SÜTAS AKSARAY BIOGAS PLANT

Audit Analysis

The SÜTAS Aksaray biogas cogeneration project is a Gold Standard small-scale activity with VVB-verified additionality and no reported reversals, but it carries notable gaps: no buffer pool is stated, the 0% leakage deduction lacks a documented justification, and the verified emissions reductions for 2024 are roughly double the pro-rata ex-ante expectation, raising questions about the conservatism of the original estimate. The verification report (July 2025) resolved 23 corrective actions and issued an 'OK' opinion, yet the low extraction confidence and several null fields in the extracted record limit the depth of assurance available.

Project Description

Red Flags

• ⚠Leakage deduction of 0% with justification recorded as 'not addressed' in the 2025 verification report, while the 2016 verification report indicated it was quantified — the more recent document is privileged, leaving the current leakage treatment undocumented.
• ⚠Verified ER of 107,385 tCO2e for the 2024 monitoring period is approximately 197% of the pro-rata ex-ante expectation (~54,480 tCO2e per year from a 381,358 tCO2e lifetime estimate over 7 years), a near-doubling that is not clearly explained by a design change in the extracted record.
• ⚠Capture of methane is stated as legally required in the 2025 monitoring report but not in the 2024 PDD; if legally mandated, this weakens the additionality claim for the methane-recovery component.

Credit Vintages