The No-Self-Reporting Principle
Conventional carbon credit verification relies on operator-submitted data. Projects file monitoring reports; validation/verification bodies audit what operators claim; registries issue credits based on the audited operator submissions. The operator sits in the middle of the chain of custody for their own credits.
Karbera operates differently. Every Karbera-verified credit is grounded in data already being recorded by parties other than the operator — government-published grid metering (ONS Brazil), regulatory plant registries (ANEEL SIGA), utility-issued documents, and hardware-attested device readings. Karbera reads what's already being recorded; the operator doesn't have to assemble or submit anything. The verification runs on the data, not on the operator.
This is the proof, not the pitch. It is what makes the rest of the engine possible.
This principle is foundational to both Karbera (the verification methodology) and CRIOS (the issuance platform that accepts only methodologies operating under it).
Earlier methodology versions remain in effect for operators where v3.2 schema extensions don't apply (e.g., v3.1 for MMGD operators without per-installation ownership data). Each operator surfaces its own active version.
Overview
Karbera computes avoided emissions at hourly resolution using verified ONS dispatch. Verification depth varies by asset class: utility-scale plants are individually grid-verified; MMGD operators are reconciled against EPE PDGD aggregates where possible, modeled where not. Every per-row figure carries its verification tier so reviewers can audit the mechanism, not just the number.
Four-tier verification taxonomy
Every plant's hourly generation is independently verified at the generation-side meter via ONS dispatch (geracao_usina_2_ho / geracao_termica_despacho_2_ho) — the canonical metered values used by ANEEL/CCEE for settlement. Avoided emissions are credited net of operator beneficial-ownership share (v3.2). Operators served: Engie Brasil Energia, CEMIG GT.
Operator's aggregate portfolio matches EPE PDGD cell totals within ±15% tolerance. Per-installation figures are methodology allocations of the verified aggregate — not independently metered per-plant. The honest framing: best-available verification for Class A MMGD operators.
Capacity known from Sistema GD registry; production modeled from regional capacity factors and hourly profiles. No reconciliation anchor. Default when EPE PDGD fixtures are absent or cell reconciliation falls outside tolerance. Stays on v3.1 until per-installation ownership data is available.
Tier 2 — bill-OCR (utility-issued documents are third-party to the operator). Tier 3 — inverter API direct-read (manufacturer-side telemetry). Tier 4 — hardware-attested signed device readings. All tiers operate under the No-Self-Reporting Principle: the operator authorises access; the data originates outside the operator. Ingestion is Phase 4 work.
Methodology integrity rule
Any displayed numeric figure that an external party could independently verify uses the recognizable form (operator's published nameplate, not internal methodological transformations). Derived values are shown alongside, not in place of, canonical values. This governs capacity (DC nameplate primary, AC equivalent alongside), coverage % (basis explicit), emission factors (sources cited), and grid AEF (Karbera-computed value cross-checked against MCTI's official monthly factors).
Every per-row numeric figure is traceable to its verification mechanism, and the mechanism is visible to the user. The four-tier taxonomy above is the buyer-facing form of this principle.
Data sources
Plant registry — every generation asset connected to the Brazilian grid, with capacity, technology, owner, location.
Verified hourly generation by plant, published by the Brazilian grid operator.
Verified thermal dispatch by plant and fuel type, used to compute hourly grid AEF.
Emission factors
| Fuel / source | tCO₂/MWh | Citation |
|---|---|---|
| Natural gas combined cycle | 0.40 | IPCC AR6, 50%-efficient CCGT lifecycle |
| Natural gas simple cycle | 0.55 | IPCC AR6 |
| Coal | 0.95 | IPCC AR6, average for Brazilian fleet |
| Oil / Diesel | 0.78 | IPCC AR6 |
| Biomass | 0.00 | IPCC standard convention; see limitations |
| Nuclear | 0.00 | IPCC standard convention |
| Renewable (hydro/wind/solar/ocean) | 0.00 | IPCC standard convention |
Calculation walkthrough
Worked example for one hour of one plant.
Limitations (honest disclosure)
- AEF only today. Karbera currently computes the Average Emission Factor (AEF) of the hourly grid mix. MEF (Marginal Emission Factor) is on the methodology roadmap — in active development, not shipped.
- Biomass treatment. Biomass is treated as zero-emission per IPCC convention. This assumes biomass is part of the short-term carbon cycle, which is debated in academic literature. Future versions may apply biomass-specific factors.
- Coverage. Currently restricted to plants individually tracked in ONS dispatch data. Plants in MMGD (Micro/Minigeração Distribuída) classifications are aggregated and not individually verifiable from public data alone. Operators may provide additional data to extend coverage.
- Losses. Grid emission factors do not yet account for transmission losses or auxiliary consumption at thermal plants. Both refinements are on the roadmap.
Scientific references
Karbera methodology is calibrated to first-principles scientific authorities and Brazilian regulatory data — not to commercial registry standards.
- UNFCCC CDM Tool 07 Methodological tool for the calculation of the emission factor for an electricity system.
- IPCC AR6 Working Group III Mitigation of Climate Change — GWP values and lifecycle emission factors for fossil generation.
- World Bank Carbon Pricing Dashboard Reference benchmark for global carbon price ranges across compliance and voluntary markets.
- ONS Brazil — Geração por Usina em Base Horária Hourly dispatch data for every grid-connected plant in the SIN.
- EPE Brazil Empresa de Pesquisa Energética — thermal fuel emission factors and PDGD distributed-generation aggregates.
- MCTI Brazil Ministério da Ciência, Tecnologia e Inovações — Operating Margin factors used as comparative reference, not as Karbera's primary calculation.
Version history
- v3.2current — Adds beneficial-ownership-share crediting (JV-aware netting) on top of v3.1's four-tier taxonomy. Active for utility-scale operators (Engie, CEMIG GT) where ownership data is available.
- v3.1in service for MMGD — Four-tier verification taxonomy. MMGD via Class A operators (aggregate-verified) and Class B/C disclosure framing. Remains current for MMGD operators pending per-installation ownership data.
- v3.0deprecated — Hourly AEF for utility-scale only.
- v2.0deprecated — Annual average emission factor. No longer issued.
- v1.0deprecated — Pilot-only static factor.