Carbon Snapshots
A CarbonEmissionSnapshot captures the state of a project's emissions at a point in time. Use snapshots for trend reporting — "how have our emissions changed from tender to handover?"
What a Snapshot Stores
| Field | Purpose |
|---|---|
ProjectId | Owning project. |
TakenAt | Timestamp. |
Note | Free-text description ("Post-design", "Pre-tender"). |
TotalEmissions | All scopes summed. |
Scope1Emissions / Scope2 / Scope3 | Per-scope totals. |
ItemCount | Number of emission rows captured. |
VerifiedCount | Number of verified rows. |
CreatedByUserId | Who took the snapshot. |
Taking a Snapshot
- Open Carbon → Snapshots.
- Click Save Snapshot.
- Enter an optional note.
- TX1 records the current aggregate totals.
Snapshots are append-only — you cannot edit history.
Comparing Snapshots
Carbon → Snapshots → Compare:
- Pick two snapshots (or "current state" vs a snapshot).
- View per-scope delta, total delta, item count delta.
- Export the comparison to CSV / PDF.
Useful for:
- Design-to-tender carbon change tracking.
- Before / after an optimisation workshop.
- Quarterly ESG reporting.
Accessing Programmatically
The Carbon service exposes:
SaveEmissionSnapshotAsync(projectId, note)→ persists a new snapshot.GetLatestSnapshotAsync(projectId)→ most recent.GetPreviousSnapshotAsync(projectId)→ second-most-recent.GetSnapshotsAsync(projectId, limit)→ a page of recent snapshots.
Best Practice Cadence
- Post-design — baseline figure.
- Pre-tender — verified numbers submitted to client.
- Mid-construction milestones — for tracking against targets.
- Handover — final reconciled position.
Limitations
- Snapshots do not copy the underlying row data — only the aggregate totals. Drill-down after the fact is not possible.
- Snapshots cannot be "restored" — use Allocation Scenarios if you need to roll data back, or the .tx1 package format if you need a full backup.
Retention
Snapshots stay with the project. If you archive a project, the snapshots archive with it.