Part A) In the laboratory of this course, a concentrating photovoltaic and thermal solar panel has been tested, Fig. 1a). Each group of cells (series connected) indicated in the figure has a by-pass diode in parallel.Consider that the first and second group of solar cells (8 and 11 cells’ sets) were tested in series under uniform illumination, keeping the remaining solar cells without illumination. The voltage-current curve of this series is presented in Fig. 1b). From it, estimate the following parameters for one solar cell:

Question 1) What is the short-circuit current, Isc?
Isc= [A]

Question 2) What is the diode ideality factor, n.
n=

Question 3) What is the dark-saturation current, Is [uA].
Is= [uA]

Question 4) Two tests of 100% shading were implemented: 1) with shading in the first group of cells (8 cells) and 2) with shading in the second group of cells (11 cells). The curves obtained are shown in the next figure. Which curve corresponds to the 100% shading in the first group (8cells)?

 curve a).
 curve b).
 curve c).

Part B) An installer decides to use the 185W NU-185 (E1) solar panel, whose mechanical/electrical and characteristic curves are detailed in Figs. 1a and 1b, respectively. For items a) to f), determine the characteristics of the panel for an irradiance of 1000 W.m^–² and a panel temperature of 25°C.

Question 5) Calculate the maximum power delivered by the photovoltaic panel.
Pp= [W]

Question 6) Calculate the efficiency of the photovoltaic panel at maximum power.
eff= [%]

Question 7) Which value of Resistive load (R_eq) must be applied to the PV panel at the maximum power.
RL= [Ohm]

The photovoltaic system is sized to produce 9 kWp (the kilo-watt peak (kWp) is a unit of measurement of the power produced by a panel when the luminous flux is 1000 W.m²). The overall efficiency of the installation is estimated at η_g = 10% taking into account the efficiency of the panels but also the orientation of the cells, the electrical losses, etc.

Question 8) What total panels’ surface should be installed to produce 9 kWp?

Apv= [m^2]

Question 9) In a region where the solar irradiation is 1200 kWh/m²/year, what is the annual income of this installation in the case where the purchase price is 0.35€/kWh?

Income=  [€]