Thermodynamic evaluation of biomass gasification with air in autothermal gasifiers

► Chemical energy values are 2.16-5.20 times as the physical energy values. ► Chemical exergy values are 4.50-13.45 times as the physical exergy values. ► Efficiencies mainly increase first and then decline when ER/temperature increases. ► Higher carbon and hydrogen content generates higher energy and exergy values. ► Higher ash content results in lower energy and exergy values/efficiencies.