NOTICE DATE: March 19, 2013

NOTICE TYPE: M-A031913-01NPRR

SHORT DESCRIPTION: Implementation details for NPRR496

INTENDED AUDIENCE: ERCOT Market Participants

DAY AFFECTED: April 2, 2013

LONG DESCRIPTION: On April 2, 2013, with the planned network operations model load, ERCOT will implement Nodal Protocol Revision Request (NPRR) 496, Revise West Hub Definition Due to Permanent Topology Change, which was approved by the ERCOT Board on March 19, 2013. NPRR496 revises the West 345 kV Hub to replace the Sweetwater Cogen (SWCOG) Hub Bus with Sweetwater East Switch (SWESW) Hub Bus.

ADDITIONAL INFORMATION: Pursuant to Protocol Section 21.6, Nodal Protocol Revision Implementation, ERCOT is required to provide notice as soon as practicable, but no later than ten days prior to implementation.

NPRR496 and associated documents can be found on the ERCOT website, under Market Rules, at http://www.ercot.com/mktrules/issues/nprr/476-500/496/index.

CONTACT: If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at [log in to unmask].

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