A new biomass gasification driven hybrid system for power and liquid hydrogen cogeneration: Parametric study and multi-objective evolutionary optimization

The purpose of this paper is focused on introducing a new layout of an electricity and liquid hydrogen cogeneration power plant and evaluating its performance from the exergo-economic and environmental stand points. The system is based on the combination of a biomass gasification gas turbine cycle, a Rankine cycle, an electrolyzer unit, and a hydrogen liquefaction cycle. A parametric model is firstly developed to study the sensitivity of the system performance on the main design parameters (including biomass flow rate ṁbiomass, gas turbine inlet temperature TGT, compressor pressure ratio PR, and steam turbine inlet pressure PSRCT). Afterward, the optimal operation of system is selected using by a multi-objective optimization approach. The observations revealed that m˙biomass is the most effective design parameter. The optimal design parameters are obtained as ṁbiomass = 1.94 kg/s, TGT = 1421 K, PR = 5.52, and PSRCT = 3886 kPa, which results in the maximum electricity and hydrogen production of 3377 kW and 14.8 kg/h together with minimum total cost rate of 86.61 $/h. At this condition, the optimal environmental index is 1.09 kgCO₂/kWh.