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Energy production advantage of independent subcell connection for multijunction photovoltaics

Warmann, Emily C. and Atwater, Harry A. (2016) Energy production advantage of independent subcell connection for multijunction photovoltaics. Energy Science and Engineering, 4 (4). pp. 235-244. ISSN 2050-0505. doi:10.1002/ese3.125.

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Increasing the number of subcells in a multijunction or “spectrum splitting” photovoltaic improves efficiency under the standard AM1.5D design spectrum, but it can lower efficiency under spectra that differ from the standard if the subcells are connected electrically in series. Using atmospheric data and the SMARTS multiple scattering and absorption model, we simulated sunny day spectra over 1 year for five locations in the United States and determined the annual energy production of spectrum splitting ensembles with 2–20 subcells connected electrically in series or independently. While electrically independent subcells have a small efficiency advantage over series-connected ensembles under the AM1.5D design spectrum, they have a pronounced energy production advantage under realistic spectra over 1 year. Simulated energy production increased with subcell number for the electrically independent ensembles, but it peaked at 8–10 subcells for those connected in series. Electrically independent ensembles with 20 subcells produce up to 27% more energy annually than the series-connected 20-subcell ensemble. This energy production advantage persists when clouds are accounted for.

Item Type:Article
Related URLs:
URLURL TypeDescription
Warmann, Emily C.0000-0002-2810-4608
Atwater, Harry A.0000-0001-9435-0201
Additional Information:© 2016 The Authors. Energy Science & Engineering published by the Society of Chemical Industry and John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Received: 5 January 2016; Revised: 16 May 2016; Accepted: 10 June 2016. This project was supported QESST via the National Science Foundation (NSF) and the Department of Energy (DOE) under NSF CA No. EEC-1041895, and also the Advanced Research Projects Agency-Energy (ARPA-E), U.S. Department of Energy, under Award Number DE-AR0000333. ECW acknowledges support from QESST and ARPA-E, and HAA was supported as part of the DOE “Light-Material Interactions in Energy Conversion” Energy Frontier Research Center under grant DE-SC0001293. Conflict of Interest: None declared.
Funding AgencyGrant Number
Department of Energy (DOE)DE-AR0000333
Department of Energy (DOE)DE-SC0001293
Subject Keywords:Energy production, multijunction solar cells, spectral variation, spectrum splitting
Issue or Number:4
Record Number:CaltechAUTHORS:20161103-155514121
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Official Citation:Warmann, E. C. and Atwater, H. A. (2016), Energy production advantage of independent subcell connection for multijunction photovoltaics. Energy Sci Eng, 4: 235–244. doi:10.1002/ese3.125
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:71729
Deposited By: Tony Diaz
Deposited On:03 Nov 2016 23:20
Last Modified:11 Nov 2021 04:50

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