IEA Data Shows Australia Underreports Fugitive Methane Emissions by Up to 92%

International Energy Agency estimates of actual methane emissions from Australia's coal, oil, and gas sectors in 2022 exceed official national inventory figures by approximately 81% for coal mining and 92% for oil and gas, according to new analysis by the Institute for Energy Economics and Financial Analysis. Correcting the under-reporting would require industrial facilities covered by Australia's Safeguard Mechanism to double their annual decarbonisation rate from 4.9% to 9.8% and more than halve their total emissions by 2030.

The IEA's 2022 country-level methane estimates incorporate satellite-detected emissions alongside publicly reported data, providing a more comprehensive picture than national self-reporting systems. The discrepancy between IEA figures and Australia's National Greenhouse Gas Inventory corresponds to approximately 28 million tonnes of CO2 equivalent — more than 6% of total national emissions. Australia's national inventory figures for total fugitive emissions from coal, oil, and gas in 2022 were unchanged from 2020-21 at 48.8 million tonnes of CO2 equivalent, suggesting the under-reporting is systemic rather than a single-year anomaly.

Methane's climate impact is disproportionate to its mass: it warms the atmosphere 82 times more than CO2 over a 20-year period and 30 times more over 100 years. Methane accounts for approximately 18% of global emissions and is estimated to have contributed roughly 30% of the global temperature rise since the Industrial Revolution. Under the revised baseline, the Safeguard Mechanism's cumulative emissions ceiling of 1,233 million tonnes of CO2 equivalent would require approximately 24 million tonnes of additional covered facility reductions — significantly tightening the effective cap on Australia's largest industrial emitters.

IEEFA urges Australia to develop a concrete domestic methane reduction plan, noting the country signed the Global Methane Pledge committing to cut methane emissions 30% below 2020 levels by 2030 without specifying any domestic action. New satellite monitoring technologies can help improve near-term methane assessments for onshore coal mines, which account for the majority of under-reporting. The United States has introduced a Methane Emissions Reduction Program with waste emissions charges starting at US$900 per metric tonne in 2024, rising to US$1,500 from 2026 — a model IEEFA suggests Australia should consider.

Key figure — 28 MtCO2e — estimated volume of fugitive methane emissions omitted from Australia's national greenhouse gas inventory