Consistent or inconsistent? : the club convergence effect and matching degree analysis on energy consumption intensity and production density : evidence from the data of 2000-2020 in China

Clarifying the regional differences in coal production and consumption is important for the adjustment of the energy structure. To understand the spatial and temporal variability of coal production and consumption, this study examined coal consumption and production across 30 Chinese provinces over the period of 2000-2020 using the methodology introduced by Phillips and Sul. Then, we used the kernel density estimation method to analyze the dynamic changes. Finally, the Gini coefficient and coefficient of variation methods were used to quantify the unevenness in the production and consumption of coal. The analytical results strongly support the existence of convergence clubs. We find five convergent clubs for coal consumption and six convergent clubs for coal production. There are significant differences in the geographic distribution of convergence clubs for coal consumption and coal production. In addition, the difference in coal consumption levels between provinces widened, while the difference in coal production narrowed during the study period. The unevenness of the regional distribution and matching of coal production and consumption increased. Overall, the regional unevenness of coal production and consumption should be given sufficient attention. This study provides a reference on how to differentiate and adjust the production and consumption of coal in each region.