Influence of the temperature on the intrinsic parameters of thin-film photovoltaic modules

The electrical parameters, the ideality diode factor and the parasitic resistances of a photovoltaic module can be estimated from its current–voltage ( I–V ) curve. However, there are only very few studies focused on thin–film devices, that could have a thermal behavior different from crystalline silicon technologies. This study analyzes the variation of these parameters from a set of current–voltage curves of several commercial modules from different technologies: single–crystalline silicon (sc–Si), multi–crystalline silicon (mc–Si), amorphous silicon (a–Si), tandem of micro–crystalline silicon and amorphous silicon (a–Si/ μ c–Si), tandem of cadmium selenide and cadmium telluride (CdS/CdTe), and copper indium selenide (CIS). Most of the modules present a positive value for the current thermal coefficient ( α ), but the voltage and power temperature coefficients ( β and γ ) are negative in all the cases. With respect the series resistance ( R S ), it is significantly higher for the thin–film modules than for the crystalline silicon ones. Moreover, the thermal coefficient of the series resistance ( κ ) varies depending on the technology. Regarding the shunt resistance ( R S h ), it seems to be insensitive with respect the temperature for a small range. Finally, the diode ideality factor ( m ) seems to be constant for crystalline silicon whereas it depends on the temperature for thin–film. • Only a very few studies are focused on the evolution of the intrinsic parameters of thin–film devices. • This study analyzes the variation of these parameters from a set of I–V curves of several modules. • The thermal coefficient of the series resistance κ varies depending on the technology. • The shunt resistance seems to be insensitive with respect the temperature. • The diode ideality factor has a clear dependence on the cell temperature for thin-film technologies.