Download Document 8854960

Stakeholder Comment and AESO Replies Matrix
Proposed New Section ISO Rules Part 300 System Reliability and Operations, Division 304 Routine Operations, Section 304.5, Provision for Operation of a Transmission Facility
within Ratings (“New Section 304.5”)
Date of Request for Comment:
Period of Consultation:
September 24, 2015
September 24, 2015
through
October 13, 2015
1. ISO Rules
Stakeholder Comments and/or Alternate Proposal
AESO Replies
a) New
AltaLink Management Ltd. (“AltaLink”)
1. Agree, however we do have comments on the associated
definitions.
1. The AESO acknowledges AltaLink’s agreement with New
Section 304.5.
The AESO is seeking comments from stakeholders with
regard to the following matters:
1. Do you agree or disagree with the proposed New
Section 304.5? If you disagree, please provide
comments.
2. Are there any subsections where the language does
not clearly articulate the requirement for either the
AESO or a market participant? If yes, please indicate
the subsections and suggest language that would
improve the clarity.
AESO Replies to Stakeholder Comments: March 3, 2016
TransAlta Corporation (“TransAlta”)
2. TransAlta is not opposed to the transition of TFO Terms
and Conditions to ISO rules, but TransAlta is concerned
that applying these ISO rules to all legal owners of
transmission facilities results in new compliance obligations
for some organizations. Radial transmission facilities are
sometimes owned by orgranizations other than the
regulated TFOs because a radial facility was constructed
and operated as part of a generating unit’s connection to
the system or as part of an industrial system. It appears
that the intent of this rule is to transition obligations that
exist for regulated TFOs into the ISO rules, but the
application of this proposed rule to all legal owners of
transmission facilities captures a number of additional
organizations that own unregulated radial transmission
facilities. The application of this proposed rule to radial
facilities does not create any benefit to the system.
Consider a radial transmission facility serving a generating
unit. Such a facility is usually designed to accommodate
the full output of the generating unit, and therefore cannot
violate section 2 of the proposed rule. This radial
transmission facility cannot be used to accommodate
power flow following a contingency elsewhere in the
2. The AESO disagrees with TransAlta that it is not possible for
the legal owner or operator of a radial transmission facility to
contravene New Section 304.5.
For example, where the thermal limit of a radial transmission
facility connecting a generating unit is derated, the derated
thermal limit of the radial transmission facility effectively
becomes its normal rating. In such cases, the normal rating
for the radial transmission facility may be less than the
planned output of the generating unit, such that the radial
transmission facility will not be able to operate within normal
ratings under pre-contingency conditions, in accordance
with subsection 2 of New Section 304.5.
A legal owner or operator of a radial transmission facility
may also contravene New Section 304.5 where a radial
transmission facility connecting a generating unit
experiences operating conditions such that the normal or
emergency voltage limits of the radial transmission facility
are exceeded. In such circumstances, the voltage at the
point of interconnection of the radial transmission facility
may impact the operating voltages of the Alberta
Page 1 of 2
system, and therefore cannot violate either sections 3 or 4
of the proposed rule. It is not possible for a radial facility to
violate any part the proposed rule, yet the rule would apply
to the legal owner of such a facility and create a regulatory
burden for that legal owner. TransAlta submits that the
proposed rule should not apply to radial transmission
facilities. The AESO could use similar language to that in
EOP-001-AB-2b and EOP-003-AB1-1 which do not apply to
“the operator of a transmission facility whose transmission
facility is a radial connection from a generating unit or an
aggregated generating facility”.
interconnected electric system (“AIES”). Where the normal
or emergency voltage limits are exceeded, the radial
transmission facility will not be able to operate within normal
ratings or emergency ratings, respectively, in accordance
with subsection 2 and 3 of New Section 304.5.
In both of the examples described above, the AESO and the
operator of the radial transmission facility may have to
coordinate actions, in accordance with subsection 4 of New
Section 304.5, to resolve the condition.
For example, in a post-contingency condition, the voltage at
the point of interconnection of the radial transmission facility
may decrease below an acceptable value and may affect
voltages further into the AIES. Post-contingency actions
may involve the AESO directing the operator of a radial
transmission facility to increase the reactive power output of
its on-site generator or decrease on-site load to restore
voltage to within the normal values.
Requiring the legal owners and operators of radial
transmission facilities to comply with New Section 304.5 will
support the AESO’s reliable operation of the AIES, as the
legal owners and operators of radial transmission facilities
will be required to operate their facilities within normal
ratings and emergency ratings under pre-contingency
conditions, and the actions for returning the loading of the
radial transmission facilities to, or within, their normal ratings
will be a coordinated effort between the operators of the
radial transmission facilities and the AESO.
AESO Replies to Stakeholder Comments: March 3, 2016
Page 2 of 2