Quantified Emissions Token (QET): The Registry-Grade Standard for Verified Fuel Attributes

A Quantified Emissions Token is the unit that makes verified, location-specific emissions data trade like any other piece of structured information — auditable, retire-able, and durable enough to survive a third-party assurance review. This page explains what a Quantified Emissions Token actually is, why it lives on-chain, what it carries, and how it bridges into the carbon-accounting frameworks your reporting team already uses.

Quantified Emissions Token (QET). A machine-readable, ISO 14064-3-verified fuel- or electricity-attribute certificate issued on the EarnDLT registry (on Hedera Hashgraph). A QET carries the specific emissions attributes of a defined unit of fuel or electricity — for example, kgCO₂e/MMBtu of natural gas — and is retired on-chain to anchor a corresponding GHG claim. A QET is not a carbon credit, not an offset, and does not transfer Scope 1 emissions between parties.

See QETs in the Marketplace

A Quantified Emissions Token is a registry-grade certificate that says, in machine-readable form: this much of this fuel or electricity, from this source, has these verified emissions attributes — and here is the audit trail behind every one of them. Each QET ties a defined unit of physical energy (one MMBtu of natural gas, one MMBtu of RNG thermal energy, one MWh of electricity, or one tonne of CO₂ geologically stored) to its measured or modeled carbon intensity, its geography, the methodology version that produced it, and the verifier of record.

That precision is the point. The natural-gas value chain is opaque by default: emissions accrue across production, gathering and boosting, processing, transmission, storage, and distribution, often crossing multiple operators and jurisdictions before reaching a burner tip. A QET preserves the line of sight from primary data to the disclosed number — without it, the same load of gas can support contradictory claims at both ends of the pipeline.

Across the Greentruth platform, the QET is the unit of account. Every product surface — the Marketplace where QETs are discovered and acquired, the GasTrace Scope 3 Category 3 EAC tool, and the framework alignment exports — operates on top of QETs.

A QET lives on-chain because three properties matter to its users: single issuance, irrevocable retirement, and portable provenance. Anchoring each token on a public distributed ledger — Hedera Hashgraph, via the EarnDLT registry — gives those properties without forcing reporters or assurance providers to take any one company's word for them.

EarnDLT is the registry and tokenization infrastructure. It issues, verifies, and tracks every QET. Greentruth is the application layer that sits on top of EarnDLT — search, configuration, reporting, retirement — and includes the GasTrace product for downstream Scope 3 Category 3 reporting. Anchoring on Hedera means the mint, every transfer, and the final retirement of a Quantified Emissions Token are written to a tamper-evident, time-stamped public record an auditor can independently inspect.

On-chain anchoring also enables interoperability. The same QET can feed a CSRD disclosure in Brussels, an SB 253 filing in Sacramento, and a TCR report in Los Angeles — without the registry having to mediate the export. The token is the source; the framework export is the view.

Why blockchain matters here. Environmental markets fail almost exclusively at three points: double issuance (two certificates for the same physical unit), double use (the same certificate substantiating two different claims), and double claiming (two parties claiming the same retirement). Single-mint enforcement plus irrevocable on-chain retirement closes all three gaps structurally — not by policy.

A QET carries the attributes a reporter, auditor, or downstream software platform actually needs. The schema is methodology-versioned, so the values on the token map back to the exact methodology, data hierarchy tier, and verifier that produced them.

Every QET issued today carries, at minimum:

• Unit. The defined physical unit the QET represents (e.g., 1 MMBtu of natural gas, 1 MMBtu of RNG thermal energy).
• Multi-pollutant carbon intensity. Where applicable, CH₄, CO₂, and N₂O emissions, converted to kgCO₂e/MMBtu using IPCC AR5 GWP100 factors (CH₄ = 28, N₂O = 265).
• Geography and pathway. Basin, operator, and — for natural gas — the validated pipeline pathway across EarnDLT's 32,000-segment Lower 48 network model.
• MRV tier. Where the underlying data sits in the QET-NG methodology hierarchy: site-specific primary, process-specific primary, peer-reviewed secondary, or industry-average secondary.
• Methodology version. The exact version of the methodology and reference dataset (e.g., R&D GREET 2025) used to produce the value, refreshed annually within the first 30 business days of each year.
• Verifier of record. The accredited third-party that signed off on the underlying data under ISO 14064-3 reasonable assurance.
• Optional producer attributes. Where producers carry them, third-party grades (such as MiQ) are encoded directly on the token rather than referenced externally.

The same token is human-readable in PDF form and machine-readable in JSON form — both delivered to the holder's EarnDLT wallet on issuance and locked until payment confirmation, then portable for reporting, retirement, or transfer.

A Quantified Emissions Token is a fuel- or electricity-attribute certificate, not a carbon credit. The difference is not cosmetic. A QET conveys the verified attributes of a defined physical unit of fuel or electricity to whoever holds it; a carbon credit conveys the right to claim an offsetting tonne of avoided or removed CO₂e against a separate emissions inventory.

The methodology underneath each QET is explicit about what a token does not do:

• A QET does not transfer Scope 1 emissions between parties. The producer's combustion or fugitive emissions stay on the producer's inventory.
• A QET is not an offset. It does not substitute for abatement and is not designed to be netted against an unrelated tonne of CO₂e.
• A QET is not a voluntary carbon credit. It is not issued under the standards governing voluntary carbon markets, and it is not subject to the same reversibility and additionality framings.

How QETs compare to other instruments:

• Quantified Emissions Token (QET) — Verified emissions attributes of a defined unit of fuel or electricity. Used to substantiate Scope 1, Scope 2, and Scope 3 Category 3 reporting with primary data. Not a carbon credit, offset, or Scope 1 transfer mechanism.
• Renewable Energy Certificate (REC) — The renewable attribute of 1 MWh of electricity. Used for market-based Scope 2 accounting. Does not convey a measured carbon intensity for the underlying generation.
• Voluntary carbon credit — 1 tCO₂e avoided or removed elsewhere. Used for offsetting against a residual inventory. Not a fuel- or electricity-attribute claim.
• Spreadsheet attestation — A producer's self-reported claim. Pre-registry-era documentation. Not third-party verified, registry-anchored, or single-issuance-enforced.

If you have a Scope 1 number to defend, a QET sharpens the inputs feeding that number. It does not erase it.

Read why double counting is the central integrity problem

A QET moves through four stages on the EarnDLT registry, all anchored on-chain:

• Mint. The producer (and its measurement partner where applicable) submits primary data into EarnDLT. An accredited third-party verifier reviews the data to ISO 14064-3 reasonable assurance and signs off. Only after sign-off is the QET issued — single mint, methodology-versioned, verifier-stamped.
• Discover. Buyers search the Marketplace by attribute: geography, basin, carbon intensity, MRV tier, methodology version, and producer-carried grades.
• Acquire. Buyers acquire QETs via on-chain transfer. The transfer is recorded on the Hedera ledger and the token lands in the buyer's wallet.
• Retire. The buyer retires the QET to anchor a specific claim — for a reporting period, a delivery location, or a disclosure line. Retirement is irrevocable on-chain. A retired token cannot be transferred, double-used, or double-claimed.

The retirement record is the artifact your auditor wants. It links a specific QET — and therefore a specific verified physical unit of fuel or electricity, with all its attributes and methodology lineage — to the disclosed number that depends on it.

How minting works

How discovery works

How acquisition works

How retirement works

A QET is designed to feed the frameworks reporters already use — not to replace them. Greentruth publishes framework-aligned exports out of the same underlying token, including:

• GHG Protocol Scope 3 Category 3 (Fuel- and Energy-Related Activities), via QET-NG and QET-RNG attestations
• GHG Protocol Scope 2 Quality Criteria, via QET-ELEC retirements
• SBTi Corporate Net-Zero Standard, including the CNZS V1.3 criteria most relevant to fuel-attribute claims
• The Climate Registry General Reporting Protocol, with QET-RNG mapped to GRP §D-7, §D-15, and §B-7
• ISO 14064-3 reasonable assurance and ISO 14067 product carbon footprint
• CSRD ESRS E1 and IFRS S2 machine-readable disclosure paths

The same approach extends to emerging public Energy Attribute Certificate frameworks — for example, the CCS-EAC and T-EAC frameworks that major corporate procurement programs have published — as illustrative reference points for what a credible attribute certificate is expected to carry. The principle is the same in all cases: the QET is the source-of-truth; the framework export is a view on it.

How QETs align to reporting frameworks

Greentruth issues four token types across the energy stack:

• QET-NG — Natural gas. One MMBtu, multi-pollutant CI in kgCO₂e/MMBtu, US framework anchors NGSI v2.0, OGCI Reporting Framework, and ONE Future v6.2023; OGMP 2.0 + EEMDL Protocol apply within the EU Methane Regulation compliance extension.
• QET-RNG — Renewable natural gas thermal certificates. One MMBtu of RNG thermal energy with verified CI in kgCO₂e/MMBtu, well-to-pipeline-injection scope (combustion is out of scope per methodology).
• QET-CCS — Carbon capture and storage extension. Structured to satisfy public CCS Energy Attribute Certificate frameworks emerging in the market.
• QET-ELEC — Electricity attribute extension. Structured to satisfy public T-EAC frameworks, with EnergyTag-compatible hourly matching for 24/7 carbon-free electricity strategies.

Each type runs on the same registry, the same retirement architecture, and the same methodology-versioned schema. Each carries the attributes its market needs.

QET-NG · QET-RNG · QET-CCS · QET-ELEC

Migrate from a legacy registry