Empirical procedure to correct concentrator cell efficiency measurement errors caused by unfiltered xenon flash solar simulators

Abstract

In this paper, we present an empirical error correction procedure for efficiency measurements of seriesconnected, multijunction concentrator solar cells. The error arises from the use of unfiltered xenon flash solar simulators with excess infrared radiation (wavelengths > 900 nm) into lowerbandgap subcells, and always results in an artificial increase of the measured efficiency. The efficacy of the procedure is demonstrated by comparing unfiltered efficiency data against other data from a flash simulator in which the spectral irradiance was properly adjusted.

Quadruple-Junction Inverted Metamorphic Concentrator Devices

“…At 1 sun, the device has a V oc of 3.445 V, a J sc of 12.49 mA/cm 2 , and an efficiency of 36.35%, as measured by the OSMSS. Notably, the T-HIPSS also provides data near 1-sun concentration, which agrees well with the OSMSS measurement due to the improved spectrum and measurement procedure [18]. At 327 suns, the efficiency peaks at (43.8 ± 2.2)% and the V oc is 4.10 V. The relative error of 5% is characteristic of the measurement and instrumentation.…”

“…This measurement technique reduces errors in the concentrator measurements due to the spectrum, which have been shown to result in erroneously high voltages, fill factors, and efficiencies [17]. Here, the first, second, and fourth junctions were filled correctly with < 1 % error, but the third subcell was overfilled by 30%; therefore, the correction procedure described in [18] was used. The 1-sun subcell J-Vs and luminescent coupling parameters were extracted using a spectrally adjustable solar simulator using a method described elsewhere [19].…”

Implications of Redesigned, High-Radiative-Efficiency GaInP Junctions on III-V Multijunction Concentrator Solar Cells

“…8 we show the performance of this 4J IMM under concentration. Spectrally-adjustable [29] flash measurements (T-HLPSS) are in good agreement with the spectrally-adjustable one-sun measurements (OSMSS) and with the V oc predicted from the sum of the EL measurements. This 4J IMM achieved an AMI .5 direct efficiency of 43.8% at 327 suns.…”

Solar water splitting by photovoltaic-electrolysis with a solar-to-hydrogen efficiency over 30%

“…2. Following a standard method for characterizing concentrated PV cells, we used the ratio of the short circuit currents to calculate that the cell was illuminated with 42 suns white light under the concentration condition (calculation details provided in Supplementary Note 1)3233. At the maximum power point, the cell voltage ( V MPP ) output is 2.91 V and the current density ( J MPP ) is 565.9 mA cm −2 .…”