ClearBlue Knowledge Base

ICVCM Approves Adipic Acid and Additional Cookstove Methodologies

Written by Nico Curtis | Jun 3, 2025 11:12:39 PM

The Integrity Council for the Voluntary Carbon Market (ICVCM) announced a new round of methodology approvals under its Core Carbon Principles (CCP) label. Three methodologies, two Adipic Acid Production Protocols and one Clean Cookstove were determined to meet the ICVCM’s high-integrity standards, subject to certain conditions. The ICVCM also announced that the carbon crediting program Ecosystem Restoration Standard (ERS) has achieved CCP-Eligible status following a successful program-level assessment.

Additional Clean Cookstoves Methodology Approval

As part of its latest CCP label decisions, the ICVCM approved Gold Standard’s Reduced Emissions from Cooking and Heating – Technologies and Practices to Displace Decentralized Thermal Energy Consumption (TPDDTEC) version 2-3.1, conditioned on the satisfaction of specific criteria.

On 7 March 2025, the ICVCM announced the approval of three clean cookstove methodologies, including Gold Standard’s TPDDTEC Version 4.0. However, the ICVCM clarified that methodologies must comply with three key requirements to qualify for the CCP label:

  • The fraction of non-renewable biomass (fNRB) must be derived using the Modeling Fuelwood Savings Scenario (MoFuSS) model or, the Clean Development Mechanism (CDM) default of 0.3 may be applied for a limited period.
  • Fuel consumption must be determined either by using a Kitchen Performance Test (KPT) or Controlled Cooking Test (CCT) or using methodology default values with cross-checks on fuel savings.
  • For projects using charcoal, a direct charcoal emission factor or a wood-to-charcoal conversion factor of 4:1 must be used.

The approval of TPDDTEC Version 2-3.1 is conditional upon meeting these three core requirements, ensuring consistency with other approved clean cookstove methodologies. In addition, four methodology-specific conditions must be met for TPDDTEC Version 2-3.1 to receive the CCP label, aligning it more closely with Version 4.0:

  • A reassessment of baseline emissions has been conducted at least once within the five years immediately preceding the start of an issued monitoring period
  • No emission reductions are claimed from cookstoves that are aged beyond their technical life – unless replaced or retrofitted with a performance guarantee
  • Project emissions from transport of fuels is either proven to be negligible (<5%), or accounted for in emission reduction calculations
  • Emission reductions are excluded or discounted where the project is found to displace or operate alongside another mitigation activity

To date, approximately 51 million credits have been issued and 30 million retired under TPDDTEC Version 2-3.1. However, it is estimated that none of these credits currently meet all required conditions, making them ineligible for CCP labeling. Project developers may update their accounting to comply with CCP requirements, making future issuances eligible.

This decision marks the completion of the ICVCM’s review of existing clean cookstove methodologies, a significant milestone for the voluntary carbon market.

Approval of Apidic Acid Methodologies

In parallel, the ICVCM approved the following two methodologies for adipic acid production:

Adipic acid production releases nitrous oxide (N₂O), a greenhouse gas 298 times more potent than carbon dioxide and a leading contributor to ozone layer depletion, with China and the United States being the largest producers. Abatement technologies can mitigate these emissions by converting N₂O into nitrogen and oxygen, allowing facilities to generate carbon credits from the avoided emissions.

To address leakage risk, credits issued under the U.S. Adipic Acid Production Protocol require that production levels not exceed the facility’s Title V permit limit. (Title V is a U.S. regulatory framework requiring operating permits for emissions sources exceeding 100KtCO₂e.)

Approximately 17.3 million credits have been issued under these methodologies, all originating from the Phlogiston Phase I project.

Approval of Carbon Crediting Program Ecosystem Restoration Standard (ERS)

The ICVCM also announced that the Ecosystem Restoration Standard (ERS) is now CCP-Eligible, confirming it meets the Integrity Council’s criteria for governance, transparency, tracking, and independent third-party validation.

With this program-level approval, the ERS’s Afforestation, Reforestation, and Revegetation (ARR) methodology advances to the ICVCM’s methodology assessment pipeline.

Founded in 2020 and headquartered in Paris, the ERS program was developed to address key challenges in the voluntary carbon market, supporting climate action, biodiversity protection, and livelihood improvement. It focuses on certifying ecosystem restoration projects through its ARR methodology.

More information on the assessment status for the CCP program can be found here. Please reach out if you would like to discuss this development and the impact of CCP credits.