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Overview of Supplier Volume Allocation. David Osborne. Introduction. Supplier Volume Allocation (SVA) Purpose History Supplier Hub and other participants Interface with Central Services. Generation, Transmission, Distribution and Supply. Generation. Generation.
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Overview of Supplier Volume Allocation David Osborne
Introduction • Supplier Volume Allocation (SVA) • Purpose • History • Supplier Hub and other participants • Interface with Central Services
Generation, Transmission, Distribution and Supply Generation Generation Transmission Network(the ‘Grid’) Grid Supply Points 400/275 kV Distribution Network 132 kV Supplier’s customer factory >100 kW Supply Supplier’s customer - domestic GSP Group
SVA History • 14 Regional Electricity Boards • 1990 – competition in Supply > 1MW • 1994 – extended to > 100 kW • 1998 – full competition • 2000+ – competition in agency services • 2001 – NETA Arrangements • 2005 – BETTA Arrangements
314,000,000 MWhdemand per year (45% Half Hourly Metered) Metering Systems 29 million Metering Systems
Profiling • Over 29 million NHH meters • Settlement operates on HH basis • Consumption is profiled to allocate annualised consumption to Half Hours
Roles and Responsibilities – Suppliers and SMRAs • Supplier Meter Registration Agent (SMRA) • 1 per GSP Group • SMRA service - LDSO licence requirement • Provides a registration service • LDSO Party to the BSC • Supplier • Discharges many obligations through Supplier Agents (MO, DC and DA) • Registers “Supplier Hubs” in each GSP Group • Supplier Hub = combination of Supplier, Meter Operator, Data Collector and Data Aggregator in each GSP Group • Multiple combinations of “Supplier Hubs” operate within each GSP Group • Supplier is a Party to the BSC
Roles and Responsibilities – Supplier Agents • Supplier Agents (NHH and HH) • Meter Operator - asset provider and maintainer • Data Collector - data retrieval and processing • For NHH - determines EAC/AA data based on Daily Profile Coefficients received from the SVAA • Data Aggregator - provides aggregated meter data by Supplier, GSP Group, Profile Class to the Supplier Volume Allocation Agent • Supplier Agents are not BSC Parties
Roles and Responsibilities – BSC Agents • Appointed by ELEXON to perform certain activities • ELEXON cannot be a BSC Agent • Supplier Volume Allocation Agent (SVAA) • Calculate Supplier volumes • Produces Daily Profiles for use by NHH Data Collectors • Manages market data • Contracts for Sunset Data and Temperature Data • Applies GSP Group Correction
Roles and Responsibilities - BSC Agents • Profile Administrator • Programme of load research in order to collect demand data from customers • Derives Regression Coefficients • Teleswitch Agent • Provides switching times for certain groups of customers
BSC Systems and Processes • Processes undertaken by Suppliers/Supplier Agents are highly prescribed in the BSC and procedures • Some systems provided centrally and operated under licence • EAC/AA software • NHHDA software
SVA Process Overview Industry Processes Central Systems Processes Central Data Collection Agent Profile Administrator DC/DA appointments Supplier SMRS Regression Data GSP Group Take Aggregated consumption Data Appointment and Settlement Data SVAA Data Collector Teleswitch, sunset and temp data Meter Operator Data Aggregator Allocated Supplier Volumes Other Data Providers NHH Daily Profile Coefficients Settlement Administration Agent
Timing of Settlement Runs Final Reconciliation Final Settlement Run 2nd Reconciliation Settlement Day +39WD +30Months +154WD Time +5WD +16WD +84WD +292WD 1st Reconciliation Post-Final Settlement Run 3rd Reconciliation Interim Information Settlement Run 30% 60% 80% 97% n/a Reading Targets Supplier Charges
Costs Year to March 2008 £m • Supplier Volume Allocation • SVA Operations • Data Transfer Service (DTS) • Profiling • Software Support • Entry Process/Qualification • Other • SVA Total Cost 1.59 0.58 0.74 0.87 0.41 0.14 4.33
Electricity Metering & Settlement Jon Spence, ELEXON 8 November 2008
The Ice Cream Test • If 50% of annual ice cream sales occur in August • And 50,000 ice creams are sold in August • What are the annual sales? ______ • If 5% of annual ice-cream sales occur on 5th August • How many are sold on 5th August? ______
That’s how electricity settlement works! • What do profiles look like? • How are they used to annualise customer demand? • How are they used to estimate Suppliers’ demand in a given half hour?
Yearly Profile – domestic unrestricted April to March
Profiling Cycle Year one – data logged at sample 2,500 customers (split 50-50 between domestic & non-domestic) – confidentialprocess Year two – data analysed Year three – profiles used in Settlement process
Profiling process Temperatures and sunset times switching times Sample data Data Collector SVAA Annualise Meter Advances Daily Profile Production Load Research Regression Analysis Profile Administrator SVAA Deemed Take calculation Yearly Supplier Reports Daily
Data Collector An estimate of annual consumption is extrapolated from meter advance using profile 1,150 kWh in 90 days 4,250 kWh per year (AA)
EACs/AAs • Annualised Advance • the rate of consumption for a Settlement Register over the period between two meter readings. • Estimated Annual Consumption • an estimated rate of consumption used in Settlement until an AA is calculated • similar to an Annual Quantity (AQ) in Gas?
AA 1 EAC 1 AA 1 AA 2 EAC 2 AA 1 AA 2 AA 3 EAC 3 EAC / AA cycle timeline INITIAL EAC “carried forward” EAC is calculated using latest AAand “brought forward” EAC (weighted using theprofile over the meter advance period)
1/1/07 31/3/07 MR1 7,000 MR2 9,000 MA = 2,000 MAP∑DPCs = 0.4 Previous EAC = 3000 AA Example AA = Meter Advance / MAP∑DPCs = 2,000 / 0.4 =5,000
1/1/04 31/3/04 MR1 7,000 MR2 9,000 MA = 2,000 MAP∑DPCs = 0.4 Previous EAC = 3000 EAC Example EACnew AA = 5,000 EACnew = AA * (MAP∑DPCs * SP) + EACold * (1-MAP∑DPCs * SP) EACnew = 5,000 * (0.4 * 2) + 3,000 * (1 – (0.4 * 2)) = 4,600 EACnew = 4,000 + 600
Data Aggregation Estimated yearly demand values are added up for customerswith same Supplier, Profile Class, meter configuration by a Data Aggregator to give theestimated yearly demand for Settlement Class ora “super customer”
NHH Data Aggregation • NHH Data Aggregator aggregates annualised consumption for each distribution area, Settlement Date and Run Type • an AA is used in preference to an EAC • a default value is used where there is no AA or EAC
AA / EAC (Meter) Meter Advance Daily Profiles Aggregated AA / EAC (Supplier/Profile Class) HH profiled demand (Supplier) Half Hourly Profiles The NHH Settlement Cycle
Supplier Volume Allocation Agent • applies half hourly profile to aggregated AA/EACs to calculate profiled HH demand per Supplier • estimates line losses based on factors from Distribution businesses • applies ‘GSP Group Correction’
HH GSP Group Correction Electricity is metered twice – at customer’s meter and at Grid Supply Point (i.e. entry/exit points to distribution networks) NHH GSP GROUP TAKE NHH HH
GSP Group Correction • NHH demand (import less export plus estimated line losses) are “corrected” so that total NHH and HH volumes for the Settlement Period equal the GSP Group Take • volumes attributable to each Supplier are scaled up or down in each HH/GSP Group via CF • since GSP Group correction is effectively distributing “settlement error” amongst Suppliers, it makes sense to correct those categories of consumption that are more prone to error than others • NHH is obvious candidate as Settlement Period values are estimated (using profiles) rather than metered.
The Ice Cream Test • If 50% of annual ice cream sales occur in August • And 50,000 ice creams are sold in August • What are the annual sales? ______ • If 5% of annual ice-cream sales occur on 5th August • How many are sold on 5th August? ______ PrA NHH Data Collector PrA SVAA