Assessing proposed decarbonisation strategies in the Lao PDR using open-source climate, land, energy and water systems (CLEWs) modelling

In accordance with the Paris Agreement, Laos has outlined sector-specific decarbonisation targets to achieve by 2030 in its Nationally Determined Contribution (NDC). However, by focusing on maximising decarbonisation efforts, the synergies and trade-offs between climate, land, energy and water systems (CLEWs) have been overlooked. This study utilises the open-source energy modelling system (OSeMOSYS) to assess the impacts of four decarbonisation measures on Laos’ CLEWs. A series of scenarios over 2020-2070, including a sensitivity analysis, were devised to compare emis-sions, costs, land cover changes, energy consumption and water usage. The results show that Laos’ forestry sector target is infeasible considering other sectors’ land requirements. Increasing forest cover to 60% of land area would require reducing crop production by 8,830,000 tonnes and in-creasing crop imports at the cost of $91,200,000 between 2020 and 2030. The sensitivity analysis highlights power export growth in determining emissions; with Laos’ reliance on coal production to meet power export demands, the energy-based NDC targets are inconsequential. This study demonstrates the need for a nexus-thinking approach in policymaking to account for the secondary effects of decarbonisation measures on resource systems. This conclusion provides a foundation for Laos’ next NDC and offers a framework for assessing decarbonisation pathways in other countries.