Congestion Management in a Market Environment

2nd CIGRE / IEEE PES International Symposium San Antonio, Texas

October 5, 2005Kenneth W. Laughlin

PJM RTO on January 1, 2005

Generating Units 1,400Generation Capacity 170,807 MWPeak Load 131,600 MWAnnual Energy 648,000 GWhTransmission Miles 55,000Area (Square Miles) 186,000

Customers 21 MillionPopulation Served 50+

MillionStates (+ D.C.) 13 states +

D.C.

Generating Units 1,400Generation Capacity 170,807 MWPeak Load 131,600 MWAnnual Energy 648,000 GWhTransmission Miles 55,000Area (Square Miles) 186,000

Customers 21 MillionPopulation Served 50+

MillionStates (+ D.C.) 13 states +

D.C.

PJM RTO (January 1, 2005)PJM RTO (January 1, 2005)

PJM - Full Service RTO• Control Area Operator• Transmission Provider • Market Administrator• Regional Transmission Planner • NERC Reliability Coordinator

Congestion Management - Operations

• System Operators must address all events, all constraints – reliability, economic and natural

– Perform future studies to determine safe operating conditions

– Perform day-ahead studies of expected operating conditions to test its operating plan

– Operate in real time according to day ahead plan

Congestion Management - Tools

• Real-time assessment of power system• Real time alarm systems for real and

contingency overloads• Calculation of sensitivity factors of

generation flows on the transmission system

• Determination of redispatch options to maintain reliable operations

Congestion Management - Tools

• Security-constrained, economic dispatch

• Determine the economic value of generation in real time at every node on the system based upon:– transmission system parameters– generation loading– transactions

Congestion Management - Methods

• Transmission Line loading Relief (TLR)– Identify flowgates (frequently constrained

segments of the transmission system)– Determine generation impact on flowgates– Monitor flowgates and generate alarms for

overload conditions (manually)– Curtail regional transactions impacting

loading on flowgates based upon priority of transmission service

Congestion Management - IT

• Math is the same as it was in 1970

• Difference is the technology and speed of computing

• Improvement is the scope of options and the size of the system that can be monitored and priced in real time

• PJM produces a system dispatch every five minutes for an 87,000 MW peak load system and reports 10,400 prices with a 1 minute time lag.

Congestion Management - Experiences

• Market to Non-Market– identify flowgates regionally– identify and agree to acceptable flows on

flowgates imposed by each region– if flowgate limit is exceeded issue alarm– regions without LMP will curtail transactions to

respect flowgate limits– regions with LMP will redispatch generation to

respect flowgate limits

• Market to Market– Identify flowgates and level of acceptable

flows by each region on each flowgate

– If the reliability limit of the flowgate is exceeded, all regions impacting the flowgate will redispatch generation to respect the flowgate limit

Congestion Management - Experiences

Congestion Management - Symposium

Symposium Sessions

• Congestion Management – Operations• Congestion Management – Methods• Congestion Management – Experiences• Congestion Management – Information Technology

Congestion Management

Market Role

• Markets (in North America) Link• Reliability (defined by standards – North American Electric

Reliability Council)

• Exercise of Free Market opportunities

Congestion Management

LMP Role

• Locational Marginal Pricing is signal used to Link• Reliability • Exercise of Free Market opportunities• Generation Construction

Congestion Management

Industry Major Challenge

• Signal(s) to Incent Transmission construction

Congestion Management

Symposium Participant Challenge

• Actively participate in Sessions• Communicate ideas• Resolve questions• Use information

• To define academic research• To share • To foster industry development