The Paris Agreement Crediting Mechanism now has an adopted methodology for certain grid-connected renewable-power projects. A6.4-AMM-003 covers qualifying greenfield hydro, wind, solar photovoltaic, solar thermal and geothermal plants, including narrowly defined co-located battery storage. It does not turn ordinary renewable generation into Article 6.4 units by default.
For a buyer or developer, the practical question is not simply, "Does the technology appear on the list?" The question is whether the activity can pass six separate gates from project configuration through to registry delivery. Failure at any one can reduce the expected volume, delay it or prevent issuance and use altogether. For a primer on how Article 6.2 and Article 6.4 differ as cooperation routes, see our companion guide.
What the Supervisory Body adopted on 30 July 2026
At its meeting in Bonn from 27 to 30 July 2026, the Article 6.4 Supervisory Body adopted A6.4-AMM-003, Electricity generation from renewable sources connected to an electricity system. It also adopted version 03.0 of the Article 6.4 mechanism registry procedure.
These are real implementation advances, but they do different jobs. The methodology defines which activities can apply and how emission reductions are calculated. The registry procedure governs accounts, unit records, transfers, retirement and cancellation. Host Party approval and authorisation, validation, registration, monitoring, verification and issuance remain separate parts of the mechanism.
The distinction matters in procurement. A methodology-compatible project is not the same thing as a registered activity. A registered activity is not a guarantee of a particular issued volume. An issued Article 6.4 emission reduction (A6.4ER) is not necessarily authorised for an international use. Contract language should reflect each step.
The six-gate screen
| Gate | Decision question | Evidence to request before commitment | Main commercial risk |
|---|---|---|---|
| 1. Configuration | Does the plant and any storage meet the methodology's scope? | Site design, commissioning plan, grid connection, technology and metering diagram | Ineligibility or redesign |
| 2. Additionality | Can all required analyses conclude positively? | Legal register, support-scheme record, financial model and common-practice assessment | Registration failure or crediting cessation |
| 3. Quantification | How do baseline adjustment, activity emissions and leakage affect volume? | Ex-ante calculation workbook, uncertainty record and technology-specific inputs | Overstated forward volume |
| 4. Attribute integrity | Are EACs, other credits and domestic scheme effects excluded or cancelled correctly? | Attribute issuance and cancellation controls; domestic scheme analysis | Double counting or conflicting claims |
| 5. Host Party status | Has the activity obtained the decisions needed for registration and the intended use? | Current host Party statements, approval and authorisation documents | Unit-use mismatch or authorisation delay |
| 6. Registry delivery | Can each party hold, transfer, retire or cancel the relevant unit type? | Account authority, representatives, KYC readiness, fees and delivery instructions | Settlement or use failure |
This framework is a diligence sequence, not a prediction that a project will register or issue units.
Gate 1: The methodology is narrower than "renewable energy"
A6.4-AMM-003 version 01.0 applies to a greenfield power plant that feeds all net electricity into an electricity system. It lists five eligible technologies: hydropower, wind, solar photovoltaic, solar thermal and geothermal. It does not cover capacity additions, retrofits, rehabilitation or replacement at an existing plant in this version.
Battery energy storage systems are permitted only when they sit at the same site, charge solely from the Article 6.4 renewable plant and are installed before the activity's electricity metering point. Battery production, transport and installation emissions are treated as leakage in the calculation. A standalone battery, a grid-charged battery or a loosely connected hybrid should not be assumed eligible under this route.
Hydropower has further configuration tests. Project teams should work from the exact methodology rather than a technology label, especially where reservoirs, existing infrastructure or storage are involved.
For developers, the immediate task is a configuration memo tied to numbered methodology provisions. For buyers, the term sheet should identify the methodology version and make registration under that version, or an agreed successor, a condition rather than a representation of current fact.
Gate 2: Four additionality analyses must work together
The adopted methodology requires regulatory, lock-in, investment and common-practice analyses. All four must conclude positively, although the methodology treats lock-in differently by technology. Geothermal projects require a lock-in assessment; qualifying hydro, solar and wind plants are not deemed to create lock-in risk under the methodology's applicability conditions.
The regulatory analysis deserves early legal attention. It tests applicable host-country requirements and whether the activity is driven by a law, obligation, support scheme or penalty scheme aimed at a quantitative outcome. The methodology specifically addresses competitive bidding processes such as renewable-electricity auctions. If the regulatory conditions are not satisfied, A6.4ERs cannot be claimed. The test repeats for each monitoring period, and crediting stops when a new relevant legal requirement becomes applicable. The adopted methodology sets out the complete test in paragraphs 28 to 30.
That creates two underwriting risks. First, an attractive renewable project may be financially additional yet fail the regulatory test because of how national support or procurement rules apply. Second, a project that qualifies at registration may lose future crediting when the legal position changes.
Developers should maintain a dated legal and policy register, including auction awards, tariffs, tax benefits, renewable obligations, capacity targets and site-specific permits. Buyers should require notification of any change that could affect regulatory surplus and a volume-adjustment mechanism if crediting ceases.
Gate 3: Eligible generation is not the same as credited volume
The methodology calculates reductions from a downward-adjusted electricity baseline, then subtracts activity emissions and leakage. The initial downward adjustment uses the more conservative of an uncertainty-based value and the methodology's minimum calculation. The adjustment then increases by 0.01 per year under version 01.0. This means a forecast based only on megawatt-hours multiplied by a grid factor is not a bankable Article 6.4 volume forecast.
Technology-specific deductions also matter. Co-located batteries bring upstream leakage. Wind projects may need to deduct generation lost at other wind plants through wake effects unless an exception applies. Geothermal, solar thermal and hydro configurations have their own activity-emission or applicability provisions.
A buyer should therefore ask for three views of supply:
- Gross renewable generation.
- Unadjusted baseline emission reductions.
- Expected A6.4 emission reductions after downward adjustment, activity emissions, leakage and a delivery contingency.
Only the third belongs in an offtake delivery model, and even that remains an estimate until monitoring, verification and issuance. A quantitative reviewer should reproduce the calculation and stress the grid factor, uncertainty, legal-change date, operating performance and methodology revisions.
Gate 4: EACs and carbon units cannot tell conflicting stories
Renewable electricity can carry more than one environmental instrument. The adopted methodology directly addresses this risk. Each monitoring report must show that the electricity, associated mitigation outcomes and environmental attributes are not also claimed under another crediting or certification scheme. If renewable energy certificates or similar attributes are issued, the methodology provides for administrative cancellation without an associated claim as one route to prevent double counting.
The methodology also requires evidence that the reported reductions do not overlap with mandatory domestic mitigation schemes, or that measures prevent the same impact from reducing covered entities' obligations while also supporting A6.4 issuance.
This is not a minor registry housekeeping point. An EAC contract, green tariff, power purchase agreement, carbon offtake and host-country accounting decision can all allocate different rights. The project data room should map, for every megawatt-hour:
- whether an EAC or other attribute can be issued;
- who controls issuance and cancellation;
- whether any party makes a renewable-electricity or emissions claim;
- whether a domestic compliance scheme counts the same effect; and
- which evidence enters the Article 6.4 monitoring report.
Buyers should reject vague promises that attributes will be "managed appropriately". The contract should specify the instrument, registry, serial evidence, cancellation purpose, beneficiary, claim restriction and remedy for a conflicting use.
Gate 5: Methodology fit does not replace host Party decisions
Article 6.4 is Party-supervised. A project must move through the mechanism's activity cycle, including validation and a formal registration request. The host Party's role and participation status must be checked against current UNFCCC records and the intended unit use.
The intended use is especially important. Article 6.4ERs may exist with different authorisation status. The registry procedure calls an A6.4ER authorised by the host Party for an NDC and/or other international mitigation purpose an AER. It calls an A6.4ER without that authorisation status an MCU. The two are not interchangeable for every buyer purpose. For background on how authorisation, transfer and use work for internationally transferred mitigation outcomes more broadly, see our ITMO guide.
Before pricing a forward purchase, define the required deliverable precisely: methodology, activity, monitoring period, unit type, authorisation, authorised use, corresponding-adjustment status, registry account and cancellation or retirement destination. "Article 6.4 credit" is too broad for a delivery clause.
Legal review is required for the host-country approval, authorisation and use language. The article does not determine whether a unit is eligible for a particular compliance programme, claim or jurisdiction.
Gate 6: Registry permissions shape settlement
Registry procedure version 03.0 establishes account types for holding, retirement and cancellation, among other functions. An authorised entity must pass applicable identity checks, pay applicable fees and designate at least two authorised representatives. Each holding account is associated with one authorising Party, although an entity may have separate accounts associated with different Parties.
Those rules should enter transaction planning before delivery day. The buyer, seller, custodian and authorising Party need compatible permissions and clear instructions for the intended use. Transfers are recorded in Coordinated Universal Time, and the procedure states that registry transfers are final.
The procedure is also unfinished in identified areas. The Supervisory Body said it would be revised further and requested work on post-issuance authorisation and first transfer from a Party that is not the host Party. The adopted procedure itself marks post-issuance authorisation and changes of authorisation for enhancement in later iterations. The meeting report records these open items in paragraph 24.
A forward contract should therefore allocate change-in-procedure risk. At minimum, it should address account-opening delay, authorisation that differs from the required use, a changed first-transfer route, failure to pay registry fees, unavailable delivery instructions and a unit that arrives with the wrong status.
Evidence schedule for a project or offtake
The most efficient diligence process collects evidence in the order a project can fail, starting with the project documentation and methodology application.
| Stage | Minimum evidence | Decision |
|---|---|---|
| Concept screen | Configuration memo, host-country screen, methodology version | Proceed to development or stop |
| Term sheet | Additionality pre-assessment, policy register, ex-ante volume model, attribute map | Set conditions and price basis |
| Before registration | Validated project documentation, host Party documents, final financial and common-practice analyses | Confirm eligibility case |
| Before each delivery | Monitoring and verification status, issuance record, authorisation and first-transfer flags, registry instructions | Accept, defer or reject delivery |
| Before claim or use | Cancellation or retirement evidence and programme-specific eligibility review | Approve the intended use |
This order avoids spending months negotiating price for a project that cannot pass a threshold eligibility or authorisation test.
What buyers and developers should do now
Developers with prospective greenfield renewable plants should run the six-gate screen before treating Article 6.4 revenue as committed project finance. The screen should be refreshed when the host-country legal framework changes, the methodology is revised or registry implementation guidance develops.
Buyers should make offers conditional on documentary milestones rather than on the project description alone. Volume should be defined after the methodology's deductions, not from nameplate capacity or gross generation. The EAC and domestic-scheme analysis should sit beside the carbon calculation, not in a separate workstream. For the broader review process across legal, financial and operational risk, see our guide to carbon project due diligence.
The 30 July decisions create a credible route for qualifying renewable-power activities. They do not remove project, country, accounting or settlement risk. That is precisely why the route is now worth diligencing in detail.
Organisations evaluating a renewable-power activity or forward purchase can request a focused Article 6 eligibility, authorisation and delivery assessment from Sentinel Earth before committing to volume or claim terms.
This article is informational and does not constitute legal, financial, investment, accounting or trading advice. Requirements and registry procedures can change. Verify the current UNFCCC documents, host-country position and intended-use rules for each transaction.
Sources
- Article 6.4 Supervisory Body, meeting report for 27 to 30 July 2026, accessed 11 August 2026.
- A6.4-AMM-003: Electricity generation from renewable sources connected to an electricity system, version 01.0, accessed 11 August 2026.
- Procedure: Article 6.4 mechanism registry, version 03.0, accessed 11 August 2026.
- UNFCCC registration overview for the Article 6.4 mechanism, accessed 11 August 2026.
