Project: May 05-10

1
Project May 05-10
Economic Dispatch of Combined Cycle Generators
Abstract
Combined-cycle generating units are being added
to current power systems in order to meet
increasing load requirements as efficiently as
possible. They consist of two simple-cycle
combustion turbines with a heat recovery steam
generator. Combined-cycle units exhibit
non-monotonically increasing cost curves which
cannot be handled by classical methods of
economic dispatch optimization such as
Newton-Raphson, binary-search, and other
lambda-iteration techniques. The project team
will develop an algorithm to calculate optimal
economic dispatch including both monotonically
and non-monotonically increasing generators.
Major milestones include development of the
optimization algorithm, implementation of the
algorithm in Microsoft Excel using Visual Basic
macro programming, and delivery of the software
and documentation to the client. Optimal results
will allow for power to be produced at the lowest
possible cost to the client while prolonging the
life of each generating unit.
Project Requirements cont.
Introduction

• Problem statement
• Develop an algorithm for the optimal economic
  dispatch of monotonically and non-monotonically
  increasing generators
• Create a program to implement the algorithm
• Operating environment
• Use Visual Basic for macro creation in Microsoft
  Excel
• Real-time economic dispatch at control center
• Intended User
• MidAmerican employees
• Generation dispatchers
• Intended Uses
• Optimize the economic dispatch of monotonically
  increasing and non-monotonically increasing
  generators
• Benchmark cost curves for future algorithm
  designs
• Assumptions
• Enumeration / iteration will be used as the
  optimization method for the algorithm
• 12 monotonically increasing units and 2 sets of
  non-monotonically increasing units will be
  modeled

• Measurable Milestones
• End-product Design Dec. 13,
  2004
• Product prototype Feb. 21,
  2005
• Product testing Apr. 04,
  2005
• Product documentation Apr.
  11, 2005
• Product demonstration Apr.
  18, 2005

Technical Approach and Considerations

• Proposed Approach
• Technologies Considered
• Visual Basic (required)
• Microsoft Excel (required)
• Testing Considerations
• Test the algorithm using C
• Client testing

Solve for Monotonically Increasing Units
Load User Defined Inputs
Combine Solution Sets
Run Algorithm
Output Optimal Dispatch
Solve for Non-Monotonically Increasing Units
Resources
Financial Requirements
Project Requirements
Item W/O Labor With Labor
Bound Project Plan 20.00 20.00
Poster 62.00 62.00
Labor at 10 per hour
McDowell, Edward 1,550.00
Mott, Richard 1,540.00
Peterson, Adam 1,510.00
Thorp, Seth 1,560.00

Total 82.00 6,242.00

• Design Objectives
• Flexible program design
• Well-commented program code
• Comprehensive iteration scheme
• Functional Requirements
• Provide best generator dispatch
• Output iteration calculations
• Design Constraints
• Five minute limit on iteration run time
• Expandable for future non-monotonically
  increasing units
• Clear box design enabling modifications of
  program
• Ability to include unit commitment

Personal Effort
  Total Hours
Edward McDowell 155
Richard Mott 154
Adam Peterson 151
Seth Thorp 156
Total 616
Summary
The project will create a software application
that will seek to produce the most economic power
distribution between monotonically and
non-monotonically increasing generators. An
algorithm will be created to incorporate the two
types of generators and will be combined with a
user interface to produce a usable program. This
program will be written in Microsoft Excel using
Visual Basic macros and will meet the outlined
requirements. MidAmerican Energy can expect to
benefit from this project through a reduction in
fuel costs due to improved generator dispatch and
prolonged generator life.
Greater Des Moines Energy Center Combined Cycle
Plant
Diagram of a Combined Cycle Generator
Contact Information
Project Team Members Edward McDowell,
EE emcdowel_at_iastate.edu Richard Mott, EE /
Econ pkrmott_at_iastate.edu
Faculty Advisors Dr. John Lamont jwlamont_at_iastat
e.edu Dr. James McCalley jdm_at_iastate.edu
Client Contacts Alan Oneal aroneal_at_midamerican.c
om Matt Mitchell mmitchell_at_midamerican.com
Adam Peterson, EE ampete_at_iastate.edu Seth
Thorp, EE sthorp_at_iastate.edu