MISO is questioning whether its current loss of load standard remains the best method for establishing resource adequacy and initiated a daylong meeting with industry experts and regulators to probe alternatives.  

“The one-day-in-10 years resource adequacy criterion has a number of limitations, and many industry experts recommend change,” MISO Director of Strategic Initiatives and Assessments Jordan Bakke said in opening the Sept. 26 special teleconference.  

Bakke said MISO is exploring the concept of a more comprehensive resource adequacy benchmark. He said MISO needed a “natural, long-form discussion about what’s needed going forward.”  

The grid operator has hinted in public meetings that it might turn to conditional value at risk, loss of load hours or expected unserved energy as possible new measures of resource adequacy risk.  

Bakke said any potential solution MISO might put forward will be developed in partnership with its regulatory and stakeholder community. He emphasized that MISO doesn’t have a preferred approach, timeline or proposed tariff revisions. He said MISO plans to draft a road map for evaluating new standards.  

“We don’t know when and if something will change,” Bakke said.  

Derek Stenclik, representing Energy Systems Integration Group, said he thought MISO is doing the right thing by raising the possibility for change among its stakeholder community.  

He said as far as “setting the threshold for an acceptable level of risk,” MISO needs to land on something transparent and economic.  

Stenclik said MISO should begin by quantifying the size, frequency and duration of outages. MISO also should incorporate a “suite of reliability metrics,” he said, putting more emphasis on expected unserved energy. He said MISO’s move to an energy-limited system heavy on renewables necessitates multiple metrics.  

He said, for example, MISO could use a combination of its current 0.1 days/year loss of load expectation in addition to a 0.3 hours/year loss of load hours analysis and a 1,000 MWh/year expected unserved energy, as PJM has considered.  

“We don’t have to have just one,” Stenclik said.  

Zach Ming, of energy consultancy E3, pointed out that ERCOT recently announced it will use a three-pronged reliability standard that marries the usual one-day-in-10-years standard with a 12-hour limit on outage duration and a 19-GW limit on the magnitude of outages.  

EPRI’s Aidan Tuohy also recommended reducing reliance on a single measurement.  

“Adequacy exists on a spectrum and should not be a binary choice,” he said.  

Tuohy said while LOLE conveys the expected number of days when loss of load occurs, it doesn’t capture the magnitude of the loss. MISO likely needs a more detailed look, Tuohy said, where it considers outlier events, assessing risk by month or hour of day and describing involuntary load-shedding events.  

“More high-impact, low-probability events” are on the way, Tuohy predicted.  

Meanwhile, the Organization of MISO States is positioning itself to have a voice in MISO resource adequacy criteria. 

OMS Executive Director Tricia DeBleeckere said regulators have a collective awareness that the standards need to shift. She reminded attendees that states have resource adequacy jurisdiction and want a “key seat at the table” when designing new criteria.  

DeBleeckere said the 0.1 days/year standard has been in use so long that changing it will be a “huge initiative.”  

“A big thing for OMS is who is going to be making the call when these changes are made,” she said, adding that OMS’s support of MISO’s road map will hinge on how much MISO includes state regulatory standpoints.  

DeBleeckere said though no one can develop a perfect reliability standard, a replacement should be data-driven and not “overcorrect” acceptable levels of risk.  

OMS President and Iowa regulator Josh Byrnes has said state regulators will work on a guiding principles document on resource adequacy standards. It will focus on ensuring states’ leadership on a new reliability standard and allow enough time to understand what’s expected and to meet whatever threshold is set.  

At a Sept. 12 Organization of MISO States board meeting, North Dakota Public Service Commission Julie Fedorchak said states should do more to steer discussions on resource adequacy benchmarks.  

“It feels like OMS should enter this area … and take a more leadership role in this resource adequacy metrics discussion,” Fedorchak told other state regulatory staff.  

Byrnes said MISO “probably needs to do a better job” engaging state regulators if it suggests crafting a new resource adequacy target.  

Michigan Public Service Commission Chair Dan Scripps said states “absolutely” should be at the center of those discussions because the “political reality” is state regulators receive calls from customers and governors when outages occur.  

“No one wants to hear that, ‘Oh, that was our one event in 10 years,’” Scripps said.  

Bill Booth, a consultant to the Mississippi Public Service Commission, said he thought NERC, not MISO or state commissions, should establish a resource adequacy standard.  

“Do you want to have a MISO standard and a PJM standard and an SPP standard?” Booth asked rhetorically.  

MISO again will discuss reliability standards at its Oct. 9 Resource Adequacy Subcommittee meeting.