We construct current policy projections by combining a APERC and PLN projections for the power sector, with our own projections of energy non-CO2 and non-energy emissions. Emissions from the huge pipeline of captive coal plants are largely missing from APERC, IEA, and PLN projections (on-grid). We quantify emissions from these power plants using Global Coal Plant Tracker data on operation start date, lifetime, capacity, and assume default capacity and emissions factors (Global Energy Monitor, 2023).
For energy-CO2 we combine the reference “Business-as-usual” scenario from the Asia Pacific Energy Research Centre (APERC), which "assumes current policies and trends continue" (APEC, 2022) and Indonesia’s 10-year electricity supply plan RUPTL 2021–2030 (Republic of Indonesia, 2021b). We use coal, oil, and gas emission factors from the IEA’s Current Policies Scenario for Southeast Asia to estimate emissions from planned generation.
We add these energy-CO2 projections to energy non-CO2 and non-energy emissions projections to obtain current policies projections for total emissions excl. LULUCF. For each sector we create a projection based on the growth rates forecast in Indonesia’s Second Biennial Update Report (Republic of Indonesia, 2018a). We develop a range by looking at other possible sector-specific trends. For industry we apply GDP growth rates from our post-COVID GDP series, which includes forecasts from the IMF, World Bank, ADB, and OECD (ADB, 2023; IMF, 2023; OECD, 2023; World Bank, 2023). For agriculture, waste, and other sectors, we apply a five-year trend. The two alternatives create a minimum and maximum current policies projections for energy non-CO2 and non-energy emissions.
We subsequently harmonise these projections to historical data. The emissions levels are sensitive to the method of harmonisation. Thus, we apply two methods:
- Apply growth rates of the calculated scenarios to the last historical year (2022);
- Adjust all future years by the difference of the calculated scenario and the inventory in the last available year (2022).
Both methods are included in the range presented for current policy projections.