AUTHOR=Poluzzi A. , Guandalini G. , Guffanti S. , Martinelli M. , Moioli S. , Huttenhuis P. , Rexwinkel G. , Palonen J. , Martelli E. , Groppi G. , Romano M. C. 

TITLE=Flexible Power and Biomass-To-Methanol Plants With Different Gasification Technologies

JOURNAL=Frontiers in Energy Research

VOLUME=Volume 9 - 2021

YEAR=2022

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2021.795673

DOI=10.3389/fenrg.2021.795673

ISSN=2296-598X

ABSTRACT=The competitiveness of biofuels may be increased by integrating biomass gasification plants with electrolysis units which generate hydrogen to be combined with the carbon-rich syngas. This option allows to increase the yield of the final product by retaining a higher amount of biogenic carbon and to improve the resilience of the energy sector by favoring electric grid services and sector coupling.
This paper illustrates a techno-economic comparative analysis of three flexible power and biomass to methanol plants based on different gasification technologies, namely direct gasification, indirect gasification and sorption-enhanced gasification. The design and operational criteria of each plant are conceived to operate both without green hydrogen addition (baseline mode) and with hydrogen addition (enhanced mode), following an intermittent use of the electrolysis system, which is turned on when the electricity price allows an economically viable hydrogen production. The methanol production plants include gasification section, syngas cleaning, conditioning and compression section, methanol synthesis and purification, and heat recovery steam cycle, to be flexibly operated. Due to the high oxygen demand in the gasifier, the DG-based plant obtains a great advantage to be operated between a minimum load to satisfy the oxygen demand at high electricity prices and a maximum load to maximize methanol production at low electricity prices. This allows to avoid large oxygen storages with significant benefits for Capex and safety issues. The analysis reports specific fixed capital investments between 1823 and 2048 €/kW of methanol output in enhanced operation and LCOFs between 29.7 and 31.7 €/GJLHV. Economic advantages may be derived from a decrease in the electrolysis capital investment, especially for the DG based plants which employ the greatest sized electrolyzer. Methanol breakeven selling prices range between 545-582 €/t with the 2019 reference Denmark electricity price curve and between 484-535 €/t with an assumed modified electricity price curve of a future energy mix with increased penetration of intermittent renewables.