China’s coal power decarbonization via CO2 capture and storage and biomass co-firing: A LCA case study in Inner Mongolia

In this study, a membrane-based CO2 capture and storage (CCS) chain and a co-firing system of coal and biomass were virtually implemented in an existing coal power plant in Inner Mongolia. Three life cycle assessment (LCA) models were developed to evaluate the environmental performance of the power generation system under business-as-usual (BAU) conditions and with the implementation of the selected technologies. The CCS system reduced CO2 emissions from the power plant by about 90%, but significantly increased upstream emissions, limiting the LCA mitigation potential to 37%–48% of the 1.14 kg CO2/kWh estimated for the BAU scenario. Combining biomass co-firing with CCS achieved negative emissions from the power generation stage and reduced the total CO2 emitted under the LCA scope by 57%–67%. However, both technologies had negative impacts on the local environment, which were quantified by a range of indicators such as eutrophication potential (+13%–37%), toxicity for both aquatic (+12%–33%) and terrestrial (+35%–68%) ecosystems, and consumption of freshwater (+46%–61%). The major factors preventing a more significant mitigation of CO2 emissions and shifting the environmental burden to local ecosystems were the increased electricity and coal consumption for implementing CCS and the reliance on diesel and artificial fertilizers in the biomass supply chain.