Techno-economic and environmental impact assessment of hydrogen production processes using bio-waste as renewable energy resource

There is a wide spectrum of biological wastes, from which H-2 production can generate clean energy while minimizing environmental degradation. This study aims to conduct techno-economic and environmental impact assessment of major hydrogen production processes such as dark, photo and solid-state fermentation, microbial electrolysis cell (MEC), gasification, pyrolysis and plasma. From the technological point of view, the dark fermentation has shown better performance in comparison to the other processes. However, the hybrid dark fermentation with photo-fermentation and MEC has shown higher performances with around 1 L H2/g organic waste. Regarding the economic aspect, the cheapest H-2 production belongs to gasification and fermentation with approximately 2 US$/g and 2.3 US$/g followed by plasma (2.4 US$/g), pyrolysis (2.6 US$/g), MEC (2.8 US$/g), and photo-fermentation (3.5 US$/g). Regarding the potential environmental impact, the fermentation process showed the lowest greenhouse gas emission with 15 kg CO2-eq/kg hydrogen followed by gasification, MEC and plasma. Regarding the potential commercial applications, gasification is the most mature with the highest possible technology readiness at level 9.

Automated summary

This study conducted a techno-economic and environmental impact assessment of major hydrogen production processes. Dark fermentation showed better technological performance, but hybrid dark fermentation with photo-fermentation and MEC had higher performance. Gasification and fermentation were the cheapest methods, with fermentation having the lowest environmental impact. Gasification was identified as the most mature and commercially viable application.