Design and analysis of biomass-to-ammonia-to-power as an energy storage method in a renewable multi-generation system

Abstract

To solve the problem of unevenly distributed renewables and increase their penetration, large-scale energy storage is necessary. Green hydrogen is suitable for bulk energy storage; however, it still faces storage problems. Therefore, green ammonia has been proposed as a substitute for hydrogen. The combination of renewables and green ammonia production can achieve cross-sector decarbonization. However, the potential of green ammonia as an energy carrier requires further investigation. This paper reports the design and analysis of a renewable multi-generation system for electricity, heat, and green ammonia, where biomass-to-ammonia-to-power is used as an energy storage method. This concept combines renewable power generation, biomass chemical-looping ammonia production, and direct ammonia fuel cells. The results indicated that the maximum energy and exergy efficiencies were 60.1% and 56.3%, respectively. The system provides 29,582 t·y-1 ammonia and 3,525,305 t·y-1 hot water and captures 171,550 t·y-1 of carbon dioxide. The optimal proportion of key components and relevant design criteria were also determined through sensitivity analysis as well. Compared to systems involving power-to-ammonia-to-power, the higher efficiency, lower electricity consumption for ammonia production, and carbon dioxide capture make biomass-to-ammonia-to-power a promising energy storage method for multigeneration systems.