There can be a time lag between the compensating for a quantity of GHG and the corresponding reduction in emissions. The period of accreditation, i.e. the period when the GHG savings happen, can be :
- Either the duration of the project,
- or the accreditation period defined under Kyoto.
It can be that the accreditation period for the carbon credits is different from the duration of the project. Under CDM, the project holder can chose between two alternatives:
- A fixed non renewable period of a maximum of 10 years,
- A period of 7 years, renewable twice, that is a maximum period of 21 years.
This decision is taken case by case. It depends mostly on the expected performance of the project, its lifespan, the financial package that supports it and the changes in the reference scenario. For each accountability period, the starting date and the duration of the accountability period must be given. This information is made clear in the PDD.
When it is time to renew the accreditation period, the PDD is fully revised and adjusted in order to take into account the changes in the field brought about by the project since its implementation.
Finally, the accreditation period of the VCS methodology differs from the CDM's in that the 10 years period is renewable once.
Carbon Credits ex post and ex ante
We distinguish 2 types of credits:
- The credits ex post : these credits are said to be "acquired". The GHG emissions' savings have already happened on the project.
- The credits ex ante : these credits are said to be "future". They anticipate the future generation of carbon credits.
The GERES's view, as an operator in the field, is to consider this last credit category as a source of prefinancing.
The anticipated sale of credits is particularly well adapted to development projects, especially when they need more or less long phases of assessment and R&D, which are indispensable for the project. But these phases don't produce carbon credits.
Exemples Concrete examples from CO2Solidaire projects:
> Cambodia : the emissions saved are verified every year by an DOE accredited by the UN. So they are "acquired" credits. For example, in 2009, the verifivation by Bureau Veritas determinde the value of GHG savings in 2008. However, it is possible for any project having acquired credits to reserve future credits.
> Afghanistan : the building construction program started in January 2003 and the accredition period is for 10 years from the year of the construction of the buildings. We have then as much period of accreditation as completed constructions every year. The first is from 2004 to 2013, the last one from 2012 (last year of the project) to 2021.
> Indian Himalaya : the construction program of 1000 passive solar buildings started in 2008, the accreditation ^period is for 10 years starting from the year of the construction of the buildins. The PDD validation and the project verification took place in 2010.
> Marocco : the program started in 2008, its accreditation period is for 10 years. PDD validation is planned for 2012.