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Review Citation - WoS: 39Citation - Scopus: 42Hydropower in Turkey: Analysis in the View of Vision 2023(Pergamon-elsevier Science Ltd, 2013) Melikoglu, MehmetTurkey is a recently developed country, a regional power in the Middle East and an economic powerhouse of the region. Turkey's electricity demand is continuously increasing due to fast economic growth coupled with the country's vibrant young population. It is envisaged that this demand would keep on increasing almost exponentially in the next decade according to the recently avowed Vision 2023 agenda. According to which, the Turkish government ambitiously wants to provide 30.0% of the country's electricity demand from renewable energy sources by 2023. Turkey has vast renewable energy potential including hydro, geothermal, solar and wind. However, historically there is only one playmaker that is hydropower. Thus a detailed review of the current status and future prospects of Turkish hydropower market is urgently needed to generate a roadmap for the Vision 2023 agenda. This paper was intended to provide that vital information. Currently, more than 25.0% or 57.5 TWh of the country's electricity demand is supplied from hydropower. According to official projections this would increase to approximately 116.0 TWh in 2023. In this study, hydropower's supply rate of Turkey's annual electricity demand was assessed based on the official projections and a forecast was generated. Results showed that between 22.0% and 27.0% of Turkey's annual electricity demand should be supplied from hydropower in 2023. Therefore, between 22.5 TWh and 45.0 TWh of electricity should be generated from renewable energy sources other than hydropower to provide a total of 30.0% renewable energy based electricity generation in 2023. (C) 2013 Elsevier Ltd. All rights reserved.Article Citation - WoS: 64Vision 2023: Feasibility Analysis of Turkey's Renewable Energy Projection(Pergamon-elsevier Science Ltd, 2013) Melikoglu, MehmetElectricity consumption of Turkey at the year 2023 is estimated to be around 530,000 GWh. Turkey plans to supply 30% or 160,000 GWh of this demand from renewable energy sources according to the recently avowed government agenda Vision 2023. However, the current installed renewable energy capacity is around 60,000 GWh. Detailed literature analysis showed that only wind and solar energy potential in Turkey can solely supply this demand. In this study, two different scenarios were generated to analyse the cost and environmental impacts of supplying this demand. Scenario 1, which is derived from the official Vision 2023 targets, suggests supplying this demand from wind, solar, geothermal energy and hydropower. The total projected cost based on Scenario 1 is estimated to be $31.000 billion and annual greenhouse gas emissions of 1.05 million tonnes of CO2 equivalent. According to Scenario 2 or the contrary setup it is assumed that the required demand gap could not be supplied from new renewable energy investments but equally from coal and natural gas. The projected cost is estimated to be around $8.000 billion and annual greenhouse gas emissions at appalling 71.30 million tonnes of CO2 equivalent. Assuming carbon tax at the year 2023 to be $50 per tonne of CO2 emitted, supplying the demand from renewable energy sources according to Scenario 1 would generate savings worth nearly $2.175 billion from environmental taxes annually. Thus, making the payback time of the renewable energy investments less than 15 years. (C) 2012 Elsevier Ltd. All rights reserved.Master 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 Citation - WoS: 7Citation - Scopus: 9Reliability-Based Evaluation of Hybrid Wind-Solar Energy System(Sage Publications Ltd, 2021) Devrim, Yilser; Eryilmaz, SerkanIn this article, a hybrid system that consists of a specified number of wind turbines and solar modules is considered. In particular, the system is modeled using weightedk-out-of-nsystem which is also known as a threshold system in reliability literature. The system under concern consists ofn1identical wind turbines andn2identical solar modules, and each turbine and module can be in one of two states as working or failed. The probability that the entire hybrid system withn=n1+n2components produces power at minimum levelkis computed and evaluated. The importance of single-wind turbine and solar module is also calculated to measure which renewable energy component is more critical and important. Extensive numerical results that are based on real data set are presented to illustrate the model.Article Citation - WoS: 62Citation - Scopus: 78Hybrid Microgrid for Microfinance Institutions in Rural Areas - a Field Demonstration in West Africa(Elsevier, 2019) Ayodele, Esan; Misra, Sanjay; Damasevicius, Robertas; Maskeliunas, RytisWe present a hybrid energy microgrid optimization model for a microbank in a remote rural residential area. The model is based on the use of renewable (wind turbines & solar photovoltaic (PV)) and conventional (gasoline generators) energy sources and battery storage systems. We conducted a detailed assessment of a typical microbank's load, residential loads and energy resources in a village called Ajasse-Ipo in Kwara State, Nigeria. We performed the modeling of a hybrid microgrid system, followed by an economic analysis and sensitivity analysis to optimize the hybrid system design. We performed simulations based on the energy resources available (solar PV, wind, gasoline generator & battery energy storage system) to satisfy the energy demands of the microbank, while the excess energy was supplied to meet the demand of the community loads, i.e. water pumping machine and rural home lighting. The results obtained showed that the hybrid system comprising the solar PV/battery/diesel was most techno-economically viable with a Net Present Cost (NPC) and Cost of Energy (COE) of $468,914 and 0.667$/kWh, respectively. Comparing these results with those obtained using analytical methods, the solar PV, battery and converter sizes obtained were slightly higher than the optimal system configurations as produced by HOMER. The proposed hybrid energy system also allowed to achieve almost 50% reductions in CO2, CO, unburned hydrocarbons, particulate matter, SO2 & NO2. The system can be applicable for other rural regions in the developing countries with similar environmental conditions.Conference Object Design and Optimization of Green Hydrogen-Based Hybrid Energy System(International Association for Hydrogen Energy, IAHE, 2022) Ceylan,C.; Devrim,Y.Hydrogen (H2) is widely used in many industries because it can be used as a chemical raw material with its high mass-energy density and can be converted back into electricity via fuel cells. H2 energy systems seem to be one of the most effective solutions for providing a better environment and sustainability. Green H2, produced by renewable energy-assisted electrolysis without greenhouse gas emissions, has been of great importance in recent years. In this study, a hybrid energy system including Photovoltaic (PV), Wind Turbine (WT), Proton Exchange Membrane Fuel Cell (PEMFC), and electrolyzer is compared for grid-connected and off-grid operating conditions. In the grid-connected system, electricity generated from PV and WT is used directly to meet electricity demand, while excess electricity is used for green H2 production. In the off-grid connected system, electricity generated from PV and WT was used for H2 production. Produced H2 and O2 were used to generate electricity by PEMFC. While 20186 kWh energy & 3273 m3 H2 were generated in an on-grid connected system, 95145 kWh energy & 17942 m3 H2 and 83511 kWh energy & 14370 m3 H2 were generated in two different configurations in the off-grid connected system. The Levelized Cost of Energy (LCOE) for the on-grid connected system and the off-grid system for two different designs were determined as 0.307 $/kWh, 0.341 $/kWh and 0.349 $/kWh, respectively. The hybrid system design was simulated using MATLAB software and it was examined which hybrid energy system configuration would be the most economical to meet the load. © 2022 Proceedings of WHEC 2022 - 23rd World Hydrogen Energy Conference: Bridging Continents by H2. All rights reserved.Article Citation - WoS: 10Citation - Scopus: 11Is There Convergence in Renewable Energy Deployment? Evidence From a New Panel Unit Root Test With Smooth and Sharp Structural Breaks(Pergamon-elsevier Science Ltd, 2023) Corakci, Aysegul; Omay, TolgaThis study examines whether the contribution of renewable energy to the total primary energy supply converges in a panel of 24 OECD countries over the period 1960-2020. To this end, a new panel unit root test that allows for both sharp and smooth breaks is proposed to test for the stochastic convergence hypothesis. Although renewable energy convergence is not rejected when the newly proposed test is applied to the full panel of OECD countries, it found only moderate support within the members of the panel using a sequential panel selection methodology. In fact, in two high-income OECD countries, the contribution of renewable energy to the primary energy supply shows no sign of convergence: Poland and Iceland. Therefore, the renewable energy shares seem to be converging to a common steady state in only a group of OECD countries over the long run. This uneven pattern of convergence, in turn, suggests that the OECD countries are still far away from developing a common sustainable renewable energy target, calling for urgent international policy cooperation to encourage the divergent econo-mies to seek out the menu of policies that ensure the worldwide success of renewable energy transformation.Master Thesis Ters Elektrodiyaliz Sistemi için Poliepiklorohidrin Bazlı Anyon Değişim Membranları(2021) Karakoç, Ezgi; Güler, EnverTuzluluk gradyan gücü yenilenebilir, sürdürülebilir ve karbon içermeyen bir enerji kaynağıdır. Ters elektrodiyaliz sistemi, tuzluluk gradyan gücünden yararlanarak deniz ve nehir suyunun karışımı ile enerji üretiminde en etkili yöntemlerden biridir. Bu yüzden, bu teknoloji ile tuzluluk gradyan gücünden elektrik üretimi için ucuz ve uygun iyon değişim membranlarının geliştirilmesi önemlidir. Özellikle, anyon değişim membranlarının hazırlanması daha karmaşıktır ve bu nedenle istenen fizikokimyasal özelliklere ulaşmak için daha fazla çaba gerektirir. Bundan dolayı bu çalışmanın temel amaçları anyon değişim membranlarını üretmek, karakterize etmek ve onları laboratuvar ölçekli RED sisteminde test etmektir. Bu tezde aktif polimeri poliepiklorohidrin olan homojen anyon değişim membranları çözücü uçurma yöntemi ile laboratuvar ölçekli olarak üretilmiştir. Anyon değişim membranlarını üretirken farklı klor miktarlarına sahip (H, 37% klor ve C, 25% klor) iki tür poliepiklorohidrin kullanılmıştır. Membranların karışım oranları (aktif polimerin inert polimere kütlece oranı) 0.6 dan 2.0 a kadar, diamine oranları (çapraz bağlayıcının klorometil gruplarına kütlece oranı) ise 1.2 den 4.0 a kadar ayarlanmıştır. Bu anyon değişim membranlarını karakterize etmek için SEM, FTIR ve DSC analizleri incelenmiştir. RED sistemi için uygun membranı karşılaştırmak ve bulmak için iyon değişim kapasitesi, şişme derecesi ve sabit yük yoğunluğu belirlenmiştir. Karakterizasyon sonuçlarına göre bu membranlar RED sisteminde test edilmiş ve üç çift membran kullanılmıştır. Besleme akış hızları dakikada 30 ml, 60 ml, 90 ml ve 120 ml ve tuzluluk oranı 1:30 (g/g) olarak ayarlandı. En yüksek maksimum güç yoğunluk değeri 0.6 karışım ve 2.0 diamine oranında PECH-C esaslı anyon değişimli membranlar için 0,316 W/m2 olarak bulunmuştur. Bu çalışma, ters elektrodiyaliz sistemi ile enerji üretimi için PECH bazlı membranların tasarım ve optimizasyon potansiyelini kanıtlamaktadır. Anahtar Kelimeler: Tuzluluk gradyan gücü, ters elektrodiyaliz, poliepiklorohidrin, anyon değişim membranlarıArticle 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 scenariosArticle Citation - WoS: 11Citation - Scopus: 18Prospects of Ocean-Based Renewable Energy for West Africa's Sustainable Energy Future(Emerald Group Publishing Ltd, 2021) Adesanya, Ayokunle; Misra, Sanjay; Maskeliunas, Rytis; Damasevicius, RobertasPurpose The limited supply of fossil fuels, constant rise in the demand of energy and the importance of reducing greenhouse emissions have brought the adoption of renewable energy sources for generation of electrical power. One of these sources that has the potential to supply the world's energy needs is the ocean. Currently, ocean in West African region is mostly utilized for the extraction of oil and gas from the continental shelf. However, this resource is depleting, and the adaptation of ocean energy could be of major importance. The purpose of this paper is to discuss the possibilities of ocean-based renewable energy (OBRE) and analyze the economic impact of adapting an ocean energy using a thermal gradient (OTEC) approach for energy generation. Design/methodology/approach The analysis is conducted from the perspective of cost, energy security and environmental protection. Findings This study shows that adapting ocean energy in the West Africa region can significantly produce the energy needed to match the rising energy demands for sustainable development of Nigeria. Although the transition toward using OBRE will incur high capital cost at the initial stage, eventually, it will lead to a cost-effective generation, transmission, environmental improvement and stable energy supply to match demand when compared with the conventional mode of generation in West Africa. Originality/value The study will contribute toward analysis of the opportunities for adopting renewable energy sources and increasing energy sustainability for the West Africa coast regions.
