Integrating bibliometrics and roadmapping: A case of strategic promotion for the ground source heat pump in China

The ground source heat pump (GSHP) is one of the most promising energy-efficient technologies in development. However, the degree to which the application of GSHP has been promoted in China remains unsatisfactory. Critics of GSHP development in China have asserted that a more thorough understanding of GSHP is paramount for technology road mapping. This, in turn, has affected policymakers׳ development of regulations that facilitate R&D related to GSHP. Because many researchers have proposed specific terms and categorization approaches in relation to GSHP, it is imperative to transform and analyze a substantive knowledge system derived from massive amounts of qualitative information to produce a roadmap for the development of GSHP. To this end, we employed a bibiliometrics approach to analyze patent information. First, we engaged in semantic labeling of patent files and recorded the co-occurrence of the terms associated with the GSHP׳s ontology. Second, we employed an algorithm called the Fuzzy Overlapping Cluster (FOPC) to analyze the co-occurrence information. In doing so, we sought to classify patent data and further define sub-technologies associated with GSHP. Third, we used accumulative patent numbers to develop a logistic model for observing development trends related to each GHSP sub-technology. Fourth, we leveraged social network analysis to calculate and graphically illustrate interdependence among GSHP sub-technologies. The results these analytic approaches produce allowed us to conclude that (a) GSHP should be categorized into four sub-technologies: the water source heat pump, the ground coupled heat pump, the heat pump/system operation technique, and central air-conditioning system, and (b) the government should revise building codes and standards with a consideration of GCHP, as well as the heat pump/system operation techniques.