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Thailand has pledged to be carbon neutral by 2050 at the UN Climate Change Conference (COP26). Promoting all-new buildings to be net-zero energy consumption within 2030 is a strategy to achieve the goal. The previous works have revealed that policymakers and related stakeholders’ supportive strategies could significantly contribute to promoting the zero-energy buildings (ZEB) investment. Moreover, another big challenge in improving high-energy-efficient buildings is the high initial cost and uncertainties of the future costs. As far as we know, no studies have investigated an effect of such a change in economic and relevant costs on the financial benefits of the ZEB project in Thailand. Such parameters are a significant barrier to decision-making on ZEB investment. Consequently, the guidance for affordable financial feasibility and supportive measures could significantly promote ZEB projects. This study used sensitivity analysis to assess the variations of future costs, including initial cost, energy price, maintenance & operation cost, interest rate, and discount rate, influencing the project’s NPVs and the global costs of three representative office buildings. The analyses showed that the total cost was strongly sensitive to the investment cost, with a maximum reduction of 15.76% when the investment cost was reduced by 20%. The NPV was significantly influenced by energy price, with the variations ranging from 2.83% to 15.12%. ZEB development in large buildings provided more financial profitability than in small buildings. Finally, the key effective financial parameters and the key persons responsible for supporting financial measures were proposed to promote ZEB project investment in Thailand. The increase in energy prices and the decrease in initial cost, especially the cost of the air-conditioning systems, will increase investment returns. However, such increments in energy price also affect small and low-income enterprises. For future implementations of ZEB, policymakers should investigate suitable measures and financial incentives.

In this study, two polymorphs of bismuth oxide were synthesized via the solution-based route for the aqueous phase glycerol transformation to high valuable compounds with low energy photocatalysis in the presence of hydrogen peroxide as the electron acceptor. The results showed that the hydrogen peroxide was deficient to produce OH•radicals in tetragonal bismuth oxide (β-Bi2O3) photocatalyst because it decomposed very fast to H2O and O2and unoxidized glycerol, resulting in a low glycerol conversion at almost 6.6 times comparing with that of monoclinic bismuth oxide (α-Bi2O3) photocatalyst. Also, more valuable products could be produced with α-Bi2O3 photocatalyst system. In addition, the possible mechanisms of hydrogen peroxide on the low energy photocatalytic performances of both bismuth oxide polymorphs were discussed.

PV power generation challenging in solar intermittency irradiance is a main problem in the system operation. Flexible Power Point Tracking (FPPT) algorithm for a PV and battery energy storage system (BESS) for storing surplus power or supplying lacking power are employed for smoothing the power. In contrast to Maximum Power Point Tracking (MPPT) algorithm that required a large BESS to regulate the dc-link voltage, the proposed FPPT can minimize the utilization of BESS. As a results, the operation of FPPT can reduce for the battery sizing while maintaining the benefit of power regulation under 10% of power ramp-rate. This paper presents a comparison of FPPT and without FPPT applying to the PV system to investigate the performance of the proposed control strategy focusing on the utilization of BESS. The real-time simulation HIL is simulated to verify the effectiveness of the system with an irradiance curve profiles.

Overvoltage is a critical problem of Thailand’ distribution system. The electrical protection device in the distribution system needs to be able to support this level of overvoltage. In the distribution system connecting the Chachoengsao2 substation and the Bang Khla substation, the overvoltage from a ferro resonance phenomenon affects the surge arrester directly. This research studies the effect of the drop-out fuse connection scheme on the voltage and surge arrester using the RMS/EMT Simulation mode in the DIgSILENT program. Normally, the surge arrester withstands a voltage of 1.9 p.u. of the phase voltage. If the overvoltage in the distribution system is higher than the voltage that the surge arrester can withstand, the surge arrester can be damaged. Therefore, it is necessary to study and analyze the drop out fuse insertion pattern that affects the overvoltage in the distribution system to understand the causes of overvoltage problems and their effects on each type of electrical protective equipment.

Des structures liquides telles que des gouttelettes et des limaces existent à l'intérieur des canaux de gaz des piles à combustible à électrolyte polymère dans des applications à basse température. L'efficacité de ces dispositifs électrochimiques dépend de l'élimination efficace de l'eau produite. Les spécifications des canaux de gaz telles que la géométrie de la section, les angles d'angle et les propriétés de mouillabilité de la surface contrôlent sensiblement le processus d'élimination du liquide. Ici, cinq canaux avec différentes géométries de section sont modélisés et le processus de décharge liquide-slug est étudié en utilisant une méthode de volume transitoire de fluide. Le modèle numérique se compose d'un segment du canal de gaz côté cathode avec les conditions de fonctionnement d'une pile à combustible opérationnelle. Les simulations dynamiques d'écoulement en deux phases montrent que les canaux avec une largeur et une hauteur plus petites aboutissent à une distribution d'écoulement appropriée à l'alimentation en gaz. Un canal avec des dimensions de section de 0,5 mm × 0,5 mm entraîne un dégagement GDL (Gas-Diffusion Layer) 35,18 % plus rapide, une expulsion de liquide 29,32 % plus rapide par rapport à d'autres canaux ayant des dimensions 2 à 3 fois plus élevées. Par conséquent, ce canal est recommandé comme la meilleure conception pour améliorer les performances de la pile à combustible. Existen estructuras líquidas como gotitas y babosas dentro de los canales de gas de las celdas de combustible de electrolito polimérico en aplicaciones de baja temperatura. La eficiencia de estos dispositivos electroquímicos depende de la eliminación efectiva del agua producida. Las especificaciones de los canales de gas, como la geometría de la sección, los ángulos de las esquinas y las propiedades de humectabilidad de la superficie, controlan sustancialmente el proceso de eliminación de Aquí, se modelan cinco canales con varias geometrías de sección y se investiga el proceso de descarga de líquido-obstáculo utilizando un método de volumen transitorio de fluido. El modelo numérico consiste en un segmento del canal de gas del lado del cátodo con las condiciones de trabajo de una celda de combustible operativa. Las simulaciones dinámicas de flujo de dos fases muestran que los canales con menor ancho y altura resultan en una distribución adecuada del flujo en la alimentación de gas. Un canal con las dimensiones de sección de 0.5 mm × 0.5 mm da como resultado un aclaramiento de GDL (capa de difusión de gas) un 35.18% más rápido, una expulsión de líquido un 29.32% más rápida en comparación con otros canales que tienen dimensiones 2–3 veces más altas. Por lo tanto, este canal se recomienda como el mejor diseño para mejorar el rendimiento de la pila de combustible. Liquid structures such as droplets and slugs exist inside gas channels of polymer electrolyte fuel cells in low-temperature applications. The efficiency of these electrochemical devices depends on the effective removal of the produced water. The gas channels' specifications like section geometry, corner angles, and surface wettability properties substantially control the liquid removal process. Here, five channels with various section geometries are modeled and the liquid-slug discharge process is investigated using a transient volume of fluid method. The numerical model consists of a segment of the cathode-side gas channel with the working conditions of an operational fuel cell. The dynamic two-phase flow simulations show that channels with smaller width and height eventuate in proper flow distribution at the gas feed. A channel with the sectional dimensions of 0.5 mm × 0.5 mm results in. 35.18% faster GDL (Gas-Diffusion Layer) clearance, 29.32% faster liquid expulsion compared to other channels having 2–3 times higher dimensions. Therefore, this channel is recommended as the best design for improved fuel cell performance. توجد الهياكل السائلة مثل القطرات والرخويات داخل قنوات الغاز لخلايا وقود البوليمر المنحل بالكهرباء في تطبيقات درجات الحرارة المنخفضة. تعتمد كفاءة هذه الأجهزة الكهروكيميائية على الإزالة الفعالة للمياه المنتجة. تتحكم مواصفات قنوات الغاز مثل هندسة القسم وزوايا الزاوية وخصائص قابلية الترطيب السطحية بشكل كبير في عملية إزالة السائل. هنا، يتم نمذجة خمس قنوات ذات أشكال هندسية مختلفة ويتم فحص عملية تفريغ الشظية السائلة باستخدام حجم عابر من طريقة السوائل. يتكون النموذج العددي من جزء من قناة غاز جانب الكاثود مع ظروف عمل خلية وقود تشغيلية. تُظهر محاكاة التدفق الديناميكي ثنائي المرحلة أن القنوات ذات العرض والارتفاع الأصغر تحدث في توزيع التدفق المناسب عند تغذية الغاز. تؤدي القناة ذات الأبعاد المقطعية 0.5 مم × 0.5 مم إلى خلوص GDL (طبقة انتشار الغاز) أسرع بنسبة 35.18 ٪، وطرد سائل أسرع بنسبة 29.32 ٪ مقارنة بالقنوات الأخرى ذات الأبعاد الأعلى 2–3 مرات. لذلك، يوصى باستخدام هذه القناة كأفضل تصميم لتحسين أداء خلية الوقود.

Methyl orange (MO) is an intensely colored compound used in dyeing and printing textile, which contaminates the effluent. Photo-Fenton reaction is one of the advanced oxidation processes (AOPs) which can treat the pollutant to the green products and small molecules. Photo-Fenton process using Fe/TiO2catalyst was applied to decolorization of methyl orange. The Fe/TiO2 catalyst was prepared by using dry impregnation method. Plackett–Burman Full Factorial was applied to identify the significant parameters in methyl orange decolorization. Six factors (i.e. Fe/TiO2 catalyst concentration, initial H2O2 concentration, initial MO concentration, pH, stirring speed, and light intensity) influencing methyl orange decolorization were investigated. The results showed that the regression model for parameter screening was well-fitted with the experiment data, supported by the high R2 of 0.95. The results also showed that Fe/TiO2 catalyst dosage, H2O2 concentration, initial MO concentration, stirring speed, and light intensity were the significant effects (P < 0.05) rather than pH. The assumption means a lot in engineering design involving with the confounding multifactor. It could be seen from the conclusion that Plackett–Burman Full Factorial is a suitable tool for screening a large number of parameters, when the complicating interactions of these parameters are involved. Therefore, the key parameters can be found and properly engineered; thus warranting the treatment efficiency and minimizing the cost. Keywords: Photo-Fenton process, Methyl orange, Fe/TiO2 catalyst, Plackett–Burman Full Factorial Design

Ethanol is becoming the important renewable energy sources in the world which produces from carbohydrate resources. The raw material selection is the important procedure for real industrial production. The effect of biomass structural composition in feedstock on ethanol production is therefore needed to explore for feedstock selection. According to the previous research studies, the fermentation process includes pre-treatment and fermentation of sugar to ethanol. This study focuses on the simulation of raw material variation in ethanol production especially the structural composition of carbohydrate that contains three main components, cellulose, xylan, and lignin, in the fermentation section. The simulation model is validated by the data of previous study information with small deviation. The mixture design method is used for result interpretation and analysis. From the design of experiment, there are 14 scenarios and the selected response parameter is the mass fraction of ethanol in outlet stream of fermentation section. From the results, the maximum mass fraction of ethanol in outlet stream is in the scenario which has a large amount of cellulose and xylan fractions. This is because the conversion of reaction in the fermentation reactor mostly consumes cellulose and xylan to produce glucose and xylose, respectively, and converts them into ethanol product. From the overall result of this study, the important of raw material selection in ethanol production is illustrated.

L'une des meilleures façons de consommer de manière optimale l'énergie thermique des combustibles fossiles est d'utiliser des systèmes combinés de refroidissement, de chauffage et d'alimentation (CCHP). Dans de tels systèmes, en recyclant la chaleur perdue des gaz chauds générant simultanément de l'énergie, de la chaleur et de la réfrigération à partir de la combustion, ainsi que de l'eau et de l'huile de refroidissement dans les systèmes de production d'électricité, l'efficacité globale de l'utilisation de l'énergie du système peut être augmentée à plus de 85 %. L'analyse et l'optimisation des systèmes CCHP sont principalement conformes à la réduction des coûts d'exploitation sans tenir compte de la réduction des émissions et de l'utilisation réelle de l'énergie. La présente étude propose un flux d'énergie pour le système CCHP afin de réduire la consommation d'énergie principale en fonction de la demande thermique du bâtiment dans la région de Kerman, en Iran. La méthode a introduit une version développée de l'algorithme de recherche Owl pour augmenter l'efficacité du système CCHP par rapport au système de production de séparation. Les simulations finales déclarent des résultats bien efficaces pour la méthode présentée. Una de las mejores maneras de consumir de manera óptima la energía térmica de los combustibles fósiles es utilizar sistemas combinados de refrigeración, calefacción y energía (CCHP). En tales sistemas, al reciclar el calor desperdiciado de los gases calientes que generan simultáneamente energía, calor y refrigeración a partir de la combustión, así como agua y aceite refrigerante en los sistemas de producción de electricidad, la eficiencia general de utilización de energía del sistema se puede aumentar a más del 85%. El análisis y la optimización de los sistemas CCHP están en su mayoría de acuerdo con la reducción de los costos operativos sin considerar la reducción de emisiones y la utilización real de la energía. El presente estudio propone un flujo de energía para el sistema CCHP para disminuir el consumo de energía principal basado en la demanda térmica de un edificio en el área de Kerman, Irán. El método introdujo una versión desarrollada del algoritmo de búsqueda Owl para aumentar la eficiencia del sistema CCHP en comparación con el sistema de producción de separación. Las simulaciones finales declaran resultados bien eficientes para el método presentado. One of the best ways to optimally consuming fossil fuel thermal energy is to utilize combined cooling, heating, and power (CCHP) systems. In such systems, by recycling heat wasted from hot gases simultaneously generating power, heat, and refrigeration from combustion, as well as water and cooling oil in electricity production systems, the overall system energy utilization efficiency can be increased to more than 85%. Analysis and optimization of the CCHP systems are mostly in accordance to the operating cost reduction without considering the emissions reduction and actual energy utilization. The present study proposes an energy flow for CCHP system to decrease the main power consumption based on a building thermal demand in Kerman area, Iran. The method introduced a developed version of the owl search algorithm to increase the efficiency of the CCHP system in comparison with the separation production system. Final simulations declare well efficient results for the presented method. واحدة من أفضل الطرق لاستهلاك الطاقة الحرارية للوقود الأحفوري على النحو الأمثل هي استخدام أنظمة التبريد والتدفئة والطاقة المشتركة (CCHP). في مثل هذه الأنظمة، من خلال إعادة تدوير الحرارة المهدرة من الغازات الساخنة في وقت واحد لتوليد الطاقة والحرارة والتبريد من الاحتراق، وكذلك الماء وزيت التبريد في أنظمة إنتاج الكهرباء، يمكن زيادة كفاءة استخدام الطاقة الإجمالية للنظام إلى أكثر من 85 ٪. يتوافق تحليل وتحسين أنظمة CCHP في الغالب مع خفض تكاليف التشغيل دون النظر في خفض الانبعاثات والاستخدام الفعلي للطاقة. تقترح الدراسة الحالية تدفق الطاقة لنظام CCHP لتقليل استهلاك الطاقة الرئيسي بناءً على الطلب الحراري للمبنى في منطقة كرمان بإيران. قدمت الطريقة نسخة مطورة من خوارزمية البحث عن البومة لزيادة كفاءة نظام CCHP مقارنة بنظام إنتاج الفصل. تعلن المحاكاة النهائية عن نتائج فعالة بشكل جيد للطريقة المقدمة.