Abstract We report the results of a systematic evaluation of the redeployment of surplus hydropower electricity to produce green hydrogen (H2), ammonia (NH3) and urea (CH4N2O) in Lao PDR. Participatory system mapping (PSM) workshops convened across multiple Lao PDR ministries revealed both direct and indirect opportunities and risks as probable consequences of green H2, NH3 and urea production. Participants debated and prioritized green urea fertilizer to replace “grey” imports; coal co-firing; and fuel cells as the products that contribute to the opportunities and manage the risks identified by the PSM process. Techno-economic modelling indicates the levelized cost of urea (US$467/tonne) is competitive with Thai imports, associated with opportunities for trading carbon offsets. Carbon credits were not sufficient to offset the additional co-firing costs of coal generation, and fuel cells are a likely future enterprise. A targeted capacity building and training program was a central pillar of a systems-based dissemination strategy to develop necessary technical and planning skills and community and awareness raising. The collated research results represent an integrated foundation to draft the Lao PDR National green H2 and NH3 road map and action plan, and a cross-sectoral revision of energy transition development plans.