Iwa Garniwa | Universitas Indonesia 5 (original) (raw)

Papers by Iwa Garniwa

2017 15th International Conference on Quality in Research (QiR) : International Symposium on Electrical and Computer Engineering, 2017

This paper proposes an approach for development of electrical system. The proposed approach is co... more This paper proposes an approach for development of electrical system. The proposed approach is combination of principal component analysis (PCA) and cluster analysis. This research based on relevant data of total population, gross domestic regional product (GDRP), GDRP of industry, GDRP of business, electric power each customer and energy used for each sector. This development profile is set up to show the condition of electrical system of each region, that will be used to support policy development electrical system of spatial development in the future. This paper considers 24 regions in South Sulawesi province as development center points and use principal component analysis (PCA) to assess the regional profile for development. Cluster analysis is used to group these region into clusters according to the new variable produced PCA. The general planning of electrical system of South Sulawesi province can provide support for policy making of electrical system development. The future will include add on research several variables.

2021 3rd International Conference on High Voltage Engineering and Power Systems (ICHVEPS), 2021

Tinggi Island is located off the South Bangka Regency coast, with an electricity peak load of 7,5... more Tinggi Island is located off the South Bangka Regency coast, with an electricity peak load of 7,5 kW supplied by the 40 kW diesel power plant. One of the problems in the provision of electricity in Tinggi island is difficulty in delivering fuel process. This problem causes expensive fuel prices and a limited amount of fuel. This research aims to analyze the technical and financial of a hybrid 16 kW biomass power plant with the existing diesel power plant. The method used in this research is to estimate the energy generated by the diesel and biomass power plant, the fuel required, and the payback period by calculation. From the study, the diesel power plant will produce 1,999.53 kWh of electricity per month with the need for diesel oil of 1,939 liters. Meanwhile, the biomass power plant will produce 2,077.53 kWh of electricity per month with a biomass requirement of 2,078 kg. Based on financial analysis, waste pellets, risk husk, and wood charcoal as biomass power plant’s fuel have good feasibility with a payback period between 1.9-2.6 years. In contrast to the three types of biomass, palm shells are not economically feasible to use as fuel because they are more expensive than diesel fuel.

Proceedings of the Proceedings of the 1st International Conference on Environmental Science and Sustainable Development, ICESSD 2019, 22-23 October 2019, Jakarta, Indonesia, 2020

Recently, electricity consumption in Indonesia continue to increase rapidly along with the increa... more Recently, electricity consumption in Indonesia continue to increase rapidly along with the increase in technology, economic growth and also the increase in the population. One potential source of electrical energy comes from geothermal energy, where Indonesia has enormous potential. In this research the aspects studied is sustainable development on economic and social as research variable, where the existence of geothermal power plants is expected to have a positive impact on the sustainability of economic and social of the surrounding communities. Locus of this research is Geothermal Power Plant that operated at Kalapanunggal sub-district, which is located in Sukabumi District, West Java. The method used is Analytical Hierarchy Process (AHP) to obtain assessment criteria. From the AHP results, the economic criteria from existence geothermal power plant is regional income from production bonus, and social criteria is the use of labour and local products.

Proceedings of the Proceedings of the 1st International Conference on Environmental Science and Sustainable Development, ICESSD 2019, 22-23 October 2019, Jakarta, Indonesia, 2020

Coal fired power plant (CFPP) capacity in Indonesia continues to grow, that also increase the amo... more Coal fired power plant (CFPP) capacity in Indonesia continues to grow, that also increase the amount of fly ash and bottom ash (FABA) waste produced from the CFPP. The FABA waste can be used as a mixture of cement in infrastructure development. The management of FABA waste is currently 70% utilized by the cement industry for activities located outside the power plant region, so that additional transportation costs are needed for the management of the waste. How to systematically organize institutional infrastructure and physical infrastructure to sustain recycling mechanisms or waste management is the problem. This research has an objective to find out the aspect of waste management system that could increase the usage of FABA to support cost of raw material efficiency in infrastructures. The method to find this research objective is using the sequential mixed methods. A monitoring system for the establishment and utilization of FABA waste can be built to improve waste utilization, prevent environmental and cost impacts due to further waste travel, then build the 'sound material cycle society' to promote FABA as raw material.

International Journal of Energy and Environmental Engineering, 2019

Under a condition of sunlight exposure, the temperature of a parked car's cabin will increase gra... more Under a condition of sunlight exposure, the temperature of a parked car's cabin will increase gradually. Compared to the ambient temperature, the inside and outside temperature will be different, which will be favourable for thermoelectric generators. This study investigated the temperature distribution pattern of a car parked in the direct sun using real and model cars. Performing different scenarios, we found that the car model equipped with a fan and a dimmer was the suitable approach to the real car model. Compared to the ambient temperature, results for both the real car and the model car indicated that heat rose drastically inside the car cabin. The calculation using the thermoelectric generator eTEG HV37 considerably could generate up to 6.9 mW per module. Therefore, by having a thermoelectric generator installed on an area of 1 m 2 of the car roof, 280 W power could be generated.

2015 International Conference on Quality in Research (QiR), 2015

In the power generation, transmission or distribution of electricity, transformer is one of the m... more In the power generation, transmission or distribution of electricity, transformer is one of the most valuable and important asset. The transformer reliability is very dependent on the quality of the insulation system. During the operational phase transformer, transformer oil will undergo degradation or deterioration due to high temperatures and chemical reactions that occur as oxidation. Aging in insulating oils would also affect its characteristics, such as physical and electrical properties, as well as lowering the lifetime of the insulation. This paper discusses the aging of insulation oil. Research on accelerated thermal aging was conducted to determine the behavior of insulating oil deterioration Nynas Nytro 10X and predict future use. Based on the Arrhenius law, if the temperature of transformer oil samples were operating normally in 60°C, the lifetime prediction of insulating oil will be 697.079 hours. Furthermore, the percentage decrease in the lifetime prediction isolation transformer IBT CBN S phase at normal loading conditions, the imposition of emergency at long time, as well as the emergency at short time in a row at 0.002032%, 0.047435% and 0.957268% of the rest period normal to the insulation of 5.5 years.

2019 International Conference on Mechatronics, Robotics and Systems Engineering (MoRSE)

Nowadays the global utilization of solar energy for electricity generation has greatly increased.... more Nowadays the global utilization of solar energy for electricity generation has greatly increased. But the amount is still very small compared to the other existing potentials. The classic issue in the utilization of solar energy is intermittent solar energy and power fluctuations. The power of the PV is not fixed, unpredictable and dependent on natural factors, namely irradiation, temperature and the influence of shadows. Several methods have been proposed to overcome intermittent energy and fluctuations in PV power including the Hybrid PV Generators, Power Curtailment, Geographical Dispersed, and Electrical Storage methods. Each method has characteristics in its application. Hybrid PV generators are relatively easy to apply but they are expensive and cause greenhouse gases. Power Curtailment is easy to apply but it is inefficient because a lot of energy is wasted. Geographical Dispersed requires large land. Electrical storage requires a large energy storage capacity. To overcome this, a new method is proposed, namely Dynamic Power Injection which is a combination of MPPT, Power Curtailment, and Electrical Storage. A comparative study with simulation using Simulink Matlab against 3 methods of PV power stabilization was conducted. The simulation results show that the DPI method is the most effective and efficient way to increase the stability of PV power.

2019 International Conference on Sustainable Energy Engineering and Application (ICSEEA)

The use of PV for harvesting solar energy as electrical energy has been done globally. On a large... more The use of PV for harvesting solar energy as electrical energy has been done globally. On a large scale PV is connected to the distribution as a peak load generator during the day. Integration of PV with grid has several issues, especially because of the intermittent solar energy problems due to the influence of irradiance and environmental temperature. It’s causes the energy produced to fluctuate and be unstable. These power fluctuations affect system stability and frequency. To overcome this problem, several methods for PV power stabilization have been developed. One of them is Constant Power Generation (CPG) where PV output power is limited to certain P value settings so as to reduce PV power fluctuations. In this paper the Dynamic Power Injection method is proposed which is a modification of the CPG method with the dynamic action of charge and discharge using batteries as energy storage. The principle of DPI is same with CPG that determines P setting as P output of PV Power, but stabilization of PV Power Outputis also support by active power management. Charge when PV power bigger than P setting and injection when PV power less than P setting. Thus the output power in each condition of PV power same with P setting. By using matlab simulink a DPI circuit simulation is carried out to increase the stability of the power and frequency of the system. The simulation results show that DPI is able to produce stable PV output power on 30 kW and the frequency of the system can be maintained at 50 Hz.

2019 International Conference on Sustainable Energy Engineering and Application (ICSEEA)

One of the challenges of photovoltaic (PV) is the instability of PV output power. This is caused ... more One of the challenges of photovoltaic (PV) is the instability of PV output power. This is caused by fluctuating of solar radiation falling on the surface of the PV module. For the PV scheme on Grid, power instability causes instability of the power system. Several methods have been developed to stabilize PV power including constant power generation (CPG), hybrid PV-generators and power smoothing. But there are still flaws in the method. In this paper, the Dynamic Power Injection (DPI) method is proposed to stabilize PV output power. DPI is a combination of the CPG method with energy storage. The DPI stabilizes PV output power according to the predetermined setting power. Thus, PV output power can be kept constant without being affected by changes in load power. To obtain stable PV output power, the DPI performs two work functions, namely the CPG function by limiting PV power according to its power setting and the action of storage energy by absorbing excess power and active power shortage injection. The DPI module is designed by using the Arduino Mega microcontroller which is supported by voltage and current sensors and batteries as energy storage. The operation the DPI module works is by reading the parameters of incoming power, output power, and battery power. Then the output power is compared with the predetermined setting power. Based on the results of testing, the output power is almost close to the setting power with an error rate of 6.46%, however DPI can function properly to stabilize the output power with constant power by predetermined settings.

2021 IEEE 4th International Conference on Power and Energy Applications (ICPEA)

Remote areas in the Indonesia archipelago are mostly isolated from the utility grid and powered b... more Remote areas in the Indonesia archipelago are mostly isolated from the utility grid and powered by expensively known diesel generators. Due to the limited access and transportation system, the diesel fuel price can be very high. Therefore, the power can only be served to 1.83% of the population, and worse, these customers are not even fully electrified in 24-hours. This research presents Hybrid Renewable Energy System (HRES) design in the isolated grids in Indonesia. The HRES consists of the existing diesel generators with the solar PV system and Battery Energy Storage System (BESS). The optimized design of HRES is obtained following two objectives, such as the lowest generation cost and highest number of customers served. The HRES is implemented in one isolated grid in Indonesia, and the design is validated using HOMER software. The result shows that the implementation of HRES can reduce the generation cost by 50% and increase the electrification to 7.6%.

2021 IEEE 4th International Conference on Power and Energy Applications (ICPEA)

The current dynamic tariff has become a trend in developing countries, especially in the electric... more The current dynamic tariff has become a trend in developing countries, especially in the electricity sector. Flat tariff on electricity costumers causes the cost of electricity to be less optimal. In Indonesia, the second highest costumer group after industry is residential customer, who has 37,6 % of total electrical energy consumption. So naturally the load curve tends to approach the curve of residential needs. In the Java Madura Bali system, the peak load of a residential customer occurs at the same time as the peak load on the system. If load shifting scheme of the electrical energy consumption of the residential customer can be applied, it will give a big impact on the system. The peak load is borne by the power plants which generally have expensive operational costs. By the reduction of peak load using load shifting scheme, a significant increase of system efficiency will be obtained. This paper develops a method of determination of a dynamic tariff combination scheme, Time of Use (TOU) and Critical Peak Pricing (CPP) based on revenue neutrality. The scheme is simulated to residential customers in the Java Bali Madura system. From several scenarios, the results of the implementation of this scheme show the increasing of the total cost efficiency of electricity supply in the Java Madura Bali system.

2019 6th International Conference on Information Technology, Computer and Electrical Engineering (ICITACEE), 2019

The utilization of solar energy for electricity generation is increasing. But, because of the fac... more The utilization of solar energy for electricity generation is increasing. But, because of the factor of the intermittent irradiance and ambient temperature so that the energy produced fluctuates and unstable. For PV connected to the grid, these power fluctuations affect system stability and frequency. To overcome this problem, several methods for PV power stabilization have been developed. One of them is the Constant Power Generation, where PV output power is limited to a certain power value so it can reduce PV power fluctuations. In this paper, the Dynamic Power Injection method is proposed as modification of the CPG method with energy storage batteries. In principle DPI similar with the CPG method that determines the power limit, but DPI operation include the active power management by charging and discharging action. The battery is using as energy storage when Power PV greater Power limit. On the other hand battery as an energy source for active power injection at Power PV less than Power limit. Thus the output power in each condition can be maintained as Power PV equal with P limit. In this research, DPI modules are built on Arduino controller-based and monitored with the thingspeak webserver. The experimental results of DPI can stabilize PV power fluctuation at it's setting power with an error of 5% and a 15-second time delay.

Opción: Revista de Ciencias Humanas y Sociales, 2020

2018 International Conference on Sustainable Energy Engineering and Application (ICSEEA), 2018

Currently solar photovoltaic that is integrated into the gridhas significantly increased the capa... more Currently solar photovoltaic that is integrated into the gridhas significantly increased the capacity. High photovoltaic penetration on the grid has an effect on the reliability and stability system. This is due to the nature of the fluctuative photovoltaic generation. This paper analyzed the effect of fluctuative photovoltaic generation on system frequency and determined the maximum level of photovoltaic penetration integrated to a 20 kV distribution grid which is in accordance with Indonesian grid code. A matlab simulink is used to simulate the solar photovoltaic integrated into the distribution grid which the photovoltaic penetration are varied to be 25%., 20%., 15% and 10% of peak load. In this simulation., the photovoltaic plant is not equipped by energy storage system that aim to see the frequency response system naturally. One of the grid code that must be complied is to keep the frequency system in the range of 47.5 to 52 Hz. Based on the simulation., photovoltaic penetration of 25% results the lowest frequency of 46.6 Hz so that the penetration is not permitted to integrate into the grid. While the maximum level of photovoltaic penetration that might be allowed to integrate is 20% which results in the lowest frequency of 48 Hz.

2018 International Conference on Electrical Engineering and Computer Science (ICECOS), 2018

This study analyses the feasibility of the Sea floating PV (SFPV) system utilization in conjuncti... more This study analyses the feasibility of the Sea floating PV (SFPV) system utilization in conjunction with Diesel generator (DG) to supply the resorts at Small Kei Island, Southeast Moluccas, Indonesia. The SFPV system uses off-grid scheme with a specific scenario that is by dividing the battery into three equal parts which are used interchangeably in order to reduce the fluctuation of the output power generated by DG at once to meet the daily load requirement for 24 hours. The impact is the battery charge cycle changed to twice in three days, thus the battery life will increase to 1.5 times longer. In this study, the economic analysis is done with the loan interest of 10% and the operating time for 25 years. With electricity tariff of 1 USD/kWh obtained the most feasible and profitable combination of capacity of DG and SFPV systems is 130 kW and 20 kW respectively. The combination yields the duration of PBP for 9 years 0 months and 9 days, NPV of 36,545 USD, IRR is 11.65%, and PI ratio is 1.016.

2017 International Conference on High Voltage Engineering and Power Systems (ICHVEPS), 2017

Indonesia, being one of the world's biggest producer of palm oil, has the potential to utiliz... more Indonesia, being one of the world's biggest producer of palm oil, has the potential to utilize palm oil as a replacement for fossil fuel. However, palm oil possesses a high level of viscosity. A heater system is needed to reduce the viscosity of palm oil as well as switching of fuel channel between diesel oil and mixed oil (palm oil and diesel oil). The purpose of this study is to design an automatic heating system for use on a small-scale diesel power plant. The automatic heating and switching system consist of a heater element, microcontroller, temperature sensor, relay and solenoid valve. This system read the temperature of mixed oil. If the temperature of mixed oil is below the temperature limit that is specified on the microcontroller then the heater will turn on and the solenoid valve will allow the diesel to flow to the engine. On the other hand, if the temperature of mixed oil is above the temperature limit that is specified on the microcontroller then the heater will turn on and the solenoid valve will allow the mixed oil to flow to the engine. The result of this study is this system can maintain a stable mixed oil temperature in the range specified on the program executed by the microcontroller with a low deviation value. The performance analysis of this study hopefully can be a reference for future studies on the usage of automatic mixed oil heater for small-scale diesel power plant.

Technology and Economics of Smart Grids and Sustainable Energy, 2021

Energy is an inseparable component in human life in every aspect. However, many regions cannot ut... more Energy is an inseparable component in human life in every aspect. However, many regions cannot utilize energy sources to support their daily activities, so there are several breakthroughs made by the government, including the construction of solar power plants in remote areas. Some challenges arise because is Solar Power in remote areas sustainable? This research analyzes the sustainability of Solar Power in remote areas as environmentally friendly energy built by government funds (State Budget). The research location is in Sukarasa Village, Bogor, Indonesia, a remote area that has Solar Power as a source of community energy. The analysis was carried out by analyzing the Solar Power sustainability factors such as technical, environmental, social, and economic factors). The results of the analysis of Solar Power sustainability in rural areas using the or Multi-Dimensional Scaling (MDS) method in the form of a kite diagram. Of the four dimensions of sustainability, the highest sustainability index values are the environmental dimension; social dimension; technical dimension, and economic dimension of having a less sustainable status, while the environmental dimension is the only dimension of sustainability that has a fairly sustainable status. These results indicate that solar power plants in remote areas are quite sustainable, but there needs to be a mechanism for periodic maintenance and community participation in managing this Solar Power.

IEEE Transactions on Dielectrics and Electrical Insulation, 2020

In this study, 238 power transformers (PTs) with operating voltages between 150500 kV and capaci... more In this study, 238 power transformers (PTs) with operating voltages between 150500 kV and capacities in the range of 60–167 MVA are tested for partial discharge (PD). Thirty-eight of the PTs exceeded the pre-determined value of 70 pC at 1.5 maximum voltage of the PT. Failure analysis of the failed 38 PTs showed that 21% of the PD sources originate from the winding cylinder, which is formed by bonding the edges of a pressboard with an adhesive. Therefore, in this study, the effect of casein- and polyvinyl-based adhesives used in winding cylinders was investigated through standard PD measurements. The results indicate that pressboards bonded with casein-based adhesives exhibit PD values 20–25 pC lower than those bonded with polyvinyl-based adhesives (50–400 pC) at identical applied voltages (7.5–25 kV or 3–10 kV/mm). The excellent performance of casein-based adhesives is mainly attributed to its porous structure, which accelerates the impregnation of oil into the adhesive and pressboard, as revealed by scanning electron microscopy observations. This practical study will be beneficial in the process of designing and manufacturing PTs and highlight materials for producing PTs with low PD values.