Breadcrumbs
Uncovering Indonesia's hidden methane problem
Indonesia’s underreporting of coal mine methane emissions could risk undermining the country’s efforts to meet its Global Methane Pledge commitments.
Available in: Indonesia
About
This report examines Indonesia’s coal mine methane (CMM) emission trends and sources. CMM estimation methods based on IPCC guidelines are overviewed and stacked against current CMM estimates. Independent estimates are also used as benchmarks to assess the likelihood of underreporting. Finally, we present recommendations to improve Indonesia’s monitoring, reporting and verification (MRV) framework as required by the Global Methane Pledge (GMP).
Executive summary
Indonesia’s coal mining emissions are greater than currently reported
Indonesia stands to gain great benefits by closely monitoring its methane emissions from coal mining as part of the Global Methane Pledge, including improved transparency, a deeper understanding of its methane problem, effective mitigation measures, heightened safety for mine workers, and increased support for project developers.
Wira A. Swadana Green Economy Program Manager, Institute for Essential Services Reform (IESR)
Indonesia is a signatory to the Global Methane Pledge, which aims to reduce methane emissions by 30% by 2030. The importance lies in the fact that it is the "underestimated" cause of greenhouse gas emissions after CO2. Knowing this fact, it is important to have this report to analyse the actions that the government and all relevant stakeholders need to take to mitigate climate change, especially in relation to methane emissions.
Introduction
Understanding Indonesia’s methane problem
Methane is the second most potent greenhouse gas. Over 150 countries, including Indonesia, have pledged to reduce man-made methane emissions, including those from coal mines.
In this chapter:
Coal mine methane is a general term for all the methane that is released during mining and post-mining operations. In Indonesia, coal bed methane (CBM) is a more commonly-used term which refers to extracted methane gas from coal seams—layers of coal in the earth’s crust—prior to mining activities and is a non-conventional fuel source acknowledged by the government to enhance energy supply.
Methane emission from coal mining depends on several factors, but underground mining typically releases more methane than surface mining due to deeper coal seams and higher coal rank. In underground mines, methane emissions come from degasification and ventilation systems, whereas in surface mines, emissions occur over a large surface area during coal extraction.
The energy sector represents nearly 40% of anthropogenic (man-made) methane emissions with coal mining representing one third of the emissions. Among methane emissions from coal mines, current estimates suggest that 84% of global CMM emissions come from underground mining. As satellite measurement techniques improve, the international scientific community is now openly questioning whether surface coal mines may emit significantly more methane than previously reported.
CMM emissions in Indonesia
Methane emissions from expanding coal operations are underestimated
Methane pollution from coal mining is the fastest growing emissions source across Indonesia’s energy sector. Yet, Indonesia could be underestimating its surface CMM emissions by up to eight times.
In this chapter:
These independent estimates are important as they provide scientific evidence to help countries improve their emission estimates for more effective climate action. For example, Australia increased its methane emission factors for surface coal mines in Queensland following an independent assessment. Similarly, Indonesia could reference these independent findings to improve its country-specific emission factors for methane emissions. This, in turn, would facilitate the identification of regions and coal mines responsible for producing the most CMM emissions and therefore provide clarity on where to focus mitigation efforts.
CMM underreporting
Why the government needs to re-assess its CMM estimate
The latest official estimate lacks clear assumptions and data disaggregation, resulting in high uncertainty. Our analysis suggests that CMM emissions are equivalent to the total wildfire emissions throughout Indonesia in 2022.
In this chapter:
Policy recommendations
Practical steps are available to improve CMM emissions reporting
Improving emissions MRV will enable Indonesia to better understand its methane problem, facilitating more effective mitigation measures. This will also bolster credibility and attract international support for climate action.
In this chapter:
MRVs should be conducted on a facility level to increase transparency and meet stakeholder demands for public disclosure. Each coal company with a production mining business licence (IUP OP) should report their GHG emission from mining operations at mine level, including CMM.
The approach for estimating GHGs, whether through emission factors or direct measurements, should prioritise transparency. The Directorate General of Electricity of Indonesia’s energy ministry has a good example on how APPLE Gatrik is used to track emissions from each power plant across the country. In addition, US EPA and Australia’s NGER provide other examples on how such emissions data is also available for public scrutiny.
Given that many major coal mining companies are publicly listed, methane emission from coal mining should also be incorporated into their sustainability reports. Consequently, the Financial Services Authority (OJK) needs to update its sustainability reporting guidelines to align with the Global Reporting Initiative (GRI) 305, ensuring coverage of the energy sector’s fugitive emission. Indonesian Coal Mining Association (ICMA) has also developed sustainability report guidelines in accordance with OJK, CDP and GRI standards.
Supporting Material
Methodology
Disclaimer
We have identified instances where reported emissions or estimates may significantly underestimate the actual amount of methane released. It is important to note that this information is intended for informational or educational purposes only and should not be construed as financial, legal, or other professional advice.
The data presented in this report is based on the materials outlined below. While the findings are derived from an analysis of this material, we cannot guarantee the completeness, accuracy, or reliability of the statements or representations arising from it. The Center of Data and Information of MEMR was contacted for comment prior to the publication of this report.
Methodology
Ember conducted a reverse calculation to identify methane emission factor by comparing CMM emissions in the Third Biennial Update Report (BUR) with coal production data from the Handbook of Energy and Economic Statistics of Indonesia (HEESI). The calculation method and conversion factors follow the latest IPCC guidelines on fugitive emissions.
Estimating CMM emissions in 2024 involved calculating both surface and underground emissions. For surface CMM emissions, we used IPCC average emission factors (1.2 m3/t for mining and 0.1 m3/t for post-mining). Coal production data was gathered from HEESI and a press release from MEMR. Coal production for surface mines in 2024 was assumed to be similar to that of 2023.
CMM emissions from two Qinfa’s underground coal mines are estimated using IPCC average emission factors (18 m3/t for mining and 2.5 m3/t for post-mining) for SDE-1 mine with mine depth of 180 – 410m and high emission factors (25 m3/t for mining and 4 m3/t for post-mining) for SDE-2 with mine depth of 440 – 650m. CMM emissions from existing underground mines were not estimated in this study due to data unavailability.
We used the latest Global Warming Potential (GWP) from the Sixth Assessment Report, setting the fossil-fuel methane GWP at 29.8. Emissions from forest and land fires in 2022 were sourced from a report by the Ministry of Environment and Forestry (MoEF).
IPCC guideline on tier approaches
There are three tier methods to estimate greenhouse gas emissions specified in the IPCC guidelines. Tier 1 approach is the most basic approach which estimates methane emissions by applying bulk coal production data with a global emissions factor. This simple method has the highest level of uncertainty. Tier 2 approach uses basin- or country-specific emission factors which represent average methane emissions in respective regions. Tier 3 approach employs direct measurement at the facility- or mine-level, making it the most accurate method and should be applied to gassy coal mines.
Coal mine methane estimation using satellite data
The study listed as Shen et al utilised a top-down approach incorporating 18 months of satellite measurements from TROPOMI (TROPOspheric Monitoring Instrument) satellite data to adjust GHG inventory models, including Global Fuel Exploitation Inventory (GFEI) v1 and v2, as well as the Emissions Database for Global Atmospheric Research (EDGAR) v6.
Global Energy Monitor coal mine methane estimates
The Global Energy Monitor (GEM) has developed a coal mine tracker to monitor more than 4,000 coal mines around the world, spanning various operational statuses, including over 400 active mines in Indonesia. Annual methane emissions are estimated at mine level using annual coal production, methane content and an emission factor coefficient. Methane gas content is estimated using the MC2M model, which follows Langmuir isotherm for the appropriate coal rank (sub-bituminous, bituminous and anthracite) and at the depth of mining. Finally, the emission factor coefficient is applied to estimate methane emission.
Acknowledgements
Our appreciation to Dr. Retno Gumilang Dewi (Bandung Institute of Technology), Indra Setiadi (Indonesian Ministry of Energy and Mineral Resources) and the Global Energy Monitor (GEM) for valuable inputs during the writing of this report. Eleanor Whittle and Christiane Yemen played key roles in peer-reviewing this report. Ardhi Arsala Rahmani and Rini Sucahyo significantly contributed through editing and enhancing the structure of this work. Reynaldo Dizon improved all aspects of data visualisation.
Header imageRescuers work at a coal mine after an explosion, in Sawahlunto, West Sumatera, Indonesia
Credit: Imago / Alamy Stock Photo