Gas Quality Stakeholders

1
Gas Quality Stakeholders Technical Committee
Meeting

• September 20, 2005
• Natural Gas QualityPower Turbine
  PerformanceDuring Heat Content Surge
• Updated Information and Schedule
• William Walters
• Aspen Environmental Group
• Sponsored by the California Energy Commission

2
Update and Schedule

• Sutter Natural Gas Fuel Wobbe was determined.
  Los Medanos, Delta, and Redding as used fuel
  Wobbe cannot be determined with available data.
• Western Midway Sunset had events of reduced fuel
  heat content which caused significant increases
  in CO emissions, but did not significantly impact
  NOx emissions.
• Study will go out for CEC management and data
  provider review later this week, and the Draft
  Study with excel raw data tables should be made
  public as early as late next week.
• Additional work will be funded by the CEC to
  determine potential natural gas quality
  emissions/operations impacts to large power
  boilers. Scope of work should be completed by
  the end of this week and work should begin in
  approximately two weeks.

3
Sutter Natural Gas Fuel Heat Content and Wobbe
4
Sutter CT2 Uncontrolled NOx vs Wobbe
5
Sutter CT2 Ammonia Use vs Wobbe
6
Sutter CT2 Controlled NOx vs. Wobbe

• Summary
• Uncontrolled NOx 15 increase for 3.5 increase
  in Wobbe
• Ammonia use 10 increase for 3.5 increase in
  Wobbe
• Controlled NOx no increase

7
Western Midway Sunset CO Emissionsvs Fuel Heat
Content
8
Western Midway Sunset Description

• Cogeneration 7E turbines with SCR and no CO
  catalyst 25 ppm CO permit limit.
• No significant controlled NOx impacts (i.e.
  reduction) during heat content drop.
• Expensive (250,000) burner modification fixed
  problem.
• Subsequent burner modifications to second turbine
  affected earlier CO emissions fix.