The Great Mekong Sub-region (GMS), consisting of Cambodia, the Lao PDR, Myanmar, Thailand, and Vietnam, has enormous potential to achieve the decarbonisation of electricity systems by expanding the potential of renewable energy and energy efficiency. The mitigation policy instrument would have a major role in maximising the renewable energy and energy efficiency potentials of decarbonising electricity systems. But the current climate policy framework consisting of an aggregation of each country’s mitigation efforts by Nationally Determined Contributions would face institutional barriers to identify emission sources and account for emission reduction.

In fact, based on the experience of past mitigation schemes, such as the Clean Development Mechanism (CDM), any country-based mitigation initiative could be inefficient because the boundary of the mitigation scheme would not match with the place of implemented mitigation actions, which would hinder implementation of mitigation activities.

To tackle those barriers, regional climate policy instruments such as the ASEAN Power Grid, i.e. an integrated electricity system across the countries, would have the following positive impacts. First, it physically bridges the potential renewable energy production areas and demand areas. Second, it creates an opportunity to bring regional mitigation initiatives that would eliminate the complexity of identifying and accounting for mitigation impacts.