4. The Promising Role of Thermochemical Conversion in Sustainable Power Generation

The rising demand for petroleum-based fuels, coupled with escalating environmental concerns, has encouraged the scientific community to focus on exploring alternative energy resources for power generation. Biomass, being renewable, carbon–neutral, and abundant, has significant potential for generating power with minimal environmental impact. Biomass energy has an estimated annual production capacity of 181.5 billion metric tonnes of which only 8.2 billion metric tonnes are presently utilized. There is significant potential in terms of technological advancement for the conversion of biomass energy. Among the various biomass conversion routes, the thermochemical conversion process has gained prominence since the late nineteenth century. This well-established technology encompasses various categories such as pyrolysis, torrefaction, carbonization, liquefaction, gasification, and combustion, depending on the feedstock and desired end product. The present chapter provides a comprehensive overview of the various thermochemical conversion processes, their working principles, and operating criteria. Furthermore, this chapter briefly explores various power generation pathways such as steam power plants, gasifier-IC engine combined technology, gasifier gas turbine combined technology, and gasification fuel cell combined technology available for thermo-chemically converted biomass. The various limitations and challenges associated with the thermochemical conversion process have been reported in this chapter. Currently, the global power generated from biomass sources is about 764.2 TWh as of 2021 having an average annual growth rate of about 7%. The government initiatives aimed at promoting biomass-based power generation are also discussed in detail. Moreover, techno-economic assessments, recent advancements in this field on the commercial scale, and their potential impact on CO₂ reduction are examined.