Addressing the risk of double counting emission reductions under the UNFCCC

The paper identifies four types of double counting—double issuance, double claiming, double use, and double purpose—and argues that preventing these is essential for the integrity of international carbon markets. It recommends a 'net flows' accounting approach to ensure full fungibility of units and the international linking of emissions trading schemes. To prevent double issuance, the authors suggest a combination of entity attestations, host country approval, and a centralized UNFCCC information platform. The document emphasizes that globally unique serial numbers containing detailed metadata on mechanism, country, vintage, and scope are critical for effective international oversight.

• Double counting is categorized into four distinct forms: double issuance (multiple units for one reduction), double claiming (reductions counted by both host and buyer countries), double use (one unit used twice for pledges), and double purpose (units used for mitigation and financial/technology pledges).
• Double issuance often occurs when mechanisms issue units for indirect emissions, creating ownership ambiguity where multiple entities (e.g., producers and consumers of biofuels) may claim the same reduction.
• International trade in electricity, fuels, and technologies can lead to double claiming if a mitigation action in one country reduces emissions in another country that also has a mitigation pledge.
• The authors recommend 'Approach A: Accounting for net flows of units' as the most logical method for a post-2020 regime because it supports the international linking of emissions trading schemes (ETS) and ensures full fungibility of units.
• To prevent double issuance, the paper recommends a multi-layered approach including mandatory attestations by entities, host country approval for all credited activities, and the establishment of a centralized UNFCCC information platform.
• To avoid double claiming via indirect emissions, the authors propose that baseline emissions occurring in a country or sector with a mitigation pledge should not be accounted for in the calculation of emission reductions.
• Effective international oversight requires that every unit possesses a globally unique serial number containing specific metadata: the mechanism, country (both action and reduction location), vintage, scope, credited activity, and permanence.
• The authors argue against 'double purpose' accounting, stating that emission reductions used to attain a buyer's mitigation pledge should not also be counted toward financial or technology pledges.

APA

Schneider, L., Kollmuss, A., & Lazarus, M. (2014). Addressing the risk of double counting emission reductions under the UNFCCC. Stockholm Environment Institute. https://www.sei.org/mediamanager/documents/Publications/Climate/SEI-WP-2014-02-Double-counting-risks-UNFCCC.pdf

Chicago

Schneider, Lambert, Anja Kollmuss, and Michael Lazarus. Addressing the risk of double counting emission reductions under the UNFCCC. Stockholm Environment Institute, 2014. https://www.sei.org/mediamanager/documents/Publications/Climate/SEI-WP-2014-02-Double-counting-risks-UNFCCC.pdf.

Wikipedia

{{cite report |last1=Schneider |first1=Lambert |last2=Kollmuss |first2=Anja |last3=Lazarus |first3=Michael |title=Addressing the risk of double counting emission reductions under the UNFCCC |publisher=Stockholm Environment Institute |date=April 2014 |url=https://www.sei.org/mediamanager/documents/Publications/Climate/SEI-WP-2014-02-Double-counting-risks-UNFCCC.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{schneider2014addressing, author = {Schneider, Lambert and Kollmuss, Anja and Lazarus, Michael}, title = {{Addressing the risk of double counting emission reductions under the UNFCCC}}, institution = {Stockholm Environment Institute}, year = {2014}, month = apr, url = {https://www.sei.org/mediamanager/documents/Publications/Climate/SEI-WP-2014-02-Double-counting-risks-UNFCCC.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }