• Energy Research
• physical sciences close
• 7. Clean energy close
• 13. Climate action close
• 6. Clean water close
• 14. Life underwater close

En este trabajo, se ha investigado el impacto de seis capas diferentes de recubrimiento antirreflectante (ARC) utilizando el software de simulación PC1D. La simulación muestra que el rango de 500–700 nm sería adecuado para diseñar un ARCO. Diseñando un ARCO de nitruro de silicio de una sola capa (Si3N4) para una longitud de onda de 600 nm y con un espesor de 74.257 nm, se ha simulado una célula solar de silicio con una eficiencia del 20.35%. Le sigue muy de cerca una célula solar de silicio con una eficiencia del 20,34% con una capa de ARCO de óxido de zinc (ZnO) de 74,87 nm de espesor. Se ha observado un aumento significativo en la eficiencia al aplicar ARC con respecto a no aplicar ningún tipo de ARC. Después de un modelado eficiente de las células solares, se está logrando una eficiencia óptima del 20,67% mediante el uso de la pasivación superficial de SiO2 y la capa de ARCO de Si3N4. Los efectos sobre la tensión, la corriente, la eficiencia fotovoltaica, la reflectividad y la eficiencia cuántica externa debidos a los ARC también están representados en este trabajo. Dans ce travail, l'impact de six couches différentes de revêtement antireflet (ARC) a été étudié à l'aide du logiciel de simulation PC1D. La simulation montre que la plage de 500–700 nm serait appropriée pour concevoir un ARC. En concevant un ARC de nitrure de silicium monocouche (Si3N4) pour une longueur d'onde de 600 nm et une épaisseur de 74,257 nm, une cellule solaire en silicium avec une efficacité de 20,35% a été simulée. Très étroitement suivie par une cellule solaire en silicium à 20,34 % d'efficacité avec une couche d'ARC en oxyde de zinc (ZnO) de 74,87 nm d'épaisseur. Une augmentation significative de l'efficacité a été observée en appliquant L'ARC par rapport à l'absence d'application de tout type d'ARC. Après une modélisation efficace des cellules solaires, une efficacité optimale de 20,67 % est obtenue en utilisant la passivation de surface SiO2 et la couche D'ARC Si3N4. Les effets sur la tension, le courant, l'efficacité photovoltaïque, la réflectivité et l'efficacité quantique externe dus aux ARC sont également représentés dans ce travail. In this work, the impact of six different anti-reflection coating (ARC) layers has been investigated using PC1D simulation software. Simulation shows that the range of 500–700 nm would be suitable for designing an ARC. Designing a single-layer silicon nitride (Si3N4) ARC for 600 nm wavelength and with a thickness of 74.257 nm, a silicon solar cell with 20.35% efficiency has been simulated. Very closely followed by a 20.34% efficient silicon solar cell with 74.87 nm thick zinc oxide (ZnO) ARC layer. Significant increase in efficiency has been observed by applying ARC in respect to not applying any kind of ARC. After efficient solar cell modeling, optimum efficiency of 20.67% is being achieved by using SiO2 surface passivation and Si3N4 ARC layer. The effects on voltage, current, photovoltaic efficiency, reflectivity and external quantum efficiency due to ARCs are also represented in this work. في هذا العمل، تم التحقيق في تأثير ست طبقات مختلفة من الطلاء المضاد للانعكاس (ARC) باستخدام برنامج محاكاة PC1D. تظهر المحاكاة أن النطاق من 500–700 نانومتر سيكون مناسبًا لتصميم القوس. تصميم قوس نيتريد السيليكون أحادي الطبقة (Si3N4) بطول موجي 600 نانومتر وبسمك 74.257 نانومتر، تمت محاكاة خلية شمسية من السيليكون بكفاءة 20.35 ٪. تليها عن كثب خلية شمسية من السيليكون فعالة بنسبة 20.34 ٪ مع طبقة قوسية من أكسيد الزنك بسماكة 74.87 نانومتر (ZnO). لوحظت زيادة كبيرة في الكفاءة من خلال تطبيق القوس فيما يتعلق بعدم تطبيق أي نوع من القوس. بعد نمذجة الخلايا الشمسية بكفاءة، يتم تحقيق الكفاءة المثلى بنسبة 20.67 ٪ باستخدام تخميل سطح SiO2 وطبقة Si3N4 القوسية. يتم تمثيل التأثيرات على الجهد والتيار والكفاءة الكهروضوئية والانعكاسية والكفاءة الكمية الخارجية بسبب ARCs أيضًا في هذا العمل.

Hydrogenated microcrystalline silicon (μc-Si:H) is an important material for high-efficiency multijunction solar cells. Due to its complex microstructural properties, it is difficult to describe the electronic behavior clearly. In this study, we measure opto-electronic properties including the mobility gap of μc-Si:H films in solar cells, as well as physical properties such as the crystalline fraction profile. The height distribution function of the ZnO substrates is obtained by AFM scans, which is used for optical simulation. All the parameters that we obtained from measurements were used as input parameters of a model in the ASA simulator. We obtained a good fit between measurements and simulations.

Abstract In highly developed countries, a significant progress in the use of alternative and clean energy sources has recently been observed. The European Union has implemented a programme to build wind turbines. It is estimated that in the coming years, thanks to the support in tax and credit, the global energy will develop very intensively. Many components of the wind turbines are castings. The basic material used for these castings is ductile iron, which in this particular case must meet high requirements imposed by the operating conditions of wind turbines. Anticipating an increase in customer demand for this type of castings, Krakodlew SA has decided to modernize its foundry using the ability to obtain external financing. The ductile iron manufacturing technology is now being developed and adapted to the specific conditions of the foundry plant, including the melting process yielding cast material with the required chemical composition, the technology of moulding, and the conditions for possible secondary metallurgy, spheroidizing treatment and graphitizing inoculation. The fulfilment of the imposed conditions for the casting production demands the use of advanced casting technologies introduced to the manufacturing process. The development of technology to launch the production of ductile iron castings for the wind power industry was supported by The National Centre for Research and Development (NCBiR). This article presents part of research on the binding kinetics of furan resin sands and choice of their composition for moulds and cores to make heavy castings used as components of equipment for the wind power industry.

Based on the existing acknowledgment that space charge modulates AC and DC breakdown of insulating materials, this investigation promotes the related investigation into the situations of more complex electrical stress, i.e., AC-DC combined voltages. Experimentally, the AC-DC breakdown characteristics of oil impregnated paper insulation were systematically investigated. The effects of pre-applied voltage waveform, AC component ratio, and sample thickness on AC-DC breakdown characteristics were analyzed. After that, based on an improved bipolar charge transport model, the space charge profiles and the space charge induced electric field distortion during AC-DC breakdown were numerically simulated to explain the differences in breakdown characteristics between the pre-applied AC and pre-applied DC methods under AC-DC combined voltages. It is concluded that large amounts of homo-charges are accumulated during AC-DC breakdown, which results in significantly distorted inner electric field, leading to variations of breakdown characteristics of oil impregnated paper insulation. Therefore, space charges under AC-DC combined voltages must be considered in the design of converter transformers. In addition, this investigation could provide supporting breakdown data for insulation design of converter transformers and could promote better understanding on the breakdown mechanism of insulating materials subjected to AC-DC combined voltages.

It is numerically demonstrated in this paper that integrating 2-D arrays of silver (Ag) nanopillars into organic photovoltaic (PV) cells with thin active layers can enhance absorption efficiency of up to 40% over a broad bandwidth of operation. This corresponds to an increase in integrated AM1.5G absorption at normal incidence from 48% to 67%. Broadband enhancement is observed to be insensitive to the polarization of incident sunlight over a wide angle range. It is attributed to the sunlight strongly coupling to waveguide modes of the active layer and being converted to surface plasmon resonant modes localized around nanopillars.

The increasing use of piezoelectric generators to harvest energy from various ambient sources requires the establishment of durability data for piezoelectric materials. In this paper, a d3 mode piezocomposite electricity generating element (PCGE) was tested for its durability under cyclic impact loading. For this purpose, a motor driven lever system was designed to apply constant impact force on PCGEs. To investigate the durability of PCGEs, the output voltage of the PCGEs was observed upon repeated application of an impact force until eventual loss of the generated voltage. The experimental results enabled to determine the number of cycles until which PCGEs can be used without loss of their electricity generation performance with respect to the stress level applied on the PCGEs. At low stress level (around 0.76 MPa or lower), the PCGE showed almost insignificant degradation even after 2 million cycles whereas degradation occurred sooner (after 8 x 10(5) cycles) at higher stress levels (around 0.92 MPa or higher). The effects of impact loading on the durability of the PCGEs were also examined by X-ray photographs of the specimens.

120° phase belt toroidal winding solid rotor induction motor (120°PBTWSRIM) has advantages of simple structure, short end winding, and high overload capacity, thus it has good development prospects. To study the influence of different structural parameters on 120°PBTWSRIM performance, the 2D finite element model is established, and the electromagnetic characteristics are analyzed. The influence of six structure parameters on the average output torque, power factor, and torque ripple are analyzed, which are slot opening width, slot opening height, slot width, slot height, slot radius, and copper layer thickness. It is found that copper layer thickness has a significant effect on the performance of 120°PBTWSRIM. When the copper layer thickness is 0.5 mm, locked average output torque is increased to 2.784 Nm, locked power factor is increased by 64.6%, and locked torque ripple is reduced by 79.7%. Finally, a prototype of 120°PBTWSRIM is built and experimented, the correctness of performance influence analysis is verified by the comparison of results of the simulation and the experiment.

Before lower purity, lower cost silicon (Si) materials, such as compensated Si, can play a role in the terawatt-level (TW) capacity of photovoltaics, a better understanding of the fundamental properties of impurities in compensated Si is essential. In this work, high-resolution photoluminescence (PL) has been used to study the charge carrier radiative recombination through Donor-Acceptor pairs (DAPs) in phosphorus (P) and gallium (Ga) co-doped Si material grown for solar cell applications. The high spectral resolution of our PL system, 0.06 meV, enables us to overcome hitherto prior issues of overlapping spectral lines, giving access to extremely fine structures associated with DA pair (DAP) recombination. Our results confirm the presence of three broad bands and a discrete line structure related to DAP luminescence. The comparison of the discrete line structure due to DAPs recombination in the PL spectra with the theoretically predicted one allows the accurate determination of the Ga ionization energy. Temperature-dependent PL is then used to understand the thermally-induced changes in the DAP luminescence. In particular, we observe that the radiative recombination channel remains active for distant DAPs up to ∼40 K, unlike that for close-range DAPs for which the radiative channel is quenched after only slight increases in the temperature range 10–25 K. Furthermore, the analysis of the temperature dependent changes in the PL intensity of the broad DAP bands up to ∼200 K is used to derive the ionization energy of P donors in compensated Si material. In light of this important information, the significance of using high resolution PL to analyse spectral features in compensated Si is demonstrated.