QET Discovery: Finding Verified Attributes by Geography, CI, and MRV Tier

QET discovery is the second stage of the marketplace lifecycle that runs Mint → Discover → Acquire → Retire. Buyers use Discovery to find Quantified Emissions Tokens whose attributes match what their reporting framework — and their procurement integrity story — actually require. This page explains what Discovery does, what attributes it searches against, and how a search becomes a retired claim.

QET discovery, in one paragraph. QET discovery is the buyer-side flow on Greentruth's Marketplace for locating tokens that match a buyer's attribute requirements: geography, basin, multi-pollutant carbon intensity, MRV tier, methodology version, producer-carried grades, and regulatory-program eligibility (California LCFS, EU Methane Regulation, GHG Protocol market-based method). The Discovery flow runs against the live EarnDLT registry, so the records a buyer searches over are the same records minted by producers and operators — single-source, verifier-stamped, retire-able.

What a QET is in the first place

QET discovery is the gateway between “I have a Scope 1, Scope 2, or Scope 3 Category 3 line to substantiate” and “I have a retired token anchoring that claim.” It is the buyer-side surface of the marketplace lifecycle — sitting between Minting (the producer-side issuance) and Acquisition (the transactional handoff).

Practically, QET discovery has three properties worth internalizing:

• It searches against verified records, not against listings. Every QET that surfaces is already minted, methodology-versioned, verifier-stamped, and on-chain on the EarnDLT registry. The buyer is not browsing intentions; the buyer is browsing certificates.
• It is attribute-first, not price-first. The order of the search reflects what a reporting team actually cares about: geography, CI, MRV tier, methodology version. Price surfaces inside that frame, not above it.
• The same flow handles every token type. QET-NG (natural gas), QET-RNG (renewable natural gas), QET-ELEC (electricity), and QET-CCS (CCS attributes) all expose the same attribute model, with token-specific attributes layered on.

The full marketplace lifecycle

How double counting is prevented

The attribute schema is what makes QET discovery something other than browsing a list of certificates. Every minted token carries the same baseline attribute set, plus token-specific attributes for its class.

Universal attributes on every 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.
• Multi-pollutant carbon intensity. Where applicable, CH₄, CO₂, and N₂O converted via IPCC AR5 GWP100 factors (CH₄ = 28, N₂O = 265). Not methane-only; the full pollutant set.
• Geography. Producing basin, operator, and (for transmission) the validated pipeline pathway across EarnDLT's 32,000-segment Lower-48 network model.
• MRV tier. Where the underlying data sits in the methodology's data hierarchy: site-specific primary → process-specific primary → peer-reviewed secondary → industry-average secondary.
• Methodology version. The exact methodology and reference dataset version used (including R&D GREET 2025 where applicable).
• Verifier of record. The accredited third-party verifier under ISO 14064-3 reasonable assurance.

Token-specific attributes:

• QET-NG / QET-RNG. Producer-carried third-party grades (where the producer carries them), biogenic carve-out (RNG only), pathway eligibility flags (LCFS, RED III, FuelEU Maritime forward-looking).
• QET-ELEC. Hourly granularity, grid, deliverability path, EnergyTag-compatible matching.
• QET-CCS. Project provenance, capture source, storage permanence classification, monitoring obligations.

The schema is what makes attribute-based discovery scale: a buyer can filter on the same six universal attributes across the QET family, then narrow within each token class on the attributes that matter for the specific reporting line.

How the pipeline pathway model resolves transmission

A search runs as a structured flow inside the Marketplace surface:

• Define the reporting claim. What scope line, what reporting period, what framework? (SB 253 Scope 3 Category 3; GHG Protocol Scope 2 market-based; SBTi-aligned Scope 1 fuel-substitution.) The reporting claim shapes which attributes matter.
• Filter on universal attributes. Geography, basin, multi-pollutant CI threshold, MRV tier minimum, methodology version, verifier-of-record list.
• Filter on token-specific attributes. For QET-NG: producer-carried grades, pathway. For QET-RNG: biogenic carve-out specifics, LCFS pathway eligibility. For QET-ELEC: hourly granularity, grid match. For QET-CCS: storage permanence classification.
• Save the search. Recurring procurement programs build watchlists that surface newly minted QETs matching the saved criteria.
• Inspect candidates. Open the certificate to see the full attribute set, methodology version pin, and verifier-of-record attestation under ISO 14064-3 reasonable assurance.
• Match to Acquire. Selected QETs flow into the Acquisition step with the attribute set the buyer searched on — no re-keying, no manual reconciliation.

The flow is identical for human buyers in the dashboard and for programmatic buyers via the Machine-Ready API.

Beyond the attribute schema, the search supports regulatory-eligibility filters that surface only the QETs structured for a specific program:

• California LCFS eligibility. For QET-RNG, the LCFS-eligible search surfaces tokens that run with the QET-LCFS extension — pathway-certifiable under CARB with the chain-of-custody record the verifier expects.
• EU Methane Regulation compliance. For QET-NG, the EU-compliance search surfaces tokens minted with the EU compliance extension (EEMDL Protocol reconciliation, OGMP 2.0 alignment, ISO 14064-3 reasonable assurance for Article 8).
• GHG Protocol market-based Scope 2. For QET-ELEC, the market-based eligibility filter surfaces tokens that satisfy the GHG Protocol Scope 2 Guidance's contractual-instrument quality criteria.
• SBTi-aligned procurement. Across the family, filters surface tokens whose methodology versioning aligns to the SBTi Corporate Net-Zero Standard version in force at the buyer's reporting cycle.

The point of these filters is to make the regulatory question the buyer's first filter, not the buyer's afterthought. A QET that surfaces under a regulatory-eligibility filter is ready to feed the corresponding disclosure on the day of retirement.

GHG Protocol Scope 2 Guidance

CARB Low Carbon Fuel Standard

The handoff matters because it preserves the buyer's audit trail. When a candidate QET surfaces and the buyer moves it forward, the system:

• Carries the full attribute set from the search into the Acquire step without re-keying.
• Records the search criteria that surfaced the candidate (so the audit trail shows what the buyer was looking for, not just what the buyer found).
• Preserves the methodology-version pin and verifier-of-record attestation the candidate carries — these are what the framework export at retirement will reconstruct against.
• Routes the candidate into the Acquisition flow, which writes the on-chain transfer record once payment settles.

For programmatic procurement via Machine-Ready, the same handoff happens via API — the search returns matching QETs, the buyer's platform routes them into Acquisition, and the lifecycle continues without manual reconciliation. The downstream Retirement step writes the irrevocable on-chain claim record that anchors the disclosure.

How GasTrace pulls QETs into downstream EAC workflows