Wafer integrated micro‐scale concentrating photovoltaics

Journal Article · Mon Jul 23 00:00:00 EDT 2018 · Progress in Photovoltaics

DOI:https://doi.org/10.1002/pip.3034· OSTI ID:1464554

Li, Duanhui ^[1]; Li, Lan ^[1]; Jared, Bradley ^[2]; Keeler, Gordon ^[2]; Miller, Bill ^[2]; Wood, Michael ^[2]; Hains, Christopher ^[2]; Sweatt, William ^[2]; Paap, Scott ^[2]; Saavedra, Michael ^[2]; Alford, Charles ^[2]; Mudrick, John ^[2]; Das, Ujjwal ^[3]; Hegedus, Steve ^[3]; Tauke‐Pedretti, Anna ^[2]; Hu, Juejun ^[1]; Gu, Tian  ^[1]

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1. Massachusetts Institute for Technology Cambridge MA USA
2. Sandia National Laboratories Albuquerque NM USA
3. Institute of Energy Conversion University of Delaware Newark DE USA

Abstract A novel micro‐scale photovoltaic concept, Wafer Integrated Micro‐scale Photovoltaics (WPV), is proposed, analyzed, and experimentally demonstrated. The WPV concept seamlessly integrates multijunction micro‐cells with a multi‐functional silicon platform that simultaneously provides optical concentration, hybrid PV/CPV architecture, and mechanical alignment features. Fabrication and optical performance characterization of the Si platform are described in this paper. Over 100% improvement in the concentration‐acceptance‐angle product ( CAP ) is demonstrated using the wafer‐embedded micro‐concentrating elements, leading to significantly reduced module material and fabrication costs, sufficient angular tolerance for low‐cost trackers, and an ultra‐compact optical architecture compatible with commercial flat panel infrastructures. The development of a prototypical module with a 400× concentration ratio is described. Outdoor optical characterization of the module shows acceptance angles of ±1.7° and ±2.5° for 90% of on‐axis power and full‐width‐half‐maximum, respectively. The projected performance of the PV/CPV hybrid architecture illustrates its potential for cost‐effective collection of both direct and diffuse sunlight, thereby extending the geographic and market domains for cost‐effective PV system deployment. Leveraging low‐cost micro‐fabrication and high‐level integration techniques, the WPV approach presents a promising route to combine the high performance of multijunction solar cells and the low costs of flat‐plate Si PV systems.

• Sponsoring Organization: USDOE
• OSTI ID: 1464554
• Journal Information: Progress in Photovoltaics, Journal Name: Progress in Photovoltaics Vol. 26 Journal Issue: 8; ISSN 1062-7995
• Publisher: Wiley Blackwell (John Wiley & Sons)
• Country of Publication: United Kingdom
• Language: English