Analysis of spectral irradiance variation in northern Europe using average photon energy distributions

One major factor affecting the energy yield of photovoltaic modules is the spectral distribution of incident solar radiation. As spectral irradiance data is scarce, this study provides further documentation of recorded spectra at tilt angle 30°– 45°over a period from one to several years, with the resulting distributions of average photon energy (APE) in the 350–1050 nm wavelength range, from five locations in northern Europe. The results show a general trend of higher monthly APE values in summer and lower values in winter, with more pronounced APE variation at increasing latitude. Compared to the reference APE value of 1.88 eV, the largest variation in monthly APE is seen for the northernmost location of Grimstad, Norway, ranging from 1.82 eV to 1.93 eV between January and July with an annual average APE of 1.90 eV. The smallest variation is found for Merklingen, Germany, ranging from 1.86 eV to 1.88 eV between March and July, with an annual average APE of 1.86 eV. Comparing the annual average APE values of the various locations, the study shows a slightly blue-shifted spectrum for Berlin, Enschede and Grimstad, whereas Merklingen experiences a slightly red-shifted spectrum and the APE at Utrecht is similar to the standard reference spectrum. The simulations through SMARTS show air mass, water vapor and aerosols as the major parameters affecting the spectrum. During the winter months, distinct contributions from both clear and cloudy sky conditions result in a bi-modal APE distribution for all locations, which is not observed during the summer months. Analysis of APE demonstrates different site-specific behaviors, even though all sites are categorized in the same Köppen–Geiger (KG) climate class. These differences arise mainly due to atmospheric factors, whereas dissimilarity in albedo conditions, plane of tilt and instrumentation also have some contributions

Ray Tracing of Bent Applications of Luminescent Solar Concentrator PV Modules

Flat luminescent solar concentrator PV (LSC-PV) devices have in development for nearly 45 years. However, to enhance their integration potential in buildings and vehicles, this study is focused on bent LSC-PV devices. LSC PV modules with a 20 times20 mathrm{cm} 2 top surface area and 6 different curvatures (k, from 1 to 10 mathrm{m} {-1}) have been designed in Dassault Systèmes Solidworks and simulated by means of ray tracing in Synopsys LightTools. These modules are 20 mm thick, are made of PMMA with 110 parts per million (ppm) of Lumogen Red 305 dye, and silicon solar cells attached only to their rectangular edges with a total PV cell coverage area of 80 cm2 per module. The simulation results show better optical and electrical performances for the bent LSC-PV modules than for flat planar modules. The performance increases with the increase of curvature; for instance, an LSC-PV module with a curvature of mathrm{k}=10 mathrm{m} {-1} is 40% more efficient than a flat reference. Furthermore, in this study, the effect of reflection layers and sizing of the front surface of the bent LSC PV modules on their performance is investigated

An Empirical Model for Rack-Mounted PV Module Temperatures for Southeast Asian Locations Evaluated for Minute Time Scales

10.1109/JPHOTOV.2015.2405762IEEE Journal of Photovoltaics53774-78

Leaf roof - Designing luminescent solar concentrating PV roof tiles

The Leaf Roof project on the design features of PV roof tiles using Luminescent Solar Concentrator (LSC) technology [1] has resulted in a functional prototype. The results are presented in the context of industrial product design with a focus on the aesthetic aspects of LSCs [2]. This paper outlines the design of Leaf Roof tiles under consideration of simulation results, experimental measurements on dyes' absorption spectra, and the energy performance of Leaf Roof elements in the context of their geometry and colors

Leaf roof - Designing luminescent solar concentrating PV roof tiles

The Leaf Roof project on the design features of PV roof tiles using Luminescent Solar Concentrator (LSC) technology [1] has resulted in a functional prototype. The results are presented in the context of industrial product design with a focus on the aesthetic aspects of LSCs [2]. This paper outlines the design of Leaf Roof tiles under consideration of simulation results, experimental measurements on dyes' absorption spectra, and the energy performance of Leaf Roof elements in the context of their geometry and colors