Carbon mitigation potential and economic benefits of biomass co-firing in coal-fired power plants: A case study in Nanjing, China

As a critical region marked by high energy consumption and notable carbon output, the decarbonization of the power sector in the Yangtze River Delta region is crucial for advancing China's ambitious “dual carbon” targets. This study conducts a detailed life cycle assessment to scrutinize the effectiveness and challenges associated with the implementation of biomass co-firing and monoethanolamine-based carbon capture technologies, virtually implemented at an operational coal-fired power plant in Nanjing, a significant carbon-emitting city in China's Yangtze River Delta. Four configurations have been established to assess the environmental and economic benefits of these power generation systems, under both current conditions and with selected decarburization technologies. Our findings reveal that co-firing biomass at levels of 5–20 % yields a reduction in emissions of 31–151 kg CO2/MWh, when combined with carbon capture, 20 % biomass co-firing attains net negative emissions of 38–69 kg CO2/MWh. The integration, while environmentally beneficial, escalates generation costs by 5.4–97.3 % due to biomass pricing and carbon capture retrofit expenses, presenting an economic challenge. The findings of this study can offer policymakers comprehensive compass to formulate evidence-based policies aimed at promoting the low-carbon transition of the power sector in the region.