51.—(1) For the purposes of article 50, “post-project SAP band” means the SAP band which is to be determined for the domestic premises by the Administrator—
(a)either—
(i)pursuant to any post-project energy efficiency assessment referred to in article 49(3);
(ii)where the ECO4 project includes the installation of a data light measure or a standard alternative methodology measure to which paragraph (2) applies, by using the energy cost rating equations and the adjusted cost savings for the data light measure or standard alternative methodology measure to calculate the change in the SAP rating of the premises following the installation of the measure; and
(iii)where the ECO4 project includes the installation of a DHC alternative methodology measure, by using the energy cost rating equations and the result of the following formula to calculate the change in the SAP rating of the premises following the installation of the measure—
DHCalt – DHCstandard; or
(b)where the ECO4 project consists solely of data light measures to which paragraph (2) does not apply, by treating the post-project SAP band as being the same SAP band as the pre-project SAP band.
(2) This paragraph applies to a data light measure or a standard alternative methodology measure which—
(a)in the case of a data light measure, is within the participant’s data light measure allowance; and
(b)is not—
(i)the replacement of an efficient boiler with another efficient boiler; or
(ii)the replacement of an efficient heating system with another efficient heating system of the same kind.
(3) For the purpose of paragraph (2)(a), the Administrator is to determine whether a data light measure is within a participant’s data light measure allowance in accordance with article 52.