Energy valorization strategies of fallen leaves and woody biomass in a based downdraft gasification-engine power plant

•Add wood improve the operating flexibility of fallen leaves gasification.•As woody biomass (WB) fraction increases, the specific fuel consumption decreases.•As WB increases, the power plant efficiency decreases due to higher biomass’ LHV.•Ash fusibility temperatures of biomasses set the power plant’s performance. Herein the effect of ash-rich biomass (fallen-leaves, FL) mixed with woody biomass (WB) on the thermodynamic performance of a bioenergy power plant based on a downdraft gasifier coupled to an engine-generator (