2009 State of the Market Report
Load and Resources
In this section, we provide an overview of the supply and demand conditions in the Midwest ISO markets. We summarize load and generation within the Midwest ISO region and evaluate the resource balance in light of available transmission capability on the Midwest ISO network.
In delineating the Midwest ISO geographic boundaries, we confine our analysis to the participants in the Midwest ISO markets. There are more than 80 owners of generation resources in the Midwest ISO market footprint. This group includes large investor-owned utilities, municipal and cooperative utilities, and independent power producers.
For our analysis, we generally divide the Midwest ISO into four geographic areas. Three of the four are coordination regions that the Midwest ISO uses to operate the system. The final area is the WUMS area that has experienced a relatively high level of congestion historically. These regions are:
East — generally includes the Midwest ISO areas that had been located in the North American Electric Reliability Corporation’s (“NERC”) ECAR region;
West — generally includes the Midwest ISO areas that had been located in the NERC MAPP region;
Central — generally includes the Midwest ISO areas that had been located in the NERC MAIN region, but excluding MAIN utilities located in the WUMS area; and
WUMS — the Midwest ISO control areas located in the WUMS area. It is part of the East reliability region, but we examine it separately due to differences in transmission topology and historical congestion patterns.
These four regions should not be viewed as distinct geographic markets, particularly with respect to generation ownership concentration. Conventional concentration analysis in these regions does not allow one to draw reliable competitive conclusions. Accurate market power conclusions require analyses beyond calculating market share and concentration statistics. This is discussed at length in Section VI.
Our first analysis in this section summarizes 2009 load patterns throughout the Midwest ISO. The Midwest ISO is a summer-peaking region overall, although the northern areas in the West