Indonesia’s commitment to the Paris Agreement and its Nationally Determined Contribution (NDC) is not adequately reflected in the significant CO₂ emissions from fossil-fuel-intensive energy sectors, despite the enormous potential of renewable energy sources in the country. The ongoing coal regime has led to electricity oversupply and air pollution problems. Despite the huge challenges for Indonesia, a just energy transition away from fossil fuel is crucial. This study aims to explore the ideal energy mix and key emission reduction pathway in Indonesia in achieving a just energy transition using the least-cost optimisation energy modelling tool OSeMOSYS. Six scenarios are modelled over the period 2015–2050 including coal phase-out, NDC, the Just Energy Transition Partnership (JETP), and carbon tax implementation. The results highlight that solar power, geothermal power, and hydropower are the alternatives for coal decommissioning. Despite the large-scale investment in renewable energy under the NDC and JETP scenarios, emissions could be reduced by 55% and 52%, respectively, by 2050. Moreover, Indonesia’s current carbon tax rate will not lead to a significant emission reduction. Three recommended policies include (1) accelerating CFPP retirement; (2) imposing an aggressive carbon tax rate; (3) prioritising investment in solar technologies.

Indonesia’s commitment to the Paris Agreement and its Nationally Determined Contribution (NDC) is not adequately reflected in the significant CO2 emissions from fossil fuel-intensive energy sector, albeit enormous potential of renewable energy sources in the country. The ongoing coal regime, which has been a major contributor to Indonesia’s economy and employment sector, has led to electricity oversupply and air pollution problems. Although it poses a huge challenge for Indonesia, a just energy transition away from fossil fuel is crucial. This study aims to explore the ideal energy mix and key emissions reduction pathway in Indonesia in achieving a just energy transition using a least-cost optimisation energy modelling tool OSeMOSYS. Six scenarios are modelled over 2015-2050 including coal phase-out, NDC, Just Energy Transition Partnership (JETP), and carbon tax implementation. The result highlights that solar, geothermal, and hydropower are the alternatives for coal decommissioning. Despite the large-scale investment in renewable energy under the NDC and JETP scenarios, emissions could be reduced by 55% and 52%, respectively, by 2050. Moreover, Indonesia’s current carbon tax rate won’t lead to a significant emission reduction. Three recommended policies include (1) Accelerate CFPP retirement; (2) Impose an aggressive carbon tax rate; (3) Prioritise investment on solar technologies.

Indonesia's emission reduction commitment and clean energy transition target emphasises the importance of energy system modelling for analysing and projecting Indonesia's capacity, resource availability, and future conditions in achieving these objectives. Utilising energy systems modelling based on adequate and reliable data enables policymakers to select the most optimal alternatives in energy planning. Aligned with the U4RIA (Ubuntu, Retrievability, Repeatability, Reconstructability, Interoperability, Auditability) concept, this database may facilitate various related stakeholders in obtaining this comprehensive and detailed energy data, while the data gathering and processing can also be applied to other developing countries. This country-specific dataset covers the historical data of electricity generation, demand, installed capacity, capacity factor, technical lifetime, renewable energy potentials, costs, and its projections up to 2050. The data in this article is ready to be used for energy system and modelling research.

Indonesia’s emission reduction commitment and clean energy transition target emphasises the importance of energy system modelling for analysing and projecting Indonesia’s capacity, resource availability, and future conditions in achieving these objectives. Utilising energy systems modelling based on adequate and reliable data enables policymakers to select the most optimal alternatives in energy planning. Aligned with the U4RIA concept, this database may facilitate various related stakeholders in obtaining this comprehensive and detailed energy data. The country-specific data of this study includes the historical data of electricity generation, demand, installed capacity, capacity factor, operational lifetime, renewable energy potentials, costs, and its projections up to 2050.