Performance analysis of central heating system combining urban heating network with geothermal energy

Presents a central heating system combining the urban heating network with geothermal energy. In the heating station of this system, the water-to-water heat exchanger is replaced by the absorption heat exchange unit, through which the heat is supplied to the user. The shallow geothermal energy is extracted by the heat pump, which is driven by the large heat transfer temperature difference between the primary and secondary network. Taking the new system as the study object, establishes the mathematical models of all parts, and then simulates and analyses the performance of the system. The results show that the COP of the absorption heat exchange unit is 1.25, and the heating capacity of the heating network is improved by 25% on condition that the central heat source is not expanded and the energy consumption does not increase, which could effectively alleviate the serious shortage situation of the northern central heating source. Compared with the conventional central heating system, the incremental investment of the system could be recovered in about 4.3 years. Therefore, the system has better economic effect and development prospect.