1. SLIDE 1 MANAGING THREATS TO SYSTEM SECURITY IN THE DECLARED TRANSMISSION SYSTEM September 2015 PRESENTED BY TIM ABERNETHY “What we do behind the scenes to ensure Victorians stay warm”

2. SLIDE 2 AGENDA 1.What does my team do at AEMO? 2.What is a Threat to System Security? 3.What are AEMO’s obligations? 4.How do we do it? 1.Prevent 2.Respond 3.Recover

3. SLIDE 3 WHAT DOES GAS REAL TIME OPERATIONS DO AT AEMO? Short Term Trading Market (STTM) Gas Supply Hub Declared Wholesale Gas Market (DWGM) Declared Transmission System (DTS) Sydney STTM Hub Brisbane STTM Hub Adelaide STTM Hub Victoria DWGM and DTS Wallumbilla Gas Supply Hub

4. SLIDE 4 WHAT IS A THREAT TO SYSTEM SECURITY? Gas Quality not in limits; or Threat to public safety; or Threat to the supply of gas to customers; or System pressures and flows.

5. SLIDE 5 WHAT CAN CAUSE A THREAT TO SYSTEM SECURITY? Injection Source Failure Asset Failure Unexpected Demand

6. SLIDE 6 WHAT CAN CAUSE A THREAT TO SYSTEM SECURITY Methane Hydrate Source: Centre for Gas Hydrate Research Gas Quality

7. SLIDE 7 WHAT ARE AEMO’S OBLIGATIONS? AEMO must operate the DTS in a way that minimises or averts a threat to system security AEMO must give notice of a threat to system security AEMO must intervene if it believes the intervention is required to resolve the threat to system security AEMO must give the market the opportunity to resolve the threat.

8. SLIDE 8 HOW DO WE DO IT? Identify and Prevent Respond Recover Threat to System Security? Yes No

9. SLIDE 9 PREVENTION AND THREAT IDENTIFICATION

10. SLIDE 10 PREVENTION AND THREAT IDENTIFICATION Declared Transmission System Winter Operations – Trent Shinners Monitoring o Linepack o Demand o Supply o Weather Forecast o GPG Prevention o Compressors o Pressure Regulating Stations

11. SLIDE 11 RESPOND

12. SLIDE 12 RESPONSE 1.Market Response 2.Peak Shaving gas 3.Ad Hoc Schedules 4.Directing participants to inject or withdraw gas 5.Curtailment Dandenong LNG Tank Source: The Australian Pipeliner

13. SLIDE 13 RESPONSE PEAK SHAVING GAS Dandenong LNG Tank Approx 70% of winter system demand

14. SLIDE 14 RESPONSE PEAK SHAVING GAS – 21 ST JUNE 2013

15. SLIDE 15 RESPONSE CURTAILMENT Source: Snowy Hydro Source: Qenos 1. Gas Powered Generators and Interconnected Pipelines 2. Industrial Customers 3. General Public (Tariff V) Source: GasWorks 4. Essential Services Source: Panskomd

16. SLIDE 16 RECOVER

17. SLIDE 17 RECOVERY(FROM CURTAILMENT) Rationing and Recovery Principles: o Priority given to gas system pressures o Minimise economic impact, health issues o “Jobs before heating” The Age

18. SLIDE 18 SUMMARY Identify and Prevent DTS Winter Operations – Trent Shinners Respond e.g. Peak Shaving Gas or Curtailment Recover “Jobs Before Heating” Threat to System Security? Yes No

19. SLIDE 19 THANK YOU!