Greenhouse gas emissions caused by human activity has had a huge impact on ecology. If the climate change issue cannot be resolved effectively, there will be more than 100 million people will lost their lives by 2030 and global economic growth will be cut by 3.2%. Effective control and reduction of greenhouse gas emissions is urgent problems of humanity. Currently, China's total greenhouse gas emission is already beyond the United States as the world's biggest emitter of greenhouse gases. China's coal-fired power generation is one of China's major C02 emission sources, thus reducing greenhouse gas emissions is important in conveying coal-fired carbon emissions to reduce China's total carbon emissions. And the prerequisite to achieve coal-fired power plant carbon emissions reduction is to calculate the carbon emissions from coal-fired power plant carbon emissions trading accurately and feasibility of low carbon power plants economically. In this study, first, the carbon emissions calculation scope is defined according to the World Resources Institute calculation tools, second, discussion on why should power plants adopt different methods of calculation according to their industrial analysis's refinement degree of the coal. And finally, carbon emission calculation and comparative analysis are conducted for two groups of different unit types of thermal power plants in China. Based on the above analysis, it shows that compared to small capacity generators, the large capacity and high parameters coal-fired generators not only can improve the efficiency of energy use, but also can reduce C02 emissions resulting from the production of electricity. Second, in a coal-fired power plant, stationary combustion of coal accounts for an absolute proportion of C02 emissions, while desulfurization and purchased electricity account for smaller proportion, but the absolute amount of emissions is not that small. Again, when compared to smaller capacity generators, the large capacity and high parameter units consumed less coal in power production, and its C02 emission concentration is relatively high, thus it is more suitable for the carbon capture system installation, which aids in increasing the efficiency of capturing and in reducing cost of C02 capturing. Therefore, this study recommends that future carbon capture systems construction should prioritize large-capacity and high parameter unit. This study's innovation is that it considers a coal-fired power plant's coal quality, power plant's desulfurization and power purchasing factors, in accordance to power plants using different calculation methods in industrial analysis of coal, aiming for more precise calculation of a coal-fired power plant's carbon emission.