Small-Scale Gasification-Based Biomass Power Generation

Introduction Gasifying biomass to produce a combustible gas provides the possibility for much more efficient overall conversion of a given biomass resource into electric power than is possible with traditional combustion-based technologies. In particular, gasified biomass can be used to power internal combustion engines (ICEs), gas turbines, and fuel cells, all of which are able to produce electricity at considerably higher efficiency than boiler/steam-turbine systems of comparable size. In addition, ICEs, gas turbines, or fuel cells coupled with biomass gasifiers have the potential for considerably lower capital investment requirements than comparably-sized boiler/steam turbine systems. In the size range below 5 MWe, spark-ignition or compression-ignition engines are the technologies of choice today for gasification-based power generation from biomass (Fig. I). Fuel cells and micro-gas turbines coupled with biomass gasifiers will offer considerably higher efficiencies at small scales compared to internal combustion engines [Williams, 1998], but such advanced technologies are still under development. This paper presents an overview of technology and economics of biomass-gasifier/internal combustion engine technology, with some discussion of applications in the context of Jilin Province.