Several large coal mines have slashed their annual carbon emissions by more than half as a result of mandated changes to accounting methods that have prompted experts to question the reliability of key data underpinning one of Labor’s flagship climate policies.

According to data published by the Clean Energy Regulator, Glencore’s Collinsville and Clermont mines in Queensland’s Bowen Basin reported emissions reductions of 52 and 59 per cent, respectively, for 2023-24. However, neither facility recorded equivalent changes to production levels or operational efficiencies over the same period.