Indonesia

Historical emissions data for all sectors (excluding LULUCF) are sourced from the PRIMAP latest dataset, which provides data up to 2024 (Gütschow et al., 2025).

For LULUCF, historical emissions from 2000–2024 are taken from Indonesia's Fourth National Communication (NC4). Reported values are used directly for 2000, 2005, 2010, 2015, 2020, 2023 and 2024, while values for the remaining years are approximated from the figures in NC4. Data for 1990–1999 are sourced from the UNFCCC GHG inventory database. It is noted that Indonesia's reported LULUCF emissions have been revised substantially across successive submissions, from the Third Biennial Update Report (BUR3) to the First Biennial Transparency Report (BTR1) and again in NC4, without clear accompanying recalculation documentation. These revisions increase uncertainty around historical LULUCF series.

We quantify Indonesia’s 2030 target using the absolute emission levels from the 2022 Enhanced Nationally Determined Contribution (ENDC) as provided in the BTR1, and the 2035 target from the newly submitted 2035 NDC. These values are reported using Global Warming Potentials from the IPCC's Fifth Assessment Report (AR5).

The 2060 net zero target is quantified based on pathways in the 2035 NDC. These pathways project net emissions (excluding LULUCF) of 274-277 MtCO₂e in 2060, which can be interpreted as conditional targets for both low and high economic growth scenarios. We keep this value constant for 2060 and assumed a linear decline in total GHGs between 2030 and 2060.

Our current policy projections are presented as a range based on two scenarios:

• The upper end of the range (CPPmax) is based on extending the latest PRIMAP data year and applying the growth rate from the Current Policy Scenario (CPOS) outlined in the 2035 NDC.
• The lower end of the range (CPPmin) combines projections from multiple sources.
  • For the energy-sector CO₂ emissions, we use the Business-as-Usual (BAU) scenario from the 2025 APEC Energy Demand and Supply Outlook published by the Asia Pacific Energy Research Centre (APERC) and adjust the power sector emissions projections from Indonesia’s new Electricity Supply Plan (RUPTL 2025-2034), as the new RUPTL provides direct emissions estimates, eliminating the need to apply separate emissions factors. We assume energy non-CO₂ follows the same growth rate as energy CO₂.
  • For non-power sectors, projections are based on historical emissions, with growth rates applied from the CPOS scenario in the 2035 NDC.
  • Emissions from the large pipeline of captive (off-grid) coal plants are largely missing from main policy documents. We therefore quantify these emissions separately using the Global Coal Plant Tracker database. This involves using plant-specific data on operational start dates, lifetime, and capacity, along with default capacity and emissions factors.
  • The resulting energy-related CO₂ projections (from RUPTL and captive coal) are then added to our projections for energy non-CO₂ and non-energy sector emissions to derive the total emissions pathway (excluding LULUCF).

The planned policy projection also reflects a range, which is derived by subtracting the potential emissions savings from the full implementation of the Just Energy Transition Partnership (JETP) Comprehensive Investment and Policy Plan (CIPP) 2023, from our current policy scenarios.

• The upper end (PPPmax) is calculated by taking the CPPmax scenario and subtracting emissions savings from achieving JETP targets (e.g., 44% renewables in the power mix by 2030).
• The lower end (PPPmin) applies the same JETP-related emissions reductions to the CPPmin scenario.

The CAT uses Global Warming Potential (GWP) values from the IPCC's Fifth Assessment Report (AR5) for all its figures and time series. Assessments completed prior to December 2018 (COP24) used GWP values from the Second Assessment Report (SAR).