Carbon Offset Standards, Methodologies and Protocols
The American Carbon Registry (ACR) registers voluntary carbon market projects that meet the ACR Standards, as described below. In addition, ACR has been approved by the California Air Resources Board (ARB) as an Offset Project Registry (OPR) for the California compliance market.
California Compliance Offset Protocols
To be eligible for compliance in the California cap-and-trade system, offset projects will be required to use ARB-approved compliance or early action offset protocols, to be verified by ARB-approved verification bodies, and to register on ARB-approved OPRs. For more information on OPRs, the compliance offset protocols and compliance offset project listing, see our California Compliance Offset Projects page.
American Carbon Registry Standards and Methodologies
The American Carbon Registry (ACR) publishes standards, methodologies, protocols and tools for greenhouse gas (GHG) accounting, which are all based on International Standards Organization (ISO) 14064 and sound scientific practice. ACR only registers project-based carbon offset tons that are real, additional, permanent and independently verified.
ACR process for development and approval of standards and methodologies is led by a qualified technical team. Approval includes a public comment period and a scientific peer review process, a rigorous technical review by experts in the relevant field(s). This combination of approaches ensures that our published standards and methodologies are the highest quality.
The Winrock and ACR team that leads the development of standards and methodologies includes internationally recognized leaders in the forestry, agriculture and clean energy sectors and is widely recognized for its deep expertise in carbon accounting. Team members have co-authored carbon project protocols for the Clean Development Mechanism (CDM), U.S. Environmental Protection Agency (EPA), U.S. Department of Energy (DOE), the U.S. Department of Agriculture (USDA), the USDA Forest Service, the California Energy Commission (CEC), the World Bank, the International Tropical Timber Organization and United Nations organizations.
ACR Standards
| Standard | Version | Status |
|---|---|---|
|
American Carbon Registry Standard |
2.1 2.1 |
Published Published |
ACR Approved Methodologies
New Methodologies
The American Carbon Registry promotes innovation to bring new offsets types to market. Project developers are welcome to submit new methodologies and modified methodologies for evaluation and approval via scientific peer review. Upon public comment and scientific peer review American Carbon Registry may approve and publish the methodology for future use.
Other Accepted Methodologies
American Carbon Registry generally accepts methodologies and tools published by the Clean Development Mechanism (CDM) and ACR-reviewed and approved methodologies from other programs to the extent that they comply with ACR’s Standards. ACR also gives Project Proponents the flexibility to propose modifications to ACR-approved methodologies and tools.
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