China's Energy Efficiency: Re-estimation Incorporating Human Capital and the Analysis of Its Distribution Dynamics

摘要

Energy conservation and carbon emission reduction have recently been important issues for China's low-carbon development. Almost all previous studies on energy efficiency evaluation have focused on the number of employees as the labor input but ignored the qualitative information about laborers, which may induce a biased evaluation. In the present paper, we utilize an SBM model to re-estimate the energy efficiency with CO2 emissions of China's 29 provinces from 2003 to 2011 with a modified labor input-human capital stock. A comparative analysis is first presented to distinguish between energy performance indicators with a traditional labor input (the number of employees), TEPI, and with a modified labor input (human capital stock), MEPI. The efficiency evaluation with the number of employees as the labor input underestimates energy efficiency. The evaluation results indicate that there was a declining trend of energy efficiency with CO2 emissions in China. The eastern area performed the best, and the western area had the worst performance. In addition, the kernel density estimation of MEPI showed that the distribution curves had a left shift overall and in the three regions, which reveals worsening energy efficiency performance in the sample years, and the efficiency distribution displayed differently in the three regions.