T-VER methodologies specify the applicable project activities, project conditions, and methodologies for calculating greenhouse gas (GHG) emission reductions or removals for Premium T-VER projects, in accordance with the project types specified by the Board of Directors of TGO, as recommended by the Subcommittee on the Consideration of GHG Mitigation Projects and Activities.

The development of T-VER methodologies must adhere to six fundamental principles for assessing greenhouse gas (GHG) emission sources, proposing GHG emission reduction quantification methods, and defining monitoring approaches to ensure the trust in carbon credits under the Premium T-VER. These principles include:

1) Relevance refers to the selection of GHG emission sources, carbon sinks, data collection methods, measurement approaches, and calculation methodologies that must align with the requirements of the target stakeholders. The collected or estimated amount of GHG emission reduction should accurately reflect the emission reduction occurring within or related to the project boundary.

2) Completeness refers to the collected or assessed amount of GHG emission must account for GHG emissions from all activities occurring within the project boundary or related to the project. All relevant data related to GHG reduction must be gathered, including any information necessary to support the criteria and processes in a comprehensive manner.

3) Consistency refers to the data collection and GHG emission reduction quantification methods must follow the same principles and approaches throughout the methodology.

4) Accuracy refers to the methodologies for GHG emission data collection and quantification that must be scientifically robust, reliable, and widely accepted.

5) Transparency refers to the relevant project information must be disclosed, and the collection or calculation of GHG emission reductions must be sufficient, appropriate, and verifiable.

6) Conservativeness refers to the assumptions, figures, and processes that must be applied in a manner that ensures the estimated GHG emission reductions from the project are not overestimated beyond actual reductions achieved.

In addition, the development of T-VER methodologies for the Premium T-VER must comply with the principles and requirements outlined in the Standard: Application of the requirements of Chapter V.B (Methodologies) for the development and assessment of Article 6.4 mechanism methodologies) under the Paris Agreement, published by the Supervisory Body established under the Paris Agreement.