NYISO TPAS 06/25 Meeting Summary
NYISO has presented its proposed scenarios for the 2026 Reliability Needs Assessment and opened them for comment. There are ten Potential Scenarios, A through J, plus eight Other Scenarios that serve as stress tests. None of it is binding this cycle, and no reliability need will be declared from any scenario.
NYISO is running the exercise as a dry run for its proposed move to scenario-based reliability planning. Written feedback is due to NYISO by July 2, with the final scenario list expected in late July. Each Potential Scenario takes the base case and shifts one or two assumptions to sketch a plausible future.
The Other Scenarios push conditions to the edges to see where the analysis holds. Large loads run through much of the set. Some scenarios take data-center and large-load demand up toward roughly 4,100 MW by 2036, well above the 2,700 MW base case, while others strip new large loads out entirely to isolate how much of any future need, they actually drive.
Aging generation gets similar treatment, with up to about 3,000 MW at risk by 2036 set against a replacement queue that is mostly renewables, drawn from a cost-allocated pool of roughly 10,900 MW against the 6,300 MW base case. Two assumptions are new this cycle. One adds 1 GW of nuclear by 2036, reflecting new nuclear goals. The other introduces extreme temperature, anchoring a scenario that models a warmer regional peak near 35,300 MW with added generation derates and thinner imports when the heat is widespread, and it doubles as a first look at how NYISO may approach the coming NERC TPL-008 standard.
A separate scenario probes weaker reactive support from inverter-based resources at low output, a voltage support question as more of the fleet becomes Inverter-based.
Date Milestone:
- July 2 Stakeholder feedback on scenarios due
- Late July Final scenario list posted
- July–August Preliminary base-case results; scenario evaluation
- September Draft RNA report
- October–November Committee and Board review and final report published
Prepare for the Future of NYISO Reliability Planning
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