Effective Design and Operation of Large-scale Hybrid Ground Source Heat Pump System: A Case Study of Hubei Province library

Abstract

Hybrid ground source heat pump system (HGHPS) has the advantages of energy saving, environmental protection, low carbon. A HGHPS can meet a portion of the peak heating or cooling load by the use of auxiliary equipment (such as a cooling tower or a boiler), which can provide a stable, sustainable and sufficient source for cooling and heating in buildings. All of these can dramatically decrease the initial investment of ground source heat pump systems. So the application of HGHPS in hot summer and cold winter area is becoming more and more widely. However, the added complexity of hybridizing a ground source heat pump system in large buildings brings technical challenges in design and operation stage, which slows down the technology development to a certain extent.
In this paper, a HGHPS in a large public building named Hubei Province library in China's Wuhan is taken as an example. Considering the effect of the peak to valley difference of air conditioning load demands on the heat transfer characteristics of large-scale buried pipe groups, the design measures and operation strategies of a large-scale HGHPS are analyzed. Compared with the monitoring data after operating, the impact on system energy efficiency, economy and environment are discussed to demonstrate the effectiveness of the HGHPs. Further improvement measures are proposed based on the design and operation experience, which can help to achieve the reliable utilization of HGHPS in buildings.