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Title: Effect of Atmospheric Absorption Bands on the Optimal Design of Multijunction Solar Cells

Abstract

Designing terrestrial multijunction (MJ) cells with 5+ junctions is challenging, in part because the presence of atmospheric absorption bands creates a design space with numerous local maxima. Here we introduce a new taxonomical structure which facilitates both numerical convergence and the visualization of the resulting designs.

Authors:
; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
OSTI Identifier:
1369131
Report Number(s):
NREL/PO-5J00-68603
DOE Contract Number:
AC36-08GO28308
Resource Type:
Conference
Resource Relation:
Conference: Presented at the 2017 IEEE Photovoltaic Specialists Conference (PVSC-44), 25-30 June 2017, Washington, D.C.
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; multijunction solar cells; numerical modeling; atmospheric absorption bands; current matching

Citation Formats

McMahon, William E., Friedman, Daniel J., and Geisz, John F. Effect of Atmospheric Absorption Bands on the Optimal Design of Multijunction Solar Cells. United States: N. p., 2017. Web.
McMahon, William E., Friedman, Daniel J., & Geisz, John F. Effect of Atmospheric Absorption Bands on the Optimal Design of Multijunction Solar Cells. United States.
McMahon, William E., Friedman, Daniel J., and Geisz, John F. Mon . "Effect of Atmospheric Absorption Bands on the Optimal Design of Multijunction Solar Cells". United States. doi:. https://www.osti.gov/servlets/purl/1369131.
@article{osti_1369131,
title = {Effect of Atmospheric Absorption Bands on the Optimal Design of Multijunction Solar Cells},
author = {McMahon, William E. and Friedman, Daniel J. and Geisz, John F.},
abstractNote = {Designing terrestrial multijunction (MJ) cells with 5+ junctions is challenging, in part because the presence of atmospheric absorption bands creates a design space with numerous local maxima. Here we introduce a new taxonomical structure which facilitates both numerical convergence and the visualization of the resulting designs.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jun 26 00:00:00 EDT 2017},
month = {Mon Jun 26 00:00:00 EDT 2017}
}

Conference:
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  • This paper re-examines the impact of atmospheric absorption bands on series-connected multijunction cell design, motivated by the numerous local efficiency maxima that appear as the number of junctions is increased. Some of the local maxima are related to the bottom subcell bandgap and are already well understood: As the bottom subcell bandgap is varied, a local efficiency maximum is produced wherever the bottom cell bandgap crosses an atmospheric absorption band. The optimal cell designs at these local maxima are generally current matched, such that all subcells have nearly the same short-circuit current. We systematically describe additional local maxima that occurmore » wherever an upper subcell bandgap encounters an atmospheric absorption band. Moreover, these local maxima are not current matched and become more prevalent as the number of junctions increases, complicating the solution space for five-junction and six-junction designs. A systematic framework for describing this complexity is developed, and implications for numerical convergence are discussed.« less
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