Enduring Exit Regime & NTS Risk Management Processes
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Transcript of Enduring Exit Regime & NTS Risk Management Processes
Enduring Exit Regime & NTS Risk Management Processes
Offtake Arrangement Workstream – OAD Section I Review Group 316
2
Agenda
Enduring Exit Regime & NTS Risk Management Processes - Overview
Real-time Network Modelling Tools
NTS Risk Management and Constraint Management
Next Steps Discussion
Flow Swapping Process
3
Constraint Forecasting Overview
Telemetry
Physical & Commercial Constraint
Management Tools
DFN Data
OPN Data
On-line Network Modelling & Assessment
Within Day Constraint Management Strategy
Constraint Forecasting & Identification
4
Risk in the Enduring Regime
Potential risk generated due to Interruptible NTS Offtakes becoming Firm NTS Offtakes
More Offtakes & greater Volatility/System Flexibility
Zero Exit buyback target and 100% exposure to NG with no collar on the costs
No Exit equivalent of an Entry “TFA”. Therefore constraint management must be carried out BEFORE the constraint occurs
Many locations complicates risk analysis and constraint management decisions
5
Risk in the Enduring Regime
Broadly, there are two main issues that could give rise to an NTS Exit constraint:
1. The flat supply rate is too low to meet the flat demand rate in an area of the network and pressures become critical.
2. The aggregate within day flow variations remove too much linepack and pressures become critical
Scenario 2 is driven by the offtake flow profiles, therefore in order to forecast and mitigate the risk of this scenario day ahead and within-day, good OPN data is essential
6
Risk Associated with OPN Data
Telemetry
Physical & Commercial Constraint
Management Tools
DFN Data
OPN Data
On-line Network Modelling & Assessment
Within Day Constraint Management Strategy
Constraint Forecasting & Identification
Risk of DELAYED
Constraint ID
Risk of taking inefficient actions
Risk of delays, rendering some tools
useless
Risk of INCORRECT Constraint ID
Delayed or Inaccurate OPN Data
Risk of Increased Constraint
Management Costs
7
Constraint Management (CM) Tools
There are more tools available and no reactive tools (interruption) to deal with Exit constraints in the Enduring Exit regime, therefore more time required to make efficient constraint management decisions
No constraint management tool will have immediate effect, each of the tools have differing lead times
Delayed constraint identification may leave some constraint management options unavailable/ineffective
Delayed constraint identification is likely to drive up constraint management costs
8
Potential CM Tools that rely on OPN Data
Offtake Profile Notice (OPN) Rejection OPN data required to run process
Flow-Swapping OPN data required to run process
Offtake Reduction Invitations OPN data required to run process
Restricting within-day Firm Capacity Release Day ahead OPN analysis to identify potential constraints
Constrained Storage Utilisation OPN analysis to identify constraint
Surrendering Daily NTS Exit (Flat) Capacity OPN analysis to identify constraint
Exit Capacity Constraint Management Agreements OPN analysis to identify constraint
Locational Buy Actions OPN analysis to identify constraint
Operating Margins Utilisation OPN analysis to identify constraint
Off-Peak Capacity Management OPN analysis to identify constraint
9
Benefits of OPN Data Accuracy
Telemetry
Physical & Commercial Constraint
Management Tools
DFN Data
OPN Data
On-line Network Modelling & Assessment
Within Day Constraint Management Strategy
Constraint Forecasting & Identification
Early Constraint ID
Accurate Constraint ID
Accurate & Timely OPN
Data
More certainty of Capacity Availability
Better Gas Quality Forecasting
Increased Efficiency of Compressor Management
Increased Efficiency of OUG & UAG Management
Better FWACV Handling
Flow Forecasting for Maintenance Purposes
Increased Model Accuracy
And more…..
Reduced CM Costs & Risk
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Benefits of OPN Data Accuracy
Good within day forecasting will drive down untimely and exaggerated constraint management instances
Better on-line network modelling will help deliver more optimised NTS operation; ultimately reducing NTS operating costs through efficiency savings (compressor costs, Emissions, UAG etc)
Greater certainty of within day capacity availability means more capacity requests will be fulfilled beyond what is obligated.
Summary
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Summary
The enduring exit regime removes the option of interruption from NTS’s demand management tool kit. As interruption was a close to real time action this both puts more emphasis on;
New exit tools – Of which many use OPN as part of their transaction process. i.e. deviation from prevailing forecast
Forecasting – the use of these tools will need to be assessed at longer lead-times to avoid emergency actions and/or the requirement to curtail exit flows in the first place
More generally optimal NTS operation will ultimately reduce NTS operating costs through efficiency savings (compressor costs, FWACV, UAG etc) through better forward network assessment
Greater certainty of within day capacity availability means we will be able fulfil more capacity requests beyond what is obligated.
13
Position on Development
National Grid NTS continues to believe that receiving information on an offtake by offtake basis on their expected profile is a basic requirement of the system operator in order to meet its safe, efficient, economic and co-ordinated licence obligations.
National Grid NTS would not however be apposed to any changes to either the OPN format, timing and/or associated restrictions in flow profiles (groups and/or single offtakes) if they can be shown to better facilitate these licence conditions between the TSOs.
Overall, National Grid NTS believes the emphasis of ‘section I’ should be on forecast accuracy of the physical profile notification at all lead-times and not simply adherence to prevailing data in order to define allowed ramp rates based on percentage change.
14
Next Steps…?
Flow Swaps – OAD Review
Mike Wassell
16
Background
National Grid NTS and the DNOs may initiate flow swaps to manage their systems economically and efficiently.
OAD section I 2.4 (refer to final slide)
Where National Grid NTS or the DNO User request a flow swap the aggregate of the revised OPN rates for all Offtakes in the same LDZ / NTS Exit Zone are the same as the prevailing OPN aggregate rates
i.e. the mechanism as detailed under OAD Section i is for 1:1 swap of flow from one offtake to one or more alternative offtakes serving the same LDZ.
From the 1st of Oct 2012 DNO User(s) are subject to exit flat overrun charges and any deemed enduring applications that may result from a chargeable exit flat overrun.
17
Example of Flow Swap
Exit Point A Exit Point B
Flow 10 Flow 0
Capacity 10 Capacity 5
National Grid request a Flow Swap from NTS/LDZ offtake A to NTS/ LDZ offtake B of 7
Post Flow Swap
Exit Point A Exit Point B
Flow 3 Flow 7
Capacity 10 Capacity 5
Pre Flow Swap
18
Views sought
Is it felt such a scenario is likely in the enduring regime?
1-in-20 obligation
choice of offtakes to swap flow to on majority of cases
Way forward
is there a case for change to the flow swap rules?
Case for change options ?
19
NTS Initiated Flow Swap OAD Section I
2.4 Revisions requested by National Grid NTS
2.4.1 National Grid NTS may at any time request a DNO to submit revised Offtake Profile Notices for two or more Offtakes for an LDZ, subject to and in accordance with this paragraph 2.4.
2.4.2 National Grid NTS' request shall specify:
(a) the Offtakes in respect of which such revision is requested;
(b) the times with effect from which the DNO is requested to revise the relevant rates of offtake; and
(c) the revised rates of offtake requested.
2.4.3 Any request by National Grid NTS for the revision of any Offtake Profile Notices shall satisfy the requirement that, for all times in the Day, the aggregate, in respect of all Offtakes (serving the same LDZ) for which such request is made, of the revised rates of offtake requested is the same as the aggregate rates of offtake under the prevailing Offtake Profile Notices at the time the request is made.
2.4.4 To the extent to which the revision by the DNO of any Offtake Profile Notice(s) in compliance with National Grid NTS' request would infringe any of the requirements of this paragraph 2 or TPD Section J4.5.2, National Grid NTS shall be deemed to have waived such other requirements (on the assumption that the DNO submits such revised Offtake Profile Notice(s) within 15 minutes after National Grid NTS' request is made).
20
NTS Initiated Flow Swap OAD Section I
2.4.5 The DNO shall comply with National Grid NTS' request unless in the DNO's reasonable opinion the safe and efficient operation of the LDZ (consistent with the DNO's obligations to Users under the Transportation Principal Document) would be materially prejudiced by the flow of gas at the relevant Offtakes on the basis of the requested revisions, in which case the DNO shall:
(a) contact and inform National Grid NTS of the position as soon as possible following receipt of National Grid NTS' request; and
(b) cooperate with National Grid NTS and use all reasonable endeavours to agree upon alternative revisions to
Offtake Profile Notices.