The rulebook, published in full.
Version 0.3. A self-published, open draft.
This document defines what is measured, how it is attributed, how each hour is graded against its basin, how the record is made self-verifiable and tamper-evident, and how double counting is prevented.
It is written to be recognized by the bodies that confer recognition. It does not confer certification on itself. Legitimacy comes from outside, and we would rather say that plainly than imply otherwise.
Settled rules are marked as settled. Open ones are carried openly as the research program rather than hidden as gaps. What is not yet decided is listed in Research.
Status legend
Decided.
A proposed default.
Routed to the research agenda.
Prescription and vintage
The prescription: local by designsettled
A gallon in a dry basin is not a gallon in a wet one, so the water ceiling is local by design. Each jurisdiction gets a prescription: its own gate values, derived from cited inputs, dated, versioned, and ratified before they bind anything. Where no basin prescription exists yet, the labeled interim default (1.8 liters per kilowatt-hour, strict under) is in force, and every surface that shows it says it is a default.
The vintage: the past is never re-gradedsettled
Every certificate carries its vintage: a snapshot of the prescription in force at mint, sealed inside the record's hash. A later change to any dial re-grades nothing; each record stands under the rules that were in force when it was written. The version in force today is v0.3.
The unit and quantification
Canonical definitionsettled
The RCC is a direct renewable-energy-certificate analog: generation produces a certificate; clean, water-passing compute produces a credit. The GPU-hour is the headline unit. Hardware type and form factor are mandatory certificate attributes, and no cross-hardware fungibility is asserted; the energy consumed is recorded alongside each credit as a measured normalization basis.
The issuance boundarysettled
The job is the issuance and provenance boundary. A job that runs forty clean, water-passing GPU-hours mints forty credits, backed by that job's composite provenance record. Carbon is the denominator that sets the count; water is a qualifying gate that changes eligibility, not the count.
Eligibility: what makes a GPU-hour mintable
Clean-window eligibility, inheritedsettled
A window is a clean window when its electricity consumption is matched to a retired granular certificate for that window: temporal match, regional deliverability, and retired exactly once. Cleanliness is born at the generator and carried by that certificate; the RCC references it and does not re-issue it. In the v1 reference implementation the granular certificate is stubbed and windows are detected by a grid carbon-intensity threshold (≤100 gCO₂/kWh, anchored to the EU-taxonomy low-carbon line). This replaces an earlier wind-plus-solar-share cutoff, which was not grid-neutral. The same threshold yields opposite verdicts across grids by design: MISO Central clears it almost never, a hydro grid almost always. The difference is policy, not technology.
The factor table, one on every gridprovisional
The gate compares against a computed intensity: each fuel in a window's reported generation mix carries a published factor, and the window's carbon intensity is the share-weighted sum. One table serves every grid, so the verdict moves with the mix, never with a per-grid dial. These are the values in force.
| Fuel | gCO₂/kWh | Source | Dated |
|---|---|---|---|
| Coal | 980 | IPCC/EIA lifecycle assessments | Draft v0.1, June 2026 |
| Natural gas | 450 | IPCC/EIA lifecycle assessments | Draft v0.1, June 2026 |
| Nuclear | 12 | IPCC/EIA lifecycle assessments | Draft v0.1, June 2026 |
| Wind | 11 | IPCC/EIA lifecycle assessments | Draft v0.1, June 2026 |
| Solar | 45 | IPCC/EIA lifecycle assessments | Draft v0.1, June 2026 |
| Hydro | 24 | IPCC/EIA lifecycle assessments | Draft v0.1, June 2026 |
| Other | 700 | Other-fossil/petroleum median over EIA-930's masked OTH share | Resolved 2026-07-06 |
Other earns its own factor because EIA-930 carries a share the reporting does not name: confidentiality-masked generators plus petroleum, waste, biomass, geothermal, and net storage. That share once contributed zero carbon, harmless at MISO Central's 1 to 3 percent, wrong wherever masked generation runs 10 percent or more. The 2026-07-06 resolution filled the slot with an other-fossil and petroleum median chosen conservatively: an unverifiable share must not inherit a clean pass, and erring high on a possibly biogenic share fails a window that might have passed, the recoverable direction for this instrument.
That resolution moved no verdict on either live grid: Hydro-Québec rose from about 22 to about 53 gCO₂/kWh, still well under the gate, and MISO Central's cleanest trailing-year hour stayed far above it. A grid does not fail this gate by rounding error: a 10 percent coal share alone contributes 98 gCO₂/kWh, essentially the whole 100 gCO₂/kWh ceiling. The table carries its version id inside every certificate's vintage, so a factor change is a dated version event that re-grades nothing already minted.
Water gate, originated and qualifyingsettled
The executing facility must stay under a per-window, WUE-derived water threshold. Indirect water (the water consumed generating the electricity, via grid-mix water-consumption factors against the live feed) is computed from real data now. Direct and cooling water is modeled from published WUE benchmarks until a facility pilot meters it; every record flags which inputs are measured and which are modeled. Reservoir net evaporation is included at a conservative net factor, because the meter carries one water-factor table on every grid and lets the grid mix, not a per-grid rule, do the talking. The realized MISO Central basis is about 313 gallons per megawatt-hour. The cooling-mix fractions are measured from EIA-860 (2024 cooling codes) crossed with EIA-923 (2024 net generation) over the MISO Central footprint. The threshold in force is 1.8 liters per kilowatt-hour, strict under: a facility passes only by beating it, not by matching it. It is the labeled interim default where no basin prescription exists yet, and per-basin prescriptions, each derived from cited inputs, replace it basin by basin as dated version events.settled
Prescriptions in forcesettled
The interim default above is in force wherever no basin prescription exists. Three basins carry their own prescriptions today; each renders on the Basin Ledger with its instruments attached.
Aquadrio certifies at 0.30 liters per kilowatt-hour, strict under. The basin spans 9 HUC-8 hydrologic units; the full set, and the argument behind every constant, is in the derivation memo (PRESCRIPTION_METHOD_MEMO_2026-07-29).
Aquadrio certifies at 0.30 liters per kilowatt-hour, strict under. The boundary is the Basin the statute itself defines, carried as QC-SLRB; the instruments and the argument are in the derivation memo (PRESCRIPTION_METHOD_MEMO_2026-07-29_BASIN2).
Aquadrio certifies at 0.083 liters per kilowatt-hour, strict under: the first dial tightened by a basin's own ratified budget. Ratified and contested, stated together: the basin's safe yield is under active adjudication, the prescription carries the instrument in force today, and it re-derives on judgment. Registry id CA-IWV; the chain is in the derivation memo (PRESCRIPTION_METHOD_MEMO_2026-07-29_BASIN3).
The double-counting firewall
Everything an RCC claims sits on one side of a single line. The inherited attribute, that a job ran on renewable energy, is born at the generator and already carried by its certificate; the RCC references the retired certificate and does not re-claim the energy attribute. The originated attributes, which the operator creates and the generator cannot issue, are the timing (shifting compute into clean windows), the restraint (holding through dirty, peak, or over-water windows), the water provenance, and the job-level granularity. Because the underlying certificate is retired exactly once and the RCC references rather than re-issues it, double-counting will be prevented structurally, not by attestation, when the reference is bound to the registry. That reference is present on every certificate today, null and flagged DEFERRED until the connection lands.settled
Issuance, serialization, retirement
The RCC follows the renewable-energy-certificate lifecycle. On a job's completion, one credit is issued per certified GPU-hour, each with a unique identifier. Credits are serialized in a thin RCC ledger that Aquadrio owns, the system of record for the new attribute, referencing the retired granular certificate held in an external energy-attribute registry. A given GPU-hour, and the certificate it references, can back exactly one RCC, enforced in the ledger. Transfer and retirement semantics mirror certificate retirement and are exercised when a holder or retirer persona exists.settled
Claims, and the honest-framing guardrails
An RCC may make the comparative claim that this compute was produced more cleanly, with accounted water, than uncertified compute, backed by traceable, hashed provenance, plus the attribute claims of certified timing, evidenced restraint, per-job water provenance, and hardware typing. It may not claim to be first to measure or schedule clean compute: software carbon intensity already measures it, and grid-responsive scheduling is commercialized. It may not claim "compute as currency" as original, may not re-claim the inherited energy attribute, and may not assert real-time operation where the grid feed is delayed. On securities discipline: an RCC offered before a market exists is a forward bet on future recognition; IPO or stock framing is not used, speculative-value language is constrained, and legal review is required before any external offering.settledopen
Verification and assurance
Any holder can independently check an RCC today: recompute the carbon from the recorded inputs, and confirm the water figures against their measured-or-modeled flags. The third check, that the referenced granular certificate is retired and bound to no other claim, waits on the registry connection; the reference field is present on every certificate, null until then, and flagged DEFERRED. The sha256 hash detects tampering. The standard is published as an open draft and designed to be recognizable by an accreditation of issuers and verifiers and a product certification; it claims no third-party certification it has not received.
Changelog
v0.3, July 2026Initial open draft. Defines the RCC attribute class, the two eligibility gates, the double-counting firewall, the issuance and verification lifecycle, and the permitted and prohibited claims.
Clean-window gate stated as grid carbon intensity at or under 100 gCO₂/kWh, replacing the earlier renewable-share proxy (retained only as an informational statistic). Indirect-water basis reconciled to about 313 gallons per megawatt-hour, hydro net reservoir evaporation included.
Water-gate boundary made strict-under at 1.8 liters per kilowatt-hour: a facility passes only by beating the ceiling, not by matching it. Certificate vintage added: every new record carries the prescription in force at mint inside its hash, so a later dial change re-grades nothing.
Declared basis restated, no dial moved: 1.8 stands as the labeled interim default ceiling, in force where no basin prescription exists yet, and the earlier average-WUE framing is withdrawn (LBNL 2024 primary verification). Per-basin prescriptions arrive as dated, ratified version events.