Yazarlar
- Ozden, Talat(16)
- Akinoglu, Bulent G.(15)
- Sezer, İsmet(11)
- Basoglu, Mustafa Engin(9)
- Özden, Talat(8)
- Akpinar, Adem(7)
- Terhan, Meryem(7)
- Başoğlu, Mustafa Engin(6)
- Cakmak, Recep(6)
- Erol, Ismail(6)
- Peker, Iskender(6)
- Turan, Rasit(6)
- Akpinar, A.(5)
- Ar, Ilker Murat(5)
- Kömürcü, Murat Ihsan(5)
- Sezer, Ismet(5)
- Altas, Ismail H.(4)
- Altuner, Elif Esra(4)
- Benli, Tolga(4)
- Bozbeyoglu, Pinar(4)
- Kaygusuz, K.(4)
- Tunç, Merve Tuğçe(4)
- Akyol, Mehmet(3)
- Altan, Aytaç(3)
- Barut, Abdulkadir(3)
- Bilgin, Atilla(3)
- Genc, Omer(3)
- Kankal, Murat(3)
- Kaygusuz, Abdullah(3)
- Kaygusuz, Kamil(3)
- Ozden, T.(3)
- Pilatin, Abdulmuttalip(3)
- Saribiyik, Oguz Yunus(3)
- Searcy, Cory(3)
- Timurkutluk, Bora(3)
- Toros, Serkan(3)
- Turan, İsmet(3)
- Yanarates, Cagfer(3)
- Yanarateş, Cağfer(3)
- Çakmak, Recep(3)
Yayınlar
- MakaleAçık Erişim2026Valorization of Moss biomass as a natural porous Matrix for shape-stable phase change material (PCM) composites
Can, Ahmet; Ganguly, Sauradipta; Gencel, Osman; Sarı, Ahmet; Erata, Hüseyin
Phase change materials (PCMs) are used to improve energy efficiency, particularly in building heat storage and passive thermal management applications. In this study, moss biomass ( Calliergonella cuspidata (Hedw.) Loeske) (Ca) was evaluated as a natural porous matrix, and a novel non leachable composite phase change material (PCM) was developed based on n-octadecane (n-OD). The moss biomass was impregnated with 60% n-OD by direct mixing method, and its structural stability was enhanced by the addition of Sodium silicate (SS) at 10% and 30% (by wt%) respectively. The morphological, chemical, and thermal properties of the composites were characterized by SEM, EDS, FTIR, DSC, TGA, XRD, and thermal conductivity analyses. SEM-EDS results showed that the moss biomass (Ca) had high porosity, with the addition of SS resulting in a more compact and homogeneous structure. FTIR analyses exhibited the formation of Si–O–Si bands, indicating successful integration of SS into the matrix. According to DSC analysis, the Ca/n-OD(60%) composite had a melting temperature of 26.1 °C and a melting enthalpy of 153.7 J/g whereas for the SS-added variants, these values were measured as 148.3 J/g (10%) and 144.2 J/g (30%), respectively. The enthalpy losses of only 2–3 J/g after 700 heating-cooling cycles indicated high thermal stability. TGA and XRD analyses showed that the addition of SS increased the thermal resistance of the composites, creating an amorphous network structure. The results indicate that moss-based Ca/n-OD/SS composites, with their compact, leak-free structure, high heat storage capacity, and excellent cyclic stability, hold promise as eco‑friendly materials for subsequent applications in: thermal energy storage for buildings, solar energy systems, and the thermal management of electronic components.
- MakaleÖn baskısı açık2026Mixed Method Investigation of the Major Challenges to the Sustainable Deployment of the Electric Vehicle Charging Station Network in Türkiye
Erol, Ismail; Oztel, Ahmet; Peker, Iskender; Ar, Ilker Murat; Benli, Tolga; Turan, İsmet
Charging the increasing number of electric vehicles (EVs) in use requires the deployment of EV charging station networks (EVCSN). However, there are various challenges to deploying EVCSN in a sustainable manner. Türkiye, a developing country, should also build a robust EVCSN to encourage future adoption of EVs as the country’s market for EVs has been rapidly growing. The literature review concludes that no previous study has systematically explored challenges to the sustainable deployment of EVCSN. The goal of this study is, therefore, twofold: first, it identifies those challenges through the lenses of commonly used theories. Second, it explores them using a multi-criteria decision-making (MCDM) framework that incorporates a rough-derived interval-valued neutrosophic set (R-IVN)-based ISM into MICMAC. By deriving interval neutrosophic information from single-valued expert inputs using rough number operators, the proposed approach more accurately captures epistemic uncertainty and variability in expert judgments compared to conventional interval-based models. The method is further validated through a novel Dice–Sørensen similarity index-based simulation approach. The findings of this study suggest that developing government policies and regulations and addressing the existence of vertically integrated companies are the critical challenges with higher driving powers. These findings provide key responsibilities for stakeholders, including urban municipalities, in developing guidelines for EVCSN deployment.
- MakaleYalnız künye20263-D magnetotelluric modeling and radiogenic heat reservoir for EGS development: A case study of the Kestanbol Granitoid intrusion (NW Türkiye)
Büyük, Ersin; Hacioglu, Ozlem; Ayzit, Tolga; Baba, Alper
Enhanced Geothermal Systems (EGS) provide firm, low-carbon baseload power and can contribute to reducing fossil-fuel-based energy generation. Granites and granitoids are particularly favourable EGS hosts due to their widespread occurrence, fracture-controlled permeability, and long-term heat supply from radiogenic decay. This study proposes an EGS development plan for the Kestanbol Granitoid Intrusion (KGI) in NW Anatolia, T & uuml;rkiye, based on a three-dimensional magnetotelluric (MT) model integrated with geochemical constraints on radiogenic heat production (RHP). We invert MT data acquired at fifty unevenly spaced sites to image the 3D resistivity structure of the KGI and its surroundings, resolving a highly resistive plutonic body bounded by relatively conductive fault-fracture zones. To quantify the radiogenic heat reservoir, we determine RHP rates from uranium, thorium, and potassium concentrations measured on twenty-seven rock samples from the KGI and adjacent lithologies, and integrate these values with the MT-derived pluton geometry. When combined with the regional stress regime, the integrated results indicate that the KGI hosts elevated RHP relative to surrounding rocks and that its internal structure and fault-controlled permeability architecture are favourable for EGS development. In particular, the north-western margin of the KGI emerges as the most promising target for injection-production well pairs. This workflow demonstrates how integrated MT, geochemical, and structural analyses can provide a quantitative, site-specific basis for EGS prospect ranking and drilling strategy in radiogenic granite/granitoid provinces. Overall, we propose a site-specific and risk-aware EGS development plan for the KGI that couples subsurface structure, radiogenic heat supply, and permeability architecture, providing a transferable framework for assessing radiogenic granite/granitoid provinces.
- MakaleAçık Erişim2025Yapay Zekâ Enerji Talebinde Çevresel-Fiskal Zaman Tutarsızlığı: Kurumsal Bir Yaklaşım
Çıçen, Yıldırım Beyazıt
Bu çalışma, yapay zekâ (YZ) temelli teknolojilerin hızla artan enerji talebinin çevresel ve mali etkilerini birlikte değerlendiren özgün bir teorik model geliştirmektedir. Model, YZ altyapısının ekonomik faydalarını, iç ve dış çevresel zararlarını ve kamu bütçesine yansıyan teşvik maliyetlerini tek bir refah fonksiyonu içinde birleştirerek “YZ kaynaklı çevresel–fiskal zaman tutarsızlığı” kavramını formelleştirmektedir. Bulgular, politikacının kısa dönemli YZ faydalarını abartması, enerji teşviklerinin maliyetleri maskelemesi ve uluslararası dışsallıkların sınırlı içselleştirilmesi nedeniyle politik denge enerji düzeyinin toplumsal optimumun üzerinde gerçekleştiğini göstermektedir. Kurumsal kalite arttıkça bu sapma azalmakla birlikte, yapısal parametreler nedeniyle tamamen ortadan kalkmamaktadır. Çalışma, enerji tüketiminin yalnızca teknik bir maliyet unsuru değil; maliye politikası, çevre regülasyonu ve uluslararası iklim iş birliği tarafından şekillenen çok katmanlı bir yönetişim problemi olduğunu ortaya koymaktadır. Son bölümde sürdürülebilir maliye politikaları ve yeşil finans açısından politika önerileri sunulmaktadır.
- MakaleAçık Erişim2025Sumak ekşisi üretiminde ohmik ısıtma destekli evaporasyonun kullanımı: Kalite parametreleri ve proses koşulları üzerindeki etkileri
Baltaci, Cemalettin; Odabaş, Halil İbrahim; Tunç, Merve Tuğçe
Bu çalışma ile ohmik ısıtma destekli evaporasyonun sumak şurubu üretimi üzerindeki etkilerinin incelenmesi amaçlanmıştır. Bu amaçla hem geleneksel evaporasyon hem de ohmik ısıtma destekli evaporasyon yöntemleri kullanılmıştır. Ohmik ısıtma destekli evaporasyon işleminde 20 V/cm (188 V) ve 25 V/cm (235 V) olmak üzere iki farklı voltaj gradyanı uygulanmıştır. Çalışmada, örneklerin fizikokimyasal parametreleri, HMF (5-hidroksimetilfurfural) miktarları, antioksidan özellikleri, reolojik karakteristikleri ve uygulanan metotların enerji tüketimi ile diğer proses parametreleri incelenmiştir. Ohmik ısıtma destekli ve geleneksel evaporasyon yöntemleriyle üretilen sumak şurupları arasında antioksidan özellikleri veya HMF miktarları açısından önemli bir farklılık bulunmamıştır. Ancak enerji verimliliği açısından incelendiğinde, ohmik ısıtma destekli evaporasyon işlemi sırasında enerji tüketiminin (20 ve 25 V/cm için sırasıyla 121,93±5,98 ve 95,00±3,08 kj), geleneksel yönteme göre (1331,00±101,82 kj) yaklaşık on bir kat daha düşük olduğu hesaplanmıştır. Elde edilen sonuçlar incelendiğinde, ohmik ısıtma destekli evaporasyon ile üretilen sumak ekşilerinin kalite özelliklerini korunurken, enerji tüketimini, CO₂ emisyonlarını ve proses parametrelerinin önemli ölçüde azaldığını göstermiştir.
- MakaleAçık Erişim2025Electricity in Ottoman Commercial Enterprises as a New Power Source
Damlibag, Fatih
Until the last quarter of 19th century, steam power was the only available source of power for commercial enterprises. But this power required large amounts of investment. This requirement limited the spread of mechanization. But the invention of electrical motors changed the situation. With its practical usage opportunities, electricity took attention of several commercial enterprises in the Ottoman Empire. According to former steam power, electricity provides both usage easiness and lesser cost opportunity to commercial enterprises. Thanks to electrical engines, relatively small businesses were also able to take decision of mechanization. In this article, there were shown examples from six sectors, who wanted to benefit from electricity in their activities. Entrepreneurs made investments in mining, logistics, jewelry, transportation, ginning and milling, for this new technology. With electricity investments, entrepreneurs wanted to reach seven advantages that there were communication possibility, safer working environment, energy efficiency, better lighting, easy utilization, reduced cost and increased productivity. As to the Ottoman government's approach to these entrepreneurs, the officials did not always eagerly meet their demands. Most of the custom officials were reluctant to accept electrical appliances into the country. But in the end, demands of entrepreneurs were mostly accepted by the government. For the control of these demands, the Ottoman Empire wanted both the purpose of each request and the person responsible for that request to be clearly determined.
- MakaleYalnız künye2025Performance assessment of solar-powered electric vehicles: Importance of maximum power point tracking, range enhancement and charging frequency analysis under various operating and irradiance conditions
Başoğlu, Mustafa Engin
Decarbonizing the transportation sector is becoming a crucial focus in the 21st century. As the popularity of internal combustion engine vehicles declines, the adoption of hybrid and electric vehicles (EVs) is significantly increasing. One of the main challenges for battery-powered vehicles, aside from safety concerns, is the limited driving range and frequent charging requirements. Integrating a photovoltaic (PV) module onto a vehicle's surface enables continuous battery charging during both motion and stationary periods, thereby extending the vehicle's range on a full charge. This study presents two main contributions: a modified 0.8VOC-based maximum power point tracking (MPPT) method for fast-changing irradiance conditions for flat-roof vehicle-integrated PV (VIPV) systems, and a long-term simulation analysis of classical MPPT methods using two new indicators for range extension and vehicle charging frequency variations under different irradiance profiles. The proposed MPPT method yielded superior energy performance, achieving 16–25 % higher energy generation compared to both the incremental conductance (IC) algorithm and the variable step-sized (VSS) perturb and observe (P&O) method. Long-term simulations conducted for three EV models demonstrated a daily driving range extension of 2–7 km with an 185W PV module, along with up to a 19 % reduction in charging frequency, depending on the battery capacity and vehicle models.
- MakaleAçık Erişim2025The impact of photovoltaic panels on the environment and yield parameters in an open field agrivoltaic system: A case study in Ayaş, Ankara
Senturk, Bilge; Oylek, Yelda; Kanar, Zeynep Sevim; Celik, Ridvan; Kurtulus, Gunes; Ozden, Talat
Agrivoltaic systems represent an innovative approach that integrates energy production and agriculture by installing elevated photovoltaic modules over farmland. In this study, the critical parameters on microclimate and microenvironment conditions — soil moisture and temperature, relative humidity, ambient temperature, photosynthetically active radiation, wind speed — and crop yield amount were monitored and analyzed in a single axis tracking AgriPV system installed in Ankara, Türkiye. Results indicate that under the 35 % coverage AgriPV system, photosynthetically active radiation decreased by 38.55 %. Additionally, soil moisture was found to be higher at 20 cm below under the AgriPV system compared to the reference field during the plant growth period. The yield data showed a considerable difference in crop amount under the AgriPV system across different harvest periods. The results are critically important for developing models in future phases that aim to predict and optimize the agricultural and ecosystem performance of AgriPV systems.
- MakaleAçık Erişim2025Motivating Green Transition: Analyzing Fuel Demands in Turkiye Amidst the Climate Crisis and Economic Impact
Coruh, Emine; Yıldız, Mehmet Selim; Urak, Faruk; Bilgic, Abdulbaki; Cengiz, Vedat
Decarbonizing the transportation sector is critical for sustainable development, particularly in rapidly urbanizing countries like Turkiye. This study analyzes fuel demand elasticities for diesel, gasoline, and LPG across 12 NUTS-1 regions of Turkiye in 2022, using a panel random effects SUR approach. The model accounts for regional variation and fuel interactions, producing robust estimates that uncover significant spatial and temporal differences in consumption patterns. Uniquely, diesel demand displays a significantly positive price elasticity, challenging the conventional assumption of inelasticity. Gasoline demand is moderately price-sensitive, while LPG appears relatively unresponsive. Strong cross-price elasticities—especially between diesel and gasoline—point to substitution effects that can inform more adaptive policy frameworks. Seasonal fluctuations and Istanbul’s outsized impact also shape national trends. These findings underscore the need for differentiated region- and fuel-specific strategies. While higher gasoline taxes may effectively reduce demand, lowering diesel and LPG use will require complementary measures such as infrastructure upgrades, behavioral incentives, and accelerated adoption of alternative fuels. The study advocates for regionally adjusted carbon pricing, removal of implicit subsidies, and targeted support for electric and hybrid vehicles. Aligning fiscal tools with actual demand behavior can enhance both the efficiency and equity of the transition to a low-carbon transportation system.
- Kitap BölümüAçık Erişim2025Ensuring Circularity through Outsourcing Decisions in Solar Photovoltaic Supply Chains
Erol, Ismail; Peker, Iskender; Benli, Tolga; Ar, Ilker Murat
Because solar photovoltaic (SPv) panels have seen such significant cost reductions in recent years, it has proven to be by far the most dynamic forms of renewable power generation. However, the transition from linear to circular is also crucial for building sustainability in SPv supply chains. The circular economy (CE) is appealing in part because of its ability to bring economic and environmental development objectives together to ensure sustainable production and consumption. To aid in the shift to a more circular economy, several circular-based strategies for various functions such as procurement can be developed. In this study, critical success factors (CSFs) to ensure circular outsourcing structure in SPv supply chains are identified and scrutinized. To achieve this, a multi-criteria-based methodology is proposed. The findings of this study argue that understanding the actual implications of not converting to circular outsourcing (C12) is the most significant cause CSF. This study also provides several implications.
- MakaleAçık Erişim2025The relationship between CO2 emissions, renewable energy and economic growth in the US: evidence from symmetric and asymmetric spectral granger causality analysis
Zuhal, Mustafa; Göcen, Serdar
This study analyzes the relationship between renewable energy consumption, CO2 emissions, and economic growth for 1973:M01-2022:M06 in the USA. The study employs Spectral Granger Causality analysis symmetrically and asymmetrically. The symmetric causality test presents a bidirectional causality relationship between CO2 emissions, renewable energy consumption, and economic growth. Regarding asymmetric causality results, there is bidirectional causality between positive and negative shocks of CO2 emissions, renewable energy consumption, and economic growth. The results suggest that renewable energy consumption is essential in increasing sustainable economic growth and environmental quality for the USA.
- MakaleAçık Erişim2025Hydrodynamic optimization of full-scale aeration tanks using field measurements and computational fluid dynamics modeling
Yılmaz Çelik, Damla; Yılmaz, Naz; Şibil, Rahim; Aras, Egemen; Vaheddoost, Babak
Improving energy efficiency and operational performance in wastewater treatment plants largely relies on precise hydrodynamic analysis. In this context, field-based studies are essential for understanding system behavior under real operational conditions. This study was conducted at a full-scale wastewater treatment plant, where flow dynamics in the aeration tank were evaluated through extensive field measurements and computational fluid dynamics modeling. Data were collected from 98 locations across 15 different depth levels using an Acoustic Doppler Current Profiler and a Hach FH950 velocity meter. The numerical model was initially validated with the help of experimental field data, enabling an accurate assessment of flow characteristics at varying depths. Results revealed that the low-velocity zones and non-uniform velocity distributions negatively affect system performance. It is also concluded that the inlet and outlet positions disturb the favorable circulation patterns and flow uniformity. Geometric optimization strategies were implemented to develop solutions, which led to a more uniform velocity distribution and improved hydraulic efficiency. By integrating detailed field measurements with numerical modeling, this study provides a comprehensive understanding of aeration tank hydrodynamics and offers practical design recommendations for improving overall system performance.
- MakaleAçık Erişim2025Future of Clean Cooking Energy Access in Emerging Economies by 2030
Cakir, Mehmet Ali; Unlu, Ramazan; Cakir, Sümeyra Cay; Xanthopoulos, Petros
This study assesses the future of clean energy and technology access for cooking in emerging economic blocs—BRICS, MINT, ASEAN, and MENA—through 2030. Cooking contributes 3% of global greenhouse gas emissions, with over half of household emissions coming from cooking. Therefore, clean cooking energy is critical for sustainability and human health. The study aims to evaluate the likelihood of achieving the UN Sustainable Development Goal of universal clean cooking energy access by 2030 and the 2050 net-zero emissions target. Machine learning techniques, such as support vector regression, gradient boosting, and linear regression, alongside an ensemble approach, provide forecasts for these regions. The findings show a varied outlook. Within ASEAN, two countries are expected to reach 100% clean energy access for cooking by 2030, while two are likely to experience a decline. The MENA region shows stronger progress, with eight countries expected to meet the 2030 target. Among BRICS countries, only India is projected to reach full accessibility, while Russia faces a decline. The MINT countries face challenges, with none expected to meet the target, and Nigeria is projected to experience a decrease in clean energy access. The study concludes that the current trajectory makes achieving the 2030 Sustainable Development Goals and the 2050 net-zero emissions target unlikely for these regions. Policymakers must reassess their strategies and learn from successful countries to improve outcomes.
- MakaleAçık Erişim2025FinTech driven green energy transition foreign direct investment and ecological footprint in BRICST countries
Ayaydin, Hasan; Ergün, Tolga; Barut, Abdulkadir; Erdem, Azad; Pilatin, Abdulmuttalip
The increasing emphasis on climate change and environmental sustainability worldwide has brought about the convergence and increased focus on financial technologies (FinTech) and green energy initiatives. In light of this, the study's objective is to investigate how FinTech moderates the relationship between the ecological footprint (EF) and green energy transition (GTE) in the BRICS-T nations between 1990 and 2021. This study examines how fintech moderated the GTE and EF in the BRICS-T from 1990 to 2021. We applied the Fully Modified Ordinary Least Squares (FMOLS) and used Dynamic Ordinary Least Squares (DOLS) as the main estimators for longitudinal analysis. In contrast, Driscoll-Kraay was used to verify the robustness of the results under cross-sectional dependence and heteroskedasticity. The results reveal that FinTech indirectly hinders EF by facilitating GTE. The outcomes also show that FinTech significantly constrains EF, while GDP and industrialization worsen EF. The results also confirm the important role of GTE and foreign direct investment (FDI) in reducing CO2 emissions in BRICS-T countries. Lastly, the paper offers policymakers useful recommendations for lowering EF in light of these outcomes. The study suggests establishing appropriate policies and strategies that encourage FinTech platforms to invest in green energy projects, including financial technology, promoting energy-efficient and low-carbon foreign direct investment, and encouraging GTE.
- Derleme MakaleAçık Erişim2024A review on effects of diethyl ether on cyclic variations in diesel engines
Sezer, İsmet
Diethyl ether (DEE) can be used in diesel engines as a fuel or fuel additive. The review study was compiled from the findings of several studies in this area. The diverse techniques are employed to mitigate the detrimental pollutants emitted by diesel engines. The first approach to reducing emissions involves altering the fuel system and engine design to improve combustion, but this is an expensive and time–consuming process. The utilization of various exhaust gas devices, such as a particle filter and catalytic converter, is necessary for the second way. However, the engine performance could be negatively impacted by these tools. Additionally, these exhaust devices increases the vehicle and maintain costs. The use of different alternative fuels or fuel additives is the third way that reduces emissions while improving engine performance. The particulate matter (PM), smoke, and nitrogen oxides (NOx) are the main environmental pollutants released by diesel engines into the atmosphere. The decreasing PM and NOx emissions at the same time is practically very difficult. The majority of researches indicate that using alternative fuels, such as natural gas, biogas, and biodiesel, or blending additives with conventional or alternative fuels, is the best way to reduce emissions. However, the characteristics of the fuel have a significant influence on cycle variations, which have a significant impact on engine performance, fuel economy, and emissions. Therefore, it is very important that the results of studies on the impact of DEE on cyclic variation are evaluated together to practice applications and to guide future studies. As a result, the primary focus of this study is on the usage of DEE as a fuel or fuel additive with different diesel engine fuels. The aim of this review is to investigate, using the available knowledge in literature, how DEE affects cyclic variations.
- MakaleAçık Erişim2024Thermal Power Plant Performance Analysis by Estimating Boiler Efficiency via Indirect Method: A Case Study
Celen, Pinar; Erdem, Hasan Hüseyin
In this paper, a coal (lignite) fired thermal power plant having capacity of 160 MW is taken into consideration and the impact of condenser pressure, moisture content of lignite, excess air coefficient, the efficiency of turbine pressure and heater numbers on power plant thermal efficiency is investigated. It is aimed to determine the performance losses of each equipment by means of thermodynamics and economic analysis. In this scope, it is expected that the power plant operator will be able to evaluate the reduction potential of equipment performance losses and ensure more effective use of the power plants by correctly planning the maintenance and rehabilitation needs and time. In the calculations, the boiler efficiency was determined with EN 12952-15 standard (indirect method) since this method has higher accuracy in coal-fired boilers. It is seen that the condenser pressure and excess air coefficient increments have no significant impact on power plant efficiency compared to moisture content of lignite, excess air coefficient, efficiency of turbine pressure and heater numbers. The significant effect is observed for fuel moisture content which rises from 22% to 47% and the power plant efficiency falls from 40% to 28%. The variation of the power plant thermal efficiency in case of failure of heaters is investigated and the power plant efficiency has decreased from 40.17% to 36.09% when the pre-heaters are no longer in to be in use because of any reason. In addition, revenue losses are estimated for each main equipment efficiency reduction for better use of power plant capacities and electricity lowering production costs.
- MakaleAçık Erişim2024Assessment of Greenhouse Gases Emissions from Dam Reservoirs: the Case of Tuzluca Dam
Akgün, Çağrı; Nas, Salim Serkan
It is a known fact that large dam projects built to serve important purposes such as electricity generation, irrigation drinking water supply, and flood control cause greenhouse gases emissions due to the areas they flood. In this study, the greenhouse gases emission impacts of the Tuzluca Dam and Hydroelectric Power Plant (HPP) project, planned to be constructed in the Iğdır province of Turkey, were evaluated. Analyses conducted using the G-res tool, developed by the United Nations Educational, Scientific and Cultural Organization (UNESCO) and the International Hydropower Association (IHA), estimated that the Tuzluca Dam and HPP project will emit 2,228 tCO2e of greenhouse gases annually once the dam begins to hold water. In accordance with the guidelines of the Intergovernmental Panel on Climate Change (IPCC), it is predicted that when emissions occurring before the dam and during its construction are included, the net greenhouse gases emissions of the project will be -902 gCO2e per square meter annually. The results obtained from this study were found to be consistent with similar studies in the literature.
- Derleme MakaleAçık Erişim2024Production of 5-Hydroxymethylfurfural from Non-edible Lignocellulosic Food Wastes
Muslu, Ayşe; Üçüncü, Osman; Baltacı, Cemalettin
The compound 5-(hydroxymethyl)furfural (HMF) has emerged as a versatile intermediate with the ability to undergo conversion into both fuel and a variety of platform chemicals. Lignocellulosic biomass, such as hazelnut shells and tea processing residues, was employed in this study for HMF production through two distinct methods. In the first method, cellulose from biomass was converted to sugars using a 4% acid solution, followed by catalytic conversion with NaCl/CrCl3.6H2O. After a 1-h reaction at 131 °C in a high-pressure system, HMF was obtained from tea processing waste and hazelnut shells with yields of 8.6% (82.3 mg/g) and 6.7% (66.7 mg/g), respectively. The second method involved LiCl/NaCl-doped N,N-dimethylacetamide (DMA) as an ionic solvent system for HMF production. After a 2-h reaction at 131 °C in the DMA-NaCl/[EMIM]Cl ionic solvent system, HMF was obtained from tea processing waste and hazelnut shell celluloses with yields of 5.7% (57.5 mg/g) and 3.1% (31.3 mg/g), respectively. This study contributes to the economic conversion of various food wastes into valuable chemicals, highlighting the potential of lignocellulosic biomass in sustainable chemical production.
- MakaleYalnız künye2024Caprock integrity at Çanakkale-Tuzla hydrothermal system inferred from magnetotelluric modeling using particle swarm optimization
Büyük, Ersin; Karaman, Abdullah
The impermeable caprock within a geothermal system serves the purpose of effectively sealing the reservoir, resulting in an elevation of both pressure and temperature. This sealing mechanism plays a crucial role in the long-term preservation of the system while also contributing to its overall sustainability. Caprock failure subsequent to seismic activity near a geothermal site can lead to the permeation of the caprock structure, resulting in diminished sealing capabilities and a decline in the reservoir temperature. In addition, this process alters the geochemical composition of the water by creating a hydrothermal mixture zone that disrupts the resistivity structure of the caprock, which is typically characterized by low resistivity values due to its substantial clay content and mineral alteration. This study focuses on investigating the integrity of the caprock at the Çanakkale-Tuzla geothermal field in Turkey, where water temperature and conductivity were reported to have decreased after a moderate-magnitude earthquake and subsequent aftershocks. For this purpose, we have performed magnetotelluric (MT) measurements, a method known for its sensitivity to geochemical reactions. These measurements are conducted along two parallel profiles that encompassed a total of 32 stations. The particle swarm optimization (PSO) technique is used to overcome the subtle difficulties associated with conventional inversion methods in modeling the MT data of complex formations. This is the first study that overcomes the difficulties emanating from the caprock failure by modeling MT data using PSO. Our modeling approach produces resistivity images that we interpreted as the signature of the failed caprock following the earthquake at the study site. Our results appear to confirm the documented geochemical changes, or hydrothermal mixture zone around the caprock structure.
- MakaleAçık Erişim2024Bioethanol Production from Mulberry Molasses Waste with Ohmic-Assisted Hydrodistillation
Tunç, Merve Tuğçe; Genç, Berna; Karataş, Şeyda Merve
In this study, the fermentation process of bioethanol production conditions were optimized by response surface methodology. Mulberry molasses production waste was used as the only carbon source for yeast fermentation to produce bioethanol. Hydrodistillation (HD) and ohmic-assisted hydrodistillation (OAHD) methods were employed to concentrate the bioethanol. Fermentation time (48–168 h), waste matter rate (5–45%) and pH (5–7) were selected as independent variables. Alcohol concentration was treated as the response. Optimum fermentation conditions were determined as 96.894 h fermentation time, 45% waste ratio and pH 7. At these optimum conditions, alcohol concentration was determined as 3.77 ± 0.33%. While the distillate obtained in the HD method contained 22.50 ± 1.89% alcohol, it showed 27.72 ± 0.24% in the OAHD method. The energy consumption values for OAHD and HD was 2.92 ± 0.51 and 53.24 ± 1.74 Wh/mL bioethanol, respectively. Results of study showed that the OAHD could be a cost-effective and green method to distillation of bioethanol from mulberry molasses waste.
