Sürdürülebilir Kalkınma Amaçları
Yayınlar
- BildiriYayıncıda açık erişim2022Shading Effect of Transparent Photovoltaic Panels on Crops Underneath Agrivoltaic Systems
Esmaeilzad, Nasim Seyedpour; Dino, Ipek Gursel; Güney, Dilara; Yildirim, Yusuf Ersoy; Turan, Rasit; Özden, Talat; Amaducci, S
Agrivoltaic systems combine soil-grown crops with photovoltaic (PV) panels erected several meters above the ground. Combining solar panels and food crops on the same land can maximize land utilization. Under the PV panels, however, microclimate factors like solar radiation, air temperature, humidity, and soil temperature change. An agrivoltaic system must optimize sunlight sharing between solar panels and crops to maximize food energy production. It has been challenging to improve and analyze the performance of agrivoltaic systems due to the lack of a defined crop-specific parameter. In this work, we present a practical option to partially replace bifacial modules with semi-transparent ones, providing comparable levels of crop protection and greater climate change resilience while generating green energy and increasing land-use efficiency. The agrivoltaic system must be tailored to satisfy the needs of crops. For this purpose, a simulation model was conducted, which examined the impact of module transparency and cell layout based on light availability.
- MakaleAçık Erişim2020One-year performance evaluation of two newly developed back-contact solar modules in two different climates
Ozden, Talat; Carr, Anna J.; Geerligs, Bart (L.J.); Turan, Rasit; Akinoglu, Bulent G.
To a certain extent, the photovoltaics industry is well developed, and the performance and expected yield of standard photovoltaic modules are well documented and researched. However, newer more efficient photovoltaic cell and module technologies are being developed all over the world. Outdoor testing of new photovoltaic technologies is very important to understand and validate their reliability and performance under different environmental conditions. For the first time, one year of monitored performance data is presented and analyzed for two high efficiencies interdigitated back contact prototype mini-modules at different locations, having different climates. The test results of a commercial heterojunction with intrinsic thin-layer” module are also presented for comparison. The results showed that the two mini-modules remained stable for the duration of the test period, and showed no signs of degradation. They did perform significantly differently due to the different climatic conditions. The results also show that the combination of ambient temperature difference together with relative humidity impacts the performance of the modules. Calculated outdoor yearly efficiencies are 19.05% and 18.36% for two integrated back contact mini-modules tested in Petten-Netherland and Ankara-Turkey, respectively. The temperature coefficients of the modules are also calculated and compared with two commercial photovoltaic modules.
- BildiriAçık Erişim2017Effect of Ambient Conditions on Monthly Performances of Three Different PV Arrays
Özden, Talat; Akinoglu, Bulent G.; Turan, Rasit; Martinez, V; Gonzalez, J
Solar PV cells may be mainly divided into two parts as crystalline and thin film. Mono-crystalline silicon (e.g. Mono-Si) and microcrystalline based amorphous silicon and other thin films (e.g. gc-Si/a-Si and CdTe thin films) are widely used PV cells in the arrays. The outdoor performances of these systems depend on some climatic parameters and conditions, and it is important to understand how the monthly efficiencies vary with these parameters. In the present study, the data obtained from three grid connected PV arrays of Mono Si, a-Si/p.c-Si and CdTe thin film that were operated for 41 months in Ankara-Turkey is analyzed. The results showed that Mono-Si an-ay performance depends on the 5 parameters of outdoor climatic conditions while a-Si/gc-Si and CdTe thin film arrays performances arc not significantly affected by the variation of the climatic parameters. The possible reasons are discussed in details.
- MakaleAçık Erişim2017Long term outdoor performances of three different on-grid PV arrays in central Anatolia – An extended analysis
Ozden, Talat; Akinoglu, Bulent G.; Turan, Rasit
Long term outdoor testing of the PV systems at different climatic conditions or different systems under the same ambient conditions are extremely important in producing policies for the transition to renewables. The present research is the testing of three different PV systems under the same climatic conditions of central Anatolia, after four years of operation. The systems consist of a mono-Si, an a-Si thin film and a CdTe thin film arrays. Different calculation procedures of the input solar irradiation on tilted surface are used for comparison. Performances together with degradation rates are computed using different procedures and also using the measured solar data of 20 km away from the installed systems. The accuracy is verified using 4 months of simultaneous measurements. The results showed that the aforementioned different input calculation procedures of the performances are important and determinant. The 44-months-average efficiencies of these three systems are calculated to be 11.86%, 6.40% and 5.30%, respectively. The degradation rates of these systems are obtained as 0.40%, 1.88% and 10.60%, respectively. Although the degradation rates that are calculated for the first two systems are quite similar to those appeared in the literature, CdTe system is considerably higher than those given in the literature.
- MakaleAçık Erişim2015Outdoor efficiency analyses and comparison of on-grid CdTe and μc-Si/a-Si thin-film PV systems for three years in Ankara - Turkey
Ozden, Talat; Yardim, Ugur; Akinoglu, Bulent G.; Turan, Rasit; Turan, R; Gunes, M; Sariciftci, NS; Varlikli, C
The present paper is mainly a comparison of the performances of two PV systems under outdoor conditions in Ankara. The systems are grid connected and consist of two PV arrays. The types of these PV arrays are CdTe thin film and amorphous silicon/micro-crystalline-based (μc-Si/a-Si) arrays. They are operated for 3 years; 2012-2014. Yearly averages of monthly efficiencies of these two systems working under the same ambient conditions are 6.88%, 6.65%, 6.80% and 6.64%, 5.86%, 5.25% for μc-Si/a-Si and CdTe, respectively. Using these values, simple calculation results for the degradation rates per year are about 0.39%/year and 6.98%/year, respectively for these two types of systems.
- MakaleAçık Erişim2015A low cost outdoor testing facility for detailed photovoltaic device performance characterization
Ogulgonen, Guvenc; Ozden, Talat; Yardim, Ugur; Turan, Rasit; Kincal, Serkan; Turan, R; Gunes, M; Sariciftci, NS; Varlikli, C
Long term outdoor performance monitoring is the ultimate method to capture the long term performance characteristics of PV devices. As time consuming as this process might be, it is the only way in which the local environmental condition versus PV device characteristics may be captured when making investment decisions. This data needs to be captured at least once through the seasonal cycle. It needs to be correlated to the environmental conditions, this monitoring climatic conditions is a requirement. Solar irradiation conditions must be monitored over a range of inclination angles - direct, diffuse and reflected components must be ideally captured separately. The panels must be held at maximum power generating point through the varying illumination conditions. Periodic IV traces must be captured, in addition to the power output to understand mechanisms of degradation, if present. Furthermore, the IV curves must be summarized in terms of relevant performance metrics. This work describes an outdoor testing facility that addresses all the aforementioned requirements. Reliable equipment selections coupled with adequate modelling strategies allow for the generation of a robust and accessible database of performance data.