The availability of natural gas as feedstock for nitrogen fertilizer production continues to decline, while its price increases, encouraging the search for renewable feedstocks for the future green urea industry. Renewable feedstocks include waste biomass, hydrogen from solar PV‐electrolysis, and the combination of these feedstocks with natural gas. The selection of a green production strategy is a critical step in the trade‐off between economic and environmental considerations. The aim of this work was to propose a green urea production strategy using a multi‐objective optimization (MOO) model to minimize production costs and environmental impacts by considering the future cost development of technologies and feedstock price for each technology in the time frame of 2020‐2050. The results show that green urea production can reduce production costs and greenhouse gas emissions, compared to conventional urea production. Biomass gasification technology fulfills the minimum requirements for production cost and CO₂ emissions from 2020 to 2035 and combined biomass gasification‐PV electrolysis without battery technology is the optimum process from 2040 to 2050.

Bioenergy with carbon capture and storage (BECCS) has the potential to produce negative emissions. This study assessed the overall energy efficiency and carbon dioxide (CO₂) avoidance costs and emission footprint following the integration of BECCS with a polygeneration system (BECCS-PS) for the co-production of green electricity and methanol. The process was simulated in Aspen Plus and Aspen HYSYS v.11. Oil palm empty fruit bunches were used as the feed in a biomass integrated gasification combined cycle power plant. The flue gas, which contained CO₂, was captured for methanol synthesis and carbon storage. Green hydrogen for use in methanol synthesis was produced through proton exchange membrane (PEM) electrolysis powered by solar PV (PV-PEM) and geothermal power with double-flash technology (GEO-PEM). The environmental impacts of the process were investigated by a life cycle assessment and the economic aspects were evaluated using the levelized cost method. The overall system efficiency was higher in the PV-PEM scenario than in the GEO-PEM scenario. For any production capacities, the green electricity generated from the BECCS-PS plant resulted in negative emissions. A biomass power plant with a low production capacity generated higher production and CO₂ avoidance costs than that with a larger production capacity. The CO_2 − eq emissions and costs for methanol production in the PV-PEM scenario were larger than those in the GEO-PEM scenario, with values of -0.83 to -0.70 kg CO_2 − eq/kg MeOH and 1,191–1,237 USD/ton, respectively. The corresponding values were − 1.65 to -1.52 kg CO_2 − eq/kg MeOH and 918–961 USD/ton, respectively, for the GEO-PEM scenario. Graphical Abstract