Early Coal Closures Could Spell Trouble for Grid Reliability

By Rachel Dawson

The Northwest Power and Conservation Council regularly assesses the adequacy of our region’s power supply using a loss of load probability (LOLP). This measure informs us that power supply is not adequate if 5% or more modeled simulations show insufficient generating capacity at any time in a given year.

Due to the early closure of Boardman and Centralia 1 coal plants in 2020, the Northwest is projected to not meet this standard by 2021. The probability of a future inadequate load capacity increases to as high as 26% if Wyoming’s Jim Bridger 1 coal plant closes in 2023. To put this in perspective, the loss of load probability was expected to climb to 24% by 2003 after the 2001 energy crisis occurred.

This crisis was due in part to an unexpected decrease in hydroelectric power. It seems that utilities in the region have not learned their lesson, as they plan on replacing the coal plants with even more unreliable wind power and costly storage systems.

Advocates for these plants’ early closures must demonstrate that doing so will not damage grid reliability or increase ratepayers’ power bills. So far, they have not met that test.

Rachel Dawson is a Policy Analyst at Cascade Policy Institute, Oregon’s free market public policy research organization.