads. Other functions are also as a buffer of peak load and back up system in case of interference in the network system. Francis turbine is the most widely used turbine and has a maximum efficiency of 93-95%. Problems related to the operation of hydropower are operational instability, cavitation, vortex breakdown, pressure shocks, vibration and noise that sometimes cause turbine system failure. In relation to the above conditions then in this thesis will be studied how the occurrence of cavitation due to variations loading. Case study conducted in this research is at Cirata hydropower plant with capacity of 126 MW per unit, which has type Francis turbine vertical shaft (variation of load starts 40% and 100%). The research method is done numerically, with modeling and flow simulation using ANSYS CFX 18.2. The results of this study show that at 40% load-operating conditions there is a very low-pressure area (under vapor pressure) and the emergence of a vortex rope that causes cavitation in the draft tube area, especially in the elbow region. While at 100% load operating conditions only slightly visible low-pressure area and no vortex rope appears.
A Proposed Scheme and Future Development for Carbon Trading System in Indonesia based on Case Study in Muaratawar Add-On Power Plant
Authors: Adhiyoso A , Pardiansyah I , Akshinta P Y , Aryata I M
Published: March 2021

The growth of electricity demand in Indonesia has enforced the government to develop several large-scale power plants to electrify some region. Due to economical and operational aspects, mostly majority of plants are build based on coal-fired plant, where it can give bad impact to environment. Furthermore, some mitigation has been taken into account in attempt to reduce the GHC emissions. One of the options is by evaluating on a case in Muaratawar add-on project (Block 2, 3 and 4). The addition of HRSG at the plant is expected to reduce the GHG emissions to 0.48 Tons of CO2/MWh with a potential carbon reduction of 3.599.410.69 Tons of CO2/year. This paper concern on proposed business scheme for carbon trading through a comprehensive evaluation based on historical recorded data and baseline along with weighting and scoring method to select the best carbon trading system.
Study on PV System Development at UP Brantas for Hydroelectric Power Plant Station Service Supply
Authors: Irwan
Published: March 2021

Concern toward the preservation of natural resources became one of the attention for the generation industry in Indonesia. Thus the development of renewable energy in the generation sector is important. Several hydropower plants of UP Brantas have the potential to develop PV systems in the Kolam Tando Harian (KTH) and the tailrace area. The hydropower as the object of this study, the average needed for the hydropower electricity station service per year can be calculated by calculating the PV system with 5% - 80% of the potential area that has been determined. Due to the station service costs of hydroelectric power stations increases at 0.172 $/kWH, the development of PV systems is an alternative solution to reduce the cost of hydropower station service. Refers to the capital cost of PV & energy storage issued by Lazard in 2019, it is known that the LCOE value for PV development in UP Brantas hydropower ranges between 0.11 - 0.21 $/kWH. Compared to the import energy tariff of 0.172 $/kWH, the development of this PV plant is potential and realistic to implement. This program is aligned with government and company policies in realizing the strategic goals of renewable energy development. The development of this PV plant can be integrated later into the hydropower load center using a hybrid decentralized grid-connected PV system configuration with or without battery energy storage.
Analysis of Muara Tawar CCPP Block 1 Steam Turbine Vibration
Authors: Hidayat Asnawadi , Firmansyah Iman , Wasiwitono Unggul
Published: March 2021

Condition monitoring of steam turbine enables early detection of faults and avoid unexpected breakdowns. Vibration analysis has gained much attention in the field of condition monitoring because of its accuracy in detecting faults and its ability for proper diagnosis of the faults. Muara Tawar CCPP block 1 has a steam turbine generator with a capacity of 215 MW. Steam turbine roll after inspection shows high vibration occurs on bearing 1. This study aims to find the cause of this high vibration and provide recommendations to avoids such symptoms. The vibration data used in the analysis are obtained from vibration analyzer tools associated with vibration monitoring systems. It is found that the amplitude of vibration at rotational speed frequency (1X) increased and phase angle changes at a constant speed. The vibration level at the coast down is higher than the observed vibration level at run-up. There is a shift in the position of critical speed which indicates a change of rotor stiffness. It is concluded that the high vibration is likely by a thermal bow on the rotor. The thermal rotor bow is caused by a light partial rubbing between rotor and labyrinth seal on the stator.
Collaboration Holistic Enterprise Architecture and Asset Management System for Power Generation
Authors: Setiyowati Rianti , Zemmy M , Agung P J
Published: March 2021

Asset Management becomes the most important part of managing power generation sector. It will determine the success of efficiency and effectiveness as well as the economic value of an electric product that produced. Many power generation unit that must be managed and implementing asset management system according to the standard ISO 55001, the company no longer can not only focus on the operational terms but shifted to the strategic, where management is asked to be able to see the company in a holistic view and faster in making decisions. In this journal the authors convey the development done through the collaboration of Enterprise Architecture (EA) which is the blueprint of the organization that integrate between processes, data, applications and technology and asset management of the company as well as adding seven dimensions of performance indicators in one worksheet and linkage different from other EA through the development of application platform to digitalize the needs of the company in managing the asset that we called PJB-IMS 2.0, this concept can be a prototype for other generating company in implementing asset management system. The existence of EA realized in PJB IMS 2.0 is ensured to be in accordance with the challenges future business that increasingly complex.