The degradation rate plays an important role in predicting and assessing the long-term energy generation of photovoltaics (PV) systems. Many methods have been proposed for extracting from operational data PV systems, but most published approaches are susceptible to bias due inverter clipping, module soiling, temporary outages, seasonality, sensor degradation. In this paper, we propose a methodology determining leveraging available modeled clear-sky irradiance rather than site data, robust...

P-Type cuprous oxide (Cu2O) photoelectrodes prepared by the thermal oxidation of Cu foils exhibited open-circuit voltages in excess 800 mV nonaqueous regenerative photoelectrochemical cells. In contact with decamethylcobaltocene+/0 (Me10CoCp2+/0) redox couple, yielded voltage, Voc, values 820 and short-circuit current density, Jsc, 3.1 mA cm−2 under simulated air mass 1.5 illumination. The energy-conversion efficiency 1.5% was limited solution absorption optical reflection losses that...

The steady-state photoluminescence spectra of zinc phosphide (Zn3P2) wafers have revealed a fundamental indirect band gap at 1.38 eV, in close proximity to the direct 1.50 eV. These values are consistent with for and gaps obtained from analysis complex dielectric function deduced spectroscopic ellipsometric measurements. Bulk minority carrier lifetimes 20 ns were observed by time-resolved decay measurements, implying minority-carrier diffusion lengths ≥7 μm.

The energy-band alignment of epitaxial zb-ZnS(001)/α-Zn3P2(001) heterojunctions has been determined by measurement shifts in the phosphorus 2p and sulfur core-level binding energies for various thicknesses (0.6–2.2 nm) ZnS grown molecular beam epitaxy on Zn3P2. In addition, position valence-band maximum bulk Zn3P2 films was estimated using density functional theory calculations density-of-states. heterojunction observed to be type I, with a offset, ΔEV, −1.19 ± 0.07 eV, which is...

The economic return on investment of a commercial photovoltaic system depends greatly its performance over the long term and, hence, degradation rate. Many methods have been proposed for assessing rates from outdoor data. However, comparing reported values one analyst and research group to another requires common baseline performance; consistency between analysts can be challenge. An interlaboratory study was conducted involving different volunteer reporting same data using methodologies....

In this paper, we compare the accuracy of four bifacial irradiance models used in photovoltaic industry, by benchmarking them against field measurements. Using modeling tools bifacial_radiance (ray tracing), bifacialvf, pvfactors and PVSyst, modeled front- backside at two test sites: a fixed-tilt PV system installed Albuquerque, NM single-axis tracker Davis, CA. We found that all predicted annual energy impact gain within ±1% one another, fast view-factors-based matched more computationally...

Surface recombination velocities measured by time-resolved photoluminescence and compositions of Zn3P2 surfaces x-ray photoelectron spectroscopy (XPS) have been correlated for a series wet chemical etches substrates. substrates that were etched with Br2 in methanol exhibited surface velocity values 2.8 × 104 cm s−1, whereas further treated aqueous HF–H2O2 1.0 s−1. exposed to air 1 week 1.8 103 as well improved ideality metal/insulator/semiconductor devices.

Time-to-failure data from PV modules subjected to damp heat tests of different temperature and relative humidity conditions was compiled SunEdison literature reports. Analysis the led a power law model time-to-failure for in as follows: TTF = A * e^(Ea/kT) RH^ (n), where is time hours reach 20% module loss, 6.4e-10, Ea 0.89 ± 0.11 eV, n -2.2 0.8. Damp acceleration factors were then computed >2500 global typical meteorological year sets with reference standard 85°C 85% test condition. The...

The fabrication of a wafer-scale dislocation-free, fully relaxed single crystalline template for epitaxial growth is demonstrated. Transferring biaxially-strained InxGa1-xAs ultrathin films from InP substrates to handle support results in full strain relaxation and the unit cell assumes its bulk value. Our realization demonstrates ability control lattice parameter energy band structure layer compound semiconductors an unprecedented way. Detailed facts importance specialist readers are...

Differences in the current-voltage characteristics of photovoltaic (PV) modules connected series and parallel combinations lead to a loss system level power referred as "electrical mismatch". As result electrical mismatch, at maximum operating point PV is less than sum outputs if they were acting independently. In this study, PVM match python package was used model from two representative flash test datasets. Randomly sampling that dataset, variety systems configurations simulated using...

We report conformal, epitaxial growth of GaP layers on arrays Si microwires. Silicon wires grown using chlorosilane chemical vapor deposition were coated with by metal-organic deposition. The crystalline quality GaP/Si wire was assessed transmission electron microscopy and x-ray diffraction. Hall measurements photoluminescence show p- n-type doping high mobility bright optical emission. pn homojunction diodes planar reference samples photovoltaic response an open circuit voltage 660 mV.

The GPU-accelerated DataFrame library cuDF has become increasingly popular for data analytics applications due to its superior performance against CPU-based libraries such as Pandas. One of the frequently-used operations in dataframe manipulation is user-defined aggregate functions (UDAFs). UDAFs allow users define custom routines outside pre-defined (Sum(), Max(), Avg(), etc.)

Zinc phosphide (Zn <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> P xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) is a promising and earth-abundant alternative to traditional materials (e.g. CdTe, CIGS, a-Si) for thin film photovoltaics. We report the fabrication of Mg/Zn Schottky diodes with VOC values reaching 550 mV, JSC up 21.8 mA/cm <sup xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , photovoltaic efficiency 4.5%....

Predicted clear sky irradiance depends on atmospheric composition as well solar position and extraterrestrial irradiance. The effects of year to variations in were studied using measurements aerosol optical depth (AOD) precipitable water (Pwat) at seven locations the United States. Three models evaluated, including one that uses Linke turbidity (T <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">L</inf> ). This model was evaluated historical,...

Zinc phosphide (Zn <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> P xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) is a promising and earth-abundant alternative to traditional materials (e.g. CdTe, CIGS, a-Si) for thin film photovoltaics. The record solar energy conversion efficiency Zn cells of 6% (M. Bhushan et al., Appl. Phys. Lett., 1980) used Mg/Zn device geometry that required annealing reach peak performance. Here we report...

Solar resource measurements play a critical role in the assessment of long-term energy yield and valuation PV systems. Recent methods have focused on probability exceedance statistic (PXX) for annual insolation as part computing project risk. For example, P90 is value exceeded 90% time. However, small sample size values given location increases uncertainty distribution. To assess distribution values, we aggregate ground- satellite-based data continental United States from 1961-2017,...

Over the past several years, advances in manufacturing for thin film Cu(In,Ga)Se <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (CIGS) devices have enabled volume production of high efficiency solar material with good repeatability and uniformity. In this study, quantitative analysis advanced imaging techniques was used to evaluate uniformity electronic properties all-PVD CIGS cells. Combined EL DLIT suggests that series resistance top...

A two-dimensional model of an MR write head has been constructed using a finite element model. The includes the eddy currents as well nonlinear saturation recording material. field (deep gap field) was calculated function write-current frequency and amplitude for two recording-head materials, standard 80/20 NiFe high magnetization Ms material 50/50 NiFe. analysis also done in time domain compared with experimental data on response, both microloop apparatus impedance measurements. Fair...

Improved cell integration is a critical part of narrowing the gap between and module efficiencies. In this paper, we present methodology based distributed-element circuit analysis electroluminescence imaging for optimizing design solar metallization interconnection. The model on an array equivalent circuits, each representing 100×100 μm area thin film cell. A range designs are then compared within simulation framework to deliver predictions effect changes efficiency. optimized was tested...

Moisture induced degradation is a challenge facing flexible CIGS modules designs as the polymeric barriers usually have higher water vapor transmittance rate (WVTR) than rigid glass barriers. In process of module design, expected lifetime key point in selecting most appropriate However, correlation between common acceleration tests and still not well known. This work introduces method monitoring in-situ by recording sheet resistance when exposed to humidity temperature. An empirical...

Zinc phosphide (Zn <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> P xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> ) is a promising alternative to traditional materials (e.g. CIGS, CdTe, a-Si) for thin film photovoltaics. Open circuit voltage in Zn cells has been limited by Fermi-level pinning due surfaces states and heterojunction interdiffusion, motivating the need prepare interfaces that are electrically passive chemically inert....

In this study, we introduce a novel Photovoltaic Energy Performance (PV) modeling framework "PVOPEL" to study performance of PV array using cell level resolution ray tracing technique and the resulting system electrical response. Conventionally, tools model energy output given for unit, such as single module or row modules, make an approximation that scales with increasing size. While some factors affecting do scale linearly size, other mismatch losses nonlinearly based on shading scene...