Posted by Anonymous on .
Figure 1 shows a simplication of the AM1.5 solar spectrum at 1000W/m2. The spectrum is divided in three spectral ranges:
A for 0nm<λ<620nm
B for 620nm<λ<1240nm
C for 1240nm<λ<1860nm
The photon flux in each spectral range is also shown in the figure.
a) The hydrogenated silicon carbide material (aSiC:H) is a new type of amorphous semiconductor material which has been recently studied for PV applications. This material has a relative large band gap of 2.0 eV. Imagine we integrate this material in a singlejunction pin solar cell as shown in Figure 2a below. In which spectral ranges does this solar cell convert light into charge carriers?
1)A
2)B
3)C
b) What is the Jsc (in mA/cm2) of the solar cell if only 65% of the absorbed photons result in a current?
c) The Voc in V of the aSiC:H solar cell can be roughly estimated by the equation:
Voc=Egap(J)2q=Egap(eV)2
where q is the elementary charge, Egap(J) is the bandgap energy expressed in Joules, and Egap(eV) is the bandgap energy expressed in eV. The fill factor of the solar cell is FF=0.80. What is the efficiency of the solar cell (in %) ?
An upconvertor is a material which can convert two lowenergy photons into a higher energy photon. Placing an upconvertor in our solar cell can help to reduce the spectral mismatch, since it can convert some photons with energy lower than 2 eV, which are not absorbed by the aSiC:H cell, into a photon with an energy higher than 2 eV. Figure 2b depicts this possibility.
d) In the upconvertor 1, two photons are converted into one photon with 100% conversion efficiency. If all photons with energy above that of the band gap of aSiC:H are absorbed in the aSiC:H layer, in which spectral range can the photons be upconverted so that they contribute to the current in the cell as well?
1)A
2)B
3)C
e) In that case what would be the shortcircuit current density and the efficiency of the solar cell illustrated in Figure 2b? Assume again that 65% of the absorbed photons result in a current.
Shortcircuit current density in mA/cm2
Efficiency in %
f) In upconvertor 2 (see Figure 2c), three photons are converted into one photon with 100% conversion efficiency. if all photons with energy above that of the band gap of aSiC:H are absorbed in the pin cell, and convertor 1 absorbs only the photons in the spectral range as considered in parts e) and f), in which spectral part can the photons be upconverted by convertor 2 so that they contribute to the current in the cell as well?
1)A
2)B
3)C
g) In that case what would be the shortcircuit current density and the efficiency of the solar cell illustrated in Figure 2c? Assume that 65% of the absorbed photons result in a current.
Shortcircuit current density in mA/cm2
Efficiency in %

Solar Energy Please Help 
I.G.,
a) A
d) B
f) C 
Solar Energy Please Help 
Anonymous,
Can you also give out the rest of the answers?? thanks

Solar Energy Please Help 
jen,
where is the rest of the answers?

Solar Energy Please Help 
Anonymous,
jen the answers are in your nose.
Next time ask nicely. 
Solar Energy Please Help 
Ken,
It is not possible to solve the rest of the answers the figure are missing.

Solar Energy Please Help 
Anonymous,
Please Is anybody who can help this question? Thanks

Solar Energy Please Help 
Ken,
Why don't you add the missing figures
2a, 2b, and 2c 
Solar Energy Please Help 
A,
courses edx org/c4x/DelftX/ET3034TUx/asset/Week5_Specturm png
This is the image's url, replace the spaces with dots 
Solar Energy Please Help 
Ken,
Link doesn't works

Solar Energy Please Help 
A,
postimg org/image/kylqxalt7/
Try this put a dot after 'postimg' 
Solar Energy Please Help 
Anonymous,
The link is for fig. 1
still need fig 2a, 2b, and 2c 
Solar Energy Please Help 
Anonymous,
ϕ=9.3∗1020m−2s−1 for 300nm<λ<650nm
ϕ=8.4∗1020m−2s−1 for 650nm<λ<850nm
ϕ=1.4∗1021m−2s−1 for 850nm<λ<1250nm 
Solar Energy Please Help 
Anonymous,
AND
Voc = Egap(J)/2q = Egap(eV)/2 
Solar Energy Please Help 
Anonymous,
Sorry the above 2 answers are for another question...

Solar Energy Please Help 
Anonymous,
use this link
postimg org/image/htap77x5d/ 
Solar Energy Please Help 
Ken,
1a. = A
1.b = 10.4mA/cm2, 8.33%
1c = B
1d = 18mA/cm2, 14%
1f = C
1g = 18.7 mA/cm2, 15% 
Solar Energy Please Help 
Anonymous,
Thanks

Solar Energy Please Help 
Anonymous,
Can you please answer this too
jiskha com/display.cgi?id=1382813246 
Solar Energy Please Help 
UNO,
Thanks Ken

Solar Energy Please Help 
Lauren,
what are the answer to the e) please

Solar Energy Please Help 
Naif,
e 14 and thanks for the answers guys i will pray for u :)

Solar Energy Please Help 
student,
e is 14 and 14 again

Solar Energy Please Help 
MANIRAGUHA Eric,
1)A
2)10 mA/cm^2
3)8%
4)B
5)18mA/cm^2
6)14%
7)C
8)19mA/cm^2
9)15%
Enjoy guys!!!! 
Solar Energy Please Help 
SB,
When adding the photon flux of A and half of the photon flux of B I come to 1.55E+17 photons/cm2. This gives a shortcircuit current density of 16.12mA/cm2 which is wrong. Where is my mistake???