This preview shows pages 1–2. Sign up to view the full content.
University of Delaware
Department of Electrical and Computer Engineering
ELEG620: Solar Electric Systems
Homework #3
Solar Cells
1.
Consider the cutaway of a textured pyramid surface shown below. For a given
wavelength of light the fraction of reflected light is given by R.
a)
Find an expression for the total reflectivity of the light incident on the textured
surface, in terms of both R and
α
, the angle of the pyramid side relative to a flat
surface that is normal to the incident light. You can stop increasing the angle
when 100% of incident light bounces three times.
b)
Given that the side of the pyramid is created in a (001) surface by exposing (111)
planes, what is the angle
α
?
c)
If the reflection is 20% at a particular wavelength then compute the reflectivity of
the textured surface (use the angle from b))
2.
a) A silicon solar cell (band gap 1.12 eV) is uniformly illuminated by monochromatic
light of wavelength 800 nm and intensity 20mW/cm
2
. Given that the quantum
efficiency at this wavelength is 0.80 find the short circuit current if the area of the cell
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview. Sign up
to
access the rest of the document.
 Fall '08
 Honsberg,C

Click to edit the document details