CD Home Nanogrid: Avoiding Standby Consumption and Diminishing Ripple Amplitudes

<div>The nanogrids are the basic unit to develop more complex and stronger distributed systems. DC nanogrids allow a better performance and higher efficiency than the AC nanogrids. The lack of DC home appliances in the local market has resulted in a slow development of DC Home Nanogrids (DCHN). The Compact Fluorescent Lamp (CFL) and LED are used in power electronics as high efficiency and low cost lightning components. However, these devices represent a source of emission of harmonics in Alternating Current (AC) and Direct Current (DC) systems, due to their nonlinear behavior. In this paper a mathematical model for the nonlinear loads and experimental results of the voltage and current ripple in a DCHN are presented. The CFL and LED lamps are used as our nonlinear loads for test the model. The model explains well the experimental results of how the ripple amplitude is reduced. We also present the effect of decreasing the ripple amplitude when it is incorporated an induction stove in standby mode to the DCHN, which also is explained by the model.</div>

CD Home Nanogrid: Avoiding Standby Consumption and Diminishing Ripple Amplitudes

<div>The nanogrids are the basic unit to develop more complex and stronger distributed systems. DC nanogrids allow a better performance and higher efficiency than the AC nanogrids. The lack of DC home appliances in the local market has resulted in a slow development of DC Home Nanogrids (DCHN). The Compact Fluorescent Lamp (CFL) and LED are used in power electronics as high efficiency and low cost lightning components. However, these devices represent a source of emission of harmonics in Alternating Current (AC) and Direct Current (DC) systems, due to their nonlinear behavior. In this paper a mathematical model for the nonlinear loads and experimental results of the voltage and current ripple in a DCHN are presented. The CFL and LED lamps are used as our nonlinear loads for test the model. The model explains well the experimental results of how the ripple amplitude is reduced. We also present the effect of decreasing the ripple amplitude when it is incorporated an induction stove in standby mode to the DCHN, which also is explained by the model.</div>

Photocatalytic degradation of caffeine and E. coli inactivation using silver oxide nanoparticles obtained by a facile green co-reduction method

In this study, silver oxide nanoparticles (Ag2O-NPs) were synthesized from silver nitrate using green amaranth leaf extract as reducing agent. The degradation of caffeine and inactivation of Escherichia coli by Ag2O-NPs was studied under compact fluorescent lamp illumination irradiation. Apart from that, the antibacterial and antioxidant activities of Ag2O-NPs were also examined. Synthesized Ag2O-NPs were shaped like monodispersed husk, and cubic structured with surface area and average particle size was detected to be 100.21 (m2/g) and 81 nm respectively. Antioxidant efficacy of the Ag2O-NPs was evaluated using 1, 1-diphenyl-2-picrylhydrazyl and 91% inhibition was achieved with 100 µg Ag2O-NPs. Bacteriocidic propensity of Ag2O-NPs was examined against the S. aureus and P. aeruginosa by disc diffusion, minimum inhibitory concentration (MIC), Live and dead assay. It was observed that the NPs have higher bactericidal effect on Gram-negative as compared to Gram-positive bacteria. Up to 96% photocatalytic inactivation of E. coli was achieved using 30 µg/mL of NPs, Photocatalytic degradation of caffeine (50 ppm initial concentration) was observed to be 99% at pH 9 in 15 h using 50 mg/L of Ag2O NPs. These results indicate that Ag2O NPs can be employed in environmental applications like harmful bacteria inactivation and organic pollutants degradation.

Effect of the Harmonic Voltage Distortion on the Efficiency of a Compact Fluorescent Lamp

This paper evaluates the effect of the voltage harmonic distortion over the efficiency of a compact fluorescent lamp that is fed with a constant RMS voltage and constant frequency. Several works have been published about the assessment of compact fluorescent lamps, but the effect of the voltage distortion over the efficiency is still an open topic. This work focuses on designing an experiment to estimate the efficiency of a compact fluorescent lamp while changing the voltage harmonic distortion of the power supply. First, a mathematical model that represents a bus susceptible to harmonic distortion (high impedance) that feeds the compact fluorescent lamp is analyzed. Then the mathematical model is reproduced through a test bench in a laboratory of rotating electrical machines. The test bench produces a three-phase bus with constant voltage and frequency, and variable voltage harmonic distortion. The compact fluorescent lamp is subjected to varying harmonic voltage distortion while recording its electrical variables and the produced lumens to estimate its efficiency. That is a practical approach to calculate the lamp efficiency while several works limit their scope measuring only the efficiency of the input converter. The experimental results show that a variation of the voltage harmonic distortion of 8 % on a compact fluorescent lamp reduces its efficiency. Those results put into evidence the importance of regulating harmonic distortion limits to reduce or prevent the increment of power losses caused by harmonic components.

Analysis of Energy and Cost Performance of Retrofitting Fluorescent Tubes with Compact Fluorescent and Light Emitting Diode Lamps

Over the years, visual comfort has been described as a major requirement needed to enhance optimal performance of occupants in any learning environment in tertiary institutions. This is reflected in the poor performance of the commonly used Fluorescent Lamps (FL) occasioned by its constant burn-off, high failure rate and reduced durability. Hence, there is a shift to the adoption of Compact Fluorescent Lamp (CFL) and Light Emitting Diode (LED). This study therefore examined the pattern of electricity consumption involving the adoption of FL, CFL and LED in the purposively selected lecture theatres of Obafemi Awolowo University, Ile-Ife, Nigeria. The study was carried out using energy monitor to obtain the consumption data of the lamps for periodic logging at intervals of 1 hr, 3 hrs, 6 hrs, 12 hrs, 1 day, 7 days, 1 month and 3 months respectively; and also to determine the payback period of each of the lamps. From the data collected, patterns of electricity used, electricity savings were calculated and compared to establish performance potentials of each of the lamps. The study found that there was a significant difference in the pattern of electricity consumption of FLs compared with that of CFLs and LEDs, but a reduced margin existed between CFLs and LED lamps. It showed that the FLs consumed 681.576 kWh, 1619.466 kWh and 5652.432 kWh, CFLs consumed 387.302 kWh, 692.479 kWh and 1936.600 kWh, while LED consumed 294.188 kWh, 426.608 kWh and 1499.015 kWh. There were significant differences in consumption with 43, 47 and 65% reduction in electricity consumption using CFLs while 57, 73 and 73% using LED fittings were obtained. The CFLs performed better in terms of return on investments by having a lower payback period when compared to LED. The study concluded that replacing FL with CFL and LED would be desirable option in order to enhance optimal performance of lecture theatres, but in terms of payback period, it would be beneficial to retrofit FLs with CFLs.

Photocatalytic Degradation of Rhodamine B by C and N Codoped TiO2 Nanoparticles under Visible-Light Irradiation

C and N codoped TiO2 nanoparticles were synthesized via a solvothermal method. The degradation of Rhodamine B by the photocatalyst C, N-TiO2 was investigated under visible-light irradiation generated by using a 36 W compact fluorescent lamp which is characterized by wavelengths from 400 to 650 nm. The structure and properties of the obtained photocatalyst have been systematically investigated using X-ray diffraction, TEM, UV-Vis, FT-IR, and BET techniques. The experimental results revealed that C, N codoped TiO2 nanoparticles were successfully synthesized, with an average diameter of 9.1 nm. C, N-TiO2 nanoparticles exhibited an energy band gap of 2.90 eV, which were lower than pristine TiO2 (3.34 eV), C-TiO2 (3.2 eV), and N-TiO2 (3.03 eV). The degradation of Rhodamine B by C, N-TiO2 indicated that, under visible-light irradiation, the optimal dose of the photocatalyst was 1.8 g/L, and the removal of Rhodamine B was almost complete after 3 hours of reaction. The photocatalytic degradation of Rhodamine B in the range of 5–100 mg/L showed that the process followed the first-order kinetics according to the Langmuir–Hinshelwood model. The highest apparent rate constant (0.0427 min−1) was obtained when the initial concentration of Rhodamine B was 5 mg/L, whereas the former decreased with the increase in the initial concentration of Rhodamine B. Moreover, C and N codoped TiO2 nanoparticles presented a high potential for recycling, which was characterized by a removal efficiency of more than 86% after three cycles.

Penerapan High Power LED (HPL) sebagai Penarik Datangnya Ikan Berbasis Mikrokontroler

Kelong is a rectangular-shaped house made of basic material is logs of various sizes that are bound square and below which are given drums to float. Based on the results of monitoring of fishermen on Bintan Island, fish gathered at a fishing distance by using white lights with a power of 2000 watts divided separately on four power lamps each of 500 watts. Currently fishermen choose to use this type of CFL (compact fluorescent lamp) lamp to attract fish's attention and because this type of lamp has an affordable price. In its application, the type of high power LED lamp with two colors, white and green, each is controlled based on water turbidity parameters with a percentage value of 0-33%, 34-66%, and 67-100%. PWM (Pulse Width Modulation) high power LED works with a percentage of 25% when turbidity <33%, percentage of 50% if turbidity> 33%, and percentage of 100% if turbidity ≥ 66%. The use of turbidity sensors that are connected to the Arduino uno is used as a control media that is equipped with an analog signal module to measure water turbidity. Based on its application the high power green LED produces 6 ounces and 2.5 ounces of high power white LED. Intisari Kelong adalah rumah berbentuk segi empat yang terbuat dari bahan dasarnya adalah kayu gelondongan berbagai ukuran yang diikat persegi empat dan di bawahnya diberi drum-drum untuk mengapung. Berdasarkan hasil pantauan pada nelayan di Pulau Bintan, ikan berkumpul pada jarak tangkap nelayan menggunakan lampu berwarna putih dengan daya sebesar 2000 watt yang dibagi terpisah pada empat buah lampu berdaya masing-masing sebesar 500 watt. Saat ini nelayan memilih menggunakan jenis lampu CFL (compact fluorescent lamp) untuk menarik perhatian ikan dan karena jenis lampu ini memiliki harga yang terjangkau. Pada penerapannya digunakan jenis lampu high power LED dengan dua warna yaitu putih dan hijau, masing – masing dikontrol berdasarkan parameter kekeruhan air dengan batasan nilai persentase 0-33%, 34-66%, dan 67-100% . PWM (Pulse Width Modulation) high power LED bekerja dengan persentase 25% apabila turbidity < 33%, persentase 50% apabila turbidity > 33%, dan persentase 100% apabila turbidity ≥ 66%. Penggunaan sensor turbidity yang dihubungkan dengan Arduino uno digunakan sebagai media pengendali yang sudah dilengkapi dengan modul sinyal analog untuk mengukur kekeruhan air. Berdasarkan penerapaanya high power LED warna hijau menghasilkan sebesar 6 ons dan high power LED warna putih 2,5 ons.