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The building envelope is of great significance for building thermal comfort, and photovoltaic heat (PV/T) can be effectively utilized through phase change heat storage technology to reduce heating energy consumption. In this paper, a phase change heat storage structure with subzone rotation is proposed for the building envelope. A numerical model of a triplex-tube LHTES unit is established by using the enthalpy-porosity method and verified by experimental data. The study employs the Taguchi method to select rotation speed in different regions and fin/tube wall material as variables. The effects of different variables on heat release rate and solidification time are investigated, and the interaction of each parameter on solidification performance is analyzed through signal-to-noise ratio. The findings indicate that when the inner and outer tube speeds are 0.3 rpm and 0.5 rpm, respectively, compared to the initial model where both inner and outer tube speeds are 0.1 rpm, the average temperature response rate and the average heat release rate are increased by 51.47% and 61.04%, respectively. Meanwhile, the solidification time is shortened by 40.49%. However, the release of the total heat is reduced by 0.66%. The study concludes that increasing rotation speed or solidification consistency of PCM in different areas is of great value in enhancing overall solidification performance. Finally, the specific effect of increasing regional rotation speed on the solidification process is studied through temperature/flow rate monitoring in the unit.