MISO is not giving itself time to celebrate after FERC recently accepted its transmission cost allocation plan, promising more such work on long-term and interregional projects.

“We made it. We got across the finish line. After about three years of stakeholder discussion and a year and a half of FERC rejections, we did it,” MISO Senior Manager of System Planning Jarred Miland joked during the Regional Expansion Criteria and Benefits Working Group’s (RECBWG) teleconference Thursday.

MISO’s plan lowered the voltage threshold for market efficiency projects (MEPs) from 345 kV to 230 kV and eliminated the 20% postage-stamp allocation in favor of allocating full costs to benefiting transmission pricing zones. It also added two new benefit metrics based on whether a project can reduce dependency on the RTO’s transmission contract path with SPP or eliminate needs for other reliability projects. FERC approved the plan in late July. (See MISO Cost Allocation Plan Wins OK on 3rd Round.)

But the RECBWG’s work on transmission project cost allocation is far from over.

“I feel like it was time to take a nap, but then [Vice President of System Planning Jennifer Curran] kicked off expanded long-range transmission planning yesterday,” Miland said, referring to Curran’s announcement Wednesday to the Planning Advisory Committee that MISO will explore long-range transmission solutions — and may have some project recommendations as soon as next year.

The working group will likely forge new cost-allocation methodologies for any long-range transmission projects that may result. Several stakeholders asked when and how the group would approach the effort.

“We have to figure out what we’re talking about first,” Miland said in asking for patience. Long-range transmission discussions are continuing in MISO’s planning committees, and Miland said the RECBWG must wait to see what projects develop before it devises cost-sharing methods.

“It’s not baked yet; it’s not ready for primetime,” he said.

Miland also said the grid operator is now considering another filing to lower the voltage threshold on interregional MEPs with PJM from 345 kV to 230 kV.

That seemed to confuse stakeholders, who said the interregional project allocation voltage threshold was already lowered to 100 kV after a 2013 complaint at FERC by Northern Indiana Public Service Co. against the MISO-PJM interregional planning process.

Miland clarified that currently, the RTOs’ interregional economic projects between 100 and 345 kV are allocated to benefiting transmission zones based entirely on the original adjusted production cost metric. MISO is proposing to additionally use the two new benefits metrics to evaluate 230-kV+ MISO-PJM interregional projects.

“I think it would be a pretty simple filing to do,” Miland said. MISO’s rationale is that it would align both the RTO’s regional and interregional project evaluations, he said.

But Clean Grid Alliance’s Natalie McIntire argued that because FERC ordered a 100-kV threshold on MISO-PJM interregional projects, the RTO should also apply that to any benefit metrics.

Some stakeholders asked if MISO would also consider a filing applying the two new benefit metrics to economic projects with SPP.

“Frankly, we have not had any conversations around that,” Miland said.