An efficient hybrid power generation system by integrating the biomass-fueled gas turbine with existing coal-fired power plants

To enhance the biomass utilization efficiency and cut down the carbon footprint, a novel hybrid power generation system is proposed, which innovatively integrates biomass gasification with a gas turbine and an existing coal-fired power plant. In the proposed system, the raw syngas derived from biomass gasification is cooled by transferring thermal energy to the feedwater streams of the coal-fired unit. The cleaned syngas is exploited by a gas turbine for power generation, then the exhaust is further employed to heat the secondary air and the feedwater in cascade. Comprehensive energy and exergy analyses of the proposed system have been conducted and results indicate that the equivalent energy and exergy efficiencies of biomass-to-electricity soar to 54.28 % and 45.82 %, respectively. Moreover, further system modification has been developed, revealing that the corresponding efficiencies of the modified hybrid system increase by 0.51 % and 0.42 % points, respectively. Regarding the carbon reduction effect, attributable to the inherent carbon neutrality of biomass, the CO2 emission intensity of the hybrid system decreases by 265.23 g/kWh (34.83 %). Economic analysis shows that the levelized cost of electricity of the biomass power generation in the hybrid system is reduced by 5.43 $/MWh with higher net present value and shorter dynamic payback period compared with the reference biomass integrated gasification combined cycle. This work offers a new approach to the efficient biomass power generation and highlights biomass as a potential alternative fuel to reduce coal consumption.