A numerical and experimental study of micro-channel heat pipe solar photovoltaics thermal system

A novel micro-channel heat pipe array incorporated with crystalline silicon (c-Si) solar photovoltaic/thermal system (MHP-PV/T) was designed and constructed by the authors. The proposed design configuration combined c-Si solar cells and wide micro-channel heat pipes (MHP) that were filled with prescribed amount of acetone as refrigerant under a vacuum condition in the same insulated frame to simultaneously provide electrical and thermal energy. Heat and mass transfer characteristics of the MHP-PV/T were preliminary investigated using both numerical and experimental methods. The transient behavior and parametric heat transfer limitations of the heat pipe were also examined using MATLAB. A linear relation between the thermal instantaneous efficiency ηth and the reduced temperature parameter (Tout-Tin)GT-1 was established. The maximum instantaneous efficiency was found to be 54.0% with an electrical power output of 70 W. The results indicated that the daily thermal and electrical efficiencies were 50.7% and 7.6%, respectively. The transient behavior of the MHP shows a faster thermal response to heat input within the temperature range of 48.8–49.2 °C and slower response when the thermal diffusivity was reduced to 0.05 cm2/s. The results also reveal good agreements between model simulation and experimental measurement with sufficient confidence.