Abstract Laos, the world’s second-largest net electricity exporter, faces dual challenges in its energy and agricultural sectors. While the country exports significant hydroelectric power to neighbouring nations, it remains dependent on electricity imports during dry seasons at unfavourable prices. Concurrently, Laos imports all its chemical nitrogenous fertilisers, exposing its agricultural sector to global price volatility. This study explores the potential of redirecting surplus electricity towards green ammonia production to address both issues. Using an open-source capacity expansion model of the Lao power sector, we analyse scenarios considering different power expansion plans and climate-induced variations in hydropower generation. Our results indicate that Laos could produce ∼1 Mt of green ammonia annually by 2030, potentially reaching ∼2 Mt by 2050. This production could satisfy domestic fertiliser demand and create export opportunities. Climate variability could significantly impact production potential, with dry conditions reducing production by 26% and wet conditions increasing it by 50% relative to the base scenario. Additional scenarios incorporating non-hydro renewable energy sources like solar PV and Wind and the transfer of power capacity into the control of the Lao government, post the termination of concessionary agreements, show potential for doubled production. The study emphasises the importance of climate-resilient infrastructure planning and regulatory frameworks for successful implementation. This research contributes to Laos’ ongoing efforts to develop its first national green hydrogen and ammonia roadmap, positioning it as a pioneer among Least Developed Countries in fossil-free hydrogen and ammonia production.