The reduction in CO₂ emissions from the use of battery charging photovoltaic roof systems referred to in Article 2(1) shall be determined using the methodology set out in the Annex.

Where a manufacturer applies for the certification of the CO₂ savings from more than one battery charging photovoltaic roof system in relation to one vehicle version, the type approval authority shall determine which of the roofs tested delivers the lowest CO₂ savings, and record the lowest value in the relevant type approval documentation. That value shall be indicated in the certificate of conformity in accordance with Article 11(2) of Implementing Regulation (EU) No 725/2011.