Thermodynamic Efficiency of Heat Pump Heating Scheme Using Ground and Sewage Heat

Abstract

Background. Currently, the development and research of thermodynamic or energy efficiency of combined heat pump heat supply systems with the use of several low-temperature sources of energy becomes relevant. Objective. The aim of the paper is to determine the dependence of the relative productivity of the vertical ground heat exchanger on the hot water heat consumption by the building and the ambient temperature. Methods. A thermodynamic analysis of scheme was carried out, on the basis of which conclusions were made on improving the working conditions of combined heat pump heat supply system and reducing the specific energy consumption for heat generation in the heating system. Results. The correlation for determining the total specific energy expenditure for the heat pump system with the use of ground and sewage heat is obtained. It is shown that the heat pump heating system scheme with the use of additional sewage heat is more effective than the initial heating scheme. The effectiveness depends on the consumption of hot water in the building, and the ambient temperature. Conclusions. It is determined that using this scheme in designing the heat pump heating system can significantly reduce capital and operating costs. The use of obtained dependencies in the development of heat pump systems will ensure the maximum energy efficiency of their operation.