Treat energy attribute instruments explicitly as ledger objects, not just documentation. For market-based Scope 2 accounting, record certificate type (REC, GO, I-REC), unique serial/ID, vintage (generation period), issuing region, supplier, and retirement date. Reference each certificate to the specific consumption it claims to match; anything unmatched should default to the relevant residual mix or grid-average factor. Always produce and store both location-based and market-based results side-by-side to meet disclosure requirements and enable cross-checks.
Apply the Scope 2 quality criteria: temporal matching (at least annual, with increasing preference for closer matching), geographic matching (same market/balancing area), and exclusive claims (evidenced by retirement in a recognized registry). For supplier-specific factors, capture evidence of the supplier’s emissions factor methodology and eligibility under the quality criteria. Model contract structures (e.g., physical/virtual PPAs, green tariffs) with attributes for contract tenor, delivery profile, and certificate conveyance to avoid double counting when contracts span entities.
Build controls that prevent reuse of a retired certificate ID, flag out-of-market or out-of-vintage applications, and reconcile certificate volumes to metered consumption. Store audit artifacts (registry screenshots, retirement certificates) as immutable attachments linked to transactions.
Key Takeaway: Track EACs as first-class ledger items with IDs, matching rules, and retirements to credibly support market-based Scope 2 results alongside location-based disclosures.