Verra VM0044 Permanence and Quantification
Parent hub: Verra VM0044
Eligibility rules: Verra VM0044 Methodology and Eligibility
Science context: Permanence Science for Credits · Permanence · models soil GHG from biochar · estimates soil C stock change from biochar
Compare: Isometric Permanence Pathways 200y and 1000y · Puro CORC200+ · Verra vs Isometric vs Puro
This chapter covers how much carbon is credited and over what horizon under VM0044. Numbers below are taken from the public VM0044 v1.1 PDF unless labeled otherwise. Active program version is v1.2 (methodology page) — confirm Table 3 / equations unchanged in the live v1.2 PDF before locking a project model.
Horizon claim
| Item | VM0044 (v1.1 PDF) | Peer contrast |
|---|---|---|
| Crediting permanence window | 100 years | Puro CORC200+ (several centuries); Isometric 200y or 1000y |
| Framing | “100-year permanence value … based on 100-year global warming potential horizon” | Puro CORC200+ · Isometric Permanence Pathways 200y and 1000y |
Utilization must occur within one year of production so pre-application decay does not undermine the 100-year factor (v1.1 applicability).
Core high-tech stored-carbon equation
For Option P.1 — High Technology Production Facility (v1.1 §8.2.2.1):
[ CC_{t,k,y} = \sum_p \left( M_{t,k,p,y} \times FC_{p,t,p} \times PR_{de,k} \right) ]
Then organic carbon is converted to CO₂e with the stoichiometric factor 44/12.
| Symbol | Meaning |
|---|---|
| (CC_{t,k,y}) | Organic C (dry) for biochar type (t), application (k), year (y) (tonnes) |
| (M_{t,k,p,y}) | Dry mass of that biochar from facility (p) |
| (FC_{p,t,p}) | Organic carbon content (dry weight percent) — lab analysis for high-tech |
| (PR_{de,k}) | Permanence / decay adjustment factor for application type (k) |
Lab methods: latest IBI Biochar Testing Guidelines or EBC Production Guidelines or other internationally/nationally accredited standards (v1.1).
Net removals also subtract project emissions at production (pre-treatment, conversion, auxiliary energy) and account for leakage / transport per methodology tools — see Verra VM0044 Project Cycle and MRV and MRV Stack.
Table 3 — default (PR_{de,k}) for soil
Table 3 (v1.1) provides default permanence adjustment factors drawn from IPCC (2019) Table 4AP.2 and models soil GHG from biochar framing, keyed to production temperature (T_{prod}):
| Temperature class | Default (PR_{de,k}) |
|---|---|
| High temperature pyrolysis / gasification (> 600 °C) | 0.89 |
| Medium temperature pyrolysis (450 – 600 °C) | 0.80 |
| Low temperature (350 – 450 °C) | 0.65 |
Sources: VM0044 v1.1 PDF; IPCC 2019 App. 4 PDF; Woolf et al. 2021.
Important clarification — Table 3 vs H:Corg
| Concept | Role in VM0044 v1.1 |
|---|---|
| Table 3 (PR_{de,k}) | Temperature-class default fraction of organic C treated as remaining over 100 years |
| H:Corg ≤ 0.7 | Soil eligibility gate (aromaticity / quality), not the Table 3 lookup key |
Do not conflate with Isometric’s continuous H/Corg + soil-temperature decay function or CSI’s H/Corg ≤ 0.40 GPC split. Science map: Permanence Science for Credits.
Non-soil (PR_{de,k})
If scientifically robust permanence information for the non-soil product is unavailable, use the soil Table 3 default for the production temperature class (v1.1).
Project proponents may propose an alternate (PR_{de,k}) with evidence meeting VCS Methodology Requirements default-factor rules (peer-reviewed). If literature conflicts, adopt the lower value. White papers / non-peer-reviewed research are not accepted (v1.1).
Only high-tech biochar qualifies for non-soil pathways; biochar must be ≥ 50% C dry weight (Verra VM0044 Methodology and Eligibility).
Low-technology quantification path
Facilities that fail the four-condition high-tech definition use the low-tech option (v1.1):
- Organic carbon content may rely on IPCC default tables/figures (e.g., Table 4 / Figure 4Ap.1 themes in methodology) rather than full batch lab (FC)
- CH₄ / soot minimization must still be demonstrated (convection-zone kiln examples discussed in §8 narrative)
- Generally less flexible / more conservative than high-tech lab path
High-tech definition (recap): GHG recovery/combustion; ≥70% heat use; pollution controls; measured temperature — full text in Verra VM0044 Methodology and Eligibility.
Project emissions at production (high-tech sketch)
[ PE_{PS,p,y} = (PE_{D,p,y} + PE_{P,p,y} + PE_{C,p,y}) \times \frac{\sum_t\sum_k M_{t,k,p,y}}{M_{p,y}} ]
| Term | Meaning (v1.1) |
|---|---|
| (PE_D) | Pre-treatment of waste biomass (drying, pelletizing, etc.) |
| (PE_P) | Conversion / pyrolysis-related accounted emissions |
| (PE_C) | Auxiliary energy for pyrolysis |
Biogenic CO₂ from biomass is treated within the carbon-cycle framing of the methodology; CH₄ and soot remain material because of higher GWP (methodology narrative citing Amonette et al. 2021). High-tech condition (a) (combust/recover pyrolytic gases) underpins de minimis treatment of some direct process emission categories — see PDF footnotes.
Full boundary GHG table: v1.1 Table 2 (confirm in PDF).
H:Corg eligibility vs other programs
| Program | Chemistry gate | Permanence model |
|---|---|---|
| Verra VM0044 | Soil H:Corg ≤ 0.7 | Table 3 temperature defaults @ 100y |
| Isometric soil | H/Corg < 0.5, O/Corg < 0.2 | Woolf-style 200y function or Ro≥2% 1000y |
| Puro Ed. 2025 | H/Corg domain in power model (see method) | CORC200+ power decay + 80% CI |
| CSI C-Sink 3.3 | H/Corg ≤0.40 → 75% GPC; Ro≥3.8% or HyPy≥90% → 90% GPC | GPC / SPC pools |
Sources: v1.1 PDF; Isometric soil module; Puro Biochar Methodology Edition 2025; CSI Global Biochar C-Sink.
What VM0044 does not do (as of v1.x)
- Does not issue millennial inertinite / Ro credits like Isometric Option 2 or CSI upper GPC
- Does not use soil temperature as a continuous decay input in Table 3 defaults
- Does not (yet) make H/Corg the Table 3 lookup key — though v2.0 consultation proposes enhanced H/Corg & moisture monitoring (consultation)
Worked intuition (illustrative only)
Suppose high-tech biochar, dry mass 1.0 t, lab organic C = 80%, produced at 650 °C → (PR_{de}=0.89):
[ CC = 1.0 \times 0.80 \times 0.89 = 0.712\ \text{t C} ] [ CO_2e\ \text{before PE/leakage} \approx 0.712 \times 44/12 \approx 2.61\ \text{tCO}_2e ]
Then subtract project emissions, leakage, and apply any VCS buffer rules. Do not use this as a credit quote — it ignores PE, transport, application evidence, and verification findings.
Science anchors
- estimates soil C stock change from biochar — temperature-class (F_{perm}) inventory guidance
- models soil GHG from biochar — DOI
- inertinite permanence benchmark — DOI (used by Isometric/CSI, not VM0044 Table 3)
- Permanence Science for Credits · Permanence · Consensus vs Debates
Primary links
- VM0044 v1.1 PDF (Table 3)
- VM0044 v1.2 methodology page
- IPCC 2019 App. 4
- Woolf et al. 2021
- v2.0 consultation