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Article Citation - WoS: 7Citation - Scopus: 8Solar Energy for the Airport Ground Support Equipment - a Quantitative Study(Emerald Group Publishing Ltd, 2023) Yildiz, Melih; Mutlu, Savas; Nagy, Andras; Kale, UtkuPurposeThis paper aims to evaluate the hypothetical situation in a resembling airport to Esenboga Airport and analyzes the condition of all ground support equipment (GSE) equipment to be supplied by electricity produced by solar panels mounted on the rooftop of the terminal building. The case is discussed using environmental emissions and economic feasibility. The results of the resembling case can be generalized to all airports for the reduction of emissions caused by ground operations of aviation. Design/methodology/approachGSE fleet data which has been prepared by TGS operated in the Esenboga Airport have been used to calculate emissions, and equivalent electricity consumption. A hypothetical solar panel construction on the rooftop of the terminal building and also the electricity production case was analyzed. Based on the calculations, both fuel and electricity use cases are compared by means of emissions and production costs using real data. FindingsThe electricity production and transmission pose a high value of emissions. Thus, electrification of GSE in the airport need a new approach such as producing the electric energy in the site. This research analyzes the case that the electricity is produced on the rooftop of terminal building and consumed by the GSE fleet. The authors discussed that it is both feasible and possible to electrify all the GSE except a shortage of two cold months with high fuel demand by using electric storage options. Practical implicationsGround handling is performed by using GSE which is historically powered by diesel and such internal combustion engines which are well known for their high emission rates. As most of the airports reside in populated areas, GSE emissions need to be evaluated for reduction. However the electric energy could be an alternative for GSE emissions reduction Originality/valueAviation is a system of many subsystems in which the performance of each unit plays a crucial role in the final success of the system. Concerns on environmental protection make the aviation industry focus on reducing emissions produced during operations. Although aircraft emissions are widely discussed in the literature, ground handling systems which are an integral part of the whole aviation system, also need to be studied regarding the environmental issues. Besides, the European Union has set out targets of reducing emissions at the airports during ground operations to zero. This paper discusses the possibility of the target by comparing various scenariosMaster Thesis Farklı Çalışma Koşulları Altında Güneş ve Rüzgar Sistemleri için Mppt Tekniklerinin Karşılaştırmalı Analizi(2023) Ahmad, Muhammad Saeed; Sünter, SedatYenilenebilir enerji teknolojileri, fosil yakıtlara güvenin azalması, iklim değişimlerinin etkisini azaltması gibi sebeplerden dolayı son birkaç 10 yıldır önem kazanmıştır. Güneş, rüzgar ve su gibi yenilenebilir kaynaklar temiz ve sürdürülebilirdir. Bu teknolojiler son yıllarda önemli derecede dikkatleri üzerine çekmiştir. Yenilenebilir enerji teknolojileri birçok avantajlara sahip olmalarına rağmen fosil yakıtlarına göre oldukça düşük verimlere sahip olmaları önemli bir dezavantajdır. Sonuç olarak, yenilenebilir enerji sistemleri, fosil-yakıt temelli sistemlerin ürettiği miktardaki bir enerjiyi üretmek için daha fazla yere ve kaynağa ihtiyaç duyarlar. İlave olarak, yenilenebilir enerji sistemlerinin verimi hava ve diğer çevresel koşullara bağlı olarak değişebilir. Örnek olarak, güneş panelleri bulutlu günlerde daha az etkiliyken rüzgar türbinleri de sakin (rüzgarsız) havada daha az etkilidir. Bu durumlar yenilenebilir enerji sistemlerinin üreteceği enerji miktarını tahmin ve kontrol etmeyi zorlaştırabilir. Bu durum yenilenebilir enerji sistemlerinin şebekeye entegrasyonunu zorlaştırabilecektir. Maksimum güç noktası takip (MPPT) tekniklerinin kullanılmasıyla verimle ilgili problemlerin üstesinden gelinebilir. Bu teknikler, maksimum güç noktasında veya en çok gücü üreteceği noktada çalışmayı sağlayarak yenilenebilir enerji sistemlerinin performansını optimize etmek için kullanılır. Birkaç çeşit maksimum güç noktası izleme (MPPT) tekniği vardır, fakat genel olarak üç kategoride sınıflandırılırlar. : Basit, Yapay zeka (AI) ve hibrit. PO ve IC gibi basit MPPT teknikleri en temel olanlardır ve MPPT'de oldukça fazla kullanılır. Bu teknikler, maksimum güç noktasını sağlamada sistemin çalışma koşullarını sürekli olarak ayarlamak için oldukça basit algoritmalar kullanırlar. PSO ve ANN gibi AI-temelli MPPT teknikleri, yenilenebilir enerji sistemlerinin performansını optimize etmek için ileri algoritmalar ve makine öğrenme teknikleri kullanır. Bu teknikler çevresel koşulların değişimine kendilerini uyarlayabilir ve gerçek zamanda sistemin çalışma koşullarını sürekli olarak ayarlayabilirler. ANFIS ve PSO&PO gibi hibrit MPPT teknikleri, basit ve AI-temelli tekniklerinin bir birleşimidir. Bu teknikler maksimum güç noktasını hızlıca takip etmek için basit algoritmalar kullanır ve daha sonra gerçek zamanda sistemin çalışma koşullarının ince ayarı için AI-temelli teknikler kullanırlar. Hibrit enerji (güneş ve rüzgar) sistemleri için basit, AI, ML ve hibrit MPPT tekniklerinin karşılaştırmalı analizi bu tezde sunulmuştur. MPPT algoritmaları, verim, yerleşme zamanı, MPPT noktasında salınım ve algoritma karmaşıklığı gibi farklı metriklere dayanan verilere göre sıralanmıştır. PV sistem için, hibrit ve konvansiyonel tekniklere göre AI-temelli teknikler en iyi performansı göstermiştir. Rüzgar sistemi için ise, konvansiyonel ve AI tekniklerinin faydalarını birleştiren hibrit teknikler en iyi sonucu göstermiştir.Article Driving Electric Field Effects on the Space Charge Limited Photocurrent of In6s7<(Natl inst Optoelectronics, 2013) Qasrawi, A. F.; Al-Balshi, Madleen A.; Gasanly, N. M.; Department of Electrical & Electronics EngineeringA new type of photovoltaic materials, which are designed on the base of In6S7 single crystals using silver and gold metals to construct Ag/In6S7/Au point contacted photocells, are reported and discussed. The influence of the driving electric field on the performance of the device was tested. The current density-electric field dependence curve reflected a space charge limited photocurrent effect being dominant in the field region of 1.0-4.3 V/cm. In addition, the In6S7 photocell short circuit and loaded current dependencies on the excitation intensity were measured. The short circuit current was observed to exhibit exponential trap distribution effect and supralinear recombination at low and high illumination intensities, respectively. The device displays a current density of 0.5 mA/cm(2) for excitation intensity of 76 klux. When loaded, it displayed a stable power dissipation curve. Such behavior reflects the novelty of these types of cells for future application.Conference Object Citation - WoS: 65Citation - Scopus: 77Modelling and Simulation of a Hybrid Solar Heating System for Greenhouse Applications Using Matlab/Simulink(Pergamon-elsevier Science Ltd, 2013) Kiyan, Metin; Bingol, Ekin; Melikoglu, Mehmet; Albostan, AyhanSolar energy is a major renewable energy source and hybrid solar systems are gaining increased academic and industrial attention due to the unique advantages they offer. In this paper, a mathematical model has been developed to investigate the thermal behavior of a greenhouse heated by a hybrid solar collector system. This hybrid system contains an evacuated tube solar heat collector unit, an auxiliary fossil fuel heating unit, a hot water storage unit, control and piping units. A Matlab/Simulink based model and software has been developed to predict the storage water temperature, greenhouse indoor temperature and the amount of auxiliary fuel, as a function of various design parameters of the greenhouse such as location, dimensions, and meteorological data of the region. As a case study, a greenhouse located in Sanhurfa/Turkey has been simulated based on recent meteorological data and aforementioned hybrid system. The results of simulations performed on an annual basis indicate that revising the existing fossil fuel system with the proposed hybrid system, is economically feasible for most cases, however it requires a slightly longer payback period than expected. On the other hand, by reducing the greenhouse gas emissions significantly, it has a considerable positive environmental impact. The developed dynamic simulation method can be further used for designing heating systems for various solar greenhouses and optimizing the solar collector and thermal storage sizes. (C) 2013 Elsevier Ltd. All rights reserved.Article Citation - WoS: 9Citation - Scopus: 11Real Options Valuation of Photovoltaic Investments: a Case From Turkey(Pergamon-elsevier Science Ltd, 2024) Or, Bartu; Bilgin, Gozde; Akcay, Emre Caner; Dikmen, Irem; Birgonul, M. TalatInvestments in renewable energy resources have become inevitable due to increasing energy demand and energy prices, diminishing non-renewable energy resources, and the outgrowth of carbon footprints. Photovoltaic (PV) systems offer high solar energy potential in sustainable energy production whereas their high initial costs necessitate critical strategic valuation of investments. Valuation with conventional methods has been challenging due to existence of uncertainties such as fluctuating PV panel prices, changing meteorological conditions with certain effects on power generation, and governmental policies on energy market regulations. This study aims to propose a real options approach to valuation of residential rooftop PV system investments considering these uncertainties and demonstrate benefits of this approach with an application on the residential PV investment decisions in Turkey. The proposed method, Real Options Valuation (ROV) with Least-Squares Monte Carlo Simulation (LSMC) considers the deferral option of the investor by utilizing stochastic simulations, the discounted cash flow method, linear regression, and backward dynamic programming and thus evaluates the effects of uncertainties on financial attractiveness of residential PV investments. The case study findings proved that ROV with LSMC having a 7-years deferral option supported the investment decision with realizable cost-effective options while "NPV method" resulted in an infeasible investment. Scenario analysis was also conducted to explore policy options that can be used to promote solar energy investments in Turkey. This study has a potential to have practical contributions for investors as well as implications for policy-makers.
