Road Map

Each of the subregions have some risk in their areas when they are studied individually. However, as discussed in the Margin section, at WECC, we study risk before and after imports. One of the greatest benefits of the Western Interconnection is its geographic diversity as it relates to demand and resources. When one part of the interconnection is experiencing peak demands, other areas may not be. While resources may not be available in one subregion due to weather, fuel, etc., other subregions may have plenty of resource availability. It is important in resource adequacy to consider each subregion's ability to import energy from other subregions to cover the hourly risk in its system.


Transfers are available for most hours in which the expected margin falls below the threshold margin.

These charts show how much energy a subregion can import from the other subregions annually, monthly, and hourly. If you select CAMX, for example, you will see the imports only come from the other four subregions. Because most of CAMX's connections are with the NW and SW regions, most of its imports come from those two. Only a small amount of imports come from the other two regions.

The monthly breakout and hourly graphs show shapes similar to the hours of risk from the previous section. This is because these are the hours in which the CAMX subregion will import power to alleviate risk.

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Clicking a region on the map will change the charts to show that area's information. Clicking the same area again will switch the charts back to the overall Western Interconnection results.