Gas Constraints

NYISO briefed the New York State Reliability Council Executive Committee (NYSRC EC) on an upcoming white paper to propose updates to the ISO’s resource adequacy modeling, including a recommendation to use a tiered load-based approach to estimate gas availability during the coldest winter days. 

Slated to be released by the end of the first quarter, the white paper comes in response to findings by NYISO’s Market Monitoring Unit, Potomac Economics, which found that eastern New York faces significant gas availability issues during peak cold conditions due to regional pipeline constraints. 

Con Edison’s Howard Kosel, the new chair of the NYSRC’s Installed Capacity Subcommittee (ICS), told the EC that NYISO is likely to recommend incorporating a tiered methodology based on load levels in its winter RA modeling to determine gas availability. This approach would assume no gas availability at loads exceeding 26,000 MW.  

The recommendation is based on Potomac’s observation that constraints in eastern New York during the coldest peak winter days were not being accurately modeled. Consequently, the ISO’s RA modeling during these periods was undervaluing certain generators and failing to anticipate the necessary level of gas procurement before peak winter days. 

The ICS will track the ISO’s progress and plans to share the white paper’s findings with the EC once published.  

PRR-151

The Reliability Rules Subcommittee (RRS) also briefed the EC about comments received on Proposed Reliability Rule 151 (PRR-151), which includes suggestions for adjustments to attestation requirements and the introduction of exemptions for evolving technologies. 

The NYSRC developed PRR-151 to address gaps in NYISO’s current interconnection criteria for inverter-based resources (IBRs) and establish standardized rules for IBRs larger than 20 MW. The committee endorsed industry comments on PRR-151 late last year. (See NY Reliability Council OKs Interconnection Standards for Large IBRs.) 

AES Clean Energy, Ørsted, GE and Alliance for Clean Energy New York submitted comments, aiming to ensure PRR-151 remains flexible and does not hinder the integration of IBRs in the future. 

Roger Clayton, chair of the RSS, said the plan is to modify PRR-151 based on the comments received, with the expectation that the revised rule will be presented to and approved by the EC at its next meeting in February.