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DOE OSTI · 3026700

Outdoor Deployment Data for a Four-Terminal GaAs//Si Tandem Solar Mini-Module

Springer, Martin [National Laboratory of the Rockies] (ORCID:000000016803108X)·Witteck, Robert [National Laboratory of the Rockies] (ORCID:0000000187162616)·Silverman, Tim [National Laboratory of the Rockies] (ORCID:0000000349517994)·Geisz, John [National Laboratory of the Rockies] (ORCID:000000034818653X)·McMahon, Bill [National Laboratory of the Rockies] (ORCID:0000000150362032)·Warren, Emily [National Laboratory of the Rockies] (ORCID:0000000185687881)
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Abstract

This dataset contains the complete outdoor measurement and analysis data for a mechanically stacked, four-terminal (4T) gallium arsenide (GaAs)//silicon (Si) tandem solar mini-module deployed from October 2019 to January 2021 at the Solar Radiation Research Laboratory (SRRL) in Golden, Colorado, USA. The data support a performance modeling and degradation analysis framework for tandem photovoltaic devices, as described in the accompanying publication. The dataset includes: (1) current–voltage (J–V) characteristics of each sub-cell measured approximately every five minutes, with extracted performance parameters; (2) spectral irradiance from an EKO MS-710 WISER spectroradiometer, along with derived spectral mismatch ratios (SMR) and average photon energy (APE); (3) one-minute resolution meteorological data from the co-located SRRL weather station and GPS-derived precipitable water vapor (PWV); (4) pre-deployment laboratory characterization (external quantum efficiency, J–V curves, standard test conditions parameters); (5) outdoor-extracted temperature and PWV correction coefficients; and (6) PVcircuit equivalent-circuit simulation outputs used for model validation. Degradation rates of −4.1 ± 0.2 %/year (GaAs) and −2.5 ± 0.9 %/year (Si) were determined using a filtering and normalization methodology adapted for fixed-tilt tandem modules. All data are provided in open, portable formats (Apache Parquet, CSV, JSON) to enable full reproducibility of the published analysis.

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14 SOLAR ENERGY36 MATERIALS SCIENCEcurrent-voltage characteristicsdegradation ratefour-terminalGaAs//Simini-moduleoutdoor deploymentperformance modelingPVcircuitsolarspectral mismatchstandard test conditionstandem photovoltaicstemperature coefficients

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Springer, Martin [National Laboratory of the Rockies] (ORCID:000000016803108X), Witteck, Robert [National Laboratory of the Rockies] (ORCID:0000000187162616), Silverman, Tim [National Laboratory of the Rockies] (ORCID:0000000349517994), Geisz, John [National Laboratory of the Rockies] (ORCID:000000034818653X), McMahon, Bill [National Laboratory of the Rockies] (ORCID:0000000150362032), Warren, Emily [National Laboratory of the Rockies] (ORCID:0000000185687881). 2026-04-03. Outdoor Deployment Data for a Four-Terminal GaAs//Si Tandem Solar Mini-Module. https://doi.org/10.7799/3026700

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