The First Design and Application of Floating Photovoltaic (FPV) Energy Generation Systems in Turkey with Structural and Electrical Performance
Mustafa Kemal Kaymak, Ahmet Duran Şahin
Abstract Greenhouse gas (GHG) emissions are primarily due to the exploitation of fossil fuel as an energy source, and one of the energy alternatives for the reduction of emissions is the use of renewable energy sources; one of these is solar irradiation conversion to useable clean energy. In the city of Istanbul, floating photovoltaic (FPV) installation started in 2017, on one of the lakes with an extensive surface area, Büyükçekmece, which supplies water to the city. To reduce evaporation losses and to generate electricity, two FPV prototypes were installed, with capacities of 9 and 90 kWp. Due to the location and climate of Büyükçekmece Lake, all system components including steel construction, metal sheet, maintenance way, connecting parts, and pontoons must resist extreme weather conditions, especially harsh waves and high wind loads. This paper is focused on a survey of the survival performance of the FPV system under real weather conditions without blockage of evaporation, just the reduction of it. Stress and strain tests were also applied to pontoons, one of the vital components for floating systems. The elasticity module, yield limit and tensile strength were evaluated as 0.42 GPA, 11.5 mPA, and 19 mPA, respectively. The wave height was calculated by means of four practical relationships, taking the lake’s distinctive characteristics into consideration. The electricity generation of 90 kWp FPV measured for June 2017 was 5189 kWh. The structural and electri-cal performance results from these systems in the city of Istanbul could be applied further to large scale FPV applications in water reservoirs nationally and internationally.
Keywords Solar energy , Floating photovoltaic, Lake, Wave, Climate, Mitigation
International Journal of Precision Engineering and Manufacturing-Green Technology (2022) 9:827–839
https://doi.org/10.1007/s40684-021-00369-w
Problems encountered with floating photovoltaic systems under real conditions: A new FPV concept and novel solutions
Mustafa Kemal Kaymak, Ahmet Duran Şahin
Abstract Floating photovoltaic power plants represent one contemporary new alternative to terrestrial PV systems. In this study, which was based on an examination of three different floating photovoltaic systems that were installed on Büyükçekmece Lake in Istanbul with an output of 9 kWp, 90 kWp and 30 kWp, we carried out an assessment of the difficulties and critical faults that can arise with such systems. During the course of the study, it was found that warpage of floating photovoltaic elements as a consequence of harsh wave action is one of the most serious problems that may be encountered. Tests of structural fixity, one-way motion and semi-flexible fitting elements revealed that they are not suitable for floating photovoltaic systems. A comparison of previously installed systems with our new 30 kWp floating photovoltaic designs indicated that the latter were robust and sustainable even with the severe wind and wave conditions on Büyükçekmece Lake for the period of research, which ran between July 2018 and April 2020. Our research also indicated that most of the well-known float and frequently used designs for floating photovoltaic systems are not sufficiently robust for severe environmental conditions. This study provides two significant yet contrary outcomes for floating photovoltaic designs, namely that systems as a whole must be flexible while individual units need to remain stable.
Keywords Floating photovoltaic systems, Solar energy, Severe weather conditions, Lakes, Wave load
Sustainable Energy Technologies and Assessments 47 (2021) 101504
https://doi.org/10.1016/j.seta.2021.101504
Floating and terrestrial photovoltaic systems comparison under extreme weather conditions
Mustafa Kemal Kaymak, Ahmet Duran Şahin
Abstract Greenhouse gas emissions are primarily caused by the exploitation of fossil fuels as an energy source, and one way to reduce those emissions is to utilize renewable energies such as solar irradiation conversion. In the city of Istanbul, two Floating Photovoltaic (FPV) prototypes were installed in 2016 on Büyükçekmece Lake, a large body of water that supplies fresh water to the city, as a means of both reducing evaporation loss and generating electricity. The systems had capacities of 90 and 30 kWp, respectively. Additionally, a 30 kWp capacity Terrestrial Photovoltaic (TPV) system was installed to facilitate a comparison of electricity generation between the systems. FPV systems, which have been hailed as new alternatives to TPVs, are generally set up on calm bodies of water. Büyükçekmece Lake, however, is open to severe weather conditions, including wind-driven waves that can reach heights of 1.5 to 3.0 m, which can lead to unbalanced load distributions on FPVs and damage to the systems. Of the two systems that were installed, one of them had a semi-flexible frame, but that prototype ultimately failed as a result of wave action. However, a new design referred to here as a “fully flexible FPV system,” held up under the severe conditions on the lake. The total amount of electricity generated by the first 90 kWp FPV system was approximately 17 400 kWh and the capacity factor was around 42% for a period of 467 hours between May 19, 2017 and July 4, 2017. Between November 21, 2018 and December 22, 2018, the second FPV system generated 309 kWh, while the TPV had an output of 365 kWh. The capacity factors for the systems were calculated as 14.51% and 17.15%, respectively. The most important finding of these studies concerns in order for FPV systems to operate safely in severe weather conditions that can result in unbalanced load distributions, the units that comprise the system must be able to float independently, and the system connections must be flexible. Moreover, based on the measured values it was found that in terms of electricity output, neither FPVs nor TPVs have a major advantage when compared to each other.
Keywords Floating photovoltaic systems, Severe weather conditions, Solar energy, Sustainable energy
International Journal of Energy Research 2022;46:20719–20727
https://doi.org/10.1002/er.8627
Comprehensive Analysis of Extreme Meteorological Conditions for the Safety and Reliability of Floating Photovoltaic Systems: A Case on the Mediterranean Coast.
Mehmet Seren Korkmaz, Emir Toker, Ahmet Duran Şahin
Abstract In recent decades, renewable energy projects have required careful consideration of environmental factors. This study investigates the impact of a mid-latitude cyclone on planned floating photovoltaic (FPV) facilities in Antalya, Turkey, focusing on the severe thunderstorm events that brought heavy rainfall and tornadoes in January 2019. Synoptic analysis reveals a deep cut-off low over the Genoa Gulf, causing trough formation and vertical cloud development due to moisture convergence. Warm air advection pushed an unstable thunderstorm system northward along an occluded front. Using the Weather Research and Forecast (WRF) model, sensitivity analysis is conducted, highlighting regional variations in wind speeds. The model outputs are compared with observations, identifying the best configuration using statistical indicators. The Mellor–Yamada–Janjic (MYJ) planetary boundary layer (PBL) scheme and the Milbrandt microphysics scheme produced better results in the western and central regions. The model output of the best configurations is used to calculate regional wave characteristics with a modified Shore Protection Manual (SPM) method for water reservoirs. These findings offer invaluable insights for future FPV projects, providing a better understanding of how to address challenges posed by extreme weather conditions and how to enhance system safety and reliability.
Keywords Mediterranean, Extreme weather, Floating photovoltaics, WRF, Meteorological analysis, Wave characteristics
Sustainability 2023, 15, 14077
https://doi.org/10.3390/su151914077
Temperature and precipitation extremes’ variability in Turkey
Nida Doğan Çiftçi, Ahmet Duran Şahin
Abstract Extreme weather events have become more frequent since the second half of the twentieth century. This study examines the long-term changes in temperature and precipitation extremes in two sequential periods over the period 1960–2019 using daily maximum, minimum, and mean temperatures and total precipitation for the four conventional seasons in Turkey. First, the Probability Density Function (PDF) for the mean temperature and precipitation are analyzed for the sequential periods. Second, extreme and relative value indices of the Expert Team on Climate Change Detection and Indices (ETCCDI) are used to evaluate changes in climate regions of Turkey for the considered period. A general upward trend in temperature indices is seen over the regions, but precipitation indices have more variable outcomes. The monthly minimum value of the daily maximum temperature (TXn) index has a 2 °C decades−1 increase, and except for five stations, there is a 1 °C decades−1 increase between the two sequential periods. While the annual total precipitation (RR ≥ 1 mm) (PRCPTOT) index has increased by 50 mm in the Black Sea, Continental-b and, Continental-c regions it has decreased in Mediterranean, Continental-a, and Transition regions. Similarly, very wet days (RR > 95th percentile) (R95p) and extremely wet days (RR > 99th percentile) (R99p) indices confirmed that the regions have not experienced an increase in extreme precipitation during the second half.
Meteorology and Atmospheric Physics (2023) 135:40
https://doi.org/10.1007/s00703-023-00976-z
Implications of Climate Change on Wind Energy Potential
Tolga Kara, Ahmet Duran Şahin
Abstract This study examines the crucial role of wind energy in mitigating global warming and promoting sustainable energy development, with a focus on the impact of climate change on wind power potential. While technological progress has facilitated the expansion of the industry, it is crucial to continue making advancements to reduce the life-cycle emissions of wind turbines and ensure their long-term sustainability. Temporal discontinuities present a significant challenge for renewable energy sources. This study highlights the potential of hybrid systems to provide consistent energy output from wind sources. It also examines the variability in wind patterns caused by climate change, acknowledging that outcomes vary depending on geographic contexts, modeling approaches, and climate projections. Notably, inconsistencies in wind speed projections from downscaled general circulation models introduce uncertainties. While specific regions, such as North America, project an increase in wind speeds, others, such as the Mediterranean, face a potential decrease. Of particular note is the forecast for a potential long-term increase in wind speeds in Northern Europe. In conclusion, the wind energy industry displays considerable potential for growth, driven by technological advancements. However, the complexities resulting from climate change necessitate further research. Such insights are crucial for informed energy policy formulation and sustainable industry progress.
Keywords Climate change, Hybrid system, Wind energy, Wind energy Potential, Wind Speed
Sustainability 2023,15, 14822
https://doi.org/10.3390/su152014822
Quantifying Sectoral Carbon Footprints in Türkiye’s Largest Metropolitan Cities: A Monte Carlo Simulation Approach
Sena Ecem Yakut Şevik, Ahmet Duran Şahin
Abstract Urbanization is a substantial contributor to greenhouse gas (GHG) emissions, a pivotal factor in climate change. Climate change represents a global predicament impacting all nations, necessitating collaboration among numerous countries to curtail GHG emissions. An essential step to overcome this problem is the accurate measurement, calculation, and modelling of the amount of damage inflicted on the atmosphere. Therefore, carbon footprints (CFs) originating from various sources are calculated. This study calculates the CF of different sectors in metropolitan cities in Türkiye, which are Istanbul, Ankara, and Izmir, for the years 2015–2020 using the Tier 1 and Tier 2 approaches outlined in the Intergovernmental Panel on Climate Change (IPCC) methodology. Additionally, to account for uncertainties in activity data and emission factors and calculate the potential emission range, a Monte Carlo simulation (MCS) was conducted. Analysis of Tier 1 results revealed the highest emissions consistently occurring in Istanbul across all years, while emissions from other cities exhibited variability annually. Notably, average MCS results surpassed the total emission quantities derived at the study’s conclusion for all cities and years, underscoring the influence of uncertainties. The study results align with the calculated 95% confidence interval, affirming the robustness within the specified statistical framework
Keywords Greenhouse Gases; Climate Change; Carbon Footprint; Türkiye;Mmetropolitan Centers; Monte Carlo Simulation
Sustainability 2024, 16(5), 1730
https://doi.org/10.3390/su16051730
Numerical simulation of extreme wave-wind conditions effects on a real field floating photovoltaic power system application
Ali Osman Mut, Mustafa Kemal Kaymak, Ahmet Duran Şahin
Abstract The simulation of wave and wind loads on the 30 kWp Floating Photovoltaic system under extreme wind conditions was carried out using the Computational Fluid Dynamics method. The study focuses on real application of floating power plant, and the information obtained from the analysis is expected to contribute to the design of new or existing systems. Calculations demonstrate wave deformation in severe wind, yielding heterogeneous force distributions. The compressed air flow lines align with areas characterized by high-speed flow, with wind speeds ranging from 30 to 50 m/s. The wave kinetic energy increases due to the wind, resulting in high forces being applied to the surface of the Floating Photovoltaic platform. Turbulence Kinetic Energy exhibits higher values in front of and on the surface of the platform due to the disruption of the airflow. As a result of direct interaction with waves and wind, the front section of the floating system experiences significantly higher loads. The total pressure on the entire surface of the floating platform reaches maximum values of up to 38.677 kN/m2. When compared with various analytical methods, it has been observed that the Goda and Morison methods yield closer results. This discrepancy is believed to stem from the omission of wind interactions and platform structure considerations in the analytical methods. Overall, the analysis highlights the importance of considering wind and wave interactions in the design and protection of Floating Photovoltaic systems, and the findings contribute to the advancement of these systems.
Keywords Computational Fluid Dynamics · Floating Photovoltaic · Solar Energy · Wind-Wave Load · Turbulence Kinetic Energy · Wind-Wave Interaction
International Journal of Environmental Science and Technology 2024