The night board

offpeak rests on a claim: intelligence has a time value. The token side of that claim is already settled, and it is wider than the headline discount.

• Patience is priced at −50%. OpenAI and Anthropic both publish batch tiers at half of list: a flat 2.0x spread for work that can wait.
• Haste is priced too. Hold the model and the venue constant and read the same sheet across its urgency tiers: gpt-5.6-sol is $8.00 / $40.00 per 1M tokens on OpenAI's fast tier against $2.00 / $10.00 on its batch tier — a 4x intra-venue urgency spread, on both legs, for the hour alone. Source: developers.openai.com/api/docs/pricing.

The promo caveat

gpt-5.6-sol's standard rate is promotional — the sheet says it runs at least through 2026-11-21, after which list is $5/$30. Fast and batch are both defined off that list (2x and 0.5x), so the promo moves the dollars and leaves the ratio: the 4x is the durable figure, the prices are the perishable ones. Both are in the SDK rather than in prose — offpeak.prices.urgency_spread("gpt-5.6-sol") returns 4.0, and promo_decay() returns the step-up the date will bring.

The night board marks the same claim against the other side of the trade: the grid the compute runs on. Every night it records what power and carbon actually did between the evening peak and the small hours, from open, keyless sources. The grid's spread is not published anywhere — it has to be observed — and on the night of 2026-08-20 the ERCOT Houston hub marked 3.94x between its evening peak and the trough that followed, against the 4x a venue charges for the same hour of impatience.

The two sides of the grid do not move together, which is the point of marking both. On 2026-08-18 and 08-19, CAISO's carbon ran cleaner at the evening peak than in the small hours — spreads of 0.76x and 0.73x — because the sun that serves the California evening has set by midnight. Cheap hours are not automatically clean hours, and a board that only recorded price would have implied otherwise.

→ Read the board

How it works

Two passes over the same night, run by a scheduled workflow:

Pass	When	What it records
quote	19:00Z	The night ahead — carbon forecast, day-ahead power
mark	06:30Z	The night just finished — carbon actuals

A night runs 16:00Z–07:00Z: it opens with the 17:00 BST evening peak and closes after the 00–05 BST trough, so one span carries both windows the board compares.

Output lands on the board-data branch — nightly/BOARD.md plus the raw JSON per night — because main is protected and would reject a nightly bot push.

Settled runs are a different ledger

BOARD.md observes; it spends nothing at any venue. Runs that actually executed and actually billed go in nightly/SETTLED.md on the same branch, written by tools/settle_report.py from the receipts in receipts/ — never by hand — and published by a manual workflow, because a settlement is a deliberate act.

Every settled row carries its scale, and the column is not decoration. A few dozen jobs proving the mechanics end to end and a production book are both real settlements and are not the same evidence. A ledger that lets a reader confuse them is doing marketing rather than accounting, so the scale is printed before the money is.

Sources

• Carbon — NESO carbon intensity, GB, keyless.
• Power, GB — Octopus Agile day-ahead unit rates, GB region C, keyless.
• Power, US — CAISO SP15 and ERCOT Houston day-ahead hourly, via gridstatus, keyless.
• Carbon, US — EIA-930 hourly generation by fuel for the CAISO and ERCOT balancing authorities, through the EIA Hourly Grid Monitor. Needs a free API key; without one the column records itself unavailable and nothing else changes.
• Tokens — the published price sheets, not a measurement: OpenAI and Anthropic.

All are public and free. The board costs nothing to run and spends nothing at any venue.

Honest limits

• Four zones, unevenly covered. GB carbon and GB power are half-hourly and complete. CAISO SP15 and ERCOT Houston are day-ahead hourly prices, not settled real-time ones.
• US carbon is derived, GB carbon is measured. NESO publishes an intensity; EIA does not. The US columns are computed from EIA-930's hourly generation mix times EIA's own CO2 coefficients and fleet heat rates — every input published, the product an estimate, and marked "basis": "derived" in the record so it is never confused with a measurement. It counts generation, not consumption: imports and the carbon already stored in a battery are outside what the method can see, and the share of generation EIA files under "other" is reported per night rather than averaged in.
• EIA runs about a day behind. The 06:30Z mark usually lands before EIA has published the night it is marking, so the US carbon columns are often empty at first sight and fill in on a later re-mark. A column that is not there yet is recorded as unavailable, never as zero.
• The token column is published, not observed. The 2.0x and the 4x are read off price sheets; only the grid columns are measurements. A published number and a marked one are different kinds of claim, and the board should not blur them.
• Observation, not advice. The board records what the grid did. It does not forecast, and offpeak does not currently schedule against it — the SDK routes on published token prices alone.
• Carbon actuals lag roughly two hours. The 06:30Z mark clears the 00–05 BST trough comfortably; the tail of the night can still be sparse.
• A dead source costs its column, not the run. Legs degrade independently, and a night where both sources are down is recorded as unavailable rather than guessed at.