A comparative analysis of China's regional energy and emission performance: Which is the better way to deal with undesirable outputs?

Measuring and improving the energy performance with considering emission constraints is an important issue for China's energy conservation, pollutant emissions reduction and environment protection. This study utilizesseveral data envelopment analysis (DEA) based models to evaluate the total-factor energy and emission performance of China's 30 regions within a joint production framework of considering desirable and undesirable outputs as well as separated energy and non-energy inputs. DEA window analysis is applied in this study to deal with cross-sectional and time-varying data, so as to measure the performance during the period of 2000-2009. Twotreatmentsfor undesirable outputs are combinedwith DEA models and the associated indicators for simplex energy performance and unified energy and emission performance measurement are proposed and compared. The evaluation results indicate that the treatment of undesirable outputs transformation is more appropriate for China's regional energy and emission performance evaluation because it has stronger discriminating power and can provide more reasonable evaluation results that characterize China's regions. The empirical result shows that east Chinahas the highest and the most balanced energy and emission performance. The energy and emission performance of Chinaremained stable during 2000-2003, decreased slightly during2004-2006, and hascontinuously increased since 2007.