1. Review of System Alerts
Transmission Workgroup 7th July 2011

2. Background GBA has been in place for 5 years
Time to review current arrangements
Builds on discussions had in the SCR workgroups, focused on Gas Deficit Emergency arrangements.
Focus is on providing information to the market

3. What Is a Gas Balancing Alert (GBA)?
National Grid have a UNC obligation to notify system users of a potential ‘significant’ end of day (EOD) supply / demand imbalance
A GBA may be issued either day ahead or within day Or
Aimed at prompting a market response to supply or demand

4. Day ahead GBA
UNC describes the day ahead process as D-1 forecast demand being >= forecast total system supply.
The D-1 GBA Trigger Level is based on typical supply levels and forecast demand.
Consider:
Reviewing name (change from a GBA)
Clarifying assessment methodology
Introducing the ability for NGG to recall
What market response is expected?

5. Within Day GBA Consider: Market response versus SO action
Introducing the ability to for NGG to recall
Developing ability to signal a within day issue as well as EOD issue
Information requirements
From SO
From industry
Market response versus SO action

6. Next Steps…
Work with the industry to develop proposals
July Panel – request a review of the GBA process through the Request procedures
National Grid to submit proposal/s in line with the review group conclusions.