Implementing suitable operation strategies significantly enhances the overall performance of the energy network of solar buildings. Previous studies predominantly concentrated on dispatching energy from standalone photovoltaic or photothermal modules within buildings. The photovoltaic/thermal (PV/T) modules have garnered attention due to their higher energy efficiency. However, the investigations targeting the operation strategies of PV/T modules in building remain scarce. To fill this research gap, this study scrutinized the maximum self-consumption (MSC), time-of-use (TOU), and optimization-based (OPT) strategies within a building energy system integrated with PV/T modules. The investigation encompassed an analysis of overall performance, parameter sensitivity, and optimal energy storage capacity. The main results were: (1) The OPT strategy displayed superior flexibility and lower operation costs compared to other strategies but exhibited lower energy utilization efficiency and greater grid impact. (2) The MSC strategy demonstrated lower sensitivity concerning battery power and charge states when contrasted with other strategies. (3) The optimal capacities for battery and water tank configurations for the MSC, TOU, and OPT strategies were identified as 4 kWh/200 L, 2.5 kWh/200 L, and 4.5 kWh/100 L, respectively. This research aims to provide reference and insights for planning the integration of PV/T modules into building energy systems.