Process dynamics in a hydrogen-based energy storage system

The BioGenerator is a technology that was recently invented and is used for the biological conversion of hydrogen to electricity. Its main application is in the re-electrification of hydrogen in hydrogen-based energy storage systems for the smoothing of the variability in wind and solar power generation. Therefore, BioGenerator operation is highly dynamic. The core of the BioGenerator is a bioreactor where principal microorganisms Leprospirillun ferriphilum oxidize Fe2+ to Fe3+. The dynamics of the process of energy storage affects the temporal characteristics of the bioreactor. The BioGenerator remains idle during the peaks of power generation of renewable power where Fe2+ remaining in the bioreactor is continuously consumed biologically. Likewise during the valleys in power generation Fe3+ is consumed electrochemically and Fe2+ accumulates. The effect of periodic interruption on the operation of the iron-oxidizing bioreactor was studied in this work. Our results show that idling of the BioGenerator for less than half a day has no negative effect on returning to the initial performance, while longer idling periods result in a small temporary reduction in bioreactor performance. Similar dynamics were observed in both stand-alone bioreactor as well as in a bioreactor incorporated in a complete BioGenerator system for hydrogen re-electrification. Additionally, operation of the closed loop BioGenerator system revealed hysteresis effects on the steady state bio-oxidation rate correctable with brief interruption of operation.

Automated summary

The BioGenerator is a newly invented technology for the biological conversion of hydrogen to electricity, mainly used in hydrogen-based energy storage systems for dynamic operation. Research showed that short idle periods have no significant negative impact on the performance of the bioreactor, but longer idle periods can result in temporary performance reduction.