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Today, studies to develop absorption refrigeration cycles that use low and medium temperature cheap and clean energy sources in the field of refrigeration have gained momentum. In this study, analyzes have been made with the assumption that NH3-H2O and LiBr-H2O working fluids are used in the single-effect absorption refrigeration system and the energy required for this refrigeration system is provided by solar energy. For the provinces of Antalya and Kocaeli, which are selected from our two regions with different solar energy potential, the collector areas and collector efficiencies required to operate the system when the absorption refrigeration systems are operated with the vacuum tube collectors supported by solar energy have been calculated separately according to the months. At the end of the study, the solar utilization rates (SF) have been calculated in detail these two different working fluids and compared with each other in order for the analyzed systems to benefit from solar energy in the most economical way. In the SF analysis conducted to utilize solar energy economically, the collector areas found suitable for LiBr-H2O and NH3- H2O fluid pairs for Antalya have been calculated as 65 and 105 m² with SF ratios of 78.4% and 75.2%, respectively. For Kocaeli, the economically feasible collector areas have been calculated as 85 and 135 m² for LiBr-H2O and NH3-H2O pairs with SF ratios of 76.2% and 71.6%, respectively. Turkey has a rich potential in terms of solar energy due to its geographical location, and meeting the increasing energy need for refrigeration with this potential will make a significant contribution to our economy. [ABSTRACT FROM AUTHOR]

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Solar energy power plants play a significant role in meeting the demand for sustainable and clean energy. However, variable weather conditions, seasonal effects, and similar factors can result in the need for energy overproduction to be stored or lead to costs associated with energy deficiency. These situations can result in inefficiencies in solar energy production. The objective of this study is to predict energy production, increase efficiency, and develop more sustainable energy strategies by using machine learning methods with data obtained from meteorological and solar energy panels. This study aims to assess the results achieved by existing models and compare their successes. The Random Forest algorithm, which achieved the highest R² score, also obtained significantly lower values for MSE, RMSE, and MAE. This indicates that the Random Forest algorithm performs the best among the algorithms used in this study. This ranking of success is followed by Decision Trees and K-Nearest neighbors. [ABSTRACT FROM AUTHOR]

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Balkan & Near Eastern Journal of Social Sciences (BNEJSS) is the property of Balkan & Near Eastern Journal of Social Sciences (BNEJSS) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For approximately the last two centuries, countries have turned to alternative energy sources due to environmental pollution and depletion of fossil energy resources, and in this context, "renewable energy" sources have come to the fore. "Solar energy", one of the renewable energy sources, has made great progress in terms of technology and installed power during this period. In Turkey, which is one of the countries where great development has been experienced, Konya province, which ranks first in terms of installed capacity, is increasing its installed power from year to year. With the work carried out in the Karapınar Energy Specialized Industrial Zone and the solar power plants planned to be established, the electricity needs of more than one million residences will be met. This study, which aims to evaluate energy production from solar panels in Turkey through the example of Konya province, was carried out using open sources and data analysis based on qualitative research method. As a result of the study, it was determined that Konya was suitable for establishing solar power plants and the factors that make Konya stand out from other suitable provinces are; It has Karapınar Energy Specialized Industrial Zone, suitable climatic conditions, large and unsuitable for agriculture plains, etc. was determined as. [ABSTRACT FROM AUTHOR]

With the substantial increase in the amount of energy demanded and consumed today, there is also an increase in energy generation from renewable energy sources. Including renewable energy sources in an electrical grid and using them introduces the problem of planning the network in the most economical and efficient way. This thesis addresses the optimal power flow problem, which is one of the power system problems integrated with wind and solar power, both renewable energy sources. The optimal power flow problem is an optimization problem with a nonlinear structure and various constraints, where the best values of control parameters are determined. Additionally, combining the nature of solar and wind energy increases the complexity of the problem. Heuristic search algorithms, which are a type of artificial intelligence technique, are preferred in solving such problems. In this paper, the Triangulation Topology Aggregation Optimizer (TTAO) algorithm was first developed based on distance adequacy balance for the solution of the optimal power flow problem. The developed algorithm was applied to the optimal power flow problem including wind and solar energy sources and compared with the results of different algorithms in the literature. The obtained results clearly show that the proposed algorithm is effective in this power system problem. [ABSTRACT FROM AUTHOR]

Energy storage systems are needed to increase the efficiency of intermittent energy sources such as solar energy. It is important for efficiency to store and use the excess heat as a result of radiation during the hours when the sun's influence is high. In this study, a mixture of stones and metal parts of different sizes was created as an energy storage material. This material was used in the thermal storage unit of the 2nd section of a solar dryer consisting of two identical sections with thermal insulation between them and compared with part 1 which was without thermal storage system. As the agricultural product to be dried, Sason Strawberry, which starts in March, April, and continues until November and December, depending on the weather conditions, was preferred and the drying parameters were examined in October under the conditions of Batman Province. Experiments were carried out between 09.00-15.00 in the sun, between 15.00-17.30 in the shade and after 17.30 after sunset, using the thermal storage heat. The experiments were carried out at 3 different fan speeds as 3.5 m/s, 2.5 m/s and 1.5 m/s. During the experimental studies, drying was carried out at temperatures ranging from a maximum of 61 °C to a minimum of 18 °C in the drying cabinet without using the thermal storage system, and at temperatures ranging from a maximum of 53 °C to a minimum of 19 °C in the drying cabinet using the thermal storage system. [ABSTRACT FROM AUTHOR]

With the increase in the use of solar energy, the investigation of the failures that cause the decrease in efficiency and loss in production is increasing day by day. It is extremely beneficial to conduct on-site testing of solar systems in order to evaluate the plant's actual performance and identify potential problems. There are important methods for on-site and fast detection of failures. In this study, the failures in the panels were analyzed using the Electroluminescence test, which is one of the most reliable methods for the detection of micro-cracks, and 11 failures were detected as a result of the EL imaging. The EL test, which is the most reliable method for detecting micro-cracks, has been compared with infrared thermal images and its superiority has been proven. Energy losses were prevented by intervening in the field with rapid fault detection. [ABSTRACT FROM AUTHOR]

In this research paper the feasibility of renewable-powered, selfsufficient university campuses was explored by conducting a technoeconomic analysis of standalone PV-Battery systems for the buildings of Izmir Institute of Technology (IZTECH) in Izmir, Turkey. Given the high energy demand and dependence on fossil-based grids by universities, integrating renewables becomes important for minimizing carbon footprints. In this study the campus's solar potential was focused and the techno-economic feasibility of grid-independent operations provided by PV-battery systems was evaluated. Four scenarios were investigated: (i) maximum PV installation for each building (MPVB), (ii) maximum PV installation for the entire campus (MPVC), (iii) necessary PV installation for self-sufficiency of each building (NPVB), and (iv) necessary PV installation for self-sufficiency of the whole campus (NPVC). The first two scenarios considered the maximum achievable rooftop PV installation while the latter two included additional PV installation to cover all electricity needs. For all scenarios both lead-acid and Liion batteries were considered. Mathematical models were developed using PVSol and TRNSYS software, and technoeconomic analysis was conducted using Levelized Cost of Energy (LCOE) and Net Present Value (NPV) methods. It was found that the NPVC scenario with lead-acid batteries is the most favorable, as it minimizes battery utilization by enabling more PV installation and facilitating energy transfer between buildings. Additionally, the research showed that off-grid PV-battery systems are economically less feasible compared to on-grid counterparts, primarily due to the high cost of batteries. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of International Journal of Economic & Social Research is the property of Abant Izzet Baysal University, Faculty of Economics & Administrative Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The importance of energy in the world is increasing day by day. Most of the countries’ energy needs are met by fossil fuels. Due to the depletion of fossil fuels, their increasing prices and the damage they cause to the environment, researchers have turned to alternative energy sources. The demand for renewable energy sources as alternative energy has increased significantly in recent years. Solar energy is one of the most popular and widely used energy sources among renewable energy sources all over the world. For this reason, efforts are being made to increase the use of solar energy in Türkiye and European countries. Although the amount of solar radiation in Türkiye is high, it has not reached the expected levels. In this study, the payback periods (PBP) of a 1 MW solar power plant (SPP) connected to the grid between Türkiye and European countries were compared. It is assumed that the compared countries use monocrystalline solar panels with an efficiency of 22.6% at their specific solar radiation values. Additionally, due to the impact of the Russia-Ukraine war on energy prices, the PBP of the SPP was determined based on two scenarios. According to the results, in the first scenario, the highest PBP is in Karaman with 2.75 years, followed by Türkiye with 3.17 years. PBPs in Spain, France and Germany are calculated as 3.6, 5.6 and 5.7 years, respectively. In second scenario (after the Russia-Ukraine war), the highest PBPs were determined as Germany with 2.22 years and France with 3.27 years. PBPs in Spain, Karaman and Türkiye were determined as 2.41, 2.75 and 3.17 years, respectively.

Fresh water is one of the most important resources consumed. However, droughts due to global climate change, rapid population growth increasing construction sector activities and the lack of importance to protect freshwater resources during these activities increase the problems related to water. This study aims to raise awareness among people about the protection of freshwater resources. For this purpose, a software and hardware-supported system has been developed to obtain fresh water by cooling and condensing the humidity in the air with the help of thermoelectric modules and fans. The developed system can automatically become active or passive according to the weather conditions and uses less energy than its counterparts. The system, which can also operate independently of the grid with solar energy, can also purify the water obtained by producing ozone gas with the effect of static electricity on the surface where water droplets form and make it drinkable.

Dünya nüfusundaki meydana gelen artışlar, enerjiye olan talepleri de doğrudan etkilemektedir. Nüfus artışı ile doğrudan etkilenen enerji taleplerine karşı tepki verebilmek ve sürdürülebilir bir gelecek sağlamak amacıyla farklı enerji kaynakları arayışları ortaya çıkmaktadır. Son zamanlarda popüler bir hale gelen yenilenebilir enerji kaynaklarının en temeli olan güneş enerjisinden elektrik üretimi ve ısıl uygulamalar ilerlemeye devam etmektedir. Bu çalışmada güneş enerjisinden ısıl enerji elde etmek amacıyla kullanılan güneş enerjili hava ısıtıcıların performansının arttırılması amaçlanmış ve farklı emici yüzeylere sahip güneş enerjili hava ısıtıcısı modelleri geliştirilmiştir. Geliştirilmiş olan bu modellerin analizleri Hesaplamalı Akışkanlar Dinamiği (HAD) yaklaşımı ile gerçekleştirilmiş ve sonuçlar değerlendirilmiştir. Başlangıçta geleneksel düz emici plakalı güneş enerjili hava ısıtıcısı modellenmiştir. Daha sonra düz plakaya sırasıyla 2, 4 ve 8 adet delikler eklenmiş ve aynı şartlar altında sistem analizleri gerçekleştirilmiştir. Yapılan bu analizler sonucu benzer oranlarda basınç düşüşleri görülmüş ve hava akış hızları oldukça yakın oranda azalmıştır. Bunun yanı sıra giriş ve çıkış noktası arasındaki sıcaklık farkları düz plakalı, 2 delikli, 4 delikli ve 8 delikli model için sırasıyla 12,6℃, 10℃, 13,5℃ ve 16,2℃ olarak elde edilmiştir. Elde edilen sonuçlara bağlı olarak delik sayısı ile sistem performansında arttığı ve oluşturulan deliklerin türbülans etkisi yaratarak ısı transferini önemli ölçüde iyileştirdiği gözlemlenmiştir.

Sera etkisi nedeniyle, iklim değişiklikleri gün geçtikte olumsuz etkilerini artan bir şekilde dünyamızda hissettirmeye başlamıştır. Dolayısıyla, fosil kaynaklı yakıt kullanımını azaltmak için güneş ve rüzgâr gibi temiz enerji ve kısıtlı olan su kaynaklarını tasarruflu kullanmak artık hayati bir değer taşımayı geçmiş durumdadır. Bu çalışmanın amacı, Eskişehir iklim şartlarında özellikle tarımsal sulamanın yapıldığı zaman periyodunda; güneş ve rüzgâr enerji sitemlerinin enerji üretim performanslarının ve sulama enerji etkinliklerinin araştırılmasıdır. Projede sistemlerden elde edilen enerji kullanılarak sulama kuyularından çıkarılan su, 350 ton kapasiteli havuzda depolanmakta ve sulamanın gerektiği zamanlarda kullanılmaktadır. Projenin sonuçlarına göre; sistemlerin 1 kWe kurulu gücün üretmiş olduğu enerji; rüzgârda 974 kWh/kWe, Güneşte ise 1.357,74 kWh/kWe olarak gerçekleşmiştir. Sistemlerin geri kazanım (kendini amorti) süresi, rüzgâr enerjisi sisteminde 12,5 yıl, PV güneş enerjisi sisteminde ise 7,1 yıl olarak hesaplanmıştır. Maliyet analizi açısından; sulama suyunun temininde alternatif enerji kaynakları olarak rüzgâr enerjisi, PV güneş enerjisine nazaran 1,87 kat daha pahalı olarak elde edilmiştir. Sonuç olarak; gerek birim enerji maliyeti ve gerekse kurulum ve bakım kolaylığı yönünden PV güneş enerjisi sistemi daha avantajlı olarak öne çıkmıştır.

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the optimum panel tilt angles were determined monthly in order to benefit from solar energy more effectively for solar energy applications to be carried out in Iğdır province. For this purpose, the monthly average daily total solar radiation (HT) values on the solar panels were calculated according to the tilt angle of the panel. The tilt angle was changed from 0° to 90° in 1° increments for each month. The angle giving the highest HT value in each month was taken as the optimum angle. Then, the HT values at monthly optimum angles and the HT values obtained when the panels are placed horizontally, with latitude angle, latitude angle ±15° and seasonal average optimum angle were compared. While the optimum angle was obtained as 0° in June, it was observed that the optimum angle was 58° in January and December. Placing the panels with monthly optimum angles provided 0.02% to 55.61% more solar radiation to reach the surface compared to other conditions. Compared to the latitude angle, an energy gain of 13.35%, 20.89% and 17.46% was achieved in May, June and July, respectively. The lowest solar radiation gain was obtained in October, compared to the seasonal average optimum angle, and the highest gain was obtained in January, compared to the placing horizontally throughout the year. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fotovoltaik (PV) modüllerin en küçük birimini oluşturan güneş gözeleri güneş enerjisini doğrudan elektriğe dönüştürürler. Ancak dönüştürülen elektrik enerjisi gelen enerjisinin %13 ile %20’si arasında değişmektedir. Gelen güneş enerjisinin bir kısmı geri yansımakta geri kalanı ise termal enerjiye dönüşmektedir. Bu nedenle PV modül sıcaklıkları yükselmekte ve PV modüllerin verimleri düşmektedir. Güneş enerjisinden üretilen gücü arttırmanın yollarından biri PV modül sıcaklığını termoelektrik (TE) jeneratörler yardımıyla elektrik enerjisine dönüştürmektir. Bu çalışmada PV – TE güç üretim sistemlerinde yapılan seksen farklı literatür çalışması derlenmiştir. PV-TE sistemler beş grupta sınıflandırılmıştır. Bunlar geleneksel, yoğunlaştırmalı, faz değiştiren malzeme entegreli, ekonomik değerlendirmeler ile güç düzenleme ve kaydetme birimleridir. Özetle geleneksel PV-TE sistemlerdeki sıcaklık ve güç sınırlamalarını ortadan kaldırmak için yoğunlaştırılmış sistemlere geçiş olduğu görülmekle birlikte ve yeni teknikler geliştirilmeye çalışılmaktadır. PV-TE sistemlerin performansı geleneksel PV sistemlerden iyi olsa bile TE modül maliyetinin yüksek olması ve düşük verimliliği bu sistemlerin rekabetçi olmasını kısıtlamaktadır.

Copyright of Anadolu Tarım Bilimleri Dergisi is the property of Ondokuz Mayis Universitesi, Ziraat Fakultesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of International Journal of Agriculture & Wildlife Science is the property of International Journal of Agriculture & Wildlife Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dicle University Journal of Engineering / Dicle Üniversitesi Mühendislik Dergisi is the property of Dicle Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering & Architectural Faculty of Eskisehir Osmangazi University / Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi is the property of Eskisehir Osmangazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to the depletion of fossil fuel resources and environmental concerns in recent years, the share of renewable energy resources in current energy production has been increasing. Wind and solar energies, which are among the renewable energy sources, stand out because they are clean, sustainable, and environmentally friendly energy sources. Wind and solar energy potential varies considerably according to meteorological conditions. Annual average wind speed shows a decreasing trend (22%) from 2018 to 2020. In similar way, wind energy power P also shows a decreasing trend (50%) at the same period during the last five year. Annual average wind speed and total wind energy potential are almost two - three times more in Aqaba than in Amman. Results show more wind speed and wind energy potential have been observed in Aqaba during the last two year at the study period. The variable and difficult control of wind speed and solar radiation cause some problems in terms of power quality, production consumption balance and reliability in solar and wind energy systems. Therefore, during the installation and operation of wind and solar energy systems, it is very important to know and predict the wind speed and solar radiation characteristics of the regions where the systems are installed. Definition of the best places to establish the renewable energy farms and power plants will reduce the cost of electricity at study areas in Jordan. [ABSTRACT FROM AUTHOR]

In this study, a photovoltaic system is simulated for maximum power point tracking using an artificial neural network. The interest in photovoltaic systems is increasing with inadequacy of fossil resources and rise in demand for energy. The variation of photovoltaic system performance depending on environmental conditions reduces efficiency. It is possible to prevent this by reaching maximum power point. Many techniques have been developed to operate system at maximum power point. With the spread of artificial intelligence, smart systems have started to be used in determining maximum power point. Artificial neural networks are intelligent systems that have the ability to learn, generalize and make decisions. In this study, maximum power point is determined with an artificial neural network whose inputs are temperature and radiation. The system was simulated in MATLAB/Simulink environment. A total of 1000 data were used in training of network in which Levenberg-Marquardt algorithm was used, 70% in training, 15% in validation and 15% in testing stages. It was observed that power of photovoltaic panel decreased from 225.1W to 46.9W, and power of boost converter from 220.9W to 45.75W when radiation was reduced from 1000W/m² to 200W/m² at regular intervals. When temperature was increased from 25°C to 45°C at regular intervals, it was determined that power of photovoltaic panel decreases from 225.1W to 194.6W, and power of boost converter from 220.9W to 190.7W. At constant radiation (1000W/m²) and temperature (25°C), system has the highest efficiency value of 98%. At constant temperature and different radiation conditions, it was seen that efficiency decreased as radiation value decreased. Similarly, under constant radiation and different temperature conditions, temperature increase caused a decrease in efficiency. The results show that photovoltaic system with artificial neural network based maximum power point tracking reaches maximum power point under changing environmental conditions. [ABSTRACT FROM AUTHOR]

Energy is crucial for economic, industrial, and social development. The increase in energy consumption is steadily rising. Fossil fuels, which cause greenhouse gas emissions, air, water, and soil pollution, are being replaced by sustainable and environmentally friendly renewable energy sources. Solar energy, which is the basis of renewable energy sources, can be used in both electricity and thermal energy production. In this study, the use of solar energy applications for meeting the electricity and heating needs of a two-person household under Ankara's climate conditions was examined, and an environmental analysis was conducted. The amount of energy that will be obtained by using photovoltaic panels, vacuum tube U-pipe solar collectors, and photovoltaic thermal panels separately and together was calculated. In addition, the effect of using Al2O3+CuO hybrid nanofluid in photovoltaic thermal panels as a working fluid on thermal energy transfer was investigated. As a result of the study, it was calculated that 11 panels with a power of 325 W would be required for meeting the energy demand with only photovoltaic panel use, and 7 panels with 300 W electricity and 600 W thermal power would be required for meeting the energy demand with only photovoltaic thermal panel use. Moreover, it was observed that using Al2O3-CuO hybrid nanofluid in photovoltaic thermal systems instead of pure water increased efficiency by 19.41%. It is recommended that the use of solar energy to meet energy needs will be both an economic solution by using a domestic energy source and an environmental solution by reducing greenhouse gas emissions, addressing the increasing natural gas problem in the world. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Architectural Sciences & Applications (JASA) is the property of Journal of Architectural Sciences & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hacettepe University Journal of Economics & Administrative Sciences / Hacettepe Üniversitesi Iktisadi ve Idari Bilimler Fakültesi Dergisi is the property of Hacettepe University, Faculty of Economic & Administrative Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Sakarya University Graduate School of Business Journal (SAUGSB-J)Sakarya Üniversitesi İşletme Enstitüsü Dergisi is the property of Sakarya University Journal of Business Administration Institute (SAUIED) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The human population in the world and in our country is constantly increasing. As a natural consequence of this increase, consumption is increasing. At the beginning of the increasing consumption is the need for energy. Many of the limited and decreasing energy resources on earth cause harm to the planet with their use. Thanks to these preferred environmental and sustainable energy sources, a reduction in environmental pollution and a slowdown in global warming are achieved. Solar energy is one of these environmental sources. In this study, a system design and theoretical analysis have been made to meet the heating and electrical energy needs of a house designed with a hybrid heat pump with PVT and environmentally friendly CO2 fluid. In the first stage, the heating energy need of the house designed in the study was determined. Afterward, the thermal and electrical analyzes of the PVT were modeled. Finally, the thermodynamic analysis of the heat pump was carried out. As a result of these analyzes and determinations made specifically for the designed system, findings in many parameters were obtained by comparing the system with both CO2 fluid and different fluids. The obtained findings are given in the thesis in graphic and chart formats comparatively. [ABSTRACT FROM AUTHOR]

Güneş destekli hava ısıtıcıların çok yaygın kullanım ile birlikte ısı transferi verimlerinin düşük olduğu bilinmektedir. Bu konuda çeşitli çalışmalar yürütülmektedir. Yapılan bu çalışmada yutucu plaka üzerine kare kesit yapay pürüzlülük oluşturularak tasarlanan bir güneş destekli hava ısıtıcısının sayısal analizi yapılmıştır. Kütle, momentum ve enerji korunumu denklemlerinin sayısal simülasyonu, yaygın kullanılan hesaplamalı akışkanlar dinamiği yazılımı olan ANSYS Fluent ile sonlu hacimler metodunu kullanarak türbülanslı, zorlanmış konveksiyon ısı transferine maruz kalan tam gelişmiş akış için 2-boyutlu olarak yapılmıştır. Yutucu plaka üzerine 1000 W.m-2 sabit ısı akısı uygulanarak 4 farklı Reynolds sayısında (4000, 8000, 12000 ve 16000) ve 3 farklı pürüzlülük oranında (5,33, 10,67 ve 16,00) akış oluşturulmuştur. Reynolds sayısına bağlı olarak Nusselt sayısı, sürtünme faktörü değişimi ve akışkan çıkış sıcaklığı irdelenmiştir. Ayrıca, Reynolds sayısının ve pürüzlülük oranının ısı arttırma oranına etkisi incelenmiştir. Maksimum ısı arttırma oranı (Re=800 ve P/e=16’de) 1,20 olarak hesaplanmıştır. Yutucu plaka üzerinde yapay pürüzlülükler oluşturularak laminer alt tabakada türbülans sağlanması ile ısı transferinin arttırıldığı görülmüştür. Akışkan giriş ve çıkış sıcaklık farkı 4 K civarında bulunmuştur.

Trombe wall is an inexpensive passive heating design method used for storing and utilizing solar energy to increase indoor temperature without relying on any mechanical system that requires additional energy. Most recent studies concerning solar wall configuration and energy efficiency have been conducted by using computational fluid dynamics. One reason for this is because semi-transparent and opaque boundaries are provided in simulating wall and glazing surfaces around the fluid domain and solar heat flux energy are allowed in through semi-transparent boundaries. However, finite element method programs employ solid and shell elements as opaque walls that transmit the energy into the domain. In this study, numerical heat flux analysis of a Trombe wall system, which was built for a previous experimental study, has been performed and numerical and experimental analysis results have been verified. According to the simulation studies, heat transfer analysis results are obtained in a good agreement with real time measurements when additional solar load calculated due to transmissivity are defined at the surfaces which are expected to be sun exposed. Besides, numerically verified model of the Trombe wall system was used in evaluating energy saving potential of residential buildings for three cities with different climate regions in Turkey.

In this study, a study was carried out on integrating solar assisted systems into heating systems in a building. For the study, an existing building was modeled with the DesignBuilder building energy simulation program. The scenarios were created on the model to determine the number of solar collectors and the capacity of the water tank used in solar assisted heating systems. The primary energy consumption, global costs and payback periods of the scenarios created were obtained by parametric analysis. According to the results obtained, the solution that reduces primary energy consumption the most is SYS20, the solution that reduces the global cost the most is SYS1 and the optimum solution is SYS7. Considering the payback periods, SYS1 was determined as the most appropriate solution to be applied in the study since it was the solution with the minimum payback period. At the end of the study, it was seen that primary energy savings could be reduced by up to 47% with solar energy assisted heating system. Thanks to the study, a reference source for the number of solar collectors and water tank capacity selection in Isparta and provinces with similar climates has been created. [ABSTRACT FROM AUTHOR]

With the increase in the world population, the need for food also increases, and accordingly, the importance of existing agricultural and pasture lands is better understood. While the world countries are making plans to increase the efficiency they get from their existing agricultural areas, the need for energy is increasing rapidly due to factors such as technology and industrialization. In order to meet the increasing energy need, all kinds of energy sources have been used until recently, ignoring the effects on the environment, but the limitation of resources such as coal and oil and the awareness of their negative effects on the environment has accelerated the orientation towards renewable energy sources. In this regard, wind and solar energy come to the fore. However, large lands are required for solar power plants, which creates a negative situation for limited agricultural areas. It is thought that the establishment of agrivoltaik systems or the preference of wind power plants in order to reduce the factors that suppress agricultural areas today, where the importance of agriculture and the need for agriculture are increasing, may benefit agriculture and animal husbandry. [ABSTRACT FROM AUTHOR]

The electricity grid is faced with the problems of insufficient investments, old infrastructure, line losses, low efficiency and energy quality. For this reason, many developed countries have begun to transition to micro and smart grid structures in which generation, consumption and storage are concentrated within a region. In this process, integrating local power generation resources into micro-smart grids will help energy supply. Among renewable energy sources, wind and solar energy are common and have a high application potential. In terms of local application, vertical wind turbines do not require towers, have low maintenance costs, and do not require a rudder system. These advantages increase when it becomes a hybrid system with solar energy. Especially in buildings where consumption is continuous, it is thought that these systems will contribute to the diversity in energy generation, even at a certain rate in the future. In this study, building integrated vertical wind turbine-solar hybrid energy systems (VWTS-HES) were examined, technical and economic analysis of the data was made with the HOMER PRO program in order to determine the most suitable renewable energy hybrid system to meet the electrical load, and suggestions were made in this direction. According to these results, it was concluded that Aktürk VWTSHES installation is the VWTS-HES with the lowest cost and the shortest depreciation period for 7 kW power, which is the monthly average electricity consumption of a family of 4, among the three VWTSHESs examined. In today's conditions, it has been seen that consumers can come together and turn to building-integrated VWTS-HESs so that consumers can contribute to the power system as producing consumers and micro-intelligent grid structures can develop, and VWTS-HES structures can contribute to the diversity of electrical energy generation. [ABSTRACT FROM AUTHOR]

Copyright of Dicle University Journal of Engineering / Dicle Üniversitesi Mühendislik Dergisi is the property of Dicle Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The rapid development of technologies using renewable energy sources is paving the way for new solutions to meet the increasing energy and power needs of the industry. This study investigated the thermal and flow properties of a solar air heater used in food drying in the industry. The optimum efficiency of the solar air heater (SAH) was investigated for two different absorber plate lengths (1400 mm and 1820 mm). The energy and exergy efficiency values of both collectors were compared. ANSYS FLUENT 18.1 was used as a computational fluid dynamics (CFD) numerical analysis program in the study. Analyzes were performed at three different mass flow rates as 0.038-0.054-0.070 kg/s and 3-dimension (3D), respectively. For the accuracy of the CFD analysis, the experimental results with a mass flow rate of 0.038 kg/s were compared with the analysis results. Friction coefficients were calculated from the pressure drop obtained from the analysis. Temperature, velocity, and pressure distribution variations were shown for different times of the day. The highest thermal efficiency was realized at 13:00 at a mass flow rate of 85% and 0.070 kg/s. The thermal efficiency of the collector has increased with higher flow rates. Although the increase in the mass flow through the collector decreased the outlet temperature, the valuable energy amount increased. This study demonstrated that different mass flow rates and absorber plate size significantly affect the thermal efficiency of SAH. [ABSTRACT FROM AUTHOR]

Determining where to install solar panels and power plants is a very complex and difficult to analyze spatial decision-making problem series. In order to solve this series of problems, Multi-Criteria Decision-Making methods integrated into Geographic Information Systems software have been preferred in recent years. This study aims to determine the areas with solar energy production potential in the Kars province. In the research, thematic maps were created for the purpose of processed research by obtaining data from various open sources in order to analyze the determined criteria that affect the location selection of areas with solar energy production potential. Based on the criteria weights calculated by AHP analysis from these maps, suitable areas with potential for solar power plant installation in the province of Kars were mapped in the GIS environment. As a result of the research, an area of 54,581 km2, which is very suitable and suitable for solar power plant installation in Kars province, has been determined and these lands constitute 55 % of the province’s surface area with a total surface area of 10,193 km2. The lands with potential for solar power plant installation in the Kars province show a homogeneous distribution. [ABSTRACT FROM AUTHOR]

Increasing energy demand around the world and meeting this demand from fossil fuels cause negative consequences such as global warming. For reducing the impact of these results, the use of renewable resources is gaining importance. Heating of buildings is a high energy dependent process, thus benefiting from solar energy is advantageous for locations with a long hours of sunshine. Manisa is also advantageous in terms of sunshine duration. One of the solar heating applications is the Trombe wall. In this study, a classical Trombe wall (Type-1) and a different type of Trombe wall (Type-2) were designed and these two types of walls were compared in terms of energy, economic and environmental aspects. During analyzes, the air channel depth and the variation of solar radiation intensity, which are important parameters for Trombe walls, are discussed. As a result of the calculations, the energy efficiency for Type-1 and Type-2 walls was found to be 0,37 and 0,46, respectively, at the optimized operating parameters for January (for 500 W/m2 solar radiation intensity and 0,35 m air duct depth). Again with these parameters, it has been calculated that the indoor temperature rises to the maximum values of 19,6 oC and 21,8 oC for Type-1 and Type-2 walls at 15.00. Economic analysis indicated that payback period of the Type-1 and Type-2 walls are 7,3 and 6,9 years, respectively. It has been calculated that the use of Type-1 and Type-2 walls provides a reduction of 5985,5 kg and 6405 kg in total carbon emissions, respectively. [ABSTRACT FROM AUTHOR]

The software used today, on the estimation of module temperature of photovoltaic systems, seem very important to be analyzed. These estimates are crucial in future techno-economic and environmentally friendly analyses of the systems to reach better achievements for future generations. This is very important to reach lifetime analyses of long-term feasibility to find out payback time and the levelized cost of energy. The present work is based on this issue, to test the module temperature estimation formulas used by four commonly used software models, and to determine the most suitable software for temperature analyses of five different photovoltaic modules in Middle Anatolia. Outdoor truthful long-term testing is the main realistic approach to reach fundamental contemplations. After an introductory basic knowledge, the main materials and methods are discussed to enlighten the analysis. The main methodology is given and further prospects are enlightened. Four well-known software are analyzed using four years of outdoor testing of five different photovoltaic modules. Measured ambient temperature and solar irradiance are used in the categorization of the software estimation performances. PV*SOL appears to be superior at low irradiance and ambient temperature, whereas Helioscope appears to be superior overall. [ABSTRACT FROM AUTHOR]

Even though the performance of photovoltaic/thermal (PV/T) panels had been examined both computationally and experimentally for some time, the thermal models created in earlier research were mostly steady-state models for estimating the annual yields. In this study, the solar thermal collector and photovoltaic (PV) cells are combined to create the PV/T collector, and water-ethylene glycol is utilized as a coolant to lower the temperature of the PV panels. The goal of this study is to analyze a water-ethylene glycol-based PV/T collector numerically. Time-dependent dynamic analyzes were performed using the MATLAB software program. Investigations were also done into how the electrical power produced and the temperatures of the fluid outlet and PV/T surface changed over time. As a result of the annual analysis, the maximum power of PV/T is calculated as 155 W. Also, the maximum surface temperature of PV/T panel's is 56.62°C. [ABSTRACT FROM AUTHOR]