{"@type": "dcat:Dataset", "accessLevel": "public", "bureauCode": ["019:20"], "contactPoint": {"@type": "vcard:Contact", "fn": "Martin Springer", "hasEmail": "mailto:Martin.Springer@nlr.gov"}, "dataQuality": true, "description": "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\u2013voltage (J\u2013V) 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\u2013V 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 \u22124.1 \u00b1 0.2 %/year (GaAs) and \u22122.5 \u00b1 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.", "distribution": [{"@type": "dcat:Distribution", "accessURL": "https://data.nlr.gov/system/files/324/1775237271-gaas-si-tandem-outdoor-deployment-data.zip", "description": "The dataset comprises 32 files (~3.6 GB) organized into six subdirectories: module_performance/ contains Parquet files with scalar J\u2013V parameters (Voc, Isc, Pmp) and environmental conditions for each sub-cell measurement, plus CSV files with full IV curve data points; spectral/ contains Parquet files of OTF-corrected spectroradiometer data (807 wavelength channels, 343\u20131650 nm), derived spectral mismatch ratios, and average photon energy; meteorological/ contains a Parquet file of one-minute SRRL weather station data (27 selected channels from 236 available) and a CSV of GPS-derived precipitable water vapor; lab_reference/ contains the pre-deployment laboratory characterization (EQE, IV, STC parameters) in Excel and CSV formats, plus the ASTM G173 AM1.5G reference spectrum; coefficients/ contains CSV files of outdoor-extracted temperature and PWV correction coefficients with a JSON summary; and model/ contains PVcircuit simulation outputs (JSON and Parquet) for measured-vs.-modeled comparisons of power, Voc, and temperature-dependent behavior. A machine-readable manifest.json lists all files with their paths and sizes.", "mediaType": "application/octet-stream", "title": "The dataset comprises 32 files (~3.6 GB) organized into six subdirectories: module_performance/ contains Parquet files with scalar J\u2013V parameters (Voc, Isc, Pmp) and environmental conditions for each sub-cell measurement, plus CSV files with full IV curve data points; spectral/ contains Parquet files of OTF-corrected spectroradiometer data (807 wavelength channels, 343\u20131650 nm), derived spectral mismatch ratios, and average photon energy; meteorological/ contains a Parquet file of one-minute SRRL weather station data (27 selected channels from 236 available) and a CSV of GPS-derived precipitable water vapor; lab_reference/ contains the pre-deployment laboratory characterization (EQE, IV, STC parameters) in Excel and CSV formats, plus the ASTM G173 AM1.5G reference spectrum; coefficients/ contains CSV files of outdoor-extracted temperature and PWV correction coefficients with a JSON summary; and model/ contains PVcircuit simulation outputs (JSON and Parquet) for measured-vs.-modeled comparisons of power, Voc, and temperature-dependent behavior. A machine-readable manifest.json lists all files with their paths and sizes."}], "identifier": "https://data.openei.org/submissions/8654", "issued": "2026-04-03T19:46:39Z", "keyword": ["tandem photovoltaics", "GaAs//Si", "four-terminal", "outdoor deployment", "degradation rate", "spectral mismatch", "performance modeling", "current-voltage characteristics", "solar", "mini-module", "standard test conditions", "temperature coefficients", "PVcircuit"], "landingPage": "https://data.nlr.gov/submissions/324", "license": "https://creativecommons.org/licenses/by/4.0/", "modified": "2026-04-03T20:22:54Z", "programCode": ["019:009"], "projectNumber": "38266", "projectTitle": "Tandem Photovoltaics Core", "publisher": {"@type": "org:Organization", "name": "National Laboratory of the Rockies"}, "title": "Outdoor Deployment Data for a Four-Terminal GaAs//Si Tandem Solar Mini-Module"}