1. Start date How old can a PV Climate project be? Expand Typically, a prospective project will not yet be operational and will use the PV Climate from the outset. However, it is possible for a project that is already operational to become an approved PV Climate project, provided it can meet the requirements of PV Climate v5.0. In such instances, retroactive crediting is possible for up to three years prior to beginning the registration process with Plan Vivo, provided that there is a strong argument for additionality and it can be evidenced that the project always intended to become carbon certified and generate carbon credits.