D
diffusion coefficient, m
2 s
−1
E
energy, J
f
Fermi-Dirac distribution, −
F, F
force, N
FF
fill factor, −
G
generation rate, m
−3 s
−1
g
density of states function, m
−3 J
−1
G M
irradiance on a PV module, Wm
−2
I
current, A
I e
irradiance, Wm
−2
J, J
current density, Am
−2
k
wave number, m
−1
ℓ n , ℓ p
width of space charge region, m
L
diffusion length, m
L e
radiance, Wm
−2
sr
−1
m
mass, kg
m*
effective mass, kg
M e
radiant emittance, Wm
−2
sr
−1
N
particle density, m
−3
n
electron concentration, m
−3
n
refractive index (real part), −
P
power, W
p
hole concentration, m
−3
Q
heat, J