31 research outputs found

    A Design of a 345-kV Electric Power Transmission Line Interlinking Ramu and Rouna Grids in Papua New Guinea

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    According to PNG Power Limited (PPL), Papua New Guinea’s peak power demand is expected to increase from 210 MW in 2012 to 347 MW in 2026. Under the current state of the power sector in Papua New Guinea (PNG), it is critical to implement measures to cope with the increasing power demand to promote investment, economic growth, and ultimately to achieve poverty reduction through economic growth. One of the solutions identified to improve the reliability of PNG power systems and thus to meet the demand is to interconnect the major grids in the country so that the loads could be shared among them. This project embarks in designing a 345-kV electric power transmission line to interlink the Ramu and Rouna power grids of Papua New Guinea. The design is done by analysing all the necessary aspects of the transmission lines with in-depth calculations performed using MATHCAD software. This design is the basis for extra-high voltage (EHV) transmission network in anticipation for the power generation and demand growth in PNG

    Design of Broadband Dual-Frequency Microstrip Patch Antenna with Modified Sierpinski Fractal Geometry

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    Fractal antennas have the characteristic of radiating in multiple frequencies through the property of self similarity that fractal shapes possess. By connecting fractal shaped antennas, wideband coverage can be achieved. Microstrip patch antennas with Sierpinski fractal geometry can be tuned, by design, to work exactly at the bands of interest, through judicious choice of the fractal designs and iteration. Therefore, a broadband dual-frequency microstrip patch antenna with modified Sierpienski fractal geometry is designed by using Microwave Office 2002 simulation software. The broadband and multiple frequency characteristics of fractal antennas will be demonstrated. The performance of microstrip patch antenna with the classic and modified Sierpinski fractal geometries will be presente

    Physical properties of soil in the early stage of an agroforestry system in the High Andean zone

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    In Nariño, Colombia, land use has generated some problems such as erosion, compaction, lack of fertility, among others, so it is necessary to search for alternatives to mitigate these impacts. The objective of this study was to evaluate some physical properties of the soil in an agroforest system with Morella pubescens (Humb. & Bonpl. ex Willd.) Wilbur with Smallanthussonchifolius (Poepp.) H.Rob, in the experimental farm of Botana, in the city of Pasto, Nariño, where the bulk density, real density, total porosity, structural stability properties and distribution of aggregates were analyzed. The datas were obtained in two phases: f1 and f2 before and after agroforestry system implementation, respectively. A randomized complete block design with three treatments and three replications were used. The treatments corresponded to plant densities, T1: S sonchifoliuos, sowed to 1x1m, T2:0.8x0.8m y T3:0.5x0.5m, with three replications. M pusescens was stablished to 4x4m between plants and 9 m between rows and the control (f1). The statistics have differences between f1 (control) and f2 (treatments), to the structural stability properties and distribution of aggregates. The ground suffered a structural stability change to stable lightly (0.97 D.P.M) in f1 to a stable moderate (2.53 D.P.M), in f2. The distribution of aggregates passed to 60% in f1 to 70.3% in f2, with a media aggregation status. The different agroforest systems management could help, in the long term, by improving the structure of the ground through the vegetal material of arboreal component, the application of a minimum farming and the addition of organic matter

    Micro-Hydro/Solar Hybrid System Framework for Off-Grid Application

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    This paper introduces the conceptual system design of micro-hydro/solar hybrid system for Kampung Semulong Ulu, Sri Aman, Sarawak. Currently, Kampung Semulong Ulu is powered by solar and diesel-generator energy systems. The existing solar system generates less than 160 W for each door of the longhouse. With the completion of micro-hydro system along with the existing solar panel in the village, the community is hoping to get the proper and continuous power generation. Community in Kampung Semulong Ulu is facing difficulties since solar is only available for a limited period and yield electricity within a limited range of load. On the other hand, the running cost of diesel-generator is very expensive and unaffordable. However, even with the existence of power generated by micro-hydro system, better utilization of the energy produced is still of vital importance due to the fact that the amount of energy generated is limited. Therefore, the conceptual system design of the hydro-solar system integration is presented. The proposed system is to ensure that the energy produced will be well-distributed and at the same time, both systems must be utilized sufficiently to ensure their sustainability. In overall, this paper presents the micro-hydro/solar hybrid system framework for off-grid application toward the community in Kampung Semulong Ulu

    A Review of Sarawak Off-Grid Renewable Energy Potential and Challenges

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    Sarawak is the largest state in Malaysia, in spite of this, the population of Sarawak is relatively small and 42 percent of that population residing in the rural areas. Consequently, the Sarawak government is facing immense challenges in providing basic need such as electricity to the entire state due to the remoteness and small sizes of these settlements. Although the state produces sufficient amount of power, the cost of connecting these rural and non-rural small settlements to the grid is just impractical. The current energy scenario in Sarawak will be reviewed with a focus on the two reliable renewable energy resources currently being pursued by the Local Electrical Authority (LEA) for rural electrification projects which are the Hydro Power and Solar Energy. The paper will address the technical and localized challenges facing the micro-hydro and solar electric energy generation in Sarawak. The micro hydropower potential in Sarawak is estimated at 10.2MW but is not being fully developed due to difficulty in distinctive design and implementation which requires full participation and support from the local community to make it more economically viable and functionality in long run. In addition, Sarawak also receives a daily solar irradiation of more than 5 KWh/m2 throughout the year and that means huge potential for it to thrive. But design and implementation must be done carefully due to the tropical climate and operating temperature of the components. Ultimately, both renewable energy systems require trained personnel to attend to and involvement of LEA or any appointed agency to provide assistance and coordination are necessary to ensure greater success in rural electrification projects

    Fabrication of single chamber microbial fuel cell (SMFC) using soil as a substrate

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    This paper presents a Single-chamber Microbial Fuel Cell (SMFC) design by utilizing soil as a substrate with two sets of electrode combinations, which are graphite-activated carbon and copper-zinc of different sizes. It was found that graphite and activated carbon produced greater power density compared to copper and zinc. Moreover, it was observed that the graphite-activated carbon cloth electrode with a bigger surface area of 51cm2 resulted in a higher power density of 904mW/m2. To further improve the voltage production of this model, four SMFCs were stacked in series and connected to a DC-DC boost converter to increase the voltage to 1.482 V for the copper-zinc electrode and 1.722 V for the graphite-activated carbon electrode, respectively, which was sufficient to light up an LED light

    Bioelectricity generation from bamboo leaves waste in a double chambered microbial fuel cell

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    This study investigated the utilization of bamboo leaf waste and two varieties of bacterial sources, chicken manure and effective microorganism, in a microbial fuel cell (MFC) at three substrate concentrations (40 g/liter, 80 g/liter, and 160 g/liter). The primary objective was to investigate the kinetics of bacterial growth at various substrate concentrations in the MFC, as well as the effect of light conditions and pH on MFC power generation. The MFC had dual chambers with graphite electrodes serving as the cathode and anode. Within 72 h, the highest power density of 90.05 mV was attained using the highest substrate concentration of bamboo leaf waste and chicken manure during the logarithmic growth phase, albeit with a shorter duration. The longest sustained phase of bacterial activity was observed during the stationary phase, at the highest substrate concentration of 160 g/liter, followed by 80 g/liter and 40 g/liter. These results indicate that the logarithmic phase is the optimal time for bacterial activity in the MFC. However, attaining long-term stability in power generation in the logarithmic phase requires careful parameter optimization

    Bioelectricity Generation from Bamboo Leaves Waste in a Double Chambered Microbial Fuel Cell = (Penjanaan Bioelektrik daripada Sisa Daun Buluh dalam Sel Bahan Api Mikrob Dua Kebuk)

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    This study investigated the utilization of bamboo leaf waste and two varieties of bacterial sources, chicken manure and effective microorganism, in a microbial fuel cell (MFC) at three substrate concentrations (40 g/liter, 80 g/liter, and 160 g/liter). The primary objective was to investigate the kinetics of bacterial growth at various substrate concentrations in the MFC, as well as the effect of light conditions and pH on MFC power generation. The MFC had dual chambers with graphite electrodes serving as the cathode and anode. Within 72 h, the highest power density of 90.05 mV was attained using the highest substrate concentration of bamboo leaf waste and chicken manure during the logarithmic growth phase, albeit with a shorter duration. The longest sustained phase of bacterial activity was observed during the stationary phase, at the highest substrate concentration of 160 g/liter, followed by 80 g/liter and 40 g/liter. These results indicate that the logarithmic phase is the optimal time for bacterial activity in the MFC. However, attaining long-term stability in power generation in the logarithmic phase requires careful parameter optimization

    Bioelectricity Generation of Coconut Waste -based Double Chamber Microbial Fuel Cell with Various Substrate Compositions

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    The aim of this study was to investigate the generation of electricity in a microbial fuel cell (MFC) using coconut waste as substrate with various compositions. Different types of substrate with different pH values were tested in dual-chamber MFC. The maximum voltage level reached 699mV under alkaline condition after day 7th, which was considerably higher than those previously reported in literature using solid waste substrates. The series connection of the coconut waste MFC with boost converter module showed the ability to light up the bulb. Our results showed that implementation of local organic waste was promising in fabricating MFC for home appliances

    The Implementation and Calibration a Low Cost Propeller Type Current Meter in the Laboratory

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    Propeller type current meter or horizontal-axis rotor meters is an equipment that is used to estimate flow velocity in various fluids such as air, water, and oil. Several standard propeller-type current meters had been produced by companies are to cater to the demands, but these products are costly and limited in accuracy of the real-time during data recording. The design and implementation of the proposed propeller-type current meter are for river or stream application and thus, the Velocity-area method was used. The current meter was implemented by manipulating mechanical performance which is more reliable and stable in measurement. The propeller type current meters are compact with Analogue to Digital Converter (ADC) that is embedded in the microprocessor board for data processing. Meanwhile, the Real-Time Clock (RTC) module is used to maintain the accuracy of the real-time during data recording via Security Digital (SD) card and rechargeable Li-Po battery with DC/DC converter for power supply. The cost to build the propeller-type current meter is 44.95% cheaper than a commercial current meter. The testing and calibration process were conducted at the laboratory. The propeller-type current meter is tested in an 8-meter-long Flow Channel that varied from 0.3 m/s to 0.6 m/s and the result shows an average error is 1.0%. Therefore, the device shows an acceptable error and extremely useful to reduce research or operation costs
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