Stakeholder Comment and Replies Matrix AESO AUTHORITATIVE DOCUMENT PROCESS

Stakeholder Comment and Replies Matrix
AESO AUTHORITATIVE DOCUMENT PROCESS
Proposed “Allowable Dispatch Variance” Amended ISO Rule Definition (“Allowable Dispatch Variance Definition Amendment”)
Date of Request for Comment [yyyy/mm/dd]:
Period of Consultation [yyyy/mm/dd]:
2014-04-29
2014-04-29
Definitions – Amended
Existing
“allowable dispatch variance” means, for
each generating source asset as measured
from the dispatch quantity:
(i) plus or minus five (5) MW for a generating
source asset with a maximum capability of
two hundred (200) MW or less, or
(ii) plus or minus ten (10) MW for a generating
source asset with a maximum capability of
greater than two hundred (200) MW.
through
2014-05-28
Proposed
Rationale
“allowable dispatch variance”
means:
Wind aggregated generating facilities
cannot control their output when
wind speed is decreasing, but they
can control their output when wind
speed is increasing and if they are
equipped with new control
technology. Accordingly, the AESO
proposes to change the definition of
“allowable dispatch variance” to also
apply to wind aggregated generating
facilities.
(i) for each generating source
asset, other than a wind
aggregated generating facility,
as measured from the dispatch
quantity:
(a) plus or minus five (5)
MW for a generating
source asset with a
maximum capability of
two hundred (200) MW or
less; or
(b) plus or minus ten (10)
MW for a generating
source asset with a
maximum capability of
greater than two hundred
(200) MW;
(ii) for each wind aggregated
Final Draft for Internal Approval to File: 2014-08-19
The dispatch quantity of a wind
aggregated generating facility is
based on its in-merit energy offer. If
its potential real power capability in
real-time is less than the dispatch
quantity, the lower boundary of the
allowable dispatch variance is
measured from that potential real
power capability. The wind
aggregated generating facility will
remain in compliance as long as its
output does not exceed the dispatch
Stakeholder Comments
and/or Alternate Proposal
Capital Power
1. Capital Power appreciates
the AESO’s commitment to
consult with stakeholders
on changes to the ISO
Rules Framework. After
reviewing the draft definition
of ADV, Capital Power
understands the proposed
amendments to apply only
to non-exempt wind
aggregated generating
facilities (as described in
ISO Rules Section 304.3
and 502.1) that are
dispatched on non-zero
dollar offer blocks. As a
result, Capital Power does
not oppose the changes.
ENMAX
2. Conceptually, ENMAX
agrees that there should be
allowable dispatch
AESO Reply
1. Acknowledged.
2. To remain in compliance with
a dispatch, each wind
aggregated generating facility
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generating facility with a
maximum capability of two
hundred (200) MW or less:
(a) five (5) MW greater
than the dispatch quantity
and five (5) MW less than
the potential real power
capability, if the potential
real power capability is
less than the dispatch
quantity; or
(b) plus or minus five (5)
MW from the dispatch
quantity, if the potential
real power capability is
greater than or equal to
the dispatch quantity; and
(iii) for each wind aggregated
generating facility with a
maximum capability of greater
than two hundred (200) MW:
(a) ten (10) MW greater
than the dispatch quantity
and ten (10) MW less than
the potential real power
capability, if the potential
real power capability is
less than the dispatch
quantity; or
(b) plus or minus ten (10)
MW from the dispatch
quantity, if the potential
real power capability is
greater than or equal to
the dispatch quantity.
Final Draft for Internal Approval to File: 2014-08-19
quantity by more than the allowable
dispatch variance.
If the potential real power capability
of a wind aggregated generating
facility is greater than or equal to the
dispatch quantity, the allowable
dispatch variance is measured from
the dispatch quantity as it is for a
generating source asset that is not a
wind aggregated generating facility.
variances associated with
wind aggregated generating
facilities, at least when the
wind is increasing. For the
following reasons, however,
ENMAX is less clear on the
usefulness of a lower limit
on wind production.
Additional work on some
definitions may help.
3. There appears to be no
definition of the term
“potential real
powercapability.” It is not
clear to ENMAX whether it
is: (i) the maximum output
of a wind aggregated
generating facility under
maximum wind conditions,
which output could be less
than the facility’s maximum
capability due to one or
more turbines being off line,
and as (presumably) to be
reported in accordance with
Rule 306.5; or (ii) the
maximum output likely
given current (real time)
forecasts, as ENMAX
understands is to be
reported in accordance with
sections 25(4) and (5) of
Rule 502.1. It would be
helpful to have an explicit
definition. If “potential real
power capability” is
intended to mean “available
capability,” the latter term
should be used and
perhaps re-defined with
wind generators in mind.
must produce its potential real
power capability (within 5 MW
or 10 MW depending on its
size) if it is in-merit, even if its
potential is falling in real time.
A wind aggregated generating
facility cannot physically
withhold in-merit energy.
3. “Potential real power
capability” is defined in
Appendix 2 of section 502.8 of
the ISO rules, SCADA
Technical and Operating
Requirements, as follows:
“Potential real power capability,
being the real power that would
have been produced at the
point of connection without
wind aggregated generating
facilities curtailment and based
on real time meteorological
conditions at each available
wind turbine generator”.
Available capability (AC) is not
related to wind speed on site.
AC as it relates to a generating
source asset is the maximum
MW that the source asset is
physically capable of providing.
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4. It is not clear to ENMAX
4. The energy dispatch will be
how the potential real power
based on the offer. For a wind
capability of a wind
farm offering at zero (0)
aggregated generating
dollars, the energy dispatch
facility could be less than
will be the maximum
the dispatch quantity.
capability (MC) assuming
ENMAX assumes that this
there is no derating. The
situation would arise when
system controller will not
a wind facility has submitted
constantly re-dispatch the
an offer volume (at zero
wind farm as its potential real
dollars or otherwise) that it
power capability fluctuates as
is not able to achieve.
long as it remains in-merit.
Presumably, however, the
System Controller would
immediately re-dispatch the
wind generator to the level it
is capable of achieving.
5. ENMAX believes that
additional clarity on this rule
will be particularly important
in situations in which both
wind and non-wind
generators face
curtailments due to
limitations on available
transmission capability
under the to-be-developed
TCM Rule(s).
TransCanada
6. As per comments made in
the matrix for Section 304.3,
“potential real power
capability” is unclear.
Without clarity on this TCE
cannot assess this
proposed definition change.
Suncor Energy Products Inc.
7. The AESO is proposing an
Allowable Dispatch
Final Draft for Internal Approval to File: 2014-08-19
5. If the transmission constraint
management (TCM) directive
is lower than the energy
dispatch, the wind generator
will have to limit itself to the
TCM directive, as per section
302.1 of the ISO rules.
6. Please see AESO Reply #3.
7. A dispatch pilot conducted in
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Variance (ADV) of 5 MW
above or below the dispatch
quantity for wind facilities <
200 MW if the potential real
power is equal or greater to
the dispatch quantity.
Suncor believes that the
ADV is too low for wind
facilities of this size.
Suncor’s Wintering Hills is
an 88 MW facility consisting
of 55 - 1.6 MW turbines.
Under the AESO’s
proposed ADV of 5 MW, the
variance band is equivalent
to only 3.1 turbines in
capacity. The AESO’s
proposed ADV does not
take into consideration the
size of the turbines at
individual wind farms. With
turbines available in the 3 to
5 MW range, wind
generators risk ADV noncompliance due to
unscheduled turbine down
time. The ADV should be a
percentage of the wind
facility’s total capacity. In
the case of Wintering Hills
an ADV of 10% would be
equivalent to 8.8 MW and
represents a more
reasonable operational limit.
Final Draft for Internal Approval to File: 2014-08-19
2012 by the AESO using 2 X
66 MW wind farms indicated
that staying within the
Allowable Dispatch Variance
(ADV) as production goes
down was more challenging
for the market participant than
staying within the ADV as
production goes up. This
finding from the dispatch pilot
is addressed in the proposed
definition.
The wind farm described in
Suncor’s example will remain
in compliance, because, if
turbines go down, then the
wind farm’s potential real
power capability will go down.
The AESO is committed to
monitoring the effectiveness
of the rule and will make
improvements as necessary.
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