Minting QETs: How Verified Producer Data Becomes an On-Chain Token

For natural gas producers, RNG facility operators, carbon-storage projects, and the MRV teams and sustainability engineers running the data systems behind them, minting QETs is the supply-side process that turns verified primary data into a registry-grade token that can be discovered, acquired, and retired downstream. This page walks through the workflow end to end — who participates, what data flows in, how verification works, what gets stamped on-chain at issuance, and how the registry structurally prevents the same physical unit from being minted twice. The goal: a producer, a Measurement Partner, or an analyst trying to understand emissions token minting for the first time should leave this page knowing exactly how the process operates and exactly what the resulting token guarantees.

Minting a QET, in one paragraph. Minting is the supply-side step that turns verified producer data into an on-chain Quantified Emissions Token. Producers (and Measurement Partners acting on their behalf) submit primary MRV data; the relevant methodology runs (QET-NG, QET-RNG, QET-CCS, or QET-ELEC); an accredited ISO 14065:2020 verifier signs off under ISO 14064-3 reasonable assurance; and the token issues on the EarnDLT registry on Hedera Hashgraph with the verified attributes — carbon intensity, geography, MRV tier, methodology version (including R&D GREET 2025 reference dataset where applicable), IPCC AR5 GWP100 factor set, and the verifier of record — recorded immutably on-chain.

For the full marketplace context

What a QET is in the first place

Minting is the first stage of the QET lifecycle. It's where verified primary data leaves the producer's MRV stack and becomes an on-chain certificate that the rest of the market can transact against. Three properties define what makes a QET-grade issuance different from a self-attestation or a producer-direct PDF:

• Primary data, not estimates. Every issuance is anchored to site-specific measurement from the producer's facility. Continuous monitoring, segment-level OGMP 2.0 reporting (where applicable), and the underlying four-tier data-quality hierarchy (site-specific primary → process-specific primary → peer-reviewed secondary → industry-average secondary) feed the methodology. Estimates and industry averages are the lowest tier, not the default.
• Third-party verification. No producer issues a token on its own authority. An accredited ISO 14065:2020 verifier reviews the producer data under ISO 14064-3 reasonable assurance — the higher of the two assurance levels in the standard — and signs off before the token can issue.
• On-chain immutability. Once issued, the token's production-side attributes are immutable. The producer's verified data, the methodology version, the verifier of record, and the timestamp are written to the Hedera ledger and cannot be modified. Subsequent lifecycle events (transfer, retirement) extend the chain of custody; they do not rewrite what issuance established.

The combination is what makes a Greentruth-issued QET defensible under the kind of audit and regulator scrutiny that's becoming standard in 2026 and beyond. Self-attestations and spreadsheet records don't survive that scrutiny anymore; QETs issued under this discipline do.

How double counting is structurally prevented

The supply side of the QET lifecycle involves two roles:

Producers are the entities that operate the physical asset generating the environmental attribute — the natural gas producer, the RNG facility (anaerobic digester, landfill gas plant, agricultural waste stream), the carbon-storage operator, or the renewable electricity project. The producer holds the rights to the environmental attribute and is the legal entity that ultimately issues the token. Producer onboarding is governed by the EarnDLT Platform and Greentruth Marketplace Governance Framework Section 6.1.7: entity verification via Dun & Bradstreet D-U-N-S Number validation, KYC, AML screening, and project registration with environmental-attribute rights documentation.

Measurement Partners are dMRV providers and third-party data operators authorized to submit primary measurement data on the producer's behalf. A Measurement Partner might be a continuous-monitoring vendor running the methane sensors at a wellpad, an EPA Subpart W aggregator handling reporting flows, or a specialized digital MRV firm operating the producer's data systems. The Measurement Partner submits data through the same EarnDLT data ingestion API the producer uses, under a documented Data Provider Agreement, with no co-certification liability — the producer remains the entity that owns the data and the resulting token.

The two-role structure matters because most large producers don't operate their MRV stacks in-house anymore. Measurement Partners exist so the data submission step can be operated by the actual entity running the sensors, with the producer retaining ownership and accountability for what the resulting token asserts.

For the broader platform onboarding context

End-to-end, the mint flow runs through five stages. Each has documented authority, defined data flows, and a clear hand-off to the next stage.

• Producer onboarding and project registration. Producer completes KYC, entity verification, AML screening, and project registration per Governance Framework §6.1.7. Project metadata (facility location, operational capacity, technology type, applicable methodology) is recorded; environmental-attribute rights documentation is attached.
• Primary MRV data ingestion. Producer (or designated Measurement Partner) submits site-specific measurement data through the EarnDLT data ingestion API or the platform UI. Data feeds the relevant methodology — QET-NG for natural gas, QET-RNG for renewable natural gas, QET-CCS for geologically stored CO₂, QET-ELEC for renewable electricity — in the format the methodology specifies.
• Methodology application. The methodology runs against the producer's verified inputs and the appropriate reference datasets (R&D GREET 2025 for natural gas where applicable; methodology-specific factor sets for the other classes). IPCC AR5 GWP100 factors (CH₄ = 28, N₂O = 265) are applied to produce a carbon-intensity result expressed in kgCO₂e per unit (MMBtu, kWh, tonne).
• Third-party verification under ISO 14064-3 reasonable assurance. An accredited ISO 14065:2020 verifier reviews the producer data, the methodology application, the uncertainty quantification, and the materiality threshold. The verifier issues an unmodified verification opinion meeting the materiality threshold before any token can issue. Verifier independence is enforced under the Governance Framework's separation-of-functions rules.
• On-chain mint. The token mints on the EarnDLT registry on Hedera Hashgraph, with the verified attributes attached. The mint event timestamps to the Hedera ledger; a webhook fires to integrated downstream platforms; the token enters the Marketplace inventory available for discovery.

For a producer running a steady-state operation, stages 1 and 2 are continuous; stages 3, 4, and 5 run on the accounting period the methodology specifies (typically monthly or quarterly for QET-NG and QET-RNG). For a first-time producer, the onboarding and first verification engagement is where the timeline sits — typically 6–12 weeks from onboarding kickoff to first issuance, depending on the producer's MRV stack maturity.

For the methodology behind QET-NG mints

For the methodology behind QET-RNG mints

The data that flows into issuance determines the data quality of every downstream claim. The methodologies specify what's required for each QET class, but the underlying expectations are consistent.

For QET-NG natural-gas issuance, the producer submits:

• Wellpad-level methane measurements (continuous monitoring preferred; periodic where continuous is not technically feasible).
• Site-specific emission factors where producer-grade primary data exists; segment-level OGMP 2.0 Level 3–5 reporting where the producer participates in OGMP 2.0.
• Production volumes (MMBtu) with calibrated meter readings and metering accuracy traceable to national standards.
• Operator entity-level factors where the operator has filed an Operator Entity-Level CI Declaration with qualifying entity-level data (EPA GHGRP Subpart W, OGMP 2.0 L3–L5, FERC Form 2, 10-K/Sustainability under NGSI v2.0).
• Pipeline operator identification and injection point for downstream pathway construction.

For QET-RNG (renewable natural gas), the producer submits the analogous biogenic data set, including feedstock characterization, facility GPS coordinates, injection point identification, and the producer-level methodology inputs that feed the five-point verification gateway (injection point identified, delivery point identified, pipeline connectivity confirmed, volumetric equivalence, temporal matching).

For QET-CCS and QET-ELEC, the methodologies specify equivalent primary-data requirements appropriate to the attribute class — storage-pathway and permanence attributes for CCS; hourly-granularity attribution for ELEC.

Across all classes, the four-tier data-quality hierarchy applies: site-specific primary data is preferred, secondary and industry-average data are the lowest tier and used only where primary is unavailable. The hierarchy is captured explicitly on the resulting QET so a downstream buyer can reason about the underlying data quality.

How the data-quality hierarchy works

For OGMP 2.0 segment-level reporting

Verification is the gate between producer data and on-chain issuance. No QET issues without an unmodified verification opinion from an accredited third party.

The verifier must be accredited to ISO 14065:2020 by an acceptable accreditation body (ANAB, UKAS, DAkkS, INMETRO, or another International Accreditation Forum signatory), with sector-specific accreditation appropriate to the certificate class. For QETs supporting EU Methane Regulation Article 28 submissions, additional accreditation under ISO/IEC 17029:2019 and explicit scope coverage for oil-and-gas methane emissions verification apply.

The verifier's scope on an issuance:

• Confirm the completeness and accuracy of the producer's primary MRV data.
• Confirm the methodology was applied correctly, including the appropriate reference dataset version and the IPCC AR5 GWP100 factor set.
• Confirm the uncertainty quantification and the materiality threshold (typically ≤5% for individual certificate batches, ≤2% for aggregated portfolios).
• Confirm the producer's environmental-attribute rights and the absence of double-counting with regulatory programs or other registries.
• Issue an unmodified verification opinion under ISO 14064-3 reasonable assurance, signed by the lead verifier with credentials and dated.

Reasonable assurance is the higher of the two assurance levels in ISO 14064-3. It is what the major regulatory frameworks (EU Methane Regulation Article 8, CARB LCFS, EPA RFS) and the major reporting frameworks (GHG Protocol, SBTi, CDP, TCR) expect for high-integrity environmental-attribute claims. Limited assurance — the lower level — is not sufficient for EU Methane Regulation Article 28 submissions and is increasingly disallowed for Scope 1 fossil-CO₂ reduction claims under the major reporting frameworks.

Verifier independence is enforced under the Governance Framework's separation-of-functions rules: no consulting services to the same client within 2–3 years, mandatory lead-verifier rotation every 3 years, fixed-fee compensation that is not contingent on verification outcomes, and documented impartiality assessments per ISO 14065:2020 Section 7.

How ISO 14064-3 underpins the platform

A QET is not an opaque token. Its attribute schema is published, versioned, and machine-readable, so every downstream consumer — buyers, ESG software, regulators, auditors — can reason directly over what the mint encoded.

Universal attributes on every issued QET:

• Unit. The defined physical unit the token represents — 1 MMBtu of natural gas, 1 MMBtu of RNG thermal energy, 1 MWh of electricity, or 1 tonne of geologically stored CO₂.
• Carbon intensity. Expressed in kgCO₂e/MMBtu (or per appropriate unit), with CH₄, CO₂, and N₂O converted via IPCC AR5 GWP100 (CH₄ = 28, N₂O = 265).
• Geography and pathway. Basin, operator identification, validated pipeline pathway across the Lower-48 network (where applicable), or facility location for non-pipeline classes.
• MRV tier. Where the producer's data sits in the four-tier data-quality hierarchy.
• Methodology version. Including the R&D GREET 2025 reference dataset version for QET-NG mints (recorded immutably in greetVersion), or the methodology-specific version pin for the other classes.
• Verifier of record. The accredited third-party verifier whose ISO 14064-3 reasonable-assurance opinion underwrote the mint, with the lead verifier's credentials referenced.
• Mint timestamp. Recorded on the Hedera ledger.

Token-specific attributes layer on within each class — producer-carried grades for QET-NG, biogenic carve-out and Compliance Passport status for QET-RNG, hourly granularity for QET-ELEC, storage permanence for QET-CCS. The schema is JSON-machine-readable; the Machine-Ready API exposes every attribute through REST endpoints and webhook events.

The practical implication for producers: the attribute schema is the contract that every downstream consumer will interact with. Getting the underlying data quality right at issuance time is what determines whether the resulting token commands premium pricing — and survives auditor or regulator review when retired against a reporting claim.

For the full Machine-Ready API surface

When verification is complete and the verifier's unmodified opinion is attached, the platform issues the token. Three things happen at issuance:

The token mints on the EarnDLT registry. The registry is the blockchain infrastructure on Hedera Hashgraph that records every QET event. The mint transaction writes the token, its attributes, and the verifier's opinion reference to the ledger with a cryptographically signed timestamp. The transaction is immutable; once written, the production-side attributes cannot be modified by any party, including EarnDLT.

The token enters the Marketplace inventory. Buyers running saved searches that match the new token's attributes (basin, MRV tier, methodology version, certificate class, regulatory eligibility) see the new token surface automatically. Webhook events fire to integrated buyer-side platforms — ESG software, in-house GHG accounting, ERP systems — so the new inventory is queryable across the buyer-side stack without polling.

The producer's wallet receives the token. The producer's multi-signature enterprise wallet, provisioned during onboarding, takes custody of the newly issued token. From there, the producer can hold, transfer, or list the token through the Discovery / Acquire workflows.

The choice of Hedera Hashgraph as the underlying ledger is deliberate. Hedera's consensus mechanism produces deterministic finality with fast settlement times, low and predictable transaction fees, and an asymmetric Byzantine fault tolerance model that suits high-throughput registry-grade environmental-attribute operations. For producers, the practical implication is that issuance settles quickly and at predictable cost; for buyers and verifiers, the implication is that the audit chain — every event timestamped, every signature preserved — is durable across the seven-year retention window the Governance Framework requires.

Hedera Token Service documentation

For the blockchain architecture in detail

Every issuance produces an audit trail that travels with the token for its entire lifecycle. Five elements are stamped on-chain:

• Producer attestation and project registration record. The producer entity, the registered project ID, and the producer-attestation that environmental-attribute rights are held.
• Primary data references. Pointers to the underlying MRV data — calibration records, meter readings, OGMP 2.0 reports — preserved per the Framework's seven-year retention requirement.
• Methodology and version. The specific methodology applied (QET-NG, QET-RNG, etc.), the version pin, and (for QET-NG issuances) the R&D GREET 2025 dataset version stored immutably in greetVersion.
• Verifier opinion reference. The verifier of record, the lead verifier's credentials, the ISO 14064-3 opinion date, and the materiality threshold applied.
• Issuance timestamp and registry transaction hash. The Hedera ledger transaction that recorded the issuance, with cryptographic signing linking the certificate to the underlying data.

Single-mint enforcement is the other half of the integrity story. The registry layer structurally rejects any attempt to issue a second token for the same physical unit — the same MMBtu, the same MWh, the same tonne. The enforcement happens at the Hedera infrastructure level, not at the application policy level, which is why double-counting prevention on Greentruth is structural rather than contractual. A specific physical unit produces exactly one token; that token traverses the lifecycle once; the token cannot be re-issued under any circumstance.

For an auditor or regulator opening a retirement record years downstream, the issuance audit trail is the bottom of the chain. Trace from the retirement back through every transfer, back to the original mint event, and the trail terminates at the verifier's opinion and the producer's primary data — every step preserved immutably on-chain.

How double counting is structurally prevented

For the mass-balance accounting layer over mints

A few boundaries worth surfacing directly:

QET minting is not self-attestation. No producer issues on their own authority. Every issuance requires an accredited ISO 14065:2020 verifier signing off under ISO 14064-3 reasonable assurance before any token can issue. The verifier is structurally independent of the producer under the Governance Framework's separation-of-functions rules.

QET minting is not a way to upgrade a weak data stack. The methodology runs against whatever the producer's MRV stack actually produces. If the underlying data is industry-average secondary, the resulting token will carry an industry-average MRV tier — visible to every downstream buyer. The process does not invent data quality the producer doesn't have; it encodes the data quality the producer does have, transparently.

QET minting is not a one-way Scope 1 transfer. Issuing a QET does not move the producer's direct emissions off the producer's Scope 1 inventory. Scope 1 stays with the entity that physically combusts the fuel; the QET conveys the verified environmental attribute (carbon intensity, pathway, methodology, biogenic content where applicable), not the GHG Protocol scope itself.

QET minting is not the only step. An issued token is registry-grade inventory; it is not yet a retired reporting claim. Discovery, acquisition, and irrevocable retirement against a specific buyer claim are the downstream steps that turn inventory into a defensible disclosure. Issuance is the first stage of the lifecycle, not the last.

QET minting is not vulnerable to double-issuance. Single-mint enforcement at the registry layer structurally prevents any attempt to issue a second token for the same physical unit. The enforcement is mechanical, not policy-based.