Greater Des Moines Energy Center
Combined Cycle Plant
Diagram of a Combined Cycle Generator
AbstractAbstract
Combined-cycle generating units are being incorporated into the current power systems in order to meet peak loading contingencies as efficiently as possible. Combined-cycle generating units consist of two simple-cycle combustion turbines and one heat-recovery steam generator. Combined-cycle generating units exhibit non-monotonically increasing cost curves which cannot be solved by classical economic dispatch optimization methods. The project team is modifying and redesigning a pre-existing algorithm to calculate optimal economic dispatch, including both monotonically and non-monotonically increasing generators, with a shorter solution time. Major milestones include comprehension of the pre-existing optimization algorithms, implementation of the algorithms in Microsoft Excel using Visual Basic macro programming, redesign of the optimization algorithm for faster solution speed, 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.
Matthew Ellis [email protected]
Noraima Fernandez [email protected]
Jeremy Hamilton [email protected]
Robert Walter [email protected]
Alan [email protected]
Project Schedule Gantt ChartProject Schedule Gantt Chart
Financial Requirements/Personnel EffortFinancial Requirements/Personnel Effort
http://seniord.ee.iastate.edu/may0607/
IntroductionIntroduction
Resources and ScheduleResources and Schedule
The project will build upon a software application that will seek to produce the most economical power generation, with as quick of solution times as possible, between monotonically and non-monotonically increasing generators. The algorithm will be able to handle more generator combinations and will be combined with a more aesthetically pleasing user interface to produce a more usable application. This program will be written in Microsoft Excel using Visual Basic macros and will meet the many outlined requirements. MidAmerican Energy can expect to benefit from this project through a reduction in fuel costs due to improved generator operation.
Closing SummaryClosing Summary
Team MembersTeam Members ClientClient
Dr. John [email protected]
Faculty AdvisorFaculty AdvisorWebpage
Project RequirementsProject Requirements
May 06-07May 06-07
Problem StatementProblem Statement General Problem Statement
Conventional monotonically increasing algorithms will not dispatch non-monotonically increasing units without altering the data, thus currently an optimal solution can not be found. General Problem Solution• Modification of a pre-existing algorithm incorporated into Microsoft Excel macros in order
to give MidAmerican Energy the lowest cost solution to meet their power demand with the shortest solution time possible.
• The project team will focus their concentration on improving the structure of the unit commitment page, reorganizing the way output is displayed, implementing a main menu, and finally restructuring the code to allow the user to dispatch only a range of hours.
Operating EnvironmentOperating Environment• Use Visual Basic macro programming embedded in the form of a Microsoft Excel
workbook• The software will run on a windows-based system with adequate processing capabilities
User User • MidAmerican generation dispatchers• MidAmerican short-term energy traders
UsesUses• Optimize the economic dispatch of monotonically increasing and non-monotonically
increasing generators• Benchmark cost curves for future algorithm designs
AssumptionsAssumptions• Enumeration / iteration will be used as the optimization method for the algorithm• 12 monotonically increasing units and 2 sets of non-monotonically increasing units are
being modeled
LimitationsLimitations• Software shall use Microsoft Excel as the interface• Input data for generating units shall use piece-wise linear incremental cost curves• Results must be written into a single Excel workbook
Expected End-ProductExpected End-Product• Excel workbook file with Visual Basic macros • User instructions documentation• Easy to use interface
Item W/O Labor With Labor
Bound project plan (2) $8.88 $8.88
Bound design report (2) $8.88 $8.88
Bound final report (2) $8.88 $8.88
Poster $20.00 $140.00
Subtotal $46.64 $166.64
Labor at $10 per hour: Total hour:
Ellis, Matthew 204 $2,040.00
Fernandez, Noraima 201 $2,010.00
Hamilton, Jeremy 202 $2,020.00
Walter, Robert 203 $2,030.00
Total 810 $8,266.64
Proposed ApproachProposed Approach
Proposed ApproachProposed Approach
Technologies Considered: • Visual Basic (required by client) • Microsoft Excel (required by client)
Testing Considerations:• Test the algorithm using Matlab Linear Programming• Client testing in client’s environment
Economic Dispatch of Non-Monotonically Increasing Economic Dispatch of Non-Monotonically Increasing GeneratorsGenerators
Block diagram of proposed program
References: Pictures from midamericanenergy.com and energyquest.ca.gov
Other ResourcesOther ResourcesNone required
Design ObjectivesDesign Objectives• Flexible program design• Well-commented program code• Comprehensive iteration scheme
Functional RequirementsFunctional Requirements• Provide best generator dispatch• Output iteration calculations
Design ConstraintsDesign Constraints• Five-minute limit on iteration run time• Expandable for future additional generating units• Clear box design enabling modifications of program• The software shall utilize Microsoft Excel as the interface
Measurable MilestonesMeasurable Milestones• End-product Design Dec. 08, 2005• Product prototype Jan. 23, 2006• Product testing Mar. 23, 2006 • Product documentation Apr. 10, 2006• Product demonstration Apr. 26, 2006
Hours per Task
50 4236
2047640
40
160
Project DefinitionTechnology Consideration and SelectionEnd-Product DesignEnd-Product Prototype ImplementationEnd-Product TestingEnd-Product DocumentationEnd-Product DemonstrationProject Reporting
Combine Solution Sets
Output Optimal Dispatch
Load User Defined Inputs
Solve for Non-Monotonically
Increasing Units
Solve for Monotonically
Increasing Units
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