Abstract:

Objectives To accurately calculate the carbon emissions of coal-fired power plants, combined with the actual production conditions of such plants, a refined life cycle carbon emission accounting study is carried out using a “cradle-to-gate” approach. The proportion of carbon emissions in each stage and its sensitivity characteristics are analyzed. Methods Taking 4 typical 600 MW supercritical units as examples, a detailed calculation of the refined carbon emissions containing the entire stages of raw material acquisition, raw material transportation, power production, and waste disposal is based on the life cycle assessment method. Results The carbon emissions from upstream stages, like raw material acquisition and transportation, account for 9.4% of the total emissions, with coal mining contributing the largest share, accounting for 5.77% of the total emissions. If the energy consumption in the coal mining stage is reduced by 5% and 10%, the carbon emissions over the life cycle of each unit can be reduced by 0.289% and 0.577%, respectively. The adoption of carbon capture technology can reduce the power plant carbon emissions by 78.8% to 82.3% under different scenarios. Conclusions As the main part of carbon emissions in the whole process of power production, coal combustion can reduce the coal consumption of unit power generation/supply by changing the combustion mode, improving the boiler efficiency and reducing the loss. The overall carbon emissions could be effectively reduced by the adoption of carbon capture technology. Although carbon capture increases energy consumption to a certain extent, it achieves a high carbon capture rate. The use of high-efficiency and low-energy carbon capture technology is a key means to reduce the carbon emissions of power plants.

Key words: coal-fired power plants, carbon emission reduction accounting, life cycle assessment, CO₂ capture