Integrated optimization study of hot water supply system with multi-heat-source for the public bath based on PVT heat pump and water source heat pump

Abstract

The public bath is the emphasis target of energy-saving renovation of existing public buildings in China. In that case, the integration of the hot water supply system according to the characteristics of heat sources should be studied and optimized to improve the comprehensive energy efficiency and the hot water production of the system. This paper analyzed and remedied the deficiencies of several common hot water supply systems with multi-heat-source, introduced a novel hot water supply system with multi-heat-source based on PVT (photovoltaic and thermal) heat pump and water source heat pump, and then carried out the integrated optimization research of this new system. The main studies include: (1) Established the novel hot water supply system with multi-heat-source and the calculation model of system heating characteristic. (2) Introduced the evaluation method of the comprehensive energy efficiency and economic performance for the hot water supply system with multi-heat-source. (3) Aiming at reducing the total cost of hot water supplying, the integration optimization ideas of system were proposed. By above methods, the integrated optimization of the existing North Mountain Public Bath in Dalian University of Technology was conducted. On one hand the daily production of the existing hot water supply system in the public bath is increased from 80 t to 146 t, the supply capacity of hot water is significantly promoted. On the other the total cost of hot water supplying decreases from 9.6 RMB/(t year) to 4.9 RMB/(t year), the comprehensive energy efficiency and the economic performance of system is improved.