TY - RPRT TI - Closing the Accuracy Gap in Tandem Photovoltaic Testing: An Accessible and Efficient Spectral Tuning Method Using LED-Based Simulators for Research Laboratories and Industry AU - Song, Tao [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000214390033) AU - Mack, Charles [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] AU - Brewer, Jeremy [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] AU - Geisz, John F. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:000000034818653X) AU - Williams, Rafell [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] AU - Friedman, Daniel J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000239678746) AU - Kopidakis, Nikos [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:000000018123317X) PY - 2025 DO - 10.1103/ccdk-8fcc UR - https://www.osti.gov/biblio/3014896 ID - 3014896 ER -