Assessing power system vulnerability to climate-related stressors and shocks: The case of Indonesia

Climate change and extreme weather are increasing the vulnerability of power systems globally, particularly in emerging economies such as Indonesia. Yet, existing studies often assess these impacts in isolation, focusing on individual components or specific hazards, leaving system-level effects—at provincial and national scales—under-examined. To address this gap, we develop an integrated, spatially explicit approach to assess an energy system's climate-related vulnerabilities and their impacts, and apply the approach to Indonesia. We quantify climate-based vulnerabilities in generation and transmission infrastructure as well as in demand by distinguishing between stressors, i.e., gradual temperature rise due to gradual climatic change, and shocks, i.e., sudden, disruptive hazards due to sea-level rise, flooding, and landslides. Through geospatial data analysis, derating models, and regression analysis, we examine existing and planned assets and demand under historical and future climate conditions. Results indicate that in Indonesia, both existing and planned generation are likely to experience stress, which implies a reduction in usable capacity, even as electricity demand increases due to temperature rise, and transmission assets face potential disruption from climate change-induced shocks. Together, these effects contribute to a potential erosion of reserve margins by up to 36 percentage points under the medium-term 10-year plan in the year 2034, indicating a substantial reduction in system resilience. In the largest system, Jawa–Madura–Bali, the reserve margin falls to 26.5%, below its 35% planning threshold. Importantly, the findings suggest that a growing share of future capacity expansion may be absorbed by climate-induced losses, implying that adaptation-related investments may increasingly be required simply to maintain existing supply levels rather than meet future requirements. We conclude that climate considerations need to be embedded more explicitly into power sector planning during the transition toward net zero.