CDM Pipeline

The current version of the CDM Pipeline gives an overview of the Clean Development Mechanism as of April 2024. It includes Project Activities (PAs), Programmes of Activities (PoAs) and the corresponding Component Project Activities (CPAs).  

For an accessible introduction to UNEP CCC’s work on both the CDM and Article 6 Pipeline, we produced a short video. Please find the result, which gives an overview and explains important components, here. 

CDM activities that are eligible and have requested transition to the A6.4 Mechanism 

The deadline for submitting requests has passed. In a new explainer video, we examine those activities that intend to transition using CDM methodologies and outline the next steps. 

 Video on the CDM Transition (08:30 minutes) – Slides: link 

As of 1 May 2024, transition requests were correctly submitted for 1,308 Project Activities (PA), 116 Programmes of Activities (PoA), and (together with these PoAs) 946 Component Project Activities (CPA) (see the figure below). While these numbers are close to the new potential maximum of CDM transitions, there may be additional activities for which re-submissions are possible after the first request did not meet procedural requirements. 

Of the potential reductions of around 1.5 billion tonnes of CO2e that eligible activities could generate after transition while using CDM methodologies, this could amount to more than 900 million tonnes (59%) 

For more details (such as submissions by host countries, regions, and activity types) refer to the sheet Analysis CDM Transition in the Article 6 Pipeline. The continuously updated list of requests including the link for stakeholder comments can be found here. 


In addition to detailed info on each of the activities, the focus of the analysis in the CDM Pipeline is: 1) which and how many CDM activities can transition to the new Article 6.4 mechanism without applying new methodologies and 2) which and how many Certified Emission Reductions (CERs) issued under the CDM until the end of 2020 can be used to fulfil Nationally Determined Contributions (NDCs) under the Paris Agreement. 

  • Article 6 eligible: registered or provisional PAs, PoAs and CPAs eligible for transition to the Article 6.4 mechanism of the Paris Agreement. The criterion is: crediting period active as of 1 January 2021. 
  • First NDC eligible: registered PAs and PoAs with certified emission reductions (CERs) eligible for compliance with first or first updated NDCs (most of which end by 2030). The criterion is: registered on or after 1 January 2013 

For more information, a comprehensive FAQ by the UNFCCC Secretariat gives an accessible overview. 


The graphs and tables below give an overview the CDM’s potential impact on arrangements under the Paris Agreement (i.e., NDCs and Article 6). For further analysis, the Excel database is freely available and the tables in the Analysis sheet can be easily adapted to the user’s needs. 

Analysis of the eligibility for Article 6 transition and CER use towards countries’ first NDCs. 

While there are significantly more registered Project Activities (7,866) than Programmes of Activities (364) and their associated Component Project Activities (2,827), the respective shares of how many of those are eligible for transitioning to Article 6 are similar (between 42 and 46%). 

The share of PoAs eligible for using CERs for the first NDC (38%) is higher than the corresponding share of PAs (9%), because PoAs generally have later registration dates.   

Table 1. Number of PAs, PoAs and CPAs (as of 2 January 2024) 



  • This is a theoretical exercise to estimate the projects that are eligible for the Article 6.4 mechanism. It represents the potential (maximum) number of PAs and PoAs (as of 2 January 2024). The same applies for the activities that are eligible for issuing CERs that can be used towards the first NDC. 
  • For PAs, the deadline for submitting a renewal request has expired. Therefore, there will be no additional registered CDM project activities that will qualify for transition to Article 6.4 mechanism (PAs that were registered at the beginning of 2021 but de-registered since then are now also included).  
  • The actual numbers of PAs, PoAs and CPAs that will transition to Article 6.4 remain uncertain.  
  • The deadline for project participants to submit a request for the transition was 31 December 2023 – though some re-submissions are possible, this is now largely fixed (see analysis in the A6 Pipeline). 
  • The deadline for the host country to approve the request is 31 December 2025.  
  • Most countries have not yet published criteria indicating which requests they would approve. 
  • Host Parties may decide to approve eligible CDM projects to transition to the Article 6.4 mechanism (for issuances after 2020), to use CERs (issued between 2013 and 2020) towards the first NDC, or none of the options.  
  • CERs that can be used towards first NDC fulfilment do not require Corresponding Adjustment. However, Article 6 credits when traded internationally for NDC fulfilment do.  


Table 2. Issuances from PAs and PoAs that are eligible for fulfilling first NDCs (during 2013 – 2020) in thousand CERs  

Updates in April: 

The CDM pipeline contains the following updates compared to the last version (March 27): 

  • New issuances since March 27: 1.5 million CERs (1.0 of which NDC-eligible) 
  • New voluntary cancellations since March 27: 2.8 million CERs