According to the Paris Agreement signed on 12 December 2015, forests have great impact on controlling CO₂ emissions. This study uses the nonoriented dynamic slack‐based data envelopment analysis model to evaluate the impact of a forestry area on the annual and overall energy efficiency in 28 EU countries during 2009‐2016. We found that annual and overall energy efficiency improved slightly and the energy efficiency in each country also changed when the forestry area was used as the output variable. Although the total energy consumption has declined slowly, CO₂ emissions have not declined effectively. Thus, it will be challenging for the EU to meet its target of cutting CO₂ emissions by 30% by 2030. All countries should take additional measures, such as energetically increasing forestry areas, optimally distributing the labor force among industries, and gradually replacing fossil fuels with renewable energy to improve their energy efficiency.

Since thermal power generation is still one of the main sources of carbon emissions in China, the economic benefits and productivity of the thermal power generation industry have been seriously affected in recent years with the increasingly strict environmental regulations and restrictions on carbon emissions, as well as by the sharp fluctuations of coal prices. Therefore, it has been an important issue to improve the productivity performance of the thermal power industry. Due to the regional heterogeneity among different regions of China, we introduced a meta-frontier framework into the energy cost productivity model to develop a meta-energy cost productivity model. The energy cost gap between the group-specific and meta-frontiers was also utilized to assess the convergence rate of the group-specific frontier to the meta-frontier. The estimated results present that the energy cost efficiency of the eastern region outperformed that of the other two regions, and the cost Malmquist (CM) productivity of these three regions all showed positive growth, in which the progress of allocative efficiency and price effect were the main driving factors. Additionally, the central and western regions displayed the convergence of group-specific CM productivity towards the meta-frontier.