Functionalities GEMS

Market Price Simulator (MarSiTM)

Functionalities of Modules

Global Energy Market Solutions (GEMS), Inc.

2008

© GEMS, Inc. Functionalities of MarSi 1

A. Introduction to MarSiTM

What is MarSiTM?

MarSi is a simulation software package for the actual operation of integrated electricity and natural gas systems under a wide range of operating conditions. MarSi is developed by Global Energy Market Solutions (GEMS), Inc. and runs on a single Windows-based computer. MarSi can optimize security constrained short-term and long-term generation scheduling, resource allocation, and integrated generation and transmission maintenance scheduling. MarSi can be used in an electricity market environment or by a vertically integrated utility for assessing the power system operation strategies and identifying system bottlenecks that stem out of the interdependency of electricity and gas infrastructures.

Modules of MarSiTM

♦ AC Security-Constrained Unit Commitment (SCUC) ♦ AC Security-Constrained Optimal Power Flow (SCOPF) and Settlement


Applications

♦ RTOs/ISOs implement MarSiTM for day-ahead market clearing

♦ Integrated utilities apply MarSiTM for daily generation scheduling and gas allocation

♦ TRANSCOs implement MarSiTM for market price simulation and scenario analyses

♦ GENCOs implement MarSiTM for simulating bidding strategies in different markets

Features ♦ Unit commitment with AC network constraints (line flows and bus voltages)

♦ AC congestion management which considers various types of load shedding schemes for a group of buses with several types of load shedding contracts

♦ Detailed models for wind, thermal, combined-cycle, fuel-switching, cascaded-hydro and pumped-storage units

♦ Detailed models transmission lines including phase shifter and tap changing transforms

♦ Detailed models for gas network management

♦ Monte Carlo simulation of generation and transmission outages

♦ Detailed models for multiple fuel and emission constraints

♦ Includes a complete set of portable input/output databases and files

♦ Runs on a personal computer with Windows operating system

♦ Includes a users’ manual with several examples which will help users familiarize themselves with the software’s features

Samples of MarSiTM Outputs and Analyses ♦ Unit commitment and MW dispatch for each generating unit ♦ LMP calculations and congestion management ♦ LMP-based market analyses ♦ Transmission flow analyses for a set of contingencies ♦ List of binding transmission lines ♦ Cost of congestion management for the given contingencies ♦ Impact of unit commitment strategies on transmission congestion and FTR analyses

Input and Output Data MarSiTM uses an integrated database, individual input/output databases for each module.

B. Functionalities of MarSiTM

Functionalities of MarSiTM modules are given next.


B.1 AC Security-Constrained Unit Commitment (SCUC)

What is SCUC? • SCUC calculates unit commitment schedule for the optimal allocation of generation

resources with full AC transmission security constraints while meeting the various prevailing unit and system level constraints.

• The output of SCUC will provide a feasible commitment schedule for calculating SCOPF (See SCOPF next).

Applications ♦ RTOs/ISOs implement MarSiTM for day-ahead market clearing

♦ Integrated utilities can apply MarSiTM for daily generation scheduling and gas allocation

♦ GENCOs implement MarSiTM for price forecasting in different markets

Input Data ♦ Generation Unit Data

Forced outage rates

Scheduled outage parameters

Wind and Pumped-storage hydro units: Wind unit characteristics, water-conversion coefficients, volume limits, initial and terminal volumes, discharge limits, cycle efficiency

Thermal units: generation limits, incremental heat rate curves, minimum up/down times, ramp up/down rates, start-up cost characteristics, multiple emission constraints, multiple fuel constraints, must on/off, and other operating constraints

Combined-cycle units: generation limits, incremental heat rate curves, minimum up/down times, ramp up/down rates, start-up cost characteristics for each CT/ST configuration, multiple-emission constraints, multiple-fuel constraints, must on/off, and other operating constraints

Fuel switching units: heat rate curve for each possible fuel, generating capacity, minimum up/down time, ramp up/down rates, start-up cost characteristics for each fuel type, fuel and emission constraints, must on/off conditions

Cascaded hydro units: topology, water-conversion coefficients, volume limits, initial and terminal volumes, discharge limits, natural inflows, spillage, delay times

♦ System level Data

Hourly load forecast Spinning reserve requirements Operating reserve requirements Interruptible loads (cost and schedule) Fuel constraints (for all fuel types and individual units) Regional emission limits


♦ Transmission Network Data

Transmission forced outage rates Transmission flow limits Transmission line parameters Scheduled outage parameters Phase shifting and tap changing transformer parameters

♦ Gas network Data

Each pipeline is modeled by several firm and interruptible gas contracts Each pipeline may feed several units / generating plants Location of pumping stations and pipeline distances (units further down can only

burn a percentage of the total gas in the pipeline) Daily and hourly gas limits for each pipeline, each sub-area, each plant, and each

unit

Output Data ♦ Short term unit commitment schedule for each generating unit ♦ Hourly fuel allocation (gas or oil) for each unit with fuel-switching capabilities ♦ Short-term gas consumptions per pipeline, gas contract, sub-area, plant,

generating unit

Features ♦ SCUC minimizes system operating cost or bid-in cost while enforcing unit level,

transmission flow, bus voltage, gas network constraints. ♦ SCUC adopts the state-of-the-art mixed integer programming (MIP) approach for better

and robust solutions ♦ Direct enforcement of network security constraints instead of relaxation as in

Lagrangian relaxation approach ♦ Case comparison capability


Input sample: Thermal Unit

Input sample: Fuel Switching Unit


Output sample: Hourly Unit Commitment

Case comparison capability


B.2 AC Transmission Congestion Management and Settlement (SCOPF) What is SCOPF?

• SCOPF is for the AC security-constrained optimal power flow solution. • SCOPF provides the optimal dispatch for committed generators. • SCOPF provides optimal allocation of ancillary services as well as energy for

each participant in the system/market.

Applications ♦ Security-constrained economic dispatch ♦ Optimal congestion management ♦ Market settlement

Input data ♦ Congestion Management

Number of Scheduling Coordinators GENCOs data DISTCOs data TRANSCOs data

♦ Market Settlement Transmission usage charges GENCOs data DISTCOs data TRANSCOs data

Output data ♦ Congestion Management

Optimal generation dispatch of individual generators Ancillary services output of individual generators Cost of congestion management for given contingencies LMP values List of transmission lines binding at maximum capacity Impact of unit commitment strategies on transmission congestion Impact of generation and transmission outage schedules on congestion cost

♦ Market Settlements LMP-based market settlement



Individual unit generation dispatch

Hourly Generation Dispatch for all units


Locational marginal price (LMP), market clearing price (MCP), Unit marginal price (UMP)

Hourly Gas Allocation


C. References

1. M. Shahidehpour and M. Marwali, Maintenance Scheduling in Restructured Power Systems, Kluwer Publishers, May 2000

2. M. Shahidehpour and M. Alomoush, Restructured Electrical Power Systems, Marcel Dekker Publishers, June 2001

3. M. Shahidehpour, H. Yamin and Z. Li, Market Operations in Electric Power Systems, John Wiley and Sons, March 2002

4. M. Shahidehpour and Y. Wang, Communication and Control in Electric Power Systems, John Wiley and Sons, March 2003

D. GEMS President Mohammad Shahidehpour is the President of Global Energy Market Solutions (GEMS), Inc., a consulting company in the business of developing and licensing software packages with specific application to the operation and management of electricity grids. He has served as consultant for the electric power industry and completed numerous technical projects funded by federal agencies and private power companies. The partial list of sponsors includes EPRI, DOE, NSF, DOD, Calpine Corporation, KEMA Consulting, Siemens, Amoco, Perot Systems, Open Access Technologies, as well as technical projects in Argentina, China, Jordan and Indonesia. Several of his software products are installed in utility companies worldwide by energy management system vendors.

He is the author of 300 technical papers on electric power systems operation and control, and four books on electricity restructuring. Dr. Shahidehpour is a Fellow of IEEE and has received several technical paper awards and outstanding working group awards for his contributions to power engineering.

He was the recipient of the Edison Electric Institute's Outstanding Power Engineering Faculty Award. E. Contact Mohammad Shahidehpour Global Energy Market Solutions, Inc. 225 Fiala Woods Court Naperville, IL 60565 (630) 308-GEMS


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