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OPNs & LDZ Demand Forecasts

Understand the challenges in OPNs and LDZ demand forecasting, propose solutions for accuracy and timing issues, and address discrepancies affecting the NTS system. Ensure better information exchange among stakeholders for enhanced performance.

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OPNs & LDZ Demand Forecasts

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  1. OPNs & LDZ Demand Forecasts Chris Shanley & Nick Reeves

  2. OPNs/LDZ Demand Forecasts from DNs to NTS • Issue originally raised through SOMSA SC2004 work • Proposed that NG NTS pursue any identified issues with the DN demand forecasting processes via the Offtake Committee • OPN Accuracy and Timing – means data is not currently utilised in the NTS Demand Forecasting process • Removal of SC2004 will mean NG NTS will no longer have access to certain information • To assist in development of each DNs new systems, clarity is required on how best information can be provided at the right time • DNs are wary about redesigning systems/processes to meet any current SO incentives that may disappear in a couple of years • What are the problems impacting the OPN process and is this the best way forward to correct these inconsistencies • NTS to liaise internally to gain a greater understanding of the issues and potential options and report back to the Offtake Committee

  3. NTS / LDZ Demand Forecasting* D: 12:00, 15:00, 18:00, 21:30, 02:00 D-1: 14:00, 18:00, 00:00 Demand Forecasting Process - High Level Overview NTS Related Activities DN Inputs D-1 D SC2004 GTMS/iGMS (METGAS) NDM Nominations / Demand Attribution D-1: 14:00 System Balancing OPF * UNC publishing times are shown – for example the D-1 13:00 demand forecast must be published by 14:00

  4. DN Inputs SC2004 METGAS OPF DN Inputs • Currently DNs submit information to National Grid NTS via 3 main routes • Forecast LDZ demand via SC2004 • Forecast NTS take via METGAS screens within GTMS • METGAS inputs provide NTS ‘take’ information from DNs • NTS ‘take’ = Demand Forecast + VLDMCs - (Interruption, LNG Boil Off, On Shore Fields) +/- Stock Change & Inter LDZ transfers • Offtake Profile Notifications (also provides forecast NTS take) • UNC Obligations on DNs to provide D-1 forecast info is stated as follows: • An “End of Day Demand Forecast Notice” for; • Any relevant DN System Exit Point by 12:00 • All LDZ/NTS offtakes by 13:00 • An OPN setting out rates of offtake throughout the Gas Flow Day by 18:00 • UNC Obligations on DNs to provide revised OPNs if there is an increase or decrease in rate of offtake

  5. NTS / LDZ Demand Forecasting D: 12:00, 15:00, 18:00, 21:30, 02:00 D-1: 14:00, 18:00, 00:00 NTS / LDZ Demand Forecasting • As per UNC H 5.2; Transporters must notify demand forecasts (both LDZ and NTS) to Users at staggered times during D-1 and D • This is achieved by publishing data via National Grid Website • For LDZ info, LDZ forecasts within SC2004 flow through to NTS iGMS system and are published as is (SIS03 Report) • For NTS Demand Forecast, National Grid NTS use: • An NTS Total system demand forecast comprises of data from all offtakes, i.e. direct connects, interconnector, LDZs, etc • LDZ NTS take • OPF process will substitute (last approved from previous day) OPN data that is not provided • METGAS screens in iGMS are used to correct any substitute

  6. SO Incentive Scheme • The D-1 14:00 total system forecast has an SO incentive for accuracy within 3% of actual demand (D+5) • Annual scheme • SO Incentives from April 2010 • National Grid leading on development of Initial Proposals • Initial views received are that current information/incentive is valuable to industry parties • Discussions being held on whether incentive should be extended to cover other times, for example D-1 16.00 • Some respondents highlighted that more accurate NDM forecasts would be useful

  7. NDM Nominations / Demand Attribution D-1: 14:00 NDM Nominations & Demand Attribution • D-1 NDM Noms are based on LDZ demand forecasts • SC2004 forecasts flow through to Gemini • NDM Noms calculated based on demand modelling • NDM Noms provided to Users via Gemini by 14:00 D-1 • Obligations are within UNC Section C 1.2 & 1.5 • Forecasts will need to be sent via new systems (SC2004 replacements)

  8. System Balancing System Balancing • National Grid NTS calculate Predicted Closing Line Pack (PCLP) and undertake balancing actions based on input and output information • Input Notifications from Delivery Facility Operators • Output Notifications provided to NTS by both Users (Direct Connects) & DNs respectively • For LDZ NTS take, NTS use the following (depending on timing of PCLP calculation) • METGAS information • Offtake Profile Notifications

  9. OPN Timing and Accuracy (1) • OPN timing and accuracy – D-1 Forecast? • DN OPN processes run later than NTS demand forecast round up times • No consistency between SC2004, METGAS & OPN info • Differences between LDZ demand & NTS Take • METGAS currently most timely source • The first OPN for Day Ahead usually arrives around 16.00 and is not used for the SO Incentive D-1 13.00 NTS Demand Forecast

  10. OPN Timing and Accuracy (2) – Mod history • Mod 0100 (Aug 2006) • Proposal sought to amend UNC section J and OAD to move initial submission time (14.00) for DN OPN to 12.30 and any other exit point to 12.00. • Mod 0123 (Urgent - Dec 2006) • Mod 0100 would require significant investment in systems, contractual arrangements and working practices • Proposed alternative route to allow UNC parties to meet NTS forecasting requirement • Amend current obligation on DNOs to submit day ahead forecast demand in time for 14.00 Total system Demand Forecast • Shippers provide exit point level offtake data to relevant transporter by 12.00 – predicted end of Day Offtake Quantity (LDZ Summary OPN (SOPN)) • DNOs would provide NTS SOPN by 13.00 (same as before Mod 0100) • We are led to believe that this requirement is met through the METGAS report

  11. Current Requirements • To allow NG NTS to conduct their Demand Forecasting related activities ASIS: • NTS / LDZ Demand Forecasting • LDZ demand forecasts within SC2004* need to flow through to NTS iGMS system • DNs need to populate data that feeds into METGAS screens in iGMS to enable NTS to create their demand forecast • NDM Nominations & Demand Attribution • SC2004* LDZ Demand forecasts need to flow through to Gemini • System Balancing • LDZ NTS take - METGAS or OPN (depending on timing of PCLP calculation) • Offtake Profile Notifications • OPNs would be used more/exclusively if timing issues were overcome – METGAS preferred • Do we need to introduce governance arrangements (processes, audit, etc.) for METGAS? * SC2004 or replacement system

  12. Future Considerations • Are we going to need more accurate and timely [within day] OPN (nodal offtake and flow information) in the future? • Flow Flex – not included in scope of Mod 0195AV • Flow Flex was to be driven off OPN data • NG System Flex initiative underway • Driven by concerns over the ability to manage a more volatile system due to wind, etc. • Exploring what indicators might quantify the need for change? • line pack utilisation and OPN accuracy • Ofgem Consultation to be undertaken in near future • National Grid NTS are also looking at how they will manage the system/constraints in the future • OPN data will be utilised in any associated tools

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