Integrating metal hydrides in evacuated tube collectors for optimal solar energy management in a PV/T system

This study presents the design and simulation of an innovative Metal Hydride-Based Photovoltaic/Thermal Evacuated Tube Collector (MH-PV/T-ETC for short). The collector featuring five evacuated tubes, each equipped with photovoltaic cells and partially filled with metal hydride. The system investigates the capabilities of metal hydrides for thermal storage through thermochemical reactions. Its effectiveness is evaluated through a detailed numerical analysis using a 3D mathematical model. Two scenarios are examined in the simulation, the Scenario 1 includes continuous water flow during day and night. The Scenario 2 includes water flow occurs only at night, allowing the system to release the stored heat during the night. The results show that Scenario 2 yields 70.4% more thermal energy than Scenario 1. Moreover, Scenario 2 achieves a maximum water outlet temperature of 334.7 K with a thermal efficiency of 46.51%, whereas Scenario 1 reaches 326.6 K with a thermal efficiency of 27.3%.