Operating control modes of a hybrid groundsource heat pump system

Aiming at popularly used groundsource heat pump systems, presents three operating control modes and establishes an evaluation method based on the cylindrical source theory. Simulated results show that there exists an optimization problem between the underground thermal balance and running time of cooling towers. From the viewpoint of energy efficiency of cooling towers and underground thermal balance, recommends the operating mode by setting the average water temperature of buried exchangers or by setting the difference between the water temperature of buried exchangers and the wetbulb temperature of environment. The operating modes of the hybrid systems shall be determined based on the integration of different factors and the proper combination of the three modes is also allowed if necessary.