Life cycle greenhouse gas emissions assessment: converting an early retirement coal-fired power plant to a biomass power plant

Decommissioning aging coal-fired power plants (CFPPs) represents an effective strategy for reducing greenhouse gas (GHG) emissions, accelerating energy mix diversification, and achieving nationally determined contributions and net-zero emissions targets. However, dismantling the CFPP and building a renewable energy-based power plant with a capacity equal to a dismantled CFPP could burden state finances. Therefore, converting coal to 100% biomass fuel in the aging CFPP is one of the proposals that needs to be studied. This study conducted an environmental assessment concerning the Life Cycle Greenhouse Gas (LC GHG) emissions, encompassing raw material extraction and power plant operation. Five scenarios were analyzed. Two scenarios related to using sawdust and agroforestry residue for biomass fuel in the aging CFPP. The other three scenarios used biomass fuel from Calliandra wood harvested from tropical forests, production forests, and marginal land, which produced GHG emissions from Land Use Change (LUC). This study demonstrates that sawdust and agroforestry residue can reduce global warming impacts compared to coal. The LUC in higher carbon stock land will increase global warming impacts, while the LUC in lower carbon stock land will reduce global warming impacts. A decrease in the aging CFPP efficiency, when coal is converted to 100% biomass, will cause an increase in global warming impacts.