MISO membership has called for modernized market rules for energy storage that can capture its chameleon-like roles.

This time, members at a Feb. 4 Advisory Committee teleconference suggested conversation starters to begin drafting rule changes.

Clean Grid Alliance Executive Director Beth Soholt said there are more uses for storage “than MISO is currently acknowledging or has rules to implement.”

“Storage is very much posed to make an impact in MISO and help with the challenges MISO sees coming,” Soholt said.

Multiple members agreed storage is at once a market resource, transmission asset, load when necessary or a microgrid component and that rules should reflect those capabilities.

South Dakota Public Utilities Commissioner Chris Nelson said he agreed storage is the “Swiss Army knife” of the grid. But he added that commissioners must conclude that storage solutions are cost effective before approving them.

“Bottom line, that’s what we’re looking at,” Nelson said.

However, Fresh Energy’s Mike Schowalter said for storage to be cost effective, MISO’s rules need to be flexible enough for storage to switch duties.

“We hear that it’s a Swiss Army knife, but if it’s not valued in the market for these things, then it’s not going to benefit ratepayers,” Iowa Utilities Commissioner Sarah Martz said.

“MISO’s rules are not compatible for merchant services,” Pelican Power’s Tia Elliott added.

Elliott pointed out that MISO is the only RTO that requires storage to secure and pay for transmission service to charge from the grid, regardless of whether the charging is done under MISO dispatch.

Elliot said storage can interconnect quickly without placing reliability at risk and could help with large load integration. She suggested MISO members meet to discuss where they agree on the resource’s monetizable capabilities.

Schowalter said MISO could start by listing what storage is able to do that typical resources cannot.

“Storage can respond in 16 milliseconds — very fast,” he said.

Schowalter said MISO’s pricing framework and tools were designed long enough ago that MISO and members should examine what’s outdated.

“Especially, as we add more renewables, storage is going to play a key role,” he said, encouraging MISO members to imagine the system and what it would need in 2045 with majority renewable penetration.

“We really can’t wait for that to happen to see what happens and the rules we’ll need in place,” Schowalter said.

“We can do it; we just have to find the will,” Soholt said.