Dynamic changes in the energy–carbon performance of Chinese transportation sector: a meta-frontier non-radial directional distance function approach

The transportation sector is the main energy consumer and carbon emitter in China. To accurately evaluate the dynamic changes in the energy–carbon performance of the sector and to propose alternatives for sustainable development, this paper proposes an approach incorporating the meta-frontier method, global benchmark technology, and non-radial directional distance function. Using this approach, the paper proposes a new definition, named the global meta-frontier non-radial Malmquist energy–carbon performance index (GMNMECPI). GMNMECPI can be decomposed into technical efficiency change (EC), best-practice gap change (BPC), and technology gap change (TGC). This new method was then used to estimate the dynamic changes of energy–carbon performance in China’s transportation sector from 2006 to 2015. The paper also identifies the effect of current policies. The empirical results show that the energy–carbon performance of China’s transportation sector decreased annually by 1.636% during the study period. This reduction was mainly caused by a significant technology lag in the central area while primarily influenced by deterioration in efficiency in both the east and west. There is a distinct heterogeneity in technology across China’s three areas. Based on the findings, the paper closes with policy implications.