By Amanda Durish Cook

CARMEL, Ind. — MISO last week said it will defer any initiative to account for planned and maintenance outages in capacity planning until it kicks off a broader discussion on overall resource availability sometime next year.

The RTO floated the idea of the initiative last month after observing an increasing number of intentional outages that occurred during periods of peak demand. (See MISO Seeks to Gauge Risk of Peak Season Planned Outages.)

But stakeholders are mixed in their support for accounting for the outages in forecasts for peak periods, MISO Resource Adequacy Coordinator Ryan Westphal said during a Dec. 13 Resource Adequacy Subcommittee meeting.

Instead of accounting for the outages in its mid-2018 capacity planning, MISO now hopes to implement the changes for the 2019/20 planning year. The RTO plans to roll the outage consideration into discussion about its seasonal capacity procurement proposal, which has been rebranded as “resource availability and need,” as planners have increasingly begun to think the answer to capacity issues may not lie in seasonal procurements but in something more granular.

RASC liaison Shawn McFarlane said MISO is now assessing the “hour-by-hour” availability of capacity resources instead of relying on a season-by-season basis of availability. The RTO plans later this month to release a white paper on resource availability trends throughout the year.

“We want to make sure we understand when resources are available, especially in light of the increasing maximum generation events since the 2016/17 planning year,” said MISO analyst Dustin Grethen.

Indianapolis Power and Light’s Ted Leffler noted that MISO once had a Real-Time Sufficiency Task Force that worked on outage-related forecasting issues but ultimately did not come up with a new forecasting process that included planned outages.

“We worked on this for about a year and a half before we gave up,” Leffler said. He urged MISO officials to review the old task force’s documents, if any of them survived.

MISO stakeholders have likewise cooled on defining seasonal capacity procurement requirements.

At an October RASC meeting, some stakeholders questioned the need for seasonal limits, noting that MISO’s emergency conditions in April and September were outside of the summer months, the result of poorly coordinated transmission outages.

NRG Energy’s Tia Elliott suggested that MISO might not need a seasonal definition of capacity at all if it decided to pursue its own transmission project to link its Midwest and South regions. Elliott also expressed exasperation at “being down this dirt road before and ending up in a puddle,” referring to MISO’s two-season capacity market proposal in late 2015 that eventually devolved into the proposal being scrapped to allow the RTO to conduct more research. (See “Seasonal Aspect Back in Conceptual Stage,” MISO Postpones External Zones Until 2019 Auction.)