An investigation on the heat transfer coefficient (HTC) of a heat pipe heat exchanger (HPHE) was carried out while being installed as a cooling mechanism on photovoltaic panels. The Ecohouse at the University of Technology and Applied Sciences in Muscat, Oman, was used as the case study. The experiment monitored the effect of temperature variations on PV-HPHE-induced power generation. The heat pipes were arranged in a double-sided condenser in a spanwise manner with spacing 50 mm in the center with an inclination angle of 3°. J-type thermocouples (exposed wire, polytetrafluoroethylene (PTFE) insulated) with a tip diameter of 1.5 mm were used. The results indicated mean values of HTC that were measured at 2.346$\mathrm{W}/{\mathrm{m}}^2 \mathrm{K}$. The findings showed that the HTC values possessed a minimal standard error from the effect of variations of the ambient temperature. The mean HTC value of 2.346 $\mathrm{W}/{\mathrm{m}}^2 \mathrm{K}$ can be used in the succeeding experiments using the same novel PV-HPHE setup. Additional results showed the recorded variations from the mean value of the HTC effect on the HPHE heat flow generation, which resulted in a 29% increase in power performance efficiency using PV-HPHE.

The uncertainty regarding the capacity of photovoltaics to generate adequate renewable power remains problematic due to very high temperatures in countries experiencing extreme climates. This study analyses the potential of heat pipes as a passive cooling mechanism for solar photovoltaic panels in the Ecohouse of the Higher Colleges of Technology, Oman, using computational fluid dynamics (CFD). A baseline model has been set-up comprised of 20 units, 20 mm diameter water-filled heat pipes, with a length of 992 mm attached to a photovoltaic panel measuring 1956 mm × 992 mm. Using the source temperature of 64.5 °C (337.65 K), the findings of this work have established that a temperature reduction in the range of up to 9 °C is achievable when integrating heat pipes into photovoltaic panels. An optimum spacing of 50 mm (2.5 times the diameter of the heat pipe) was determined through this work, which is also a proof-of-concept towards the use of heat pipe technology for passive cooling of photovoltaic panels in hot climates.