Following consultation, Ofgem announced on Monday 16 November its final position on ECO3
methodologies for calculating electricity and gas supply volumes. In reflection of the five responses, the
regulator confirmed it will amend its methodologies for ECO3 phase three and four to include half-hourly
settlement data and to calculate the number of customers who have half-hourly settlement data using the
D0030 Aggregated Distribution Use of System report, as this is already utilised by suppliers. Ofgem also
included a methodology for suppliers to calculate electricity supply. Obligated suppliers are now requested
to notify the regulator on the number of domestic customers on 31 December and the amount of gas or
electricity supplied during the relevant year by 1 February 2020. The final ECO3 Guidance on Supplier
Administration is anticipated to be published in January 2020.