Evaluating and Improving Carbon Offsetting Programs

The document examines the role of carbon offsets in climate policy, highlighting their ability to reduce mitigation costs and provide sustainability co-benefits. However, it identifies significant risks including additionality, permanence, leakage, and quantification errors. Through a 'road test' of various protocols, the Stockholm Environment Institute (SEI) demonstrates that the amount of offsets credited for the same project can vary by a factor of 2 or more. The brief recommends that offsets be used as transitional tools and that protocols be standardized to ensure consistent calculation of emission reduction credits.

• Carbon offsets can lower the overall cost of meeting emission targets and provide social, environmental, and technology transfer benefits to host regions.
• The Clean Development Mechanism (CDM) was designed to promote sustainable development and technology transfer to developing countries, while other programs often focus on local communities, though success in achieving sustainability benefits has been mixed.
• Offset programs face four primary policy risks: additionality (projects that would have happened anyway), permanence (e.g., forestry projects lost to fire), leakage (increased emissions elsewhere), and quantification and verification errors.
• An analysis of offset standard protocols reveals that the quantity of offsets credited to a single project can vary by a factor of 2 or more depending on the protocol used.
• Aviation offset calculators show significant variance in results based on how non-CO2 climate emissions are treated, a discrepancy driven by policy choices rather than scientific gaps.
• The American Climate and Energy Security Act (ACESA), approved by the US House of Representatives in June 2009, proposed emission targets of 17% below 2005 levels by 2020 and 83% below 2005 levels by 2050, allowing up to 2 billion tons of offsets annually.
• Offset programs should be viewed as transitional instruments to manage near-term costs and encourage low-carbon practices, as some sectors are better served by direct regulation (such as HFC emissions).

APA

Kollmuss, A. (n.d.). Evaluating and Improving Carbon Offsetting Programs. Stockholm Environment Institute. https://www.sei.org/mediamanager/documents/Publications/Climate-mitigation-adaptation/Economics_of_climate_policy/Evaluating-Improving-Carbon-Offsetting-Programs.pdf

Chicago

Kollmuss, Anja. Evaluating and Improving Carbon Offsetting Programs. Stockholm Environment Institute, n.d. https://www.sei.org/mediamanager/documents/Publications/Climate-mitigation-adaptation/Economics_of_climate_policy/Evaluating-Improving-Carbon-Offsetting-Programs.pdf.

Wikipedia

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BibTeX

@techreport{kollmussndevaluating, author = {Kollmuss, Anja}, title = {{Evaluating and Improving Carbon Offsetting Programs}}, institution = {Stockholm Environment Institute}, url = {https://www.sei.org/mediamanager/documents/Publications/Climate-mitigation-adaptation/Economics_of_climate_policy/Evaluating-Improving-Carbon-Offsetting-Programs.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }