ISO-NE last week shot back at renewable groups who have challenged its rules and claimed that gas-powered generators get preference, saying that their complaint with FERC should be thrown out (EL22-42).

The grid operator’s motion to dismiss filed Thursday comes a month after RENEW Northeast and the American Clean Power Association alleged that ISO-NE’s rules around capacity accreditation and operating reserves don’t adequately take into account the uncertainty of natural gas supply in the region. (See Renewable Groups Challenge Gas ‘Preference’ in ISO-NE Rules.)

Central to ISO-NE’s response is the fact that new rules are already under development.

FERC should dismiss the complaint “because it is an improper attempt to circumvent the New England stakeholder process and it invites the commission to impose a solution that reflects only complainants’ preferred outcome on their preferred timeline,” the RTO said.

ISO-NE is about to start work on a framework for resource capacity accreditation within the next few months, it said, an “enormously complex project with significant implications for the reliability of the New England grid.”

The project is budgeted to take two years, in line with ISO-NE’s proposed transition away from the contentious minimum offer price rule in its capacity market. The grid operator is also launching a day-ahead ancillary services project, which it says would be the “appropriate forum” for the renewable groups’ complaints about the reserve procurement process.

In asking FERC to toss the complaint, ISO-NE pointed to a previous case in California in which the commission dismissed a complaint seeking changes to CAISO’s market rules that were “directly related to market design issues [already] under review by [CAISO] as part of [a] revised market design proposal.”

ISO-NE also argued that the complaint should be dismissed on merit, saying that the region’s tariff explicitly contradicts the groups’ claims that gas generators have no obligations to report on their reserves or are excluded from fuel supply requirements. It also said that the relief proposed by RENEW and ACP is “unworkable.”

In comments on the FERC docket, several renewable and environmental advocacy groups have backed the complaint, while several generation companies have put their support behind ISO-NE.

The New England States Committee on Electricity and the attorneys general of Connecticut and Massachusetts said in comments that the changes proposed in the complaint are premature and that the issues of capacity accreditation and reserve procurement need more comprehensive treatment through the NEPOOL stakeholder process.