Probability that node SUB47 requires curtailment of the flexible tier, by hour. Band shows the 80% confidence interval — it narrows as the forecast horizon closes. Vertical gates are the contractual notice windows.
Signal ingestion
Six streams, three owners. The utility contributes grid state, the ISO contributes market and topology, the facility contributes its own load and backup posture. Each stream carries a completeness score — because the binding constraint on this whole system is usually data condition, not modelling.
Forecast engine
Node headroom is what actually binds — conductor rating minus native load minus the firm tier. Rating is not a constant: it falls when air is hot and still. The engine decomposes headroom, then converts the deficit into a calibrated probability rather than a point estimate, because the contract is priced against the probability.
| Issued at | Lead | P(curtail) | 80% CI | Depth req. | Gate |
|---|
Contract & settlement
The forecast becomes an obligation only when it passes a contractual gate. Each gate has a defined lead time, a probability trigger, and a required response from the facility. Settlement runs both directions — the discount earned against firm service, net of backup fuel, net of any non-performance penalty.
Settlement statement
| Obligation | Allowed | Used | Remaining | Status |
|---|---|---|---|---|
| Curtailment hours | 96 | 0 | 96 | Within budget |
| Events called | 12 | 0 | 12 | Within budget |
| Max consecutive hours | 6 | 0 | — | Within limit |
| Response compliance | 98.0% | — | — | Measured at gate close |
Regulatory evidence
Every forecast, notice, acknowledgement, dispatch and verification is hashed and chained as it happens. The commission does not have to trust the operator or the utility — it can verify the sequence. This is the layer that turns a private commercial arrangement into something a regulator can approve and a lender can underwrite.
Exhibit C — Ratepayer benefit calculation
Cedar Hollow DC-2 interconnects 250 MW at SUB47 under Schedule E-FLEX. Of that, 70 MW is contracted as interruptible and is dispatchable within a one-hour notice window. No transmission network upgrade is triggered, and no incremental generation capacity is procured to serve this load.
| Line | Value | Basis |
|---|---|---|
| Incremental load served | 250 MW | Executed agreement |
| Network upgrade cost | $0 | Avoided via flexible service |
| Incremental generation capacity | 0 MW | Served within existing envelope |
| Annual revenue, new load | $58.4M | Metered, Sch. E-FLEX rates |
| Contribution to fixed cost recovery | $41.2M | Net of marginal energy cost |
| Residential customers of record | 3,840,000 | FERC Form 1, 2025 |
| Average annual bill impact | −$10.73 | Downward pressure per customer |
Curtailment performance over the reporting period is attested by the chained event record referenced above. Any hour in which the facility failed to reduce to contracted depth within the notice window is excluded from the benefit calculation and assessed under §7.4.
Signal out
A grid data feed tells you what the market did. The stack above lets Headroom emit what the facility must do — with the contractual and evidentiary fields attached, so an autonomous scheduler can act on it without a human in the loop.
| Field | Who needs it |
|---|---|
| binding | The scheduler — decides whether to checkpoint or ignore |
| capability_mw | The utility — the depth we have physically demonstrated |
| chain_head | The commission — the record this event will be verified against |
| settlement | The CFO — what this event is worth or costs |