Programm Photovoltaik Ausgabe 2009 ... - Bundesamt für Energie BFE

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The short-circuit currents of the side attached crystalline Si-cells were monitored during the 275 hours
of irradition in the simulated sunlight of the SolarTest-65 lamp fitted with the "A-bulb" giving a light very
close to the natural sun (class A simulator).
Graph 10: Short-circuit current in function
of the elapsed time in the SolarTest-65
lamp (A-bulb) exposure of the side
attached crystalline Si solar cell, measured
in the CDM-1000 solar simulator set at
1000 W/m 2 light intensity.
From these short-circuit currents, it seems that most of the QD-FPC's showed a good stability over
this first period in the artificial sunlight.
The UV-VIS spectra of these QD-FPC show mostly a reduction in absorption, although some samples
are practically constant during the 275 hours arificial sunlight test, corresponding to ¼ year outside.
Graph 11: UV-VIS spectra of the QD-FPC
samples followed over time during the
SolarTest-65 artificial sunlight (950 W/m 2 )
exposure.
Most of the QD-FPC show only marginal decrease in absorption, especially in the 600-650 nm region,
after this rather short artificial sunlight test.
Conclusions of the final FPC stability assessment report:
1. The 470 nm blue high intensity LED light soaking test revealed that the Red305 dye seems
not to degrade significantly when compared to the dyes Yellow83, Yellow83 and CRS040, showing
each a manifest loss of absorption in the UV-VIS spectrum.
2. The SolarTest-65 artificial sunlight test at 1000 W/m 2 intensity showed that the short-circuit
current of the FPC side attached Si-cell is practically constant over an irradiation time of 400 hours, a
light exposure equivalent of about 1 /2 year outside. An other test in similar conditions stretching over
1300 hours showed that the degradation is less than 6 %, this corresponds to an exterior exposure
equivalent to 1.3 years.
3. The outdoors test at the FhG-IAP running over a period of 109 weeks, i.e. ~2 years, showed
only a small loss of ~5 % of relative absorption in the FPC composed of Red305 dye dissolved in a
PMMA matrix carefully polymerized from distilled MMA monomer. Moreover the spectral response
(quantum efficiency) of the Red305 in purified PMMA shows only marginal changes (~5 % loss) over a
period of 25 weeks outside.
FULLSPECTRUM, T. Meyer, Solaronix
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