This paper investigates the competition intensity of the energy flow among Chinese sectors by employing input‒output (I–O) analysis, a two-mode complex network and the resource allocation process (RAP). Specifically, there exists energy flow from the upstream sector to different downstream sectors, and there are competitive relationships among these different downstream sectors. Moreover, the total amount of energy consumption is constant, and the amount of energy required by each sector varies. Thus, the competition intensity among sectors also varies. The empirical results are as follows. First, the characteristics of energy flow and the competitive relationship have changed little, which means that the energy structure has almost not changed. Second, the same types of sectors have much closer links, indicating that the competition intensity in these sectors is much stronger. Third, there are two obvious features in the energy competition intensity of sectors: (1) Sectors that experience competition by others for energy are more than sectors that compete with others (2) The competition intensity among sectors and in industry as a whole gradually decrease from 2012 to 2020. This study helps provide insights by analyzing competition intensity and by providing suggestions for energy distribution. •Providing a new research perspective for studying energy flow.•Combining multiple methods to study the competition intensity of energy flow.•Sectors in the same type exhibit stronger competitive intensity.•Providing recommendations for policy makers in energy distribution.