Australia’s ACCU CAC deliveries near 400,000 in Dec

Australia's carbon abatement contract (CAC) holders delivered almost 400,000 Australian Carbon Credit Units (ACCUs) to the federal government in December 2025, driving the strongest quarterly increase in the country's cost containment mechanism in more than a year.

A total of 39 CAC holders delivered 380,528 ACCUs to the Clean Energy Regulator (CER) to fulfill contract commitments with the Commonwealth, according to an Argus analysis of the latest update to the CAC register published by the CER this week.

Separate rounded quarterly data published by the CER this week show that ACCU holdings in its cost containment mechanism rose by around 0.4mn to approximately 4.8mn in October-December 2025 — the highest increase for any quarter since the third quarter of 2024.

All ACCUs delivered to the CER under the CACs since January 2023 have been held in the cost containment mechanism, which can only be accessed by facilities under the country's safeguard mechanism at fixed prices that rise each year, starting at A$75/t CO2e ($51.10/t CO2e) for the 2023-24 year and at A$82.68/t CO2e for 2025-26 — levels not expected to be recorded in the secondary market within the next few years.

Largest deliveries

Australia's largest landfill gas operator LMS Energy delivered the highest volume to the CER in December, with 78,321 ACCUs from three separate CACs, while EDL Energy was also among the holders with the largest deliveries (see chart).

LMS Energy had led ACCU issuances in December at 176,687 units, while EDL Energy received 83,911 ACCUs.

The CER in early December announced a long-awaited decision offering a voluntary permanent exit arrangement for fixed delivery CACs.

Holders of nearly 300 active CACs with a combined remaining volume of around 84mn ACCUs will need to deliver at least 25pc of the outstanding volume of ACCUs under their contracts as of 1 January 2025 to be eligible for a 60pc discount on their exit payment. This would then allow them to sell the remaining 75pc contracted volume elsewhere, potentially unlocking up to more than 60mn ACCUs into the secondary market within the next five years.

The news sparked uncertainties in the market, with some participants expecting potentially more supply constraints in the near and medium-term because some CAC holders may decide to fill the minimum 25pc requirement as soon as possible to exit their contracts.

This could lead to a lower share of ACCU issuances going to the market, driving prices up, market participants noted.

Argus assessed generic ACCU prices at A$37.50/t CO2e on 23 January, up by A$0.50/t CO2e on the week, on the back of increased buying ahead of the safeguard surrender deadline of 31 March 2026.

By Juan Weik