• Energy Research
• 2021-2025close
• TR close

The purpose of this paper is to research the relation among environmental quality and renewable energy in the RECAI country group. The study used per capita CO2 emission, energy intensity, and Aggregate National Savings as a measure of environmental quality. Other variables used in the study are renewable energy consumption, fossil fuel consumption, GDP per capita, and foreign direct investments. In the study, three different models to see different environmental quality indicators by panel quantile method for 19202090-. According to the results obtained, unlike other models, renewable energy consumption in model 1 positively affects energy intensity in all quantiles. In other words, renewable energy consumption negatively affects environmental quality. In model 1 and model 3, the coefficients of fossil fuel consumption were positive and negative, respectively. Unlike model 2, the coefficient estimates of fossil fuel consumption in model 3 were predominantly negative. Fossil fuel consumption shows a positive effect on environmental quality, which is similar to model 1. Economic growth negatively affects environmental quality in all models. There is a one-way causal relationship from renewable energy consumption to energy intensity and energy intensity to growth.

Abstract Research background: The relationship between the economy and the environment is one of the most frequently encountered issues recently. Today the issue of environmental sustainability is one of the problems faced by countries. Purpose: This study, it is aimed at investigating the relationship between economic and environmental variables. Research methodology: The existence of the environmental Kuznets curve theory, in other words, the inverted U-connection between per capita carbon dioxide emissions, per capita ecological footprint, and per capita GDP in the examples of 10 developing countries is examined. We analyzed annual balanced panel data covering the period 1992–2014 for an inverted U-link between carbon dioxide emissions and ecological footprint and per capita GDP. Westerlund’s cointegration test was applied as a cointegration test. The Common Correlated Effects Mean Group (CCEMG) and Augment Mean Group (AMG) estimator methods were applied for long-term parameter estimation. The Dumitrescu and Hurlin causality test was applied to determine the causal connections. Results: As a result of the study, a positive and significant effect of electricity consumption on carbon dioxide emission was determined in the long term in the model where the ecological footprint is the dependent variable. In the environmental Kuznets curve hypothesis, an inverted U-shaped relationship was determined. That is, the results confirming the existence of the environmental Kuznets curve have been determined. Finally, bidirectional causal links between carbon emissions and economic growth, between carbon dioxide emissions and the square of economic growth, and between carbon dioxide emissions and electricity consumption; It is observed between the ecological footprint and economic growth, between the ecological footprint and the square of economic growth, and between the ecological footprint and electricity consumption. It is expected that this article will make a significant contribution to the literature with the important results obtained by using both an ecological footprint and carbon dioxide emission as dependent variables. Novelty: In this study, unlike other studies, two models were created with both CO2 emissions and the ecological footprint data as environmental variables.

Dünya nüfusunun hızla artmasıyla birlikte gelişen sanayi ve teknolojik gelişmeler ihtiyaç duyulan enerjiyi de arttırmaktadır. İhtiyaç duyulan enerjinin en önemlilerinden bir tanesi elektrik enerjisidir. Elektrik enerjisini elde etmek için birçok farklı kaynak kullanılmaktadır. Kömür, elektrik enerjisi üretiminde dünyada en çok kullanılan kaynaktır. Ülkemizde de yüksek rezerviyle kömür birincil enerji kaynağı olarak karşımıza çıkmaktadır. Ancak son yıllarda artan küresel ısınma meteorolojik ekstrem olayları meydana getirmekte insanoğlunu olumsuz etkilemektedir. Küresel ısınmanın en önemli sebeplerinden biri olarak atmosfere salınan karbon olarak gösterilmektedir. Termik santraller kömürün yüksek sıcaklıkta yakılmasıyla yüksek karbon emisyonu üreten santrallerdir. Bu durum her ne kadar baca filtresi teknolojilerinin gelişmesiyle birlikte düşük emisyonlu termik santral gelişmelerini arttırsa da kaynağın tükenebilir fosil bir kaynak olması gerçeği ortadadır. Bu nedenle son enerjiyi doğadan sağlamak çevreci ve sürdürülebilir olması açısından önemlidir. Son yıllarda artan yenilenebilir enerji kaynaklarının (YEK) değerlendirilmesi konusunda büyük bir gelişme görülmüştür. Yenilenebilir enerji kaynakları arasında düşük ilk yatırım maliyeti, hızlı kendini geri ödeme süresi ve düşük karbon emisyonuyla hidroelektrik enerji santralleri (HES) dikkat çekmektedir. Ülkemiz su kaynakları açısından oldukça zengin bir ülke konumunda olduğundan sudan enerji konusunda yararlanma açısından büyük bir avantaja sahiptir. Bu çalışmada, termik santrallerle HES’lerin karbon emisyonu üzerine etkileri araştırılmıştır. Bu nedenle çalışmada, Eskişehir il sınırları içerisinde bulunan başka amaçlarla (sulama, taşkın, içme-kullanma suyu) işletilen Porsuk barajının HES’e dönüştürülmesi durumunda üretebileceği elektrik enerjisi ve karbon salınımına etkisi incelenmiştir.

The need for renewable energy is increasing day by day due to different factors such as increasing energy demand, environmental considerations as well as the will to decrease the share of fossil fuel-based generation. Due to their relative low-cost and ease of installation, PV systems are leading the way for renewable energy deployments around the globe. However, there are meticulous studies that need to be undertaken for realization of such projects. Studying local weather and load patterns for proper panel sizing or considering grid components to determine cable and transformer sizing can be named as some examples for pre-installation studies. In addition to these, post-installation impact studies, e.g. accurate harmonic analysis contribution, is more important to ensure safe and secure operation of the overall system. These steps need to be taken for all PV installation projects. The aim of this study is to show a step-by-step analysis of the effect of a real PV system on the network and to improve the prediction and give a new perspective to the harmonic estimation by using the hourly temperature and radiation data together. At the first phase of the study, a detail real-time 250 kW PV system was modeled for real university campus, and then harmonic estimation based on hourly solar irradiation and hourly temperature was performed with artificial neural networks (ANN) and nonlinear autoregressive exogenous (NARX). The accuracy of the prediction made with ANN was 0.98, and the accuracy of the prediction made with NARX was 0.96.Researchers in PV sizing and control field as well as engineers in power quality area would find these findings beneficial and useful. Use of ANNs and NARX for such analysis indicates the trend in this field that can be targeted by new research projects.

In today's globalized world, rapid depletion of natural resources, increased air and water pollution, deforestation and climate change are major environmental problems for industrial activities. Many industrial activities contribute to environmental pollution by causing these problems. Therefore, it is of great importance to develop environmentally friendly production methods, reduce resource consumption and minimize environmental impacts. The yarn dyeing industry is a sector where natural resources are used intensively and environmental pollution problems are seen. Innovations in this sector aim to make production methods more sustainable. In particular, process reduction is an important step in reducing resource consumption and minimizing environmental impacts. This provides an important opportunity to conserve natural resources and produce environmentally friendly products. Therefore, with the increasing demand for ecological products, it is aimed to develop an environmentally friendly, sustainable and environmentally sensitive process in yarn dyeing. With the new process developed within the scope of the project, a dyeing study was carried out using the natural color of raw cotton yarn. The first bath pre-treatment we apply to raw cotton yarn allows us to make homogeneous dyeing. Thus, it was possible to reduce the need for some chemicals and natural resources that are harmful to nature. The new process developed within the scope of the project is gaining importance in the textile industry due to limited natural resources and increasing environmental problems. The aim of the project is to reduce the use of water, energy and chemicals by eliminating the bleaching step used in traditional yarn dyeing processes and to create an environmentally friendly product platform. In this way, with the increasing demand for ecological and sustainable products, customer expectations can be met and the company's environmental impact can be reduced. In addition, this new process, which saves energy and water, offers the opportunity to gain a competitive advantage by providing cost savings in the textile industry. Therefore, the new process developed sets an example for other businesses in the sector, benefiting both the environment and the operation of the company.

Les développements des systèmes de transport, les changements dans les tendances de consommation et des conditions telles que la COVID-19 ont augmenté à la fois la demande et la charge du transport de marchandises. Étant donné que diverses entreprises transportent des marchandises dans le monde entier pour évaluer la durabilité, la vitesse et la résilience des systèmes de transport de marchandises, des systèmes de mesure de la fluidité des données et du fret sont nécessaires. Dans cette étude, un modèle de prise de décision intégré est proposé pour donner la priorité aux alternatives de mesure de la fluidité du fret. Le modèle proposé est composé de deux étapes principales. Dans la première étape, la méthodologie logarithmique des poids additifs (LMAW) basée sur les normes de Dombi est utilisée pour trouver les poids des critères. Dans la deuxième phase, une évaluation étendue basée sur la méthode de la distance de la solution moyenne (EDAS) avec Dombi onction pour l'agrégation est présentée pour déterminer les résultats finaux de classement des alternatives. Trois alternatives de mesure de la fluidité du fret sont proposées, à savoir ne rien faire, intégrer les activités de fret dans Metaverse pour mesurer la fluidité et former une gouvernance mondiale des activités de fret pour mesurer la fluidité à partir des données disponibles. Treize critères, qui sont regroupés sous quatre aspects principaux à savoir la technologie, la gouvernance, l'efficacité et la durabilité environnementale, et une étude de cas au cours de laquelle un cadre de base est formé pour que les experts évaluent les alternatives compte tenu des critères utilisés dans le processus décisionnel multicritères. Les résultats de l'étude indiquent que l'intégration des activités de fret dans Metaverse pour mesurer la fluidité est l'alternative la plus avantageuse, alors que ne rien faire est la moins avantageuse. Los desarrollos en los sistemas de transporte, los cambios en las tendencias de consumismo y condiciones como el COVID-19 han aumentado tanto la demanda como la carga en el transporte de mercancías. Dado que varias empresas transportan mercancías en todo el mundo para evaluar la sostenibilidad, la velocidad y la resistencia de los sistemas de transporte de mercancías, se necesitan sistemas de medición de datos y fluidez de la carga. En este estudio, se propone un modelo integrado de toma de decisiones para priorizar las alternativas de medición de la fluidez de la carga. El modelo propuesto se compone de dos etapas principales. En la primera etapa, se utiliza la Metodología Logarítmica de Pesos Aditivos (LMAW) basada en normas Dombi para encontrar los pesos de los criterios. En la segunda fase, se presenta una Evaluación extendida basada en el método de Distancia de la Solución Media (EDAS) con Dombi unción para la agregación para determinar los resultados finales de clasificación de las alternativas. Se proponen tres alternativas de medición de la fluidez de la carga, a saber, no hacer nada, integrar las actividades de carga en Metaverse para medir la fluidez y formar una gobernanza global de las actividades de carga para medir la fluidez a través de los datos disponibles. Trece criterios, que se agrupan en cuatro aspectos principales: tecnología, gobernanza, eficiencia y sostenibilidad ambiental, y un estudio de caso en el que se forma un marco básico para que los expertos evalúen las alternativas considerando que los criterios se utilizan en el proceso de toma de decisiones multicriterio. Los resultados del estudio indican que integrar las actividades de carga en Metaverso para medir la fluidez es la alternativa más ventajosa, mientras que no hacer nada es la menos ventajosa. Developments in transportation systems, changes in consumerism trends, and conditions such as COVID-19 have increased both the demand and the load on freight transportation. Since various companies are transporting goods all over the world to evaluate the sustainability, speed, and resiliency of freight transportation systems, data and freight fluidity measurement systems are needed. In this study, an integrated decision-making model is proposed to advantage prioritize the freight fluidity measurement alternatives. The proposed model is composed of two main stages. In the first stage, the Dombi norms based Logarithmic Methodology of Additive Weights (LMAW) is used to find the weights of criteria. In the second phase, an extended Evaluation based on the Distance from Average Solution (EDAS) method with Dombi unction for aggregation is presented to determine the final ranking results of alternatives. Three freight fluidity measurement alternatives are proposed, namely doing nothing, integrating freight activities into Metaverse for measuring fluidity, and forming global governance of freight activities for measuring fluidity through available data. Thirteen criteria, which are grouped under four main aspects namely technology, governance, efficiency, and environmental sustainability, and a case study at which a ground framework is formed for the experts to evaluate the alternatives considering the criteria are used in the multi-criteria decision-making process. The results of the study indicate that integrating freight activities into Metaverse for measuring fluidity is the most advantageous alternative, whereas doing nothing is the least advantageous one. أدت التطورات في أنظمة النقل، والتغيرات في اتجاهات النزعة الاستهلاكية، وظروف مثل COVID -19 إلى زيادة الطلب والحمل على نقل البضائع. نظرًا لأن العديد من الشركات تنقل البضائع في جميع أنحاء العالم لتقييم استدامة وسرعة ومرونة أنظمة نقل البضائع، فهناك حاجة إلى أنظمة قياس سيولة البيانات والشحن. في هذه الدراسة، يُقترح نموذج متكامل لصنع القرار للاستفادة من إعطاء الأولوية لبدائل قياس سيولة الشحن. يتكون النموذج المقترح من مرحلتين رئيسيتين. في المرحلة الأولى، يتم استخدام منهجية لوغاريتمية الأوزان المضافة (LMAW) القائمة على معايير دومبي لإيجاد أوزان المعايير. في المرحلة الثانية، يتم تقديم تقييم موسع يعتمد على طريقة المسافة من الحل المتوسط (EDAS) مع Dombi unction للتجميع لتحديد نتائج الترتيب النهائي للبدائل. يتم اقتراح ثلاثة بدائل لقياس سيولة الشحن، وهي عدم القيام بأي شيء، ودمج أنشطة الشحن في ميتافيرس لقياس السيولة، وتشكيل حوكمة عالمية لأنشطة الشحن لقياس السيولة من خلال البيانات المتاحة. ثلاثة عشر معيارًا، تم تجميعها تحت أربعة جوانب رئيسية وهي التكنولوجيا والحوكمة والكفاءة والاستدامة البيئية، ودراسة حالة يتم فيها تشكيل إطار أرضي للخبراء لتقييم البدائل مع مراعاة استخدام المعايير في عملية صنع القرار متعددة المعايير. تشير نتائج الدراسة إلى أن دمج أنشطة الشحن في ميتافيرس لقياس السيولة هو البديل الأكثر فائدة، في حين أن عدم القيام بأي شيء هو البديل الأقل فائدة.

Elektrik enerjisinin iletimi ve dağıtımında kullanılan teçhizatlardan biri olan güç transformatörlerinde meydana gelebilecek arızaların önceden tespit edilmesi; sistemin ve teçhizatın korunmasını sağlar. Arızaların tespiti için kullanılan yağda çözünmüş gaz analizi ile daha arızanın başlangıç aşamasında arızaya müdahale edilebilmektedir. Arızaların sonucu oluşan bu gazlar transformatör yağından örnekler alınarak yağda çözünmüş gaz analiz (DGA) sistemlerinde değerlendirilir. DGA temel olarak iki şekilde uygulanır. Bunların en bilineni klasik yöntemler ve son zamanlarda geliştirilen akıllı sistemler yani esnek hesaplama yöntemleridir. Klasik sistemlerin arıza belirlemedeki doğruluğunu arttırmak için akıllı sistemler kullanılır. Bu çalışmada gaz oranları kullanarak bulanık Rogers ile bulanık IEC (International Electrotechnical Commission) oran ve klasik IEC ve Rogers oran yöntemleri kullanarak arızaların tespiti yapılmıştır. Bulanık yöntemlerin klasik yöntemlere göre daha iyi sonuç verdiği görülmüştür.

Use of phasor measurement units in power systems has emerged new real-time control techniques such as wide area damping control (WADC). WADC systems were shown to be very effective if the network induced time delay is handled properly. Delay compensation techniques based on constant delay assumption lack robustness and many of techniques assuming time variant delay are not suitable for real-time systems due to resulting complex structures of controllers or the strict requirements imposed on signal transmission. Handling time delay adaptively by switching among a set of lead controllers to provide required compensation based on online measurements shown to be both practical and robust. Here, frequent switching between the controllers should be avoided in order to avoid sustained oscillations. Putting a limit on switching period hinders proper delay compensation. This paper presents algorithms for adaptive selection of switching period based on the condition of network traffic in order to provide near real-time delay compensation. Network activity is observed by a metric defined as the difference of the average time delays measured in consecutive intervals. Based on this metric, switching period is decreased adaptively when time delay characteristics change fast. For slow changing dynamics of time delay, the algorithm picks longer switching periods in order to prevent sustained oscillations. Performance evaluation of the proposed algorithms are conducted by a WADC system designed for two-area, four-machine benchmark model. The algorithms are shown to be successful in tracking the fast changing dynamics of a communication network through simulations.