Modelling and experimental analysis of a seasonally tracked V-trough PV/T system in India

Abstract

Hybrid PV/Thermal (PV/T) systems can generate both electrical and thermal energy simultaneously. These systems are already finding interesting applications in the fields of desalination, sensible heating/cooling and other allied industrial processes. An effective way to further improve the overall system efficiency is by using V-Trough’s to concentrate incoming sunlight and enhance the power output from these systems. In this work, we study the performance of a V-Trough PV/T system connected to a reverse osmosis plant in India. A coupled optical, electrical, and thermal model is presented and validated by experiments. The optical analysis was carried out while including the variations in suns altitude and zenith angle over the day. The impact of the variable inlet water temperature with time is included in the model. The performance of a V-Trough PV/T system is compared with a standard PV system. An average increase of 35% was observed in the electrical power output from the V-Trough PV/T system as compared to the conventional one, with the maximum being 63%. Using the water circulation, an average of 778 BTU/m2 of thermal energy was extracted from the V-Trough PV/T system. A maximum temperature difference of 5.2 °C was observed in the feed water at the system outlet, this accounted for a maximum 1/3rd of the total energy recovery when using the V-Trough PV/T system. Feeding heated water to the RO unit in the PV-RO system helped in significantly increasing the quantity and quality of the permeate obtained from the system. A parametric study of the effect of varying mass flow rate on the performance of the system is also discussed.