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California's Wholesale Market Design and Operations

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A “seams issue” is a barrier or inefficiency resulting from either:

  1. differences in market or tariff rules and designs, or
  2. operating and scheduling practices that inhibit or preclude the ability to economically trade capacity, energy, and ancillary services across control area boundaries.

Seams issues should be mitigated, as they can lead to inappropriate price signals, gaming opportunities, inefficient utilization of scarce transmission resources, or reliability impacts. Seams impact a number of entities across the western states region and are best resolved regionally rather than through individual transmission providers or market operator stakeholder forums.

This “regionalization” of dialogue requires a broad forum for investigation and resolution of seams operating impacts caused by differing practices of various market or power systems. Such a forum should identify issues that inhibit regional coordination and recommend solutions  to assure that differences in the manner in which neighboring control areas operate do not unnecessarily impede efficient competitive electricity markets or the reliability of the Western Interconnection.

Toward this goal, the CPUC actively participates in the Seams Issues Subcommittee (SIS) of the Western Electric Coordinating Council (WECC) to represent the interests of the California ratepayers.


Last Modified: 5/6/2008

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