Schedule 4:
Energy Imbalance Service
Energy Imbalance Service is provided when a difference occurs between the scheduled
and the actual delivery of energy to a load located within a Control Area over a single hour. The
Transmission Provider must offer this service when the transmission service is used to serve load
within its Control Area. The Transmission Customer must either purchase this service from the
Transmission Provider or make alternative comparable arrangements, which may include use of
non-generation resources capable of providing this service to satisfy its Energy Imbalance
Service obligation. To the extent the Control Area operator performs this service for the
Transmission Provider, charges to the Transmission Customer are to reflect only a pass-through
of the costs charged to the Transmission Provider by that Control Area operator. The
Transmission Provider may charge a Transmission Customer a penalty for either hourly
generator imbalances under Schedule 9 or hourly energy imbalances under Schedule 4 for the
same imbalance, but not both.
1.
Energy imbalances within a deviation band of ± 1.5 percent (with a minimum bandwidth
of ± 2 MW) of scheduled deliveries will be subject to the charges for Energy Imbalance
Service set forth below:
A.
Negative energy imbalances (deliveries to the Customer exceed schedule) will be
billed to the Transmission Customer at a rate equal to 100% of the Transmission
Provider’s Incremental Energy Cost for the hour in which the deviation occurred.
B.
Positive energy imbalances (schedule exceed deliveries to the Customer) will be
purchased by the Transmission Provider at a rate equal to 100% of the
Transmission Provider’s Decremental Energy Cost for the hour in which the
deviation occurred.
2.
Charges for energy imbalances outside the deviation band will be based on an aggregate
of the total imbalance for all customers purchasing any energy imbalance or generator
imbalance from the NV Energy, Inc. Operating Companies. This aggregate will be
calculated, by Zone, by summing the total imbalances, both positive and negative, for all
customers including any amount within the deviation band.
A.
If the aggregate imbalance is less than or equal to ± four (4) MW for Zone A or ±
twenty (20) MW for Zone B, energy imbalances outside the deviation band will
be subject to the charges for Energy Imbalance Service set forth below:
(1)
Negative energy imbalances (deliveries to the Customer exceed schedule)
will be billed to the Transmission Customer at a rate equal to 100% of
Transmission Provider’s Incremental Energy Cost for the hour in which
the deviation occurred.
(2)
Positive energy imbalances (schedule exceeds deliveries to the Customer)
will be purchased by the Transmission Provider at a rate equal to 100% of
Transmission Provider’s Decremental Energy Cost for the hour in which
the deviation occurred.
B.
If the aggregate imbalance is greater than ± four (4) MW for Zone A, or ± twenty
(20) MW for Zone B, energy imbalances outside the deviation band and in the
same direction as the aggregate imbalance will be subject to the charges for
Energy Imbalance Service set forth below:
(1)
Negative energy imbalances (deliveries to the Customer exceed schedule)
outside the deviation band and less than or equal to 5 percent of scheduled
deliveries (with a minimum bandwidth of 5 MW) will be billed to the
Transmission Customer at a rate equal to 110% of Transmission Provider’s
Incremental Energy Cost for the hour in which the deviation occurred.
Remaining negative energy imbalance will be billed to the Transmission
Customer at a rate equal to 120% of the Transmission Provider’s
Incremental Energy Cost for the hour in which the deviation occurred.
(2)
Positive energy imbalances (schedule exceeds deliveries to the Customer)
outside the deviation band and less than or equal to 5 percent of scheduled
deliveries (with a minimum bandwidth of 5 MW) will be purchased by the
Transmission Provider at a rate equal to 90% of Transmission Provider’s
Decremental Energy Cost for the hour in which the deviation occurred.
Remaining positive energy imbalance will be purchased by the
Transmission Provider at a rate equal to 80% of the Transmission Provider’s
Decremental Energy Cost for the hour in which the deviation occurred.
C.
If the aggregate imbalance is greater than ± four (4) MW for Zone A or ± twenty
(20) MW for Zone B, energy imbalances outside the deviation band and in the
opposite direction from the aggregate imbalance will be charged as being within
the deviation band.
3.
Deviations from Schedule:
A.
The Transmission Provider may request during an hour that a Transmission
Customer deviate from its schedule in order to alleviate a system imbalance or
reliability issue. Such a deviation shall be deemed an “instructed deviation.” In
the case that a Transmission Customer agrees to implement an instructed
deviation and such instructed deviation otherwise would result in that
Transmission Customer incurring a penalty under this Schedule for that hour, the
Transmission Customer who complied with the instructed deviation will be
charged for that hour as being within the deviation band. A notification from the
Transmission Provider to a Transmission Customer directing that the
Transmission Customer balance its loads and resources will not be considered an
instructed deviation.
B.
In the event that (i) the Transmission Customer has deviated from its schedule and
has a positive imbalance that is in excess of the deviation band and (ii) corrective
action has not been taken by the Transmission Customer within one (1) hour of
being notified by the Transmission Provider to eliminate such imbalance, that
Transmission Customer shall be deemed to have intentionally delivered energy
imbalance. No energy imbalance payment shall be owed for positive deviation
intentionally delivered energy imbalances delivered by the Transmission
Customer to the Transmission Provider. Upon being notified by the Transmission
Provider to reduce positive imbalance, the Transmission Customer may request
that the Transmission Provider clarify whether it is proposing an instructed
deviation or is requiring the Transmission Customer to reduce its positive
deviation in order to avoid an intentionally delivered energy imbalance.
For purposes of this Schedule 4, “Transmission Provider’s Incremental Energy Cost” shall be
defined as the greater of:
A.
The highest hourly system incremental generation cost. The incremental generation cost
for each Zone shall be calculated based on the daily incremental fuel cost and the
applicable unit’s incremental heat rate curve plus the applicable unit’s O&M cost.
The O&M cost shall be equal to the average O&M cost per kWh for the applicable unit
derived from the most recent FERC Form 1 filing; or
B.
The hourly “Market Price Proxy” (“MPP”). The MPP will be calculated from the
appropriate daily Dow Jones Firm Electricity Price Index.
Zone A:
The on-peak and off-peak dailyhourly California-Oregon Border (COB)
Index prices shaped by the Mid-Columbia (Mid-C) hourly index report plus
a basis difference shall be used. The basis is equal to the point-to-point
transmission rates for PacifiCorp and the Bonneville Power Administration
under their respective OATT and shall be updated as necessary. The current
basis difference is $8.569.66/MWH and 6.4690% for losses.
Zone B:
The on-peak and off-peak daily Mead/Marketplace Index prices shaped by
the Palo Verde hourly index report shall be used for on-peak and off-peak
hours.
“Transmission Provider’s Decremental Energy Cost” shall be calculated hourly and is defined as
the lesser of:
A.
The highest hourly system incremental generation cost. The incremental generation cost
for each Zone shall be calculated based on the daily incremental fuel cost and the
applicable unit’s incremental heat rate curve; or
B.
The hourly MPP. The MPP will be calculated from the appropriate daily Dow Jones Firm
Electricity Price Index.
Zone A:
The on-peak and off-peak daily hourly California-Oregon Border (COB)
Index prices shaped by the Mid-Columbia (Mid-C) hourly index report
minus a basis difference shall be used. The basis is equal to the point-topoint transmission rates for PacifiCorp and the Bonneville Power
Comment [PE1]: Rates updated per BPA and
Pacificorp tariffs.
Administration under their respective OATT and shall be updated as
necessary. The current basis difference is $8.569.66/MWH and 6.4690% for
losses.
Zone B:
The on-peak and off-peak daily Mead/Marketplace Index prices shaped by
the Palo Verde hourly index report shall be used for on-peak and off-peak
hours.
Credit to Transmission Customers for Imbalance Penalty Charges
For any hour for which the Transmission Provider collects any charge for a negative
deviation where such charge is greater than the Transmission Provider’s Incremental Energy
Cost, the Transmission Provider shall credit to Qualified Transmission Customers for such hour
the amount by which such charge exceeded the Transmission Provider’s Incremental Energy
Cost. For each such hour, the amount of such credit shall be allocated among Qualified
Transmission Customers for such hour in proportion to their respective Qualified Transmission
Loads for such hour. The calculation will be done monthly, for all hours of the month, on a onemonth lagging basis. The calculations shall be made separately for Zone A and for Zone B.
For purposes of this Schedule 4, the following definitions shall apply:
(a)
(b)
"Qualified Transmission Customer" means each of the following::
(i)
Long-Term Firm Point-to-Point Transmission Service Customer;
(ii)
Network Customer; or
(iii)
Transmission Provider on behalf of its Native Load Customers.
"Qualified Transmission Load" for any hour means the following with respect to
each Qualified Transmission Customer:
(i)
For each Long-Term Firm Point-to-Point Transmission Service Customer,
its Reserved Capacity applicable to such hour;
(ii)
For each Network Customer, its load for such hour; or
(iii)
For the Transmission Provider on behalf of its Native Load Customers, the
hourly load in such hour.