Photovoltaic thermal heat pump system has gained much popularity in the recent research field, which generally refers to the integration of photovoltaic and solar assisted heat pump to meet the various building energy demand. In this paper, dual-use roll-bond photovoltaic thermal heat pump system employing new roll-bond photovoltaic thermal unit has been proposed and investigated experimentally. The system operation principles and the design method of the main components are introduced in more details. A mathematical model of each component of the system is developed according to distributed and lumped parameter models. The tri-generation performance evaluation method of the unit and system is also proposed. The experimental investigation on the tri-generation performance of the system is carried out simultaneously, in terms of the heating, cooling and power supply capacity. Through analysis, it is evident that the proposed system has the potential to provide space cooling, hot water, and electricity for buildings with high efficiency and long-term stable working condition. Furthermore, the detailed performance parameters analysis has been carried out. The results demonstrate that the roll-bond photovoltaic thermal heat pump system is practically feasible and has a large potential for building energy conservation.