Hexi Biogas Recovery and Utilization Project

Audit Analysis

The Hexi Biogas project is a VCS-registered biogas recovery project in China using AMS methodologies, with VVB-confirmed additionality and no material findings. However, the project-specific modeled baseline, absence of a stated buffer pool, inconsistent leakage treatment across documents, and a significant under-delivery relative to the PDD's lifetime estimate (verified ERR is roughly 29% of the pro-rata expectation) raise moderate concerns about baseline robustness and permanence safeguards.

Project Description

Red Flags

• ⚠Verified ERR of 42,272 tCO₂e is only ~29% of the pro-rata expectation (~146,900 tCO₂e) derived from the PDD's lifetime estimate of 385,133 tCO₂e over the 7-year crediting period, suggesting the baseline may be overly optimistic or the project underperformed
• ⚠Buffer pool percentage is not stated in any available document, leaving permanence risk unquantified for a biogas project where system failure could lead to reversal
• ⚠Leakage treatment is inconsistent: the monitoring report (Jan 2026) deems leakage negligible with a 0% deduction, while the validation report (Sep 2024) indicates leakage was not addressed at all
• ⚠Internal contradiction within the monitoring report itself: the baseline is described as both 'modeled' and 'measured' in the same document (dated 2026-01-08)

Credit Vintages