Technical and economic evaluation of solar hydrogen production by supercritical water gasification of biomass in China

A novel thermochemical method for solar hydrogen production was proposed by state key laboratory of multiphase flow in power engineering (SKLMFPE) of Xi'an Jiaotong University. In this paper, a technical and economic evaluation of the new solar hydrogen production technology was conducted. Firstly, the advantages of this new solar hydrogen production process, compared with other processes, were assessed and thermodynamic analysis of the new process was carried out. The results show that biomass gasification in supercritical water driven by concentrating solar energy may be used to achieve high efficiency solar thermal decomposition of water and biomass for hydrogen production. Secondly, the hydrogen production cost was analyzed using the method of the total annual revenue requirement. The estimated hydrogen production cost was 38.46RMB/kg for the experimental demonstration system with a treatment capacity of 1 ton wet biomass per hour, and it would be decreased to 25.1 RMB/kg if the treatment capacity of wet biomass increased from 1 t/h to 10 t/h. A sensitivity analysis was also performed and influence of parameters on the hydrogen production cost was studied. The results from technical and economic evaluation show that supercritical water gasification of biomass driven by concentrated solar energy is a promising technology for hydrogen production and it is competitive compared to other solar hydrogen production technologies.