By Amanda Durish Cook
CARMEL, Ind. — In what marked a first for the grid operator, MISO last week detailed its spring readiness and said there’s a small possibility of emergency conditions.
While the RTO expects to have adequate resources on hand to meet sometimes volatile demand, it might also have to rely on emergency operating procedures during what was once considered a calm shoulder period, stakeholders learned during a March 8 Market Subcommittee meeting.
“Projected spring transmission and generation outages show challenging but manageable outages, similar to recent years,” said Jeanna Furnish, MISO manager of resource planning and transmission studies.
MISO’s analysis shows a 25% probability it will need to invoke systemwide emergency operating procedures during the spring, but only if either loads or forced outages are higher than normal, Furnish said.
“My presence here isn’t to cause any alarm but to talk about … the realities of challenges that may exist on the system,” Furnish said.
Based on forecasts from the National Oceanic and Atmospheric Administration, the RTO is expecting a warmer-than-usual spring for MISO South and normal to above-normal precipitation in most of its footprint.
MISO said volatile spring loads that deviate from forecasts will require careful coordination of outages.
Furnish pointed out that MISO maintains a nonpublic member webpage called “Maintenance Margin” that keeps a monthly forward account of how many megawatts can be taken out of service without affecting reliability. The RTO uses the data to inform generators when it predicts outages will have an impact on reliability and will recommend alternative outage schedules.
Last year, high generation and transmission outages paired with unseasonably elevated loads in MISO South produced an early April maximum generation event, unusual for a shoulder season, prompting the RTO to call on load-modifying resources for the first time in a decade. The event prompted the Independent Market Monitor to call for MISO to have increased authority over approving maintenance outages. (See 4 LMRs Face Penalties after MISO Max Gen Emergency.)
Customized Energy Solutions’ Ted Kuhn asked if Maintenance Margin provided any indication that emergency conditions were imminent last spring.
“Was the Maintenance Margin showing a deficit, or did we just fall into a black hole?” Kuhn asked.
Furnish didn’t know but said MISO continues to work with stakeholders to enhance outage coordination, including developing reserves that can be available within 30 minutes and improving congestion management with PJM at the seams by swapping control of flowgates.
MISO did not venture a guess about the projected spring peak. The RTO is planning for a 126-GW summer peak load, which it predicts will require a 17.1% planning reserve margin. (See MISO Planning Reserve Margin Climbs to 17% for 2018/19.)
