Characteristics of InGaN-based concentrator solar cells operating under 150X solar concentration.

Institute of Electro-Optical Science & Engineering and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan City 70101, Taiwan.
Optics Express (Impact Factor: 3.55). 07/2011; 19 Suppl 4:A695-700. DOI: 10.1364/OE.19.00A695
Source: PubMed

ABSTRACT InGaN/sapphire-based photovoltaic (PV) cells with blue-band GaN/InGaN multiple-quantum-well absorption layers grown on patterned sapphire substrates were characterized under high concentrations up to 150-sun AM1.5G testing conditions. When the concentration ratio increased from 1 to 150 suns, the open-circuit voltage of the PV cells increased from 2.28 to 2.50 V. The peak power conversion efficiency (PCE) occurred at the 100-sun conditions, where the PV cells maintained the fill factor as high as 0.70 and exhibited a PCE of 2.23%. The results showed great potential of InGaN alloys for future high concentration photovoltaic applications.

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