By Amanda Durish Cook

CARMEL, Ind. — After two years, MISO and SPP have negotiated a memorandum of understanding to address overlapping congestion charges, implement a small interregional project type and swap flowgate control to account for power flows.

RTO officials say the MOU, which borrows elements from MISO’s coordination efforts with PJM, provides market-to-market specifics where the joint operating agreement is vague. The document won’t result in major changes in coordination, officials said.

The MOU addresses exchanging control of market flows, correcting errors in firm-flow entitlements, studying the impacts to entitlements when facility ratings are changed, capping entitlements at the security operating limit and making market-to-market hold-harmless reimbursements. (See “MISO, SPP Agree to M2M Improvements,” SPP-MISO Briefs.)

Complex Topics

SPP Director of Interregional Relations David Kelley said the RTOs have been working to improve M2M coordination since early 2015. “These are some very complex topics that often involve months or years of negotiations,” he said.

Staff say the memo is meant to target problems the RTOs have experienced since the start of the M2M process, including ineffective real-time congestion management on flowgates and errors in settlement calculations. Kelley said the memo documents the RTOs’ “common agreement” on how to handle M2M issues. “There were honestly some different interpretations of the JOA,” Kelley said at a May 31 meeting between the two RTOs at MISO’s headquarters, the first JOA meeting in a year. MISO’s Jeremiah Doner said that given the complex interregional goals the RTOs have laid out, another JOA meeting would be scheduled soon.

Kelley said the memo’s objectives aren’t written out verbatim in the JOA, but the “intent” of the memo is in the JOA.

Ron Arness, of MISO’s seams management division, said a few of the items outlined in the MOU, such as swapping control of flowgates, will require JOA changes. Arness said the agreement still needs approval from representatives of both RTOs’ legal departments and executive leadership.

Kelley said the document won’t necessarily be filed or become public. He said the RTOs want to execute the MOU in the next few weeks and file with FERC a revised JOA to allow limited resettlements during the summer.

Swapping Flowgate Control

“The longest pole in the tent is the market flow control change. We have software being delivered for that,” added MISO Director of Forward Operations Planning Kevin Vannoy.

The memorandum allows MISO and SPP to use an alternative flowgate control at certain times when power swings are significant, so predominant market flow dictates relief control on a flowgate, and not solely which RTO has monitoring control, Kelley said.

There have been situations in the past where MISO has had 95% of the flow on a flowgate but SPP still controls it, and it’s difficult to manage, Kelley said. He added that the RTOs will only swap control of flowgates when both agree that it’s the best course of action, either resulting in better price convergence or better congestion constraints. All instances where the RTOs trade monitoring roles will be reviewed after-the-fact.

At MISO’s last Board of Directors meeting in March, MISO Market Monitor David Patton appealed for MISO, PJM and SPP to become more active in transferring monitoring of constraints. (See Tornadoes, Wind Generation Drive MISO Tx Congestion.)

Resettlements

MISO and SPP will also form a technical committee by early October to address M2M issues and resettlements, but the RTOs said they will not retroactively provide resettlements more than six months prior to the MOU except for three 2015 cases, in which SPP will refund MISO more than $600,000.

Kelley said the RTOs will not pursue any other resettlements. “While we would love to chase down every penny, we don’t think that’s effective. We don’t think that’s a good use of your dollars,” Kelley said.

Going forward, when market participants dispute settlement amounts in the M2M process, Kelley said they will have to fill out a standardized form for RTO staff to review.

Stakeholders asked if the MOU’s resettlement provisions will extend to overcharges on pseudo-tied resources from double-counting congestion. Vannoy said those charges are not in the scope of the memo, and the issue will probably be handled with FERC-ordered refunds.

Adam McKinnie, chief utility economist for the Missouri Public Service Commission, asked whether the MOU is permanent or will be continually revised depending on future resettlements.

“Is this going to be some interminable, shifting document that we’re never quite sure of?” he asked.

Kelley said SPP’s resettlements are discussed at monthly Seams Steering Committee meetings.

“You’re not my problem as much as the other RTO in this room,” McKinnie said.

“Shots fired,” Kelley jokingly replied.

Arness said MISO presents resettlement payments exceeding $250,000 at the Seams Management Working Group, but McKinnie countered that not all seams issues are routed through the group.

“I know where to go when there’s a seams issue at SPP. … It’s frequently difficult to follow seams issues at MISO,” he said.

Flowgate Management Criteria

MISO and SPP staff also revealed new flowgate management criteria in the memo and said M2M flowgates will be removed when a non-monitoring RTO does not have at least a 5% forward or dispatchable 5% reverse impacts. Flowgates can be reinstated once they pass the 5% threshold.

Vannoy said he imagined that the RTOs would address which flowgates are used in their weekly M2M staff meetings. A more formal review to remove flowgates will take place at monthly meetings between SPP and MISO staff.

Overlapping Congestion

The RTOs are currently monitoring interface pricing and are asking for stakeholder advice on how to reduce their overlapping congestion charges after a joint analysis.

The RTOs analyzed price incentives using current interface definitions, comparing them to “ideal” incentives with no congestion overlap. An analysis of binding constraints in 2015 and 2016 showed congestion pricing was 1.85 times the ideal, said Dustin Grethen of MISO’s market evaluation design group. Vannoy said the RTOs are over-incentivizing impacts of transactions, paying 85% more than necessary when congestion pricing is used.

The RTOs are considering resolving the modeling problem using either a MISO Monitor-endorsed solution in which the monitoring RTO prices the entire path from the non-monitoring RTO area with zero payments made by the non-monitoring RTO, or use a common bus interface definition in which each RTO sets its interface price “relative to a common set of interface points,” the solution MISO and PJM elected to use. (See PJM, MISO Go Quiet on Pseudo-Ties; Reach Interface Pricing Accord.)

SPP’s Tanzila Ahmed said the RTOs don’t have to use the common interface definition just because it worked for PJM and MISO. “We’ll possibly see if there are other solutions. These two solutions might not work perfectly with SPP and MISO.”

MISO and SPP currently charge or credit congestion for the entire path of pseudo-ties, even when the path crosses into another balancing authority.

The RTOs are also considering varying levels of rebates depending on whether they adopt a common bus definition and the eventual scheduling of pseudo-ties in the day-ahead market to address the double-charging problem, Vannoy said. They’re also still analyzing pseudo-tie data and the RTOs’ separate modeling methods and have not yet arrived at any solution, he said.

Replacing Freeze Date, Implementing TMEPs

As with PJM, MISO is aiming to replace the freeze date by which firm-flow entitlements are calculated with SPP with four tranches based on generator in-service date, and implement a targeted market efficiency project (TMEP) type for cost-effective and congestion-relieving seams projects that might otherwise be overlooked because of their low cost and small size. (See “Four Categories for Freeze Date,” MISO-PJM TMEP Projects Drop to Five.)

MISO and PJM filed to implement TMEPs in their JOA on Dec. 30 (ER17-721); the two have identified $17.25 million worth of upgrades in five TMEP candidate projects. By September, both RTOs hope to finish evaluation of TMEP candidates and ask for board approvals by the end of the year.

MISO and SPP could begin drafting JOA and Tariff language to create the project type while looking for small project candidates that could relieve historical congestion on the seam, said Davey Lopez, MISO adviser of planning coordination and strategy. He said the RTOs could determine regional and interregional cost allocation throughout 2018 and have board-approved projects ready for construction by early 2019.

Entergy’s Yarrow Etheredge said she was apprehensive that the RTOs will begin selecting projects before the JOA language is finalized. She wondered if MISO and SPP had considered that their TMEP would have different criteria than a MISO-PJM TMEP. “The needs on the PJM-MISO seam are so different than the needs on the SPP seam, so an entirely different process could be warranted,” she said.

Lopez said the RTOs built enough time into the project creation and selection timeline for multiple rounds of stakeholder reviews. Kelley also said there is room for “commonalities” between the two types of TMEPs, and SPP stakeholders have signaled that there is appetite for a similar TMEP project type creation.

McKinnie asked if MISO and SPP assume that no TMEPs would be opened to competitive bidding because of the short timeline. MISO engineer Adam Solomon said MISO expects that “99%” of TMEP project candidates — including all five current MISO-PJM TMEP candidates — will be upgrades to existing facilities and therefore not open to competitive bidding.