| Title |
A Study of Thermal Storage Assisted Heat Pump Utilizing Waste Heat from Building Complex |
| Abstract |
Field monitored performance data of a thermal storage assisted heat pump to recycle heat from building waste water is discussed in this paper. The heat pump system was designed for year-round domestic water (DHW) heating and summer time space cooling. In the DHW heating mode, the system consists of a waste heat recovery tank (220m3), a hot water storage tank (80m3), and the heat pump; and in the cooling mode, the same waste heat recovery tank as cool storage, an air-cooled cooling tower, and the same heat pump with a nominal cooling capacity of 531MJ/hr, at 0c evaporation and 40c condensing, The daily average summer time cooling COPs ranged 2.51-3.0. Including the hot water output for the domestic hot water, the combined COP ranged 5.5-6.2. During the winter time, the useful output from the system is hot water only. In this mode of operation, the DHW heating COPs ranged 2.94-3.12. The measured COPs were compared to the predictions from simulation by TRNSYS. The measured COPs were slightly lower than the predictions of TRNSYS. This project demonstrated technical feasibility of year-round recovery of heat from the waste warm water on top of the space cooling operation during the summer time. |