NOTICE DATE: December 9,
2010
NOTICE TYPE: M-A120910-01
NPRR
SHORT DESCRIPTION: Implementation
Details of NPRR277
INTENDED AUDIENCE: ERCOT
Market Participants
DAY AFFECTED: December 1,
2010
LONG DESCRIPTION: Nodal Protocol
Revision Request (NPRR) 277, as approved by the ERCOT Board of Directors,
became effective for Operating Day December 1, 2010. NPRR277 added a new parameter (REGP) to the SCED up ramp rate (SURAMP)
calculation.
The system was originally coded as
SURAMP = Ramp Rate – (Regulation/X), where X = 5. According to the system
requirements, X must be an integer. The new formula is:
SURAMP = Ramp Rate –
(Regulation * REGP/5).
In order to accomplish the change
without adding a new parameter to the existing code, the original X is replaced
with 5/REGP and the equation is re-written as:
SURAMP = Ramp Rate –
(Regulation / (5/REGP)).
REGP is the percentage of
regulation service for which ramp rate will be reserved in real-time. The value
is to be between zero and one with an initial setting of 0.75 as agreed upon
through the stakeholder process. Due to the ERCOT System requiring the 5/REGP
parameter to be an integer, ERCOT will be required to round the calculation of
5/0.75 from 6.66 to 7 which results in the REGP value effectively changing to
0.714 ( 5/0.714 = 7).
ERCOT changed the REGP value to
0.714 at 23:59 CST November 30, 2010, to be effective starting with Operating
Day December 1, 2010.
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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dh