The Temperature Dependence Coefficients of Amorphous Silicon and Crystalline Photovoltaic Modules Using Malaysian Field Test Investigation

The temperature dependence coefficients of amorphous silicon and crystalline photovoltaic (PV) modules using Malaysian field data have been obtained using linear regression technique. This is achieved by studying three test stand-alone PV-battery systems using 62 Wp a-Si, 225 Wp multi-crystalline and 225 Wp mono-crystalline PV modules. These systems were designed to provide electricity for rural domestic loads at 200 W, 500 W and 530 W respectively. The systems were installed in the field with data monitored using data loggers. Upon analysis, the study found that the normalized power output per operating array temperature for the amorphous silicon modules, multi-crystalline modules and mono-crystalline modules were: +0.037 per°C, +0.0225 per °C and +0.0263 per °C respectively. In addition, at a solar irradiance value of 500 Wm-2, the current, voltage, power and efficiency dependence coefficients on operating array temperatures obtained from linear regression were: +37.0 mA per °C, -31.8 mV per °C, -0.1036 W per °C and -0.0214% per °C, for the a-Si modules, +22.5 mA per °C, -39.4 mV per °C, -0.2525 W per °C, -0.072 % per °C for the multi-crystalline modules and +26.3 mA per °C, -32.6 mV per °C, -0.1742 W per °C, -0.0523 % per °C for the mono-crystalline modules. These findings have a direct impact on all systems design and sizing in similar climate regions. It is thus recommended that the design and sizing of PV systems in the hot and humid climate regions of the globe give due address to these findings.