Australia’s Coal Mine Emissions Underreporting: 10 Million Tonnes in Question

A recent study by Reputex has revealed a potential underreporting of over 10 million tonnes of CO2-e annually from Australia's coal mines. This discrepancy arises from voluntary emissions reporting changes, allowing open-cut mines to choose between state-based emissions factors or company-led, site-specific estimates.

Switching to mine-specific estimates has led to a 65–70% drop in reported emissions, with total coal mine emissions estimated to be 10.6 Mt CO2-e higher under state-based factors. These self-reported figures, lacking third-party verification, have significantly reduced greenhouse gas reporting at individual mines—by up to 1 million tonnes per year, according to Ember's earlier analysis.

This underreporting poses risks for Australia’s carbon credit market. If advanced satellite technologies revise emissions upwards, demand for carbon credits could surge, potentially driving up prices. The planned review of the Safeguard Mechanism in 2026–27 could trigger a carbon credit price spike by the decade’s end.

The Climate Change Authority raised integrity concerns over company-led reporting and urged the government to review this system. While the government agreed, it also announced the phasing out of state-based factors, potentially enabling further emissions write-offs of 3 Mt CO2-e.