Indirect energy flow between industrial sectors in China: A complex network approach

• Indirect energy flow networks based on input–output tables are constructed.
• Indirect energy flow networks display small world nature.
• Explore three types of centralities of sectors and identify key sectors.
• Key flow paths in the network are identified.
• Related policy implications are discussed.

Indirect energy consumption accounts for a large proportion of the all energy used in processes to make the final products and thus exerts huge pressure on environment. Structural analysis of indirect energy flow network is a prerequisite for solutions to energy related problems. The aim of this study is to reveal the structure of indirect energy flow network and its change from 1993 to 2007. To this end, we constructed three directed weighted IEFNs (indirect energy flow networks) with 28 sectors on the basis of three basic input–output tables from 1997, 2002, and 2007. By analyzing the clustering coefficient and the average path length of the networks, we obtained the small world nature of IEFNs. In the same study, we identified key sectors of the IEFNs on the basis of three centrality indicators from complex network theory, namely degree centrality, eigenvector centrality, and betweenness centrality. In addition, we analyzed the indirect energy flow paths in the network. Based on the knowledge of the structure of IEFNs and its trend, we discussed the possible policy implications.