Journal of Engineering and Technological Sciences
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Design of True Hybrid Solar Wind Turbine for Smaller Hybrid Renewable Energy Power Plants
Get PDFContemporary hybrid solar-wind farms are commonly implemented using separate solar photovoltaic (PV) cell arrays and wind turbines, where the electricity currents generated from both devices are combined. However, this solution requires a large amount of space to cater for the PV arrays and wind turbines of the system. This paper proposes a new type of renewable energy electric generator with a small power production footprint (PPF) that allows reduction of land usage. The True Hybrid Wind-Solar (THWS) generator allows for the solar panels to rotate along with a VAWT wind turbine that is attached through a specially designed electromechanical coupling mechanism. The working principle behind the connections is described in this paper. The design of a hybrid circuit module that serves to combine the currents generated via the solar cells and the wind generator and also to automatically disconnect inactive wind or solar generators is described. The latter is important in order to eliminate unwanted load generated from the inactive generators within the THWS itself
Layer Stripping in Magnetotellurics (MT) for Enhancement of Resistivity Change Effect in Reservoir: Equivalence Analysis
Get PDFMagnetotellurics (MT) can be applied to monitor resistivity change at depth that is for example due to fluid injection in enhanced oil recovery or CO2 storage. The observed MT data changes at the surface may be insignificant, but the effect can be enhanced using the layer stripping method, i.e. calculating MT data changes that would be observed at depth based on data from the surface. Two well-known formulas for MT 1D forward modeling were reformulated to allow for calculation of the impedance at depth based on the impedance at the surface. We applied the layer stripping technique to synthetic data associated with models that were representative of a likely CO2 storage site. We also used an equivalent model and the Monte Carlo approach to estimate the sensitivity of the method to cope with the uncertainty of the host model and the input data. The layer stripping calculation has the greatest uncertainty at short periods, where the real and imaginary parts of the complex impedance tend to be equal, i.e. an homogeneous medium response. The layer stripping technique should be used with great caution based on a relatively precise 1D host model
Extreme Significant Wave Height of Western and Central Indonesian Seas and Its Correlation with ISO 19901-1:2015
Get PDFExtreme significant wave height is a commonly used parameter for designing offshore structures. ISO provides general extreme significant wave height information of six ocean regions in the world, including the Southern East Asian Sea. However, for the case of Indonesia, ISO only includes the Natuna Sea region. One of the qualified datasets that provide significant wave height data for Indonesian seas is SEAFINE by Oceanweather, Inc. This dataset covers the western and middle part of Indonesia. We analyzed the SEAFINE significant wave height hindcast data in these regions to obtain the extreme values. Extreme significant wave height maps were then produced based on the analyzed data. For the purpose of validation, we compared the extreme value analysis result with ISO 19901-1:2015 in regions where SEAFINE and ISO data intersect. The comparison showed that the analysis result tends to give approximately 25% lower wave height for a 1-year return period compared to ISO 19901-1:2015 but agreement for a 100-year return period. The SEAFINE analysis result also shows agreement with previous studies in the Karimata Strait and the Java Sea
Status of Microplastic Pollution in Aquatic Ecosystem with a Case Study on Cherating River, Malaysia
Get PDFMicroplastics are emerging contaminants owing to their potential to adsorb and release pollutants from the environment, transferring these pollutants to the food web. Most marine microplastics come from the terrestrial environment, mainly from inland freshwaters that are direct receivers of runoff from urban, industrial, and agricultural areas. The present study investigated the occurrence of microplastics in surface water samples taken from the Cherating river and the Cherating mangrove, Pahang along with a review of recent studies on microplastics abundance in aquatic ecosystems. Three sampling sites were established (two sites along the river and one site in a mangrove in the downstream of the river). In the up- and midstream regions, the river passes by residential, fishery and tourism areas, while the mangrove is located close to Cherating Beach. The highest microplastics abundance was discovered in the midstream region, with an average abundance 0.0070 ± 0.0033 particles/m3, followed by the mangrove (0.0051 ± 0.0053 particles/m3). Fragments with a size of 0.5 to 1.0 mm and white-colored microplastics were prevalent. The findings are similar to those from other microplastic studies (e.g. in Aveiro and Lisbon, Portugal; New England, USA; Kingston Harbour, Jamaica), but lower than microplastics studies in Asia (e.g. Yangtze river estuary and Hangjiang river, China). Overall, the findings provide background information on microplastics pollution in aquatic ecosystems
Mechanical Properties and Morphological Analysis of Copper Filled Aluminum Alloy Hybrid Matrix Composite
Get PDFThis paper presents the characterization of LM6 aluminum alloy with varying copper addition. LM6 is a soft, light-weight and corrosion resistant metal. Due to these characteristics, the material was selected to be added with copper to identify improved properties. The amount of copper addition was varied from 0%wt with intervals of 3%wt for every alloying run. Vibration casting, or vibration molding, was conducted. The vibration process is said to give a better result in terms of the alloy's grain size and arrangement. Mechanical testing and microstructure analysis were performed to prove the theory. Specimens with various amounts of copper were successfully produced and tested. The LM6 alloy specimen casted without copper and with vibration casting at 20 Hz had the highest tensile strength and percentage of elongation, while the LM6 alloy specimen casted with 9%wt of copper without mechanical vibration casting had the best mechanical properties based on the overall results and criteria. The percentage of copper addition that produced the optimum properties was found to be 9%wt of copper without vibration molding (hardness 46.2HRB, 125 MPa)
Influence of Electrode Distance on Electrical Energy Production of Microbial Fuel Cell using Tapioca Wastewater
Get PDFMicrobial fuel cell is one alternative technology that can be used to simultaneously solve problems related with wastewater production and energy demand. This study investigates the influence of electrode distance on power density in microbial fuel cell using tapioca wastewater. Graphite sheet without metal catalyst was used for both electrodes, separated by Nafion membranes. Four variations of electrode distance were used. MFC with highest electrode distance give the highest equilibrium OCV (676 mV), while the MFC with shortest electrode distance give the highest power density (7.74 mW/m2). EIS measurement suggested that the charge transfer resistance is dominant in all MFC configuration. Wastewater COD removal were in the range of 35-46 %, which were in accordance with the power density for all MFC
Power Quality Investigation of Single Phase Grid-connected Inverter of Photovoltaic System
Get PDFThere is a growing demand for renewable energy resources in countries all around the world. Among renewable energy resources, solar energy is a prominent and promising alternative to meet future electricity needs. Recently, the renewable energy regulations in Jordan have been modified to allow customers to install their own photovoltaic (PV) generators to cover their full energy consumption. This study investigated the power quality profile of single-phase grid-connected PV system in a typical Jordanian low voltage electrical system. The following electrical parameters were monitored: voltage, current, harmonics contents, total harmonics distortion (THD), active power, reactive power, and power factor. Detailed investigations and analyses were made
Study on the Extent of the Impact of Data Set Type on the Performance of ANFIS for Controlling the Speed of DC Motor
Get PDFThis paper introduces an adaptive neuro-fuzzy inference system (ANFIS) for tracking SEDC motor speed in order to optimize the parameters of the transient speed response by finding out the perfect training data provider for the ANFIS. The controller was adjusted using PI, PD and PIPD to generate data sets to configure the ANFIS rules. The performance of the ANFIS controllers using these the different data sets was investigated. The efficiencies of the three controllers were compared to each other, where the PI, PD, and PIPD configurations were replaced by ANFIS to enhance the dynamic action of the controller. The performance of the proposed configurations was tested under different operating situations. Matlab's Simulink toolbox was used to implement the designed controllers. The resultant responses proved that the ANFIS based on the PIPD dataset performed better than the ANFIS based on the PI and PD data sets. Moreover, the suggested controller showed a rapid dynamic response and delivered better performance under various operating conditions
Phytoremediation of Nutrients and Organic Carbon from Sago Mill Effluent using Water Hyacinth (Eichhornia crassipes)
Get PDFThe aim of this study was to investigate the ability of floating water hyacinth (Eichhornia crassipes) to survive under selected concentrations of sago mill effluent (SME) and determine the nutrient uptake by the plant. Phytoremediation at 10, 15, and 20% (VSME/Vwater) SME concentrations by water hyacinth was conducted under greenhouse conditions for 30 d in a batch type experiment. After 30 d of phytoremediation, the removal efficiency of chemical oxygen demand, ammonia and phosphorus from SME wastewater were (86.4% to 97.2%), (91.4% to 97.3%) and (80.4 to 97.2%), respectively. The results proved the efficiency of water hyacinth to polish SME wastewater
