DFW AIRPORT, Texas — SPP’s Resource and Energy Leadership (REAL) Team last week marked the one-year anniversary of its formation with yet another discussion of resource adequacy issues and the various metrics used to determine a reliability standard. 

But not to worry. Major developments are on the horizon. 

“The bigger stuff is coming later,” said SPP’s Casey Cathey, senior director of grid asset utilization, following the Feb. 21 meeting. 

That would be the winter planning resource margin (PRM) and a reliability standard based on expected unserved energy (EUE). However, it may take time. 

“I think we need some time to bake in more of an understanding about the interrelationship between EUE and the fuel mix, as well as the load changes,” Cathey said. “We do need to work towards an accelerated standard, but we’ve never enforced an EUE limit before. It’s always been PRM. As we’re continually seeing the fuel mix change and the loads are also under a lot of scrutiny, with more resources that are underperforming and more extreme events, I think the fear is to put a standard without it being potentially well thought out could be extremely costly.” 

To ease that fear, the REAL Team contracted last year with firms 1898 & Co. and Astrape Consulting to conduct a future resource mix study. The study focused on five- and 10-year projections for PRM and renewable resources’ effective load-carrying capability values as providing better forward-looking information than the standard loss-of-load expectation (LOLE) studies. 

It also considered EUE as a new metric, given resource adequacy’s shift from “capacity adequacy” to “energy adequacy.” SPP staff said they have found a divergence in EUE and LOLE as the system evolves more toward an “energy-limited” resource portfolio. 

The study found the existing 0.1 LOLE reliability target continues to contribute to an increased EUE and “unacceptable reliability” and that as renewable capacity increases, the winter season becomes dominant. Implementing reliability metrics separated by season helps meet the annual LOLE/EUE target, it said. found the existing 0.1 LOLE reliability target continues to contribute to an increased EUE and “unacceptable reliability” and that as renewable capacity increases, the winter season becomes dominant. Implementing reliability metrics separated by season helps meet the annual LOLE/EUE target, it said. 

However, the study found a last-in allocation methodology “may allocate more accreditation than appropriate to certain technology types due to synergies between resources. It said more studies are required to confirm the appropriate level of a normalized EUE as a reliability standard. 

“We have a natural breakdown that winter events are longer, deeper and they have more amounts of energy per event than you do in the summer,” 1898’s Brian Despard said. “If you add more renewables, you’re shifting from summer events to winter events and there’s naturally more unserved energy in the winter. So, we have to install a standard that says, ‘Let’s keep unserved energy the same instead of keeping the number of events the same.’ We’re going to have a secondary and complementary requirement that says, ‘I will get a credit for the ability to maintain those standards as well.’” 

The REAL Team will continue its discussion of the PRM and EUE metric when it gathers at SPP’s headquarters in Little Rock, Ark, March 22. 

“That’s March Madness,” said Kristie Fiegen, chair of both the REAL Team and the South Dakota Public Utilities Commission and an apparent fan of college basketball’s annual postseason tournament. 

Still, the meeting will go on. 

“More education is needed across the board for members, for the Regional State Committee, for REAL,” Cathey said. 

The REAL Team reports to the RSC, which is composed of SPP state regulators. Also, it is working in tandem with the Supply Adequacy Working Group (SAWG) and the RSC’s Cost Allocation Working Team. 

“We’re kind of working to educate on the EUE, but to also help that education form how we might best establish our very first separate winter planning reserve margin,” Cathey said. “Even though we don’t have a standard — and this is what’s a little bit confusing — we still understand that we shouldn’t just let EUE be this massive number. We have to use the data from the loss-of-load expectation study to best inform how we balance the risk between winter and summer for upcoming 2026 binding season.” 

The REAL Team directed SAWG to consider EUE associated with an LOLE metric to determine winter and summer PRMs, recommend an EUE standard, and place the expectation of that effect on the 2025 LOLE study.  

Evergy’s Colton Kennedy, SAWG’s chair, agreed that more education and analysis is needed.   

“There’s a separate conversation around what [we] are establishing as a region for an EUE standard. I think honestly, we don’t need that to set the PRM, to recommend PRM,” he said. “I think we know that there are gaps. We know that the EUE is something that needs to be incorporated into the target. I don’t think we have enough information to say this is the appropriate risk tolerance for this region.” 

Separately, the team approved a tariff change (RR605) intended to clarify resource availability expectations for both the summer and winter seasons. The measure adds a definition of authorized outages and more requirements for availability during the two seasons when not on an authorized outage, and it clarifies when load-responsible entities and generation owners should submit resource adequacy capacity to meet their requirements. 

“It’s not the most complicated policy, but it’s fairly important. If we didn’t do it, we will be shooting ourselves in the foot,” Cathey said. 

The revision’s language is seen as meeting FERC’s expectation that SPP consider expedited proceedings for any future filings on the winter season RA requirement. The commission in November rejected the grid operator’s first attempt at a winter resource adequacy requirement; the RTO plans to refile the requirement, nonbinding until the 2026-27 winter, in April. (See “FERC Rejects Winter Requirement,” ‘Therapy Session’: SPP REAL Team Reviews Draft LOLE Study.) 

The REAL Team also endorsed a pair of initiatives by staff and stakeholders: 

• • The Market Working Group’s development of potential availability market constructs and other incentive-based mechanisms. The MWG explored five options before determining that, based on staff’s evaluation, a performance credit mechanism (PCM) similar to ERCOT’s and an energy availability market would provide the largest economic and reliability benefits. The group is monitoring ERCOT’s PCM development process and will reevaluate the need for additional mechanisms once resource adequacy policies are implemented and evaluated. 
  • Staff’s pursuit of a price-formation policy that dispatches the system based on the true obligation and prices the system during a scarcity event using the obligation without the effect of load shed and emergency energy assistance. Staff plans to secure approval from stakeholders, regulators and the board in April and May, and then take the revision request to the same bodies in July and August.