The effect of dust on the performance of solar photovoltaic module: Case studies in Nusa Tenggara Timur, Indonesia and Perth, Western Australia

The performance of a PV module tends to decrease as dust impinges onto its cover surface. The attached dust diminishes the illumination by absorbing and scattering sunlight received by the solar module. Degradation caused by dust is temporary, but it should not be underestimated. Many studies investigated the influence of dust accumulation on optical properties and its impact on PV module performance. However, less attention was given to the effect of dust on small scale PV systems such as residential systems. Also, most of the preceding literature were not supported with an economic analysis which can inform maintenance activity scheduling. This study aims to identify the effect of dust on the performance of solar PV modules in varying environmental conditions and cost effective maintenance schedule for both solar home system and residential grid-connected system. To study the effect of dust on PV performance in different climate areas, research was conducted in Nusa Tenggara Timur (NTT), Indonesia and Perth, Western Australia. A series of experiments in the laboratory was performed. A solar simulator was used to measure PV modules‟ performance. A combination of a spectrophotometer, scanning electron microscope, electron dispersive spectroscope and an X-ray diffraction machine were used to examine properties of dust. In addition to the laboratory experiments, a field study was carried out to investigate the effect of dust accumulated naturally on PV performance degradation deployed in the two regions. Characterization results revealed that dust in Perth exhibited angular shapes dominated by quartz, while porous particles with a large amount of calcium oxide were observed in dust from NTT. The grain size analysis showed that the percentage of clay and very fine silt of dust from Perth was higher than that from NTT. Therefore, at the same density, dust from Perth passed less light than that from NTT. Power output produced by PVs coated artificially with dust from Perth was lower than that from NTT although the difference was not statistically significant. The performance degradation of PV modules deployed in the field varied with season. In Perth, power output of the modules which was maximal at the beginning of summer decreased significantly at the end of the season. The performance was then increased, approaching the initial position at the end of autumn and reached a peak at the end of winter. A similar decrease in the summer‟s performance was observed in the modules at the end of spring. In NTT, the performance which was maximal at the beginning of wet season dropped slightly at the end of the season and had significantly decreased at the end of the dry season. PV performance variations were in agreement with dust density deposited on the examined PV modules. Seasons with less rainfall demonstrated more accumulation of dust compared to those with greater rainfall. In addition, as the tilt angle increased dust deposition decreased; as a result, the average transmittance of dust increased. For a one year period, power loss of PV modules due to dust was 4 - 6% and 16 - 18% for Perth and NTT, respectively. The greater degradation in NTT is attributed to the lower tilt angle of the PV modules, the higher relative humidity, and the longer dry season in the region. The effect of dust on PV performance for a long time period carried out in Perth revealed that the degradation of Pmax output of PV samples deployed for almost 18 years without any cleaning procedures were 8 - 12%. These losses are higher than that measured for the one year period and indicate that natural cleaning agents such as rain and wind could not remove dust particles attached on the surface of the PV modules perfectly. In addition to the power decrease, observation results in the field showed that the modules exhibited some permanent degradation indicated by corrosion, delamination, and discoloration. This may be attributed to hot spot phenomenon caused by dust for a long time period besides the age of the examined PV modules. Economic analysis revealed that annual cost of production losses of residential PV systems in Perth and NTT with a degradation pattern as measured in the field was higher than the maintenance cost activities. Consequently, the system in Perth needs once cleaning in a year, meanwhile twice for the system in NTT. This thesis, therefore, suggested more intense cleaning should be applied for PV modules mounted at lower latitude and deployed in a tropical climate area. Standard dust de-rating factor (5%) stipulated by Australian/New Zealand Standard 4509.2:2010 was appropriate for modelling a grid-connected PV system in Perth, but, the system required cleaning once per year. Conversely, the standard soiling loss factor of 5% was not suitable for solar home system modelling in NTT as the estimation of the impact of dust was underestimated. Thus, this thesis recommended that the soiling de-rating factor should vary between regions and with season. This will improve the accuracy and the reliability of PV system models

KAJIAN REKONSILIASI TERHADAP PERAN PENDETA BAGI WARGA BINAAN PEMASYARAKATAN DI RUTAN KELAS IIB KOTA KUPANG

Dalam bentuk masyarakat yang plural dan terdiri dari berbagai macam ciri khas, identitas serta pola pikir yang berbeda, tentunya setiap individu tidak terlepas dari sebuah persoalan. Hal yang sama juga terjadi dalam tubuh gereja yaitu pendeta sampai pada jemaat-jemaatnya. Melihat akan pentingnnya pengaruh konflik secara internal dalam perubahan dan perkembangan pribadi tiap jemaat maka menjadi penting juga untuk melihat peran dari Pendeta Rutan terhadap proses rekonsiliasi di dalam Rumah Tahanan Kelas IIB Kota Kupang. Metode pengumpulan data yang digunakan dalam penulisan ini yaitu metode observasi dan wawancara. Teknik wawancara yang digunakan adalah semi terstruktur. Teknik analisis data yang digunakan dalam penelitian ini adalah analisis kualitatif model interaktif. Penelitian ini dilakukan di Kota Kupang, NTT khususnya di Rumah Tahanan Kelas IIB Kota Kupang. Secara garis besar dalam penelitian ini terdapat peran pendeta secara pribadi dalam proses rekonsiliasi, peran pendeta melalui pembentukan imamat am atau presbiter, peran pendeta melalui proses program asimilasi dan integrasi serta peran pendeta dalam melakukan internalisasi kepada jemaat dalam proses pelayanan. Keseluruhan peran pendeta dalam rekonsiliasi ini sangat penting dalam hal meningkatkan kesadaran akan pentingnya tanggung jawab jemaat dalam menghadapi konflik internal setelah masa tahanan

Upaya pemimpin yayasan dalam mencetak generasi islami di Yayasan Al-Kautsar Riung Bandung

Pendidikan merupakan suatu cara yang dilakukan untuk mengembangkan potensi yang terdapat dalam diri dan tidak dapat dipisahkan dalam kehidupan manusia. Pendidikan Islam yang dilakukan baik secara formal maupun non-formal merupakan pendidikan yang menonjolkan corak ajaran Islam yang bertujuan untuk mencetak generasi Islami. Sekarang, generasi Islam semakin menjauh dari Al-Quran dan Pendidikan Islam. Mereka memilih kecenderungan ke dalam hal-hal seperti membaca koran, majalah, komik, bermain media sosial dari pada mempelajari Al-quran dan belajar ilmu agama. Penelitian ini bertujuan untuk mengetahui upaya, implementasi program yang dilaksanakan, tingkat keberhasilan, dan faktor yang mempengaruhi keberhasilan pemimpin yayasan dalam mencetak generasi Islami di Yayasan Al-Kautsar Riung Bandung. Penelitian ini menggunakan pendekatan kualitatif dengan metode deskriptif kualitatif yang artinya penelitian yang dilakukan bertujuan untuk mendeskripsikan atau menggambarkan fakta-fakta secara sistematis dan akurat mengenai populasi yang diteliti. Upaya pemimpin Yayasan Al-Kautsar dalam mencetak generasi Islami di Yayasan Al-Kautsar Riung Bandung sudah cukup baik, hal ini dibuktikan dengan pembentukan dan implementasi program-program yang mengarah ke pembentukan generasi Islami. Adapun upaya yang dilakukan yaitu siswa/santri yaitu dapat membaca Al-Quran dengan baik dan benar, memahami makna dalam Tafsir Al-Quran, mengimplementasikan nilai-nilai agama, melaksanakan shalat 5 waktu, memiliki adab yang baik, berakhlakul karimah, dan memiliki pemahaman yang baik mengenai pelajaran PAI di Sekolahnya. Keberhasilan ini tentunya dipengaruhi oleh beberapa faktor yang berasal dari internal dan eksternal. Dalam penelitian ini dapat disimpulkan bahwa upaya pemimpin yayasan dalam mencetak generasi Islami sudah optimal dilakukan dan cukup baik. Namun, tetap selalu dilakukan evaluasi dalam rangka memperbaiki dan meningkatan capaian yang sudah ada

Energy and economic losses caused by dust on residential photovoltaic (PV) systems deployed in different climate areas

Results of the study revealed that when dust impinged on the surface of the PV modules, monthly maximum power output of a 1.5 kWp system in Perth, Australia and a 50 Wp system in Nusa Tenggara Timur (NTT), Indonesia decreased, on average, by about 4.5% and 8%, respectively. Economic modelling showed that, the cost of production per kWh lost due to dust exhibited by these systems were A$0.26/kWh and A$ 0.15/kWh, respectively. Comparison of the cost of energy losses and maintenance revealed that, the Perth system would require manual cleaning in October while the system in NTT would require cleaning in August and October. Although the saving in production losses is not economically significant, this cleaning schedule was recommended, particularly for small systems in NTT since the extra output can have a significant effect on the quality of life in remote villages. The key finding was that higher dust de-rating factors and more cleaning activity may be more appropriate for PV systems deployed in tropical climate areas than that in temperate climate regions. It is recommended that PV system Standards that use the 5% performance de-rating factor due to soiling are reviewed and consideration given to climate-dependent de-rating factors

Seasonal effect of dust on the degradation of PV modules performance deployed in different climate areas

The aim of this study is to investigate the seasonal effect of dust on the degradation of PV modules deployed in two different climate areas, Perth, Western Australia, a temperate climate region and Nusa Tenggara Timur (NTT), Indonesia, a tropical climate region. Results revealed that PV performance varied with season. In Perth, the performance of PV modules which was maximal in the beginning of summer decreased significantly at the end of the season. The performance then increased back approaching the initial position at the end of autumn and reached a peak at the end of winter. Similar reduction to the summer’s performance was accounted by the modules at the end of spring. Meanwhile, in NTT, the performance of PV modules was maximal in the beginning of wet season, dropped slightly at the end of the season and decreased significantly at the end of dry season. Degradation of all modules in the two sites was more affected by dust compared to the non-dust related factors. The degradation is important information for future PV design in both areas, especially in NTT which accounted greater values than the typical dust de-rating factors

Institutional Effectiveness and Inclusions: Public Perceptions on Indonesia’s Disaster Management Authorities

Disaster risk events always have impacts on disaster losses in terms of the sustainability. The phenomena of natural hazards continue to threaten the social and economic livelihoods of the community, ─ while policies and stipulated regulations for mitigating disaster risks reduction (DRR) endlessly become polemics both in national and local government institutions. The study was conducted to address public perceptions on the effectiveness of Indonesia’s Disaster Management Authorities in managing DRR across the archipelago. Relying on the coproduction principle, the author conducted a case-study through in-depth interviews and literature studies to gain public insights, including related encountered situations ─ revealing perceptions on the track-records of the performance of disaster management authorities in a SWOT analysis. The results indicated that both national and local disaster management authorities respectively are less effective due to the lack of effective communication, coordination, collaboration, and synchronization in managing DRR. Moreover, the scarcity of existing potential leaderships for decision makings through vertical and horizontal negotiations, ─ and lack of persuasive approaches for communities’ engagement at all risk cycles. The study highlighted the importance of reforming the status of national disaster management authority ─ thus, it is more powerful in functioning to command, monitor, and control the lower disaster risk institutions and be able to synergize implemented policies with other government institutions. The study also suggested increasing coproduction through public-private partnerships and philanthropies to upgrade innovations, education and training, also psychological healings as a recovery process for greater sustainable development

Keterlibatan Ayah dalam Meningkatkan Gizi Anak: Tinjauan Sistematis: Fathers' Involvement in Improving Children's Nutrition: A Systematic Review

Gizi anak masih menjadi tantangan utama di banyak negara berkembang, termasuk Indonesia. Meskipun berbagai penelitian menunjukkan bahwa ayah memiliki peran penting dalam mendukung kesehatan dan perkembangan anak, keterlibatan mereka dalam aspek gizi anak sering kali diabaikan. Tinjauan sistematis ini bertujuan untuk memahami berbagai bentuk keterlibatan ayah dalam pemenuhan gizi anak, baik secara langsung maupun tidak langsung. Tinjauan ini mengikuti pedoman PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) dan melakukan penelusuran artikel melalui basis data PubMed dan Scopus. Pemilihan studi menggunakan kerangka PICO (Population, Intervention, Comparison, Outcome), dengan fokus pada partisipasi aktif ayah dalam praktik pemberian makan anak dibandingkan dengan ayah yang tidak terlibat, serta hasil yang berkaitan dengan asupan dan kualitas makanan anak. Sebanyak 12 studi memenuhi kriteria inklusi, mencakup berbagai konteks budaya dan geografis seperti Afrika, Australia, Amerika Serikat, dan Eropa. Bentuk keterlibatan ayah yang diidentifikasi meliputi membantu pemberian makanan pendamping ASI, berpartisipasi dalam pengambilan keputusan terkait makanan, memberikan dukungan emosional kepada ibu dan anak, serta menjadi panutan dalam kebiasaan makan sehat di rumah. Hasil penelitian menunjukkan bahwa keterlibatan aktif ayah berdampak positif terhadap asupan gizi anak, terutama dalam meningkatkan konsumsi makanan padat gizi seperti buah, sayur, dan makanan berprotein. Namun, masih terdapat hambatan seperti norma gender tradisional, kurangnya pengetahuan gizi, dan kendala sistemik yang membatasi keterlibatan ayah. Faktor yang mendukung keterlibatan ayah meliputi pendidikan gizi yang ditargetkan, pendekatan berbasis keluarga, serta pemanfaatan teknologi untuk penyebaran informasi. Tinjauan ini menekankan pentingnya melibatkan ayah dalam intervensi gizi anak. Melalui kebijakan yang inklusif dan strategi inovatif, keterlibatan ayah dapat ditingkatkan guna memperbaiki status gizi anak dan kesehatan keluarga secara keseluruhan.Child nutrition remains a persistent challenge in many developing countries, including Indonesia. Although evidence shows that fathers significantly influence child health and development, their role in child nutrition is often underestimated. This systematic review aimed to understand the various forms of father involvement in child nutrition, both directly and indirectly. Following PRISMA guidelines, articles were systematically searched from PubMed and Scopus databases. The PICO framework was used to guide study selection, focusing on fathers who actively participated in child feeding versus those who did not, and measuring outcomes related to children’s dietary intake and quality. Twelve studies met the inclusion criteria, encompassing diverse regions such as Africa, Australia, the United States, and Europe. Forms of father involvement identified included helping with complementary feeding, participating in food decisions, offering emotional support, and modeling healthy eating at home. The findings consistently showed that active father participation had a positive impact on children’s nutrition, especially in promoting consumption of nutrient-dense foods like fruits, vegetables, and proteins. However, cultural norms, limited nutritional knowledge, and systemic barriers often restricted father engagement. Supportive factors included nutrition education, family-based interventions, and the use of technology to reach fathers more effectively. This review underscores the importance of including fathers in child nutrition interventions. Addressing cultural and structural barriers through inclusive policies and innovative strategies can enhance paternal involvement, ultimately improving family nutrition and child health outcomes

The Impact of Vegetation on the Performance of Polycrystalline and Monocrystalline Silicon Photovoltaic Modules

The performance of a photovoltaic (PV) module decreases with increasing temperature. An emergent method developed to reduce temperature rise is vegetation that refers to cultivating crops under the shade of PV modules. This study aims to investigate the impact of caisim (brassica chinensis var. parachinensis), a popular tropical vegetable, on the performance of two polycrystalline silicon (pc-Si) and two monocrystalline silicon (mc-Si) PV modules. Initially, electrical parameters, solar irradiation, and temperature of the four PV modules were examined without vegetation. Furthermore, the same management was repeated with a treatment of two PV modules (pc-Si 1 and mc-Si 1) were vegetated and the other two modules (pc-Si 2 and mc-Si 2) were designated as reference modules, left without vegetation. Results of the experiments carried out in clear sunny days and analyzed with a least squares method revealed that, for the modules of the same technology, the efficiency of pc-Si 1 (vegetated) was higher than pc-Si 2 (reference), whereas mc-Si 2 (reference) outperformed mc-Si 1 (vegetated). Test results on mc-Si technology indicated that there was no contribution of vegetation to lowering temperature of the vegetated PV module, thereby failing to improve its efficiency. This might be related to the design and material of the mc-Si modules which support conductive heat losses. The conduction effect seemed to be more dominant than the evapotranspiration impact which may be low due to the wind and the greater distance between the vegetation and the modules. The results of this research imply that it is necessary to consider the application of vegetation for pc-Si technology for the design and optimization of the performance of solar power plants in Kupang, Indonesia. This research contributes to shining a light on the intricate relationship between PV module performance and vegetation. In a broader scope, this study provides a motivation for future investigations regarding efforts to overcome land competition to produce energy and food