Countries prioritize secure and cheap energy over clean energy in their energy policies, and Türkiye is no different. The Strategy Plan 2015–2019 of the Ministry of Energy and Natural Resources emphasizes the exploitation of domestic coal for energy security, while Türkiye intends to curb its emissions by 41% by 2030. These two targets contradict in terms of climate change mitigation. In retrospect, this study aims to determine the role of coal, wind, and solar power in energy policy-making through scenario analyses. The results indicate that if Türkiye continued its pre-2020 energy policy, its use of domestic coal would be important for energy security. On the other hand, both wind and solar have the capacity to contribute to the country’s efforts towards energy security and climate change mitigation.

This study investigates the potential of chemically strengthened soda-lime-silicate (SLS) glass to mitigate Potential Induced Degradation (PID-s) caused by the shunting mechanism in photovoltaic (PV) modules, a key factor in efficiency losses in these systems. PID-s primarily results from the migration of sodium ions (Na+) from the SLS glass into the cell junctions, leading to reduced performance. In this study, we modified commercial SLS glass through an ion exchange process, substituting Na+ ions with potassium (K+) ions, which have a larger ionic radius, to improve resistance to PID-s. The modified glass was tested in a PIDcon Bifacial Device under accelerated test conditions, and the results were compared with untreated SLS glass. The findings showed that chemically strengthened SLS glass with K+ content significantly reduced Na+ migration compared to standard SLS glass. Given that cover glasses are the primary structural elements in PV modules, we also examined the mechanical properties and demonstrated that the ion exchange process improved the strength of the SLS glass by introducing a surface compressive stress state. Our results suggest that SLS glass, commonly used in the PV module industry, is a cost-effective solution for reducing PID-s degradation, and integrating this feature into modules does not necessitate the use of more expensive glass compositions, such as aluminosilicates, which are typically used for ion exchange treatments.

Outdoor tests of photovoltaics module are crucial both for marketing and for research and technological developments. The electric generation performance and their degradation rates and lifetime are also related to different climatic conditions of the regions. In this work, the outdoor tests are carried out for six different photovoltaic (PV) modules under Arid-steppe Climate condition of Ankara, Türkiye. Their degradation rates are calculated by using linear regression (LR) and year on year (YOY) methods. The comparison between LR and YOY are carried out and with the other performed studies of different regions of world. In addition, it is investigated that how effective the climatic conditions on daily degradation rates. The results obtained are as follows: Mono-Si and Hetero-junction Silicon (HIT) cell modules degradation rates of 0.71/1.56 %/year and 0.84 %/year are respectively obtained by LR method and 0.57/0.90 %/year and 0.85%/year are respectively by YOY method. The degradation rates for Cupper Indium Selenide (CIS), Cupper Indium Gallium Selenide (CIGS) and microcrystalline Silicon/Amorphous Silicon (µc-Si/a-Si) modules have 1.73/1.49 %/year, 11.55/9.52 %/year and 1.48 %/year for LR method and 1.28/1.12 %/year, 9.94/9.53 %/year and 0.99 %/year for YOY method are obtained respectively. It is also obtained for the Polycrystalline Silicon Modules as 1.20/1.86 %/year degradation rates by LR method and 0.79/1.88 %/year degradation rates by YOY method.

Concentrator photovoltaics (CPVs) have demonstrated high electrical efficiencies and technological potential, especially when deployed in CPV–thermal (CPV-T) hybrid absorbers, in which the cells’ waste heat can be used to power industrial processes. However, the high cost of tracking systems and the predominant use of expensive multi-junction PV cells have caused the market of solar co-generation technologies to stall. This paper describes the development and testing of a low-cost alternative CPV cell based on crystalline silicone (c-Si) for use in a novel injection-molded parabolic hybrid solar collector, generating both, photovoltaic electricity and thermal power. The study covers two different c-Si cell technologies, namely, passive emitter rear contact (PERC) and aluminum back surface field (Al-BSF). Simulation design and manufacturing are described with special attention to fingerprinting in order to achieve high current carrying capacities for concentrated sunlight. It was determined that Al-BSF cells offer higher efficiencies than PERC for the considered use case. Solar simulator tests showed that the highly doped 4 cm2 cells (50 ohm/sq) reach efficiencies of 16.9% under 1 sun and 13.1% under 60 suns at 25 °C with a temperature coefficient of −0.069%(Abs)/K. Finally, options to further improve the cells are discussed and an outlook is given for deployment in a field-testing prototype.

Energy security and climate change are among the top priority challenges for Turkey. High dependency on imported resources jeopardizes the economy, especially with high currency rate and conflicts in neighboring countries from where Turkey imports its energy. Besides, Turkey has already started to experience the impacts of climate change such as increasing temperature along with drought. Floating photovoltaics have proven themselves to be quite efficient in energy production, with evaporation reduction as a positive externality. The purpose of this article is to reveal the possible capacity of floating photovoltaics on constructed water reservoirs of Turkey and draw policy perspectives against existing or anticipated challenges. A total of 4,003 reservoirs were analyzed based on different water surface coverage scenarios. The results of the study proposed 125 TWh electricity generation, slightly above 40% of the nation-wide electricity demand, when 10% of suitable reservoirs were covered. This generation would be highly instrumental in reducing energy dependency and substituting renewables for conventional resource uses. Avoided CO2, thanks to this substitution, was calculated to be 77.1 Mton equivalent. This would obviously be favorable in light of the carbon emission reduction policy of the country and Paris Agreement requirements. Moreover, 1,242.1 hm3 freshwater was assessed to save resources from evaporation loss, which would help to mitigate the climate change pressure on water resources.

This study examines the macroeconomic carbon rebound effect for the European Union (EU) Emissions Trading System (ETS) by using data for the 2005–2019 period for 26 European countries. We estimate the panel data models which link emissions to allowances by controlling for economic growth, investment, employment, and energy intensity. The results from both the recent panel estimation approaches and Granger causality analysis indicate a macroeconomic carbon rebound effect of the EU ETS. The bidirectional Granger causality between emissions and allowances highlights a self-enforcing macroeconomic rebound. Energy intensity significantly impacts emissions directly and indirectly via the macroeconomic rebound effect. Our results show that positive economic spillovers of ETSs may hamper the efforts to meet climate targets.

Solar energy has an important role for increasing renewable energy use and circularity options in the sector are increasing. This study analyses the advances in the scope of the Sustainable Development Goals that aim to create a more equitable and peaceful world and a more livable environment. Studies that are focused on life cycle perspectives, opportunities for end-of-life management, and multiple goals, including climate action as well as responsible consumption and production are compared. This is used to understand synergies between the circular economy and solar photovoltaic technologies in Türkiye. A need analysis survey is conducted with the participation of academic institutions and research centers, producers, and other stakeholders who operate in the solar photovoltaic sector in Türkiye. The results are analyzed across stakeholder categories and used to derive policy recommendations based on the top drivers, barriers, and enablers to increase circularity in the sector. The expected impacts on environmental, economic and social aspects are also questioned to obtain perspectives on possible pathways. For the first time, the realization of sustainable solar photovoltaic waste management in the context of the circular economy is discussed by stakeholders in Türkiye to establish consensus, increase collaboration, and support planning of future opportunities.

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.

Mainstream energy policy emphasizes the exploitation of domestic sources to secure energy. Since readily available, many nations focus on fossil fuels, so they lack investment in the alternatives. The result is increasing atmospheric partial pressure of carbon dioxide, and energy security is still an issue. This study analyzes the impact of different variables on securing energy and reducing carbon emissions and attains this aim by econometrics. Energy-related data for 47 countries have been compiled from the IEA webpage, WDI, and BP databases, covering the period between 1990 and 2017. The results indicate that electricity generation by solar and wind globally helps both securing energy and climate change mitigation as anticipated. The dataset confirms that coal- and gas-based power generation does not contribute to global energy security. The dataset does not cast any distinct role on energy efficiency in terms of energy intensity. Increasing energy intensity, i.e., decreasing energy efficiency releases more carbon as anticipated. However, increasing energy intensity, i.e., decreasing energy efficiency, contributes to the energy security of the countries with wind power in the energy mix. One interesting result is that having a large population promotes energy security, but increasing urban population brings risks.

Turkey, which has immense solar potential, has recently shifted towards solar energy and new renewable energy deployment regulations, including implementation and commercializing rooftop PV technologies. Thus, these require a detailed assessment to determine the power source's capability and convince the policymakers. To the authors' best knowledge, there is no available data or a city-based study for the rooftop PV potential in Turkey. Here, we present the first city-based rooftop PV potential study in Ankara. The technical PV potential calculations are sensitive to the suitable area ratio, module efficiency, and module area assumptions. This study proposes a new, free, reliable, and open-source model for estimating the rooftop PV potential, and it is adaptable to every roof type. The suitable roof area for PV panels is calculated using Helioscope software. Five different modules with different efficiencies and module sizes are modelled in Helioscope. The results showed that Ankara's total technical PV potentials for residential, public, and commercial buildings are 1.15 TWh/year, 55 GWh/year, and 26.8 GWh/year, respectively. Best results are obtained by Mono-Si Halfcut (M-2) and Thin Film (M-5) modules in residentials, M-2 and Mono-Si Bifacial Modules (M-3) in Public and Commercial Buildings. (c) 2021 Published by Elsevier Ltd.

Photovoltaic Power Plants have a considerable share among solar energy conversion technologies toward environmentally sustainable and economically feasible electricity production. However, when a rural region's land surface formed by natural soil types is covered by a Photovoltaic Power Plant (PVPP)'s dark-colored solar modules in large numbers, an artificial albedo (reflectivity) change is expected on that surface. Because of the heat exchange between these modules and the air surrounding them due to albedo alteration, the region's natural weather conditions may experience Photovoltaic Heat Island Effect (PVHIE) as a result of external and time-dependent air temperature oscillations caused by the warming-cooling cycles of solar modules. To observe and analyze a possible PVHIE trend, it has been conducting a field study project since October 2017 for a PVPP near the Sekbandemirli rural region in the Kutahya city of Turkey. The weather data, including air temperature and wind (direction and speed) at every 10-minute and hourly intervals, are collected by the three weather monitoring stations installed at the specific locations inside and outside the PVPP field. The plant's hourly average power output and module temperature data can also be monitored. After conducting statistical, correlational, and graphical analyses, the results show some temporal PVHI formations at the PVPP field center daily and on a seasonal basis. The plant center's air temperature tends to be warmer (up to the 6°C difference) during daytimes and colder (up to the (-3)°C difference) during nighttimes.

Solar cells have over 50-years of development history; many different devices and technologies are studied over this time span, and interestingly it is still a hot research topic. Although the physical mechanisms involved in photovoltaic processes are rather fundamental, the characterization and classification of the research pathways seem complicated and can even lead to misleading argumentation. Various photovoltaic devices are classified as first, second- and third- generation based on the developments for the last 25 years to highlight the development history of diverse photovoltaic technologies. This classification may not be appropriate if the recent developments are considered. Wafer based solar cells are regarded as the first-generation and the thin-film solar cells as the second-generation. In the third-generation solar cells, there are many different applications that might be confusing if a firm classification would not be outlined. In the present article, we comprehensively classified the recent developments on the subject and presented an overall perspective. A brief review of the physics and physical mechanisms are given, and based on these mechanisms, a clear classification is outlined. Then, recent experimental and theoretical researches are presented together with a summary of the related review articles recently appeared in the literature.

Fresnel lenses are known and used for many years; yet the commercialization, especially in photovoltaic application is not well researched and analyzed. On the other side, although the photovoltaic power plants are rapidly entering the market, the major drawback is still the price of Si cells. In this work, we constructed a Fresnel lens of mini concentrator of around 70 sun with a one cm2 standard monocrystalline Si solar cell and conducted various preliminary experiments. The results that we observed are noteworthy as follows: at medium concentration, if the temperature is not controlled well very rapid degradation or even null-functioning of the cell is un-avoidable. Without a thermal sink structure at the back side of the cell, the temperature can raise up to 350 °C in minutes. With the metal sink structure covering the cell, the temperature rises up to 175 °C within a few minutes. However, with a thermal water-cooling system that we constructed, the equilibrium temperature can be kept at 65 °C, which can further be adjusted by proper thermal sink and cooling design.

One of the main weaknesses of Si-based Photovoltaic (PV) solar modules is the sensitivity of their efficiency to module (cell) temperature. Especially in locations with long hot seasons, the efficiency loss of PVs due to high temperatures should be considered carefully. Thermal modelling is a method to predict the performance of a PV module using essentially the 1st law of thermodynamics and available data. In this paper, a transient thermal model is described, which considers hourly meteorological data, including wind speed and direction, module parameters, and locational information. In transient analysis, the heat capacity value of PV panel is required, but it is not a parameter specified in the manufacturer's datasheet. Experiments on the heat capacity of PV modules are missing in the literature. The thermal model provides verified performance analysis for a poly-c-Si PV module installed in Ankara, Turkey, with a calculated heat capacity value. And a sensitivity analysis for the heat capacity of the transient thermal model is performed. It is found that the model results are almost invariant under changing module heat capacity values.

In a techno-economic analysis, to reach truthful feasibilities, accurate performance calculation of PV systems is a must. There are many models/calculation schemes to estimate PV module performances. In this study, we compare the estimation of three software (PV*Sol, PVsyst, HelioScope) using a whole year field data obtained in Ankara, for five-module types. The reason for these choices of the software is their common utilization by designers, financing bodies and investors. The results of the preliminary analysis showed that the calculation methods for the PV systems performances should be carefully evaluated and used as they contain quite many located dependent empirical parameters, and distinctions in the fabricated modules. Therefore, the present article focuses on the systems that use the module types of Mono-Si, Poly-Si, μc-Si/a-Si, CIS, and HIT. The comparisons showed that the estimation accuracies of the software are reasonable, yet the software Helioscope performs better than the others for the weather conditions of Ankara, Middle Anatolia.

Nine years outdoor testing of the two on-grid PV systems at Central Anatolia under the same ambient conditions is very important to be discovered toward transition to renewables. The systems consist of a monocrystalline silicon and micro-crystalline silicon based amorphous thin film PV technologies. The analyses are carried out on monthly based using the outdoor efficiencies. In addition, degradation rates of these systems are calculated and compared with each other and also with international literature. It is also compared the results using the degradation rates of an earlier study carried out using measurements of a shorter period of time.

To estimate the performance of the photovoltaic power systems is the key issue in their techno-economic feasibility analysis. Performances, on the other hand, strongly depends on the module temperatures of the photovoltaic systems. In this study, we evaluated the performance of ten different module temperature estimation models using the measured outdoor data of five different modules. The modules are installed at the rooftop of a building located at Central Anatolia where the climate is cold and semi-arid. The results showed that the models having smaller number of parameters perform better than the others. We concluded that such analysis should be carried out at different ambient conditions so that the best performing models for the site can be obtained. Another outcome of the study is that the seasonal evaluation of the performance of the models should be carried out.

In a techno-economic analysis, to reach truthful feasibilities, accurate performance calculations of PV systems are a must. There are many models/calculation schemes to estimate PV module performances. In this study, we compare the estimation of three software (PV*Sol, PVSyst, HelioScope) using a whole year field data obtained in Ankara, for five module types (Mono-Si, Poly-Si, µc-Si/a-Si, CIS, and HIT). Our analysis showed that the calculation schemes of the performances should be carefully evaluated and used as they contain quite many located dependent empirical parameters, and distinctions in the fabricated modules. The comparisons showed that the estimation accuracies of the software are reasonable, yet software Helioscope performs better than the others for weather conditions of Ankara, Middle Anatolia.

The transition in the energy sector has started with the growing population leading to the growing energy demands. The use of photovoltaic (PV) technologies has become a crucial way to meet energy demand. There are many ongoing studies for increasing the efficiency of commercial PV modules. One way to increase the energy yield of the PV modules is to use bifacial solar panels by capturing the rear side illumination as well. One of the challenges for estimating the bifacial module performances is to calculate the solar irradiation impinging on the rear side. Many models presented up to now require high computational power, and they are challenging to implement real-life conditions. In this paper, a simple physical modeling approach is presented to calculate the rear side solar irradiation incident on the bifacial modules. For the rear side irradiance estimation, the maximum difference between the measured and calculated rear side irradiance value is approximately 10 W/m(2). The model does not require high computational skills since it is neither focused on the view factor nor ray tracing methodologies but instead uses solar geometry. The yield of the module is also modeled, calculated, and compared with the measurements.