This book presents a comprehensive overview of important issues and topics concerning the combustion and cofiring of biomass and hydrogen-based fuels such as ammonia in the power generation sector. In recent years, the energy sector has been responsible for around three-quarters of global greenhouse gas (GHG) emissions. Cofiring of coal with agricultural and forestry wastes and low-emissions hydrogen and ammonia could reduce GHG emissions from power plants and may offer a cheaper option to achieve Net Zero Emissions (NZE). This book provides an updated review of combustion and co-combustion technologies, especially for ammonia and hydrogen cofiring, which includes technical issues, emission reduction, and by-product problems. It goes into an in-depth discussion of hydrogen and ammonia "exclusive" combustion for power generation to reduce CO2 emissions. The content caters to students, academic and industry researchers, and policymakers who are interested in decarbonizing power generation sectors using biomass and hydrogen-based fuels.