Mandatory Compliance Reduction Standards
Clean Development Mechanism (CDM)
The Clean Development Mechanism is the standard defined by the United Nations Kyoto Protocol in 2006. It has been operational ever since. The CDM is the international standard designed to produce emissions reduction projects in developing countries. Offset projects that are certified under the CDM generate Certified Emission Reduction (CER) credits that they can sell to offset one tonne of CO2. Considering Article 12 of the Kyoto Protocol defined the CDM, these CERs can be used to meet countries' reduction targets defined in the treaty. CDM uses third-party auditing and verification of projects. Ultimately, the CDM Executive Board reviews all projects.
Voluntary Emission Reductions Standards
Verified Carbon Standard
The Verified Carbon Standard (VCS) is a voluntary verification standard operated by Verra, a non-profit organisation. Verra states that there are over 1,700 projects verified under VCS. These projects are responsible for offsetting over 630 million tonnes of GHG emissions. The VCS was first defined by the Climate Group and International Emissions Trading Association (IETA). Once a carbon offset project is verified under the VCS, project developers can be issued Verified Carbon Units (VCUs).
The Gold Standard is one of the voluntary emission standards featured in the Consequence portfolio. There is a Gold Standard for the CDM and the voluntary market, referred to as the Gold Standard Verified Emissions Reduction (GS VER). The GS VER was first released in 2006 by the non-profit foundation WWF-UK. It is a simpler standard than the CDM version, but the verification methodology is the same. The Gold Standard only verifies carbon offset projects in developing countries, specifically those projects involved with renewable energy and energy efficiency.
Voluntary Offset Standard (VOS)
The Voluntary Offset Standard (VOS) is one of the more recent voluntary standards. It was first launched in 2007. Like other standards, it is largely based upon the existing UNFCCC standards. The idea behind the Voluntary Offset Standard is to provide an offsetting standard similar to that of the Kyoto Protocol compliance market.
Climate, Community and Biodiversity Standards (CCB)
The Climate, Community, and Biodiversity Standard (CCB) was developed by the similarly named Climate Community and Biodiversity Alliance. This standard is specifically designed for land-based carbon offsetting projects. Projects under the CCB seek to achieve climate biodiversity and benefits for the local communities. The CCB standard follows the Good Practice Guidance methodologies outlined by the Intergovernmental Panel on Climate Change (IPCC CPG).
Keep in mind that this list is not exhaustive. There are other voluntary reduction standards that verify carbon offset projects beyond these. Nevertheless, these are some of the biggest standards in the voluntary market today.