In this article, we firstly analyzed the historical development trends, regional economies, population, urbanization and carbon emissions of the four major regions which are the East, the Middle, the North-east and the West, respectively. Then we compared China's environmental Kuznets curve both in home and abroad, found that the relationship between economic development and pollution emissions varies from regions and countries. We used the IPAT model to design 48 peak CO2 emission scenarios in order to get to more comprehensive depict of future development path of China's carbon emissions. Furthermore, we used a centralized DEA to evaluate the allocative efficiency of scenario-based CO2 emission paths. As a consequence, we found that maintaining relatively high GDP growth (around 6%), reducing energy intensity by about 75% of average annual decline rate(around 4%); and increasing non-fossil energy to 21% to meet the Innovation plan of energy technology revolution 2016-2030 requirements is the most efficient low-carbon behaviors towards 2030 peak CO2 emissions of 10.57Gt. We also found that China can potentially reduce CO2 emission intensity (CEI) by up to 72.7% compared to the 2005 level in 2030, and therefore that official CEI reduction targets (60-65%) are well within reach. It is also found that in the future path of the predicted optimal scenario, only economic scale and low carbon per unit output value have a great contribution to the changes in carbon dioxide emissions.