AQ Tolerance Proposal Mod 209 – August 2008
Page 2Theme Date Department AQ Tolerances Provide a view of appropriate tolerances for AQ validation Looking only to exclude true outliers to minimise magnitude of failures Data used is from NDM sample information to remove any Shipper impact
Page 3Theme Date Department EUC Band 1 – SSP population Sample of 2310 sites comparing their consumption changes across three years Produces a view of an expected AQ change if the AQ calculation reflected actual consumption
Page 4Theme Date Department EUC Band 1 Variation is consistent year on year Bulk of the population varies between ± 25% +100% to -80% captures 99.2%-99.8% of the changes Suggest these may be appropriate tolerances for EUC band 1
Page 5Theme Date Department LSP EUC Bands Current EUC band break points are, in KWh: EUC band 2 = 73,200 to 293,000 EUC band 3 = 293,001 to 732,000 EUC band 4 = 732,001 to 2,196,000 EUC band 5 = 2,196,001 to 5,860,000 EUC band 6 = 5,860,001 to 14,650,000 EUC band 7 = 14,650,001 to 293,000,000 EUC band 8 = 293,000,001 to 58,600,000 EUC band 9 ignored as these should be DM sites
Page 6Theme Date Department LSP Bands 2-4 Sample of 5,576 sites comparing their consumption changes across three years Produces a view of an expected AQ change if the AQ calculation reflected actual consumption, as for SSP
Page 7Theme Date Department EUC Band 2-4 Variation is consistent year on year Bulk of the population varies between ± 50% +100% to -80% captures 98.8%-98.9% of the changes
Page 8Theme Date Department Outliers for bands 2-4 Number of outliers for bands 2-4 above 100% only varies slightly by band (Shows % of those failing 100% tolerance by EUC band) However the % the outliers vary by is different
Page 9Theme Date Department Tolerances for bands 1-4 Suggested tolerances are: Band 1+100%-80% Band 2+300%-80% Band 3+200%-80% Band 4+200%-80% As these tolerances are similar and a small percentage of the population is outside band 4 suggest extending band 4 to cover all other EUC bands