The book is devoted to the spatial characterization of solar cells and PV modules. It is written both as a monograph as well as a succinct guide for the state-of-the-art spatial characterization techniques and approaches. Amongst the approaches discussed are visual imaging, electro- and photo-luminescence imaging, thermography, and light beam induced mapping techniques. Emphasis is given on the luminescence image acquisition and interpretation due to its great technological potential.
COBISS.SI-ID: 10931796
In the first part a review of methods and simulators in the field of optical modeling and simulations of thin-film solar cells is given. We introdiuce an idea of a coupled modeling approach. We show simulation results of rigorous optical simulations of Si solar cells including nanotextures, employing a model of realistic layer growth. Furthermore, simulations of organic solar cells including macrotextures were carried out with simulator CROWM.
COBISS.SI-ID: 10835540
The paper presents a new PV module performance model with separate consideration of diffuse and direct light including solar incident angle. The new model requires additional measurement of diffuse irradiance, but simplicity is maintained using simple equations with low number of fitting coefficients. The model was evaluated with a mc-Si and CIGS PV module, based on outdoor monitoring data in Ljubljana. The new model was compared to two other heuristic models and a RMSE in eight snowless month period of 3.6 % was observed, on average 1 % less than that of the compared models. Much larger improvement with the new model is obtained at lower irradiances. The new model assures higher accuracy of PV system output power prediction and thus higher reliability of PV system fault detection applications.
COBISS.SI-ID: 10925652
In this study we analyze and discuss the optical properties of various tandem architectures: mechanically stacked (four-terminal) and monolithically integrated (two-terminal) tandem devices, consisting of a methyl ammonium lead triiodide (CH3NH3PbI3) perovskite top solar cell and a crystalline silicon bottom solar cell. We provide layer thickness optimization guidelines and give estimates of the maximum tandem efficiencies based on state-of-the-art sub cells. We use experimental complex refractive index spectra for all involved materials as input data for an in-house developed optical simulator CROWM. Our characterization based simulations forecast that with optimized layer thicknesses the four-terminal configuration enables efficiencies over 30 %, well above the current single-junction crystalline silicon cell record of 25.6 %. Efficiencies over 30 % can also be achieved with a two-terminal monolithic integration of the sub-cells, combined with proper selection of layer thicknesses.
COBISS.SI-ID: 10949972
A unique non-destructive characterization method for apparent bandgap imaging in photovoltaic (PV) devices based on acquisition of two electroluminescence (EL) images in different spectral ranges is presented. The method consists of a calibration procedure and a bandgap imaging procedure. Calibration has to be performed once per module type and EL imaging setup, and must provide a relation between the bandgap and the ratio between two spectrally independent EL images. After calibration, bandgap imaging only requires acquisition of two spectrally independent EL images followed by image processing, making the method very fast and suitable for in-line PV module characterization with regard to spatial (in)homogeneity and production process stability. The method is demonstrated on a commercial state-of-the-art Cu(In,Ga) Se2 PV module where apparent bandgap fluctuations between 1.07 and 1.15 eV are detected.
COBISS.SI-ID: 11645780