MultiPollutant Emissions Reduction at Xcel Energy Metro Plants

1

• Multi-Pollutant Emissions Reduction at Xcel
  Energy Metro Plants
• Presented at
• EPGA
• Power Generation Committee Conference
• October 28, 2003

2
Introduction

• Background and overview
• Approach
• Alternatives
• Outcome of Xcel Energy Study
• Conclusions

3
Background

• Xcel Energy Response to Minnesota Legislature
  Emissions Reduction Rider
• Voluntary Initiative to Reduce Emissions in the
  Twin Cities Metro Area
• Evaluated Emissions Reduction Scenarios at Four
  Coal-Fired Plants
• Substantial Environmental Benefits to Region

4
General Guidelines

• Focus on Multi-Pollutant Alternatives
• Balance Multiple Stakeholder Interests
• Quantify the Environmental Benefits
• Focus on Commercially Proven Technologies
• BACT and Non-BACT
• Full Life-Cycle Analysis Using Strategist
  Production Cost Model

5
Study Approach

• Evaluate Plant Impacts (Performance, Cost, and
  Emissions)
• Preliminary Capital and Annual Operating Costs
• Selecting Technologies for Further Evaluation
• Develop Base and Composite Alternatives

6
Range of Options

• Upgrades to Existing Plant Equipment
• Additional Emissions Reduction Equipment
• Natural Gas Conversions
• Repowering Alternatives (Coal and Gas)
• Plant Retirement

7
Emissions Reduction Alternatives

• Combustion Controls
• Low NOx Burners
• Over-Fire Air
• Neural Network
• Other

8
Emissions Reduction Alternatives

• Post-Combustion Controls
• SCR Systems
• Particulate Control Systems
• FGD Systems
• Other

9
Gas Conversion and Repowering

• Natural Gas Conversions
• Direct Fuel Switching
• Combustion Turbine Repowering
• Installation of Combined Cycle Facility
• Coal Repowering
• Fluidized Bed Combustion

10
Repowering Approach

• Phase 1 High Level Desktop Study
• Propose Repower Options
• High Level Capital Cost Estimates
• Fuel Availability and Pricing
• Initial Financial Analysis
• Sensitivity Analysis

11
Repowering Approach

• Phase 2 Conceptual Design
• Site and Plant Layout
• Assessment of Existing Facilities
• Environmental Issues
• Performance and Capital Cost Estimates
• Design Basis and Project Schedule
• Fuel and transmissions studies

12
Repowering Approach

• Phase 3 Design Optimization
• Detail emission and permitting issues
• Refine layout configuration
• Refine capital cost including relocation or reuse
• Part-load and off-design performance issues
• Non fuel OM costs
• Phased project schedule

13
Emissions Reduction Approach

• Onsite Visits
• Initial Screening of Technologies
• Establishment of Design Basis
• Evaluation of Screened Technologies
• Development and Evaluation of Compliance
  Scenarios
• Life-Cycle Analysis Using Cost Model

14
Summary of Units
15
Typical Site-Specific Constraints
High Bridge backend photo here?
16
Matrix of Screened Technologies
17
Screening Guidelines

• Commercially Available Technologies
• Mature Technologies W/Guarantees
• Minimum Impact on Balance-of-Plant
• Constructibility and Site-Specific Constraints
• Achievable Emissions Reduction Goals
• Meet Goals of Emissions Reduction Rider

18
Scenarios
19
Scenario Diagram
Insert Highbridge tech selection diagram??
20

Economic Assessment

• Capital Costs
• Operating and Maintenance Costs
• Environmental Externalities
• Capacity Factors, e.g. Unit Dispatch
• Production Cost Model

21

A.S. King Generating Plant
Proposed Layout of Emissions Reduction Equipment
22
A.S. King Generating Plant
23
Composite Solutions
24
Emissions Reduction Results
25
Conclusions

• Maximize Environmental Benefits and Reduce
  Emissions
• Improved Plant Reliability
• Increase System Capacity
• Maintain Diversity of the Fuel Supply
• Utilize Existing Infrastructure
• Significant Benefits for Stakeholders

26
Bottom Line

• A deliberate approach will identify viable
  options to reduce emissions, optimize the value
  of existing assets, maintain system reliability,
  and manage regulatory uncertainty.

27

• Comments/Questions
• Contact information
• Russell C. Girtz, PE
• Black Veatch
• [phone]
• girtzrc_at_bv.com