Energy saving potential of pipe-embedded building envelope utilizing low-temperature hot water in the heating season
Abstract An active pipe-embedded building envelope has been verified to be effective for reducing heat transfer through building envelopes in summer. To decrease the energy consumption of heating, air source heat pumps are proposed for generating low-temperature hot water for the pipe-embedded building envelope in this study. A comprehensive numerical model is adopted to simulate the dynamic heat transfer in the pipe-embedded structure, and the model has been validated by experiment. The energy consumption and operation cost of the novel system are analyzed for different water temperatures. The seasonal performance in different cities and orientations is evaluated in winter conditions. The results show that 84% of the heat transfer on the internal surface can be reduced, whereas the heat dissipation on the external surface is increased by only 18% in Beijing. The proposed system is more suitable for cold regions because more heat transfer can be reduced there. The reduction ratios of the pipe-embedded system are close for all of the orientations, but the reduction amount on the north is 40% more than that on the south. The water temperature has a significant impact on the performance of the system, and room temperature water is suggested. Overall, the proposed system is effective as an auxiliary heating system.