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Transmission Expansion

The addition or modification of facilities of the Transmission System.

Definition by NYISO

Source: 1 (p4, Version 4.2)

A transmission expansion is the addition or modification of facilities of the NYS Transmission System that may be proposed or initiated by an Eligible Customer, including a TO, under Section 3.7 of or Attachment P to the NYISO OATT.


Last modified: 2025-06-22

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  1. NYISO (2023). Manual 23: Transmission Expansion and Interconnection Manual. https://www.nyiso.com/documents/20142/2924447/tei_manual.pdf/94a26e65-fd68-98e1-535b-fc41a9536607