RENSSELAER, N.Y. — NYISO last week updated stakeholders on its draft Reliability Needs Assessment, which still shows an expected capacity shortfall by 2034, though it is slightly less than what was initially presented in July.

The ISO told the Transmission Planning Advisory Subcommittee on Sept. 3 that it had increased its assumption of special-case resource elections by about 200 MW. That resulted in a slightly lower loss-of-load expectation of 0.254 — still well above the required 0.1.

NYISO in July said it expected to be short by at least 1 GW, with an LOLE of 0.283, by 2034. (See Prelim NYISO Analysis: 1-GW Shortfall by 2034.)

The ISO also revised down New York City’s transmission security margin deficit, from 275 MW to 97 MW, by updating its load distribution model.

“We continue to see statewide resource deficiency by 2034,” said Ross Altman, senior reliability manager for NYISO.  “That is still driven by increasing demand, continued additions of large loads and unavailability of gas during winter peak conditions.”

In response to a stakeholder question, Altman said NYISO estimates the statewide resource adequacy need to be about 800 MW, but it “could be as high as 1,875 MW” for transmission security. “It’s very hard to put a number on it,” he said.

The TPAS and Electric System Planning Working Group will review the draft RNA later this month. The Operating and Management committees are expected to vote on it next month, with a Board of Directors review and vote in November.