13.—(1) Where the total obligation for an obligation period is calculation A, in order to discharge its renewables obligation in respect of electricity that it supplies to customers in England and Wales during that period, a designated electricity supplier is required to produce 0.154 UK ROCs for each megawatt hour of electricity so supplied.
(2) Where the total obligation for an obligation period is calculation B, the number of UK ROCs that a designated electricity supplier is required to produce in order to discharge its renewables obligation in respect of electricity that it supplies to customers in England and Wales during that period is, for each megawatt hour so supplied, equal to—
(3) The Secretary of State must publish, by the 1st October preceding an obligation period, the number of UK ROCs that a designated electricity supplier is required to produce in respect of each megawatt hour of electricity that it supplies to customers in England and Wales during that period in order to discharge its renewables obligation for that period.