Sunlight Intensity Research Articles

Chloroplast Genome Evolution in Four Montane Zingiberaceae Taxa in China.

Chloroplasts are critical to plant survival and adaptive evolution. The comparison of chloroplast genomes could provide insight into the adaptive evolution of closely related species. To identify potential adaptive evolution in the chloroplast genomes of four montane Zingiberaceae taxa (Cautleya, Roscoea, Rhynchanthus, and Pommereschea) that inhabit distinct habitats in the mountains of Yunnan, China, the nucleotide sequences of 13 complete chloroplast genomes, including five newly sequenced species, were characterized and compared. The five newly sequenced chloroplast genomes (162,878–163,831 bp) possessed typical quadripartite structures, which included a large single copy (LSC) region, a small single copy (SSC) region, and a pair of inverted repeat regions (IRa and IRb), and even though the structure was highly conserved among the 13 taxa, one of the rps19 genes was absent in Cautleya, possibly due to expansion of the LSC region. Positive selection of rpoA and ycf2 suggests that these montane species have experienced adaptive evolution to habitats with different sunlight intensities and that adaptation related to the chloroplast genome has played an important role in the evolution of Zingiberaceae taxa.

Microclimate Characteristics On Oil Palm (Elaeis guineensis Jacq.) And Agarwood (Aquilaria malaccensis Lamrk.) Agroforestry System


 In general, oil palm plants are cultivated using a monoculture system. The monoculture system is profitable from an economic perspective and harms the environment; one is the microclimate. One of the efforts to reduce the negative impact of the oil palm monoculture system is to apply the oil palm agroforestry system with agarwood. This research is conducted on smallholder oil palm plantations in Bukit Kemuning Village, Tapung Hulu Sub District, Kampar District, Riau Province. This research was conducted using a survey method, which was done by choosing a location intentionally. Determination of the research location using purposive sampling method, that is, on land found agroforestry systems of oil palm plants with agarwood and oil palm monoculture systems in the same location. Microclimate observations are carried out by measuring air temperature, air humidity, and sunlight intensity. Measurement of air temperature and humidity uses the Temperature and Humidity Data Logger, while the sunlight intensity measurement uses the Lux Meter Data Logger tool. Measurements are carried out one day a week for three months, for getting 12 times of data retrieval. The recording is carried out from 07.00 am to 05.00 pm, with 15 minutes intervals. Microclimate data on agroforestry and monoculture systems are analyzed in comparative descriptive analysis. Based on the results of the study, it is concluded that the microclimate in the agroforestry system of oil palm and agarwood was better than that of the oil palm monoculture system, where the light intensity and air temperature in the agroforestry system are lower than the monoculture system, and the humidity in the agroforestry system higher than the monoculture system.
 In general, oil palm plants are cultivated using a monoculture system. Monoculture system is profitable from an economic perspective, but also has a negative impact on the environment, one of which is the micro climate. One of the efforts to reduce the negative impact of the oil palm monoculture system is to apply the oil palm agroforestry system with gaharu. This research is conducted on smallholder oil palm plantations in Bukit Kemuning Village, Tapung Hulu Sub District, Kampar District, Riau Province. This research is conducted using a survey method. Determination of the research location using purposive sampling method, namely on land found agroforestry systems of oil palm plants with gaharu and oil palm monoculture systems in one stretch. Microclimate observations are carried out by measuring air temperature, air humidity, and sunlight intensity. Measurement of air temperature and humidity uses the Temperature and Humidity Data Logger, while the measurement of sunlight intensity uses the Lux Meter Data Logger tool. Measurements are carried out one day a week for 3 months, for getting 12 times of data retrieval. Recording is done at 07.00 am up to 05.00 pm with 15 minute intervals. Microclimate data on agroforestry and monoculture systems are analyzed in comparative descriptive analysis. Based on the results of the study, it is concluded that the microclimate in the agroforestry system of oil palm and gaharu was better than that of the oil palm monoculture system, where the light intensity and air temperature in the agroforestry system are lower than the monoculture system, and the humidity in the agroforestry system higher than the monoculture system

Arduino-based Dual Axis Solar Tracking System Prototype

Since solar energy is an infinite source of energy, it can be used as a suitable alternative energy source. One of the technological attempts to utilize solar energy is the use of solar panels. A solar panel is a device consisting of a series of solar cells that can convert sunlight energy into electrical energy. The generated electrical energy adjusts the intensity of the received sunlight. However, in its application, most solar cells are statically placed (not following the movement of the sun), where the position of the solar panels only leads to one specific preventing optimal absorption of the intensity of sunlight and resulting electrical energy generation. Therefore, we need a solar tracking system that can automatically control the solar panels to track the movement of the sunlight so that they can absorb the sunlight optimally. The solar tracker created in this research consists of monocrystalline solar panels, LDRs, INA219 sensor, Arduino board, and servo motors. Data collection was carried out for six hours on three consecutive days. According to this study, the greatest difference in power generated by solar panels occurs between 12:00 and 13:00 WIB, with an average value of active solar tracker power of 0.5 W and static solar tracker value of 0.34 W.

Potential of natural sunlight for microalgae cultivation in Yogyakarta

The study of microalgae is widely developed on a laboratory scale. The large-scale applications of microalgae such as large photo-bioreactors or commercial ponds are not well established due to some obstacles. The high cost of artificial lighting in microalgae cultivation is one of the obstacles. Markedly, the natural sunlight intensity is high every month for a whole year in Indonesia. This natural sunlight may serve as a low-cost lighting source for microalgae cultivation in a tropical country such as Indonesia. However, the basic knowledge of whether the natural sunlight in Indonesia is sufficient or not for microalgae cultivation is poorly understood. This study was performed to investigate whether sunlight in Indonesia, particularly in Yogyakarta, is sufficient or not for microalgae cultivation in the absence of artificial lighting. The sun lighting period data from January 2019 to June 2020 were collected from BMKG (Badan Meteorologi Klimatologi dan Geofisika) website. The sun lighting period data were converted into solar radiation data. The Liliefors test was performed to evaluate the distribution of the solar radiation data. To confirm whether the sun lighting in Yogyakarta is sufficient for microalgae cultivation or not, the parametric statistical test namely single sample T-test was used in this study. The Liliefors test showed that solar radiation in Yogyakarta (January 2019 to June 2020) was normally distributed. The calculated Liliefors value (0.14) was less than Liliefors table value (2.00). The T-test results revealed that the solar radiation in Yogyakarta is equal to or higher than the sufficient solar radiation (reference) for microalgae cultivation (795 kWh/m2). The calculated t value (0.65) was higher than the t table value (-1.74). When taken together, our findings suggest that natural sunlight in Yogyakarta is sufficient as a lighting source for microalgae cultivation.

Multivariable Coordinated Nonlinear Gain Droop Control for PV-Battery Hybrid DC Microgrid Access System via a T-S Fuzzy Decision Approach

The PV-Battery hybrid DC microgrid is an important structural form for distributed renewable energy microgrid applications. This paper focuses on improving the access utilization rate of PV-Battery energy and enhancing the access stability of the DC bus voltage. Firstly, based on the voltage droop control method for multi-source access system, the relationship between the power margin of PV-Battery energy and the regulation of DC bus voltage deviation is analyzed. Then, a multivariable T-S fuzzy decision approach is used to design a nonlinear virtual resistance-based voltage droop gain coefficient function, which achieves a highly adaptive coordinated distribution of PV-Battery power as well as supports DC bus voltage stabilization. The T-S fuzzy input variables include the DC bus voltage deviation of the access point, the state of charge of the battery, and the PV sunlight intensity. Finally, the simulation system is built employing MATLAB/Simulink, and the feasibility and effectiveness of the proposed strategy are verified through multi-scheme simulations.

Degradation of Dimethoate Pesticide in Soil: Impact of Soil Moisture and Enhanced Sunlight Intensity

Degradation of Dimethoate Pesticide in Soil: Impact of Soil Moisture and Enhanced Sunlight Intensity

Sustainable solar energy harvesting using phase change material (PCM) embedded pyroelectric system

This work proposes a smart control of pyroelectric energy harvesting, based on the form-stable phase change material (PCM) composites utilizing polyethylene glycol (PEG) and 1-tetradecanol (1-TD). Solar light transmitted into a pyroelectric system made of window glass and indium tin oxide (ITO) pyro-electrode can provoke thermo-electric energy conversion by the change of temperature difference. The transparent pyro-electrode allows the transmitted solar light to reach the other side of the window glass. The PCM composite placed at the side can reduce the temperature fluctuation to control the change of temperature difference during the light-on/-off process. Since pyroelectric harvesting effects depends on the intensity of sunlight, different solar irradiations (10, 15, and 20 mW/cm2) were applied to the energy harvesting system in this study. The pyro-electrode could generate stable and continuous electrical energy by the combination of PCM composites. In addition, the underlying physics behind the system are theoretically modeled by utilizing the finite element method (FEM).

Monitoring Iklim Mikro pada Greenhouse Secara Real Time Menggunakan Internet of Things (IoT) Berbasis Thingspeak

Farm cultivation in the highlands is constrained by the long rainy season, less efficient sunlight and susceptible to pests and diseases. One of the solutions in cayenne pepper cultivation is using hydroponics and greenhouse s to minimize pests and diseases that come from the soil and are carried by the wind. The purpose of this research is to produce "SMART-IGHIOT" a control system based on the Internet of Things using Dutch bucket hydroponics in a portable greenhouse. The technology applied is in the form of monitoring and controlling temperature, humidity, air temperature and light intensity using sensors integrated with the ESP32 microcontroller. The ESP32 is connected to the Thingspeak webserver to display sensor measurement results in real-time. The design of the monitoring system for light intensity, temperature and humidity in the greenhouse can be maximized so that environmental conditions can be optimized. The performance of using greenhouse s can maximize the intensity of sunlight, the highest at 12.00, while the lowest temperature at 03.00 to 05.00 WIB. While the highest temperature is at 13.00 and the highest humidity is at night. Keywords: dutch bucket, greenhouse, IoT, microclimate, Thingspeak

Architecting Hybrid Donor–Acceptor Dendritic Nanosheets Based on Polyoxometalate and Porphyrin for High‐Yield Solar Water Purification

AbstractHarvesting solar energy for saline and polluted water purification is a sustainable and affordable solution to alleviate the stress on water shortages. However, the water evaporation rate relies on high optical intensity and suffers from inadequate energy conversion. Herein, a novel hybrid donor–acceptor dendritic nanosheets (denoted as DNS) composed of phosphomolybdic acid (PMA) clusters and porphyrin ligands is reported. Experimental results and molecular dynamics simulations indicate that the PMA and porphyrin are oriented attachment and assembled into a stable nanostructure. Benefiting from the advantages of the unique structure and photosensitive components, the DNS exhibits high evaporation rate of 2.23 kg m‐2 h‐1 with 90.9% energy efficiency under 1 sun irradiation. It is noteworthy that the evaporation performance is upgraded by innovative technology, and even under 0.5 sun that is close to the natural sunlight intensity, the evaporation rate reaches up to 1.31 kg m‐2 h‐1, which exceeds that of the vast majority of the reported evaporators. Furthermore, this evaporator also displays excellent seawater desalination and wastewater decontamination based on photo‐thermal distillation, highlighting its potential application toward water purification.

Design of absorptive multilayer coatings for satellite thin-film solar cells and studying the dispersion effect on them

Using the Transfer Matrix method and Abele’s Matrix method, several types of absorptive multilayer structures have been proposed exclusively for thin-film solar cells, which can absorb the solar spectrum in the wavelength range from 300 nm to 3000 nm with the angles of incidence from 0° to 90° considerably. Furthermore, the absorption rate of these structures has been investigated and calculated at the angle of incidence 70° with considering the dispersion effect and making use of the Sellmeier Equations. For coherency sunlight, the results illustrate that the absorption rate of all structures has been increased significantly by applying the dispersion effect compared with the absence of the dispersion effect for TM waves while the absorption rate has been expanded up to 40% in all structures virtually with undergoing optimization for incoherency sunlight. As a result, the four-layer structure with the maximum absorption rate, without applying the dispersion relation has been absorbed 91% of the sunlight on average while utilizing the dispersion relation has been absorbed 99% of the sunlight on average for TM waves. In addition, the magnetic fields under dispersion effect have been reduced to keep safe the structures and also intensity of sunlight was monotone in TM waves and incoherency light to preserve them against solar intensity fluctuations at various angles.

Light Management for Enhancing Optical Gain in a Solar‐Pumped Fiber Laser Employing a Solid‐State Luminescent Solar Concentrator

Optical gain of 8.3 km−1 is obtained in a neodymium‐doped silica fiber under simulated sunlight (intensity = 2.1 kW m−2). The fiber gain medium (length = 50 m) is coiled and attached to a solid‐state luminescent solar concentrator (LSC) disk (diameter = 180 mm). The disk/fiber unit is placed in a cavity comprising highly reflective (HRM) and dichroic (DM) mirrors to increase the photon confinement by a factor of 2.2 compared with a liquid LSC (also employing HRM/DM). The enhancement is mainly due to the air gap between HRM/DM and LSC, which affords total internal reflection (TIR) in the solid‐state LSC and an ideal boundary condition for the multilayer mirrors. The numerical calculations indicate that an additional 2.2‐times enhancement is achievable with a side wall exhibiting 90% diffuse reflection. This has been experimentally confirmed (1.9‐times optical‐gain enhancement is realized by adding a polytetrafluoroethylene side‐wall reflector). Overall, the solid‐state LSC‐based solar‐pumped laser (SPL) comprising reflective side walls exhibits a gain factor of 4.2, which is superior to its liquid‐state predecessor. Further improvements employing a solid‐state LSC design and fiber optimization will facilitate the market penetration of SPLs.

Modelling of a multistage reciprocating humidifier and performance analysis for various packing configurations

Excessive energy consumption has led to environmental problems and climate change. Cooling of the building is the key reason for energy consumption in hot regions. Due to the consistent sunlight intensity and high temperatures, the use of cooling units are inevitable. Single stage humidifiers are widely used which provided evaporative cooling consistently. Present work focuses on designing and fabricating a novel multistage reciprocating humidifier operated by a cam follower mechanism. Four packings are operating at four different positions in dynamic conditions. A theoretical model has been constructed to predict the thermal performance parameters using commercially available celdek packing 7090, 5090, honeycomb and corrugated. Theoretically predicted results agree with the experimental results with a maximum deviation of 2.1%., 4.8% and 8.6% for DBT, humidity ratio and saturation efficiency. Variation of the results is studied stage wise, and its change in performance is analyzed. Simulated results indicated that celdek 7090 outperformed the others in terms of change in dry bulb temperature, humidity ratio and saturation efficiency by 0.6%, 0.8% and 1.2% for the airflow rate of 5.6 m/s, respectively. Increasing the pad thickness showed improvement in the drop in dry bulb temperature, increased humidity ratio, and saturation efficiency. It is recommended to use zig-zag celdek 7090 type with 15 cm thickness in a multistage cooler to obtain the best performance for cooling applications in buildings with less cost.

Fuzzy based sensorless tracking controller on the dual-axis PV panel for optimizing the power production

In general active sun trackers move because they respond to light sensors that measure the intensity of sunlight. However, sensor-based trackers are usually more expensive than sensor-less trackers. In addition, based on several studies, a comparison between the sensor and sensorless based tracker only reports lower tracking error and higher power generation for sensor-based than sensorless tracker. However, it does not include an analysis of energy use on the sensor. Therefore, this study aims to design a sensorless closed-loop tracking system for solar panels with two degrees of freedom. The tracking controller in this study is based on the Fuzzy Logic Controller (FLC) method. In this study, a dual-axis PV can increase power output by 20.2% compared to a fixed PV (0 ° axis position). In comparison to a fixed PV, dual-axis PV adjusts the solar panel perpendicular to the sun's position to optimize electrical conversion.

“The contribution of double skin roof coupled with thermo reflective paint to improve thermal and energy performance for the ‘Mozabit’ houses: Case of Beni Isguen’s Ksar in southern Algeria”

In traditional cities of hot and arid climate regions, roofs are usually the surfaces most exposed to intense sunlight in summer. This leads to high temperatures inside the houses and forces the inhabitants to escape to the terraces at night. On the other hand, some residents use air conditioning and therefore increase energy consumption. This work aims to study the contribution of a double skin roof coupled with a thermo-reflective paint on the reduction of indoor temperature and energy consumption in house located in the Ksar of Beni Isguen in southern Algeria. Firstly, the problem of overheating was identified through temperature and humidity measurements for traditional dwelling in hot season. Secondly, a model of double skin roof coupled with thermo-reflective paint was developed and numerically simulated using TRNSYS software. The obtained results showed that in summer, the temperatures in traditional houses are high compared to the comfort zone. The average indoor operating temperatures exceeded 37 °C during different hours of the day, over the investigation period of three representative days of hot season. Nevertheless, the proposed model reduces the indoor operative temperature by 5 °C. Also, the model was validated against in situ measurements, whose results showed a consistency between the measured and simulated temperature values. In addition, thermal simulation results performed over a period of one year indicate that the overall energy consumption required for cooling loads is reduced by 572 kWh i.e. 66% when optimizing the roof thermal performance.

Eco-design of portable solar-powered telescopic lamp for off-grid areas in Indonesia

<p><span lang="EN-US">This study describes the development of eco-design of portable solar-powered telescopic lamp for off-grid area in Indonesia. Several design requirements for the lamp, namely, sustainability, portability, affordability, and reliability, are the objectives of the design process in this study. Sustainability is achieved through renewable energy and the application of eco-design principles. Portability means it is lightweight, compact and can be carried anywhere inside a tube. This solar-powered telescopic lamp was designed with a 3.7 V, 15.6 Ah battery power specification such that the battery power is around 57.72 Wh. The optimal use of the battery is 80% of the total battery power that is 46.176 Wh. With a power of 46,176 Wh, the battery can turn on the LED strip light with a 4.8 W power specification for 9.62 h. The test results showed that the telescopic lamp endurance met the expected specifications. The real consumed power by the LED strips was around 1.9 W. The charging test using solar panels with 12 Wp specifications showed that it will be fully charged in around 3.8 h. However, the performance of the telescopic lamp, especially in the charging process, is affected by the environment condition, such as sunlight intensity, ambient temperature, and humidity.</span></p>

Microcontroller-based Artificial Lighting to Help Growth the Seedling Pakcoy

Improving efficiency and quality in farming activities is important reason of developing technology to support agriculture. Technology in agriculture such as image processing, Internet of Things (IoT), Artificial Intelligence, Big Data, and Artificial Lighting gives increasing trends. Artificial lighting technology has high impact to support agriculture in an area that has low sun light intensity such as in rainy season. Farmer has a difficulty to cultivating plant especially in early stage in rainy season. This problem happen because of the intensity of sun light is very minimum. Artificial lighting is a technology to solve early stage cultivating problem in rainy season. This technology can support agriculture for cultivating plant with minimum sun light. Artificial lighting contains light emitting diode (LED) that is laid out as an array. This research goal is to make an artificial lighting prototype to support early stage cultivating. Pakcoy is a plant that used to observe artificial lighting impact for early stage Pakcoy cultivation. This research shows Pakcoy plant placed in the prototype gives significant growth compared with a plant which placed in low light room. Pakcoy plant in artificial lighting gives 2 4 leaves, the height is 1.5 5cm, and from 18 seeds 10 is grow. This research can conclude that artificial lighting prototype can support early stage Pakcoy cultivation.

Sistem Monitoring Penentuan Pergerakan Posisi Panel Surya Terintegrasi Internet Of Things

Due to the increasing demand for energy, alternative energy is needed. One of them is energy that comes from the sun. To utilize solar energy, solar panels are needed which are used to collect solar energy which will be converted into electrical energy. The problem is to optimize the work of the solar panel, a design for determining the position of the solar panel must be made so that it is always focused on the direction of the arrival of the sun. Design of solar panel position monitoring system based on the Internet of Things has a purpose as a monitoring system in optimizing the light reception received by solar panels in real time. The method used is the dual axis tracking method, which is a method that can make flexible solar panel movements follow the direction of the maximum sunlight intensity. The parameters monitored from this research are the value of analog voltage from the four LDR light sensors, two angles of dual axis movement and description of the the solar panel position. From the tests that have been carried out, the system can work well as solar panel movement position monitoring system based on the Internet of Things.

Sun Position Forecasting Menggunakan Metode RNN – LSTM Sebagai Referensi Pengendalian Daya Solar Cell

Solar energy is used as electrical energy for daily life by using solar cell. There are several models for maximizing the absorption of solar cell power by using reflectors and solar tracking. Reflector focuses sunlight on the solar cell to get maximum light. Solar tracking real-time tracking the sun by moving two motors and sensors to read the direction of the sun's angle. Both have the disadvantage of tracking the sun continuously. So it is necessary to optimize the system to determine the tilt angle of the actuator and be able to streamline the intensity of sunlight that can be absorbed by solar cells with the identification system that can be done in realtime or directly to minimize the occurrence of power wastage. Prediction is one of the most important elements for decision-makers of the problems that occur above. In this paper, the method used in predicting the sun's angle is by using the Recurrent Neural Network (RNN) method which has a Long-Short Term Memory (LSTM) structure in the RNN system. In this reseacrh, the data used to predict the sun angle from the sunscalc.org site in the area of the University of Muhammadiyah Malang campus 3 with a period of one year. Testing with the RNN-LSTM structure is done with two different prediction models, namely weekly, monthly, and annual data for daily data results, and hourly data for daily data for one week. The test results on weekly data detect Root Mean Square Error of 0.12%, the monthly data is 0.1% and the annual data is 0.24%. The monthly data model has the fewest error values, so predictive data has a high degree of accuracy.

Optimizing the Use of MPPT in PLTS for Hybrid Systems by Using STS as a Transfer Switch

To save energy nowadays is recommended to switch to renewable energy sources. In Indonesia, solar energy is abundant, so PLTS is made. The supply of PLTS is expected to reach maximum use. However, solar panels have many obstacles such as variations in temperature and sunlight intensity, MPPT systems are needed to find the maximum power point of the solar panels. Unfortunately, in Indonesia, the sunlight of short duration with the ideal irradiation time that can produce electricity from solar panels is 4 to 5 hours per day, so a PLN supply is still needed to support the continuity of the power supply. Because two sources are used, there is a problem where the load needs high continuity during power switching, so STS (Static Transfer Switch) is used for very fast power switching. Simulation results, when using EMR (Electromechanical Relay) the power transfer process takes 50ms or 5 cycles while STS takes 2ms or ¼ cycles. With very fast response to STS, sensitive equipment is kept safe from power quality disturbances such as voltage sag and voltage swell.

Response of foragers of the giant Himalayan honey bee, Apis laboriosa, to microclimates in agro-net and climate control greenhouses

The giant honey bee Apis laboriosa is endemic in the high-elevation zone of the Himalaya extending from central to eastern belt and its adjacent mountain ranges. Its abundance is however reported to decline in recent decades. The present study aims to find out the favourable microclimate for foraging activity of A. laboriosa. Therefore, to explore the response of foragers to ambient temperature, relative humidity and sunlight intensity, experiments were conducted in captivity using two types of greenhouses: agro-net and climate control greenhouse. One colony of a combless cluster in each greenhouse was monitored for a period of 22 days. Monitoring was done by counting the number of foragers on honey, sugar syrup and forage plants at an interval of 1 hour. The microclimate of the greenhouses differs in sunlight intensity and relative humidity. Principal component analysis showed that the foraging activity is positively associated with sunlight intensity and relative humidity and is negatively associated with ambient temperature. Higher number of active foragers in the climate control greenhouse shows its relative humidity and sunlight intensity as favourable for foraging activity of A. laboriosa compared to the agro-net greenhouse. The result is also indicative of possible impact of change in sunlight intensity and relative humidity on the foraging activity of A. laboriosa that may affect pollination of the native plants and honey production.