Performance investigation of acetone and mobiltherm as a heat transfer medium in a hybrid photovoltaic-thermal system

Photovoltaic (PV) cells convert solar energy into electrical energy and the efficiency possesses a negative coefficient of 0.2-0.5%/degrees C beyond Standard Test Conditions (STC) of 25 degrees C. PV cells also called solar cells could attain an increase in 50-60 degrees C above STC, thereby reducing its efficiency. This research addresses the issue by utilizing the energy resulting from overheating of panels for the generation of hot water. This research deals with the simulation, modeling, and experimentation of hybrid photovoltaic-thermal (PV-T) system for the generation of electrical energy and hot water. The objective is uniform cooling of the panel, thereby resulting in enhancement of power along with the generation of hot water at 60 degrees C. The design was accommodated in a single integrated unit without any application of pumping devices. Hot water at 60 degrees C was obtained experimenting with two different heat transfer mediums. Acetone and mobiltherm were tested as the medium of heat transfer in this research. The simulation was carried out for the hybrid PV-T system to study the various parameters affecting the system along with an estimation of the discharge capacity of the system in real-time conditions. The discharge of water using acetone as heat transfer medium was 18.2 l and using mobiltherm was 23.4 l. The average electrical and thermal efficiency attained using acetone as heat transfer medium was 8.46% and 35.05%, whereas the average electrical and thermal efficiency using mobiltherm as heat transfer medium was 9.62% and 45.48%, respectively.