HomeMy WebLinkAbout20240329PAC to Staff 39-47.pdf _ ROCKY MOUNTAIN
POWER
A DIVISION OF PACIFICORP
1407 W North Temple, Suite 330
Salt Lake City, Utah 84116
March 29, 2024
Monica Barrios-Sanchez
Commission Secretary
Idaho Public Utilities Commission
11331 W. Chinden Blvd.
Bldg. 8, Ste. 201-A
Boise, ID 83714
monica.barriossanchez(ir,puc.Idaho.gov
Secre1M(-,1)uc.idaho.9ov (C)
RE: ID PAC-E-23-17
IPUC Set 4 (39-47)
Please find enclosed Rocky Mountain Power's Responses to IPUC 41h Set Data Requests 39-47.
Also provided are Attachments IPUC 39-1 and 40. Provided via BOX are Confidential
Attachments IPUC 39-2, 44, and 47. Confidential information is provided subject to protection
under IDAPA 31.01.01.067 and 31.01.01.233, the Idaho Public Utilities Commission's Rules of
Procedure No. 67—Information Exempt from Public Review, and further subject to the
protective agreement executed in this proceeding.
If you have any questions, please feel free to call me at(801)220-2313.
Sincerely,
/s/
Mark Alder
Manager, Regulation
Enclosures
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 39
IPUC Data Request 39
Although the Company discusses the advantages and disadvantages of seasonal
and time-of-use pricing for the Export Credit Rate (ECR); the Company does not
provide any numerical examples for the energy component of the ECR in the On-
Site Generation Study (Study). Please provide hypothetical seasonal pricing for
the energy component using the Schedule 1 seasons (June to October and
November to May). Please include the worksheets (with formulas enabled) used
to determine the pricing.
Response to IPUC Data Request 39
Please refer to Attachment IPUC 39-1 which provides the summary of seasonal
energy pricing and Confidential Attachment IPUC 39-2 which provides the
calculations supporting the summary of seasonal energy pricing. Note: the
information provided has not yet been adjusted for line losses, which would
increase both summer and winter values by the same percentage. Compensation
under the summer and winter rates would be identical to the annual rates
previously provided so long as the split of summer and winter volumes aligned
with the sample export profile.
Energy values are generally higher in the summer.Note: while the June-October
summer season is only five months long, as a result of longer days and the higher
angle of the sun in the sky, slightly over half of the annual exports occur in that
timeframe in the export profile.
Confidential information is provided subject to protection under IDAPA
31.01.01.067 and 31.01.01.233, the Idaho Public Utilities Commission's Rules of
Procedure No. 67—Information Exempt from Public Review, and further subject
to the non-disclosure agreement(NDA) executed in this proceeding.
Recordholder: Dan MacNeil
Sponsor: Dan MacNeil
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 40
IPUC Data Request 40
In its responses to Production Requests No. 5 and 8, the Company showed that the
Loss of Load Probability (LOLP)distribution depends significantly on the test
year-which in turn affects the ECR avoided capacity value. Please address the
following issues:
(a) Please provide a list of the test years and LOLP distributions that the
Company calculated in the 2021 Integrated Resource Plan (IRP) and in the
2023 IRP;
(b) Please provide the 12-month by 24-hour(12-24) distributions for the 2026 test
year from both IRPs. If the 2023 IRP did not calculate a 2026 test year
distribution, provide the next closest test year distribution; and
(c) For these two distributions, please provide the resulting avoided capacity
value (using the proxy Utah export data).
Response to IPUC Data Request 40
The Company assumes that the reference to "No. 5 and 8" are intended to be
references to the Company's responses to IPUC Data Request 5 and IPUC Data
Request 8. Based on the foregoing assumption, the Company responds as follows:
(a) The Company prepared a 2030 loss of load probability (LOLP) distribution
that was filed with PacifiCorp's 2021 Integrated Resource Plan (IRP)using a
portfolio that was close to the 2021 IRP preferred portfolio, and later
calculated LOLP distributions using the 2021 IRP preferred portfolio for
2024, 2028, 2032, 2036 and 2040. The Company has not prepared LOLP
distributions for any years based on PacifiCorp's 2023 IRP.
(b) Please refer to Attachment IPUC 40 which provides the LOLP distribution
and capacity contribution for the export profile based on the 2026 test year,
calculated as the average of the available values for 2024 and 2028 using the
2021 IRP. The Company does not have an LOLP distribution for the 2023
IRP. Please refer to the Company's response to subpart(a) above.
(c) Please refer to the Company's response to subpart(b) above.
Recordholder: Dan MacNeil
Sponsor: Dan MacNeil
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 41
IPUC Data Request 41
The Company's calculation of the export capacity factor(Appendix 4.2, Summary
Tab, column C, rows 4 to 23) yields an identical value of 9% for each of the 20
years-which could change over time. Staff traced the source of this value and
found that the Company derived each year's capacity factor from only one year
12-24 Hourly Capacity Factor distribution-the hourly distribution of the Utah
proxy data. In effect, the capacity factor for each of the 20 future years is equal to
the capacity factor of the current year's exports. This highlights one of the
problems with providing a 20-year forecast of the ECR. Please provide the
following information:
(a) Please explain why the Company forecasts the ECR value for each of the 20
years when various ECR component values are based on recent historical
data; and
(b) Please discuss the pros and cons of updating the various ECR component
values and discuss possible update frequencies for each component.
Response to IPUC Data Request 41
Referencing the Company's calculation of the export capacity factor(Appendix
4.2), the Company responds as follows:
(a) The hourly export profile is largely a result of solar insolation, with a limited
effect related to customer load, therefore, the Company does not anticipate
dramatic changes over time. Customer load does have a relationship with
prices—high loads would result in low exports and could be more likely to
coincide with high energy prices, while low loads would result in high exports
and could be more likely to coincide with low energy prices. The available
historical export profiles and energy imbalance market(EIM) data indicate
that exports tended to occur when prices were slightly below average in 2021,
while they occurred when prices were slightly above average in 2022. Within
each year, there are months where the value of exports were both above and
below average. Please refer to the Company's response to IPUC Data Request
39, specifically Confidential Attachment IPUC 39-2, tab "CZ6B EIM
Summary"which provides details. This indicates that prices are likely being
more heavily impacted by other factors. The 20-year forecast similarly is
primarily reflective of the Company's system costs, and not particularly
related to the export profile.
(b) Regarding updating export credit rate components:
- Energy: This is the vast majority of the export credit rate (ECR). A rate
based on historical EIM prices is inherently accurate and transparent, since
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 41
those prices are public, making it easy to calculate and review. Annual
updates are possible, though given that the rate effective period will
always lag the historical data, less frequent rate adjustments may be
sufficient and help smooth out volatility. For a forecasted rate, the most
likely source is PacifiCorp's Integrated Resource Plan (IRP), which is
published every two years. The IRP does not reflect near-term changes, as
assumptions are locked down well before the publication date, and IRP
acknowledgment, where applicable, occurs even later, however results
from the IRP could be used to set ECRs on a prospective basis.
- Capacity (Generation, Transmission, Distribution): These costs are
forecasted in each IRP, and generally do not change significantly from
IRP to IRP, however, the capacity contribution and deficiency period may
change and impact pricing. For example, based on PacifiCorp's 2023 IRP,
generation capacity payments would occur in 2024, rather than starting in
2026 based on PacifiCorp's 2021 IRP. To the extent a clear methodology
is developed to use specified inputs from the IRP or actual operations,
updates to capacity could occur annually, or with each IRP. However, it
may be simpler to leave some or all of the capacity components in place
for a length of time, such as between rate cases, and address them
holistically with other retail rate components.
- Line Losses: Line losses are primarily a function of energy value, with a
small component associated with capacity value. Updating the total line
loss value whenever energy value changes is appropriate. The line loss
percentages are usually addressed in general rate cases, therefore, leaving
them at the levels identified in the most recent GRC is recommended.
Given the limited size of the change, any update to line loss percentages at
the completion of a GRC would likely be incorporated at the next
regularly scheduled update.
- Integration: These costs are forecasted in each IRP, and are a relatively
small portion of the total, so any update could be incorporated at the next
regularly scheduled update.
- Risk: These costs are forecasted in each IRP, and are a relatively small
portion of the total, so any update could be incorporated at the next
regularly scheduled update.
Recordholder: Dan MacNeil
Sponsor: Dan MacNeil
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 42
IPUC Data Request 42
Section 4.5 discussed the value of avoided risk. Please answer the following:
(a) Please explain in more detail the underlying concepts of this value;
(b) Please explain the underlying data that the Company used to determine the
value;
(c) Please explain the calculational steps the Company used in Appendix 4.2 to
determine the value; and
(d) Please explain if the value of avoided risk would be embedded in an EIM-
based avoided energy cost that was regularly updated.
Response to IPUC Data Request 42
(a) The forecast of energy values presented in the Company's Application in this
proceeding are based on a deterministic Integrated Resource Plan (IRP) study
with normal conditions: expected market prices, median load and hydro and
average thermal outages. In reality, each of these variables is likely to be
higher or lower than the normal level. Some combinations of conditions, such
as high load and high thermal outages are likely to result in very high costs,
such as administrative pricing during resource shortfalls, while the opposite,
low load and low thermal outages, results in relatively modest benefits in
avoided fuel. As a result, the average value of the range of outcomes may be
higher than the single normalized value. The incremental cost in excess of the
normalized value is characterized as a risk adjustment.
(b) Within the IRP, in addition to deterministic studies, the Company performs
stochastic analysis with varying combinations of market prices, load, hydro,
and thermal outages. Because many iterations are performed, to assess
different potential combinations, the granularity of the studies was reduced
and the medium-term (MT) PLEXOS model was used, instead of running
every hour of every year, as in the short-term deterministic analysis. Please
refer to the Company's response to IPUC Data Request 39, specifically
Confidential Attachment IPUC 39-2. The marginal energy value of each
energy efficiency (EE) resource is reported by year for each of the iterations,
as shown in column V on tab "Risk". Idaho EE options were used as a proxy
for the export profile. This value is reported by PLEXOS but is equivalent to
the energy value used for the export profile, which also reflects a defined
hourly energy profile multiplied by the locational marginal price (LMP)
reported by PLEXOS. Because the MT model is not as granular as the hourly
short-term (ST) model, the two values are not directly comparable, however, it
is reasonable to assume that the variance in the MT result among different
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 42
combinations of conditions is comparable to what would be identified in the
ST model, had it been run under all of those conditions, and that the measured
variance for EE would be similar to the variance for the export profile.
(c) As described in the Company's response to subpart(b) above, the PLEXOS
model reports the energy value of each resource. The values for Idaho EE
resource were reported by iteration from the MT model results in the 2021
IRP. The risk adjustment is converted to a percentage by dividing the standard
deviation by the mean value for each EE resource in each year. The risk
percentage specific to each year is then applied to the hourly energy value of
the export profile.
(d) Energy imbalance market (EIM)pricing would reflect actual market prices,
loads, hydro and thermal availability, therefore, it would reflect the avoided
cost from the specific combination of conditions that actually occurred. As a
result, the risk adjustment reflected in the Company's Application in this
proceeding would not be necessary.
Recordholder: Dan MacNeil
Sponsor: Dan MacNeil
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 43
IPUC Data Request 43
Appendix 8.2 provides the wind and solar integration costs approved in Order No.
34966 (Case No. PAC-E-20-14). However, the Company used the solar
integration costs from the 2021 IRP Appendix F-Flexible Reserve Study
(Appendix 8.1)to calculate the ECR. Please reconcile the two sources and clarify
the Company's intent for including solar integration costs in an ECR.
Response to IPUC Data Request 43
The Company would recommend, whenever the export credit rate (ECR) is
updated, it would include either:
(a) Integration costs from the most recently published Integrated Resource Plan
(IRP). This would incorporate the most recent integration results faster. This
may be appropriate if the ECR updates are infrequent and subject to extensive
review.
(b) Integration costs currently approved by the Idaho Public Utilities Commission
(IPUC) for use with qualifying facility (QF) pricing. This would incorporate
the integration results after an opportunity for more thorough review. This
may be appropriate if the ECR updates are frequent and have an objective list
of required update components, with less extensive review.
(c) The type of update could also determine the source, with a limited set of well-
defined annual updates relying upon option (b) above, while a more
comprehensive update in a general rate case (GRC) or stand-alone export
credit proceeding might rely upon option (a) above.
Given the size of the integration cost, relative to the ECR, the Company
recommends that the integration costs reflect readily available information and
not require significant review as part of the export credit update. Therefore the
Company would recommend that the IPUC specify which specific integration
costs should be reflected in each update. Note: the Company does not have a
strong preference among the options described above.
Note also that the Company currently has an open proceeding to update
integration costs (Case No. PAC-E-23-24)which is based upon results in the 2023
IRP. If the updated integration costs are approved in that proceeding, they would
be the same as in the most recently published IRP.
Recordholder: Dan MacNeil
Sponsor: Dan MacNeil
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 44
IPUC Data Request 44
With its Study Supplement, the Company submitted an updated Appendix 4.2
(Supplemental Appendix 4.2) in response to Staffs concerns over the prevalence
of confidential information. Please answer the following and, wherever possible,
provide public information separately from confidential information.
(a) Please provide a list of inputs, calculations, and other information present in
confidential Appendix 4.2 that were excluded from Supplemental Appendix
4.2;
(b) Please provide work papers supporting the calculations for each export credit
cost component (Component) excluded. If not already provided, please
include any other workpapers referenced by the calculations contained in
these work papers; and
(c) For each Component, input data set, or calculation excluded, please explain
how the Component is considered confidential under Idaho Code § 7 4-107.
Response to IPUC Data Request 44
Please refer to Confidential Attachment IPUC 39 -2 for a complete workpaper
supporting the calculations in Appendix 4.2 and Appendix 4.3. This attachment
includes one additional tab "Seasonal" with calculations specific to data request
IPUC 39 but otherwise supports Appendices 4.2 and 4.3 as filed.
(a) The Company treats the following as confidential:
- Hourly energy and operating reserve prices, reported by the PLEXOS
model.
- The Company's hourly Idaho load forecast.
- Risk-related calculations specific to energy efficiency (EE)programs,
including energy value by stochastic iteration and associated statistics.
- Hourly loss of load probability (LOLP)details could be treated as
confidential, however, given the vintage of the available results based on
PacifiCorp's 2021 Integrated Resource Plan(IRP), the Company did not
opt for confidential treatment in this instance.
- Details on the calculation of transmission and distribution capacity credits,
though the resulting forecasted values are publicly available in Table 7.10
on page 211 of Volume I in PacifiCorp's 2021 IRP.
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 44
Note: the Company is not treating the export credit profile (based on historical
exports) as confidential, nor energy imbalance market(EIM)prices are
publicly available.
(b) Please refer to the Company's response to IPUC Data Request 39, specifically
Confidential Attachment IPUC 39-2 as describe above. For additional details
on transmission and distribution capacity credits, please refer to Confidential
Attachment IPUC 44.
(c) The Company's price and load forecasts are commercially sensitive, as they
indicate the Company's price sensitivity, willingness to transact, and resource
needs, which if known by other market participants could result in less
favorable pricing for sales and purchases. Risk-related calculations similarly
provide an indication of the Company's price sensitivity.
Confidential information is provided subject to protection under IDAPA
31.01.01.067 and 31.01.01.233, the Idaho Public Utilities Commission's Rules of
Procedure No. 67—Information Exempt from Public Review, and further subject
to the non-disclosure agreement (NDA) executed in this proceeding.
Recordholder: Dan MacNeil
Sponsor: Dan MacNeil
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 45
IPUC Data Request 45
With its Study Supplement, the Company submitted an updated Appendix 4.3
(Supplemental Appendix 4.3) in response to Staffs concerns over the prevalence
of confidential information. Please answer the following and wherever possible,
provide public information separately from confidential information.
(a) Please provide a list of inputs, component, calculations, and other information
present in confidential Appendix 4.3 that were excluded from Supplemental
Appendix 4.3;
(b) Please provide work papers supporting the calculations for each Component
excluded. If not already provided, please include any other work papers
referenced by the calculations contained in these work papers; and
(c) For each Component, input data set, or calculation excluded, please explain
how the Component is considered confidential under Idaho Code § 7 4-107.
Response to IPUC Data Request 45
Please refer to the Company's response to IPUC Data Request 44.
Recordholder: Dan MacNeil
Sponsor: Dan MacNeil
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 46
IPUC Data Request 46
In response to Production Request No. 15, the Company provided the worksheet
"Resource Options 18609 P02 MM CET A CONF" referenced by the formulas in
confidential Appendix 4.2. Please answer the following:
(a) Please define the type of resource used to value the avoided cost of capacity;
(b) Please explain how the Company selected this resource;
(c) Please explain what other resources the Company considered and why they
were not used to value the avoided cost of capacity; and
(d) Please explain if this is the same resource used to value the avoided cost of
capacity for the Company's DSM programs.
Response to IPUC Data Request 46
The Company assumes that the reference to "No. 15"is intended to be a reference
to the Company's response to IPUC Data Request 15. Based on the foregoing
assumption, the Company responds as follows:
Please refer to the Company's response to IPUC Data Request 39, specifically
Confidential Attachment IPUC 39-2, tab"Gen Capacity"which provides
additional details supporting the calculation of the referenced generation capacity
costs.
(a) The referenced generation capacity resource is a non-emitting peaker,
assumed to be located in the Willamette Valley bubble, located in Oregon.
(b) Peaking resources are expected to operate at a relatively low capacity factor
(CF), and thus would generate relatively low energy benefits. In contrast,
resources with high Us would provide energy benefits to customers
throughout the year which would help defray their costs and would reduce the
revenue requirement impact when they go in service. PacifiCorp's 2021
Integrated Resource Plan (IRP) assumed that the economic life of natural gas
resources was at risk of being reduced for environmental compliance, and that
the annualized cost would exceed that of a non-emitting peaking resource as a
result. There was limited variation in build costs for non-emitting peaking
resources by location in PacifiCorp's 2021 IRP. The Willamette Valley,
Oregon resource has assumed costs that were slightly higher than the other
locations (an increase of less than 10 percent), but this is well within the
potential range of cost variation for this resource type, which is not in
operation today. The Company's calculation is based on the net cost of
capacity, i.e. the fixed costs of the resource less the net benefits of the energy
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 46
it produces, after accounting for variable costs and fuel. The referenced
peaking resource was not expected to operate, so it creates no net benefits.
After accounting for capacity contribution impacts, other resource types, like
wind, solar, or battery storage, are expected to have a net cost of capacity that
is higher than for the peaking resource. The net cost for those resources may
also be volatile over time, as their energy benefits and capacity contribution
will vary with the mix of resources in the preferred portfolio.
(c) Please refer to the Company's response to subpart(b) above.
(d) The resource referenced in the Company's response to subpart (a) above is the
same resource used to value generation capacity for avoided costs of the
Company's demand-side management (DSM) programs. However, in 2024,
the Company will begin to use values sourced from PacifiCorp's 2023 1".
Recordholder: Dan MacNeil/Peter Schaffer
Sponsor: Dan MacNeil/Peter Schaffer
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 47
IPUC Data Request 47
Study Scope item No. 15 directed the Company to quantify the potential value of grid
stability, among other items. The Company's Study Supplement, states that on-site
generation paired with batteries such as the Company's Wattsmart Batteries pilot
program can provide this benefit. Please answer the following questions:
(a) Please explain how the grid stability benefit of on-site generation paired with
storage is captured in the current design of the Wattsmart Battery pilot program;
(b) Please provide the benefit calculation workpapers for the Wattsmart Battery Pilot
program in excel format with equations intact and enabled. Please specify where
the grid stability benefit is captured in the calculation and include any other work
papers referenced in these calculations;
(c) Please describe in detail any differences in the source of avoided cost value
streams (e.g., energy, capacity, transmission, distribution, etc.)between the
Wattsmart Batteries program and those used to value the export credit costs from
table 4.1 of the Study;
(d) Please explain if the Wattsmart Batteries Pilot program has realized these benefits.
If so, please provide supporting data. If not, why not?
(e) Please explain why it may or may not be appropriate to include a grid stability
credit/benefit in a potential export credit rate for systems with paired battery
storage; and
(f) Please explain why the Company did not quantify the grid stability benefits of the
Wattsmart Battery program in the Study.
Response to IPUC Data Request 47
(a) The WattSmart Battery program is able to provide grid services that provide grid
stability benefits including frequency regulation services, peak load management,
circuit congestion relief, and backup power. The program is designed to allow for
utility integration to allow for automated fast dispatch of enrolled batteries for
frequency response. Additionally, the program allows for longer duration dispatch
providing peak load management and circuit congestion relief. Lastly, the program
is structured to allow customers to maintain a reserve of energy in their battery
systems should backup power be necessary.
(b) Please refer to Confidential Attachment IPUC 47 which provides avoided costs
used for the WattSmart Battery Program for the Company's 2022 Energy
Efficiency and Peak Reduction Annual Report. Grid stability benefits of peak load
PAC-E-23-17/Rocky Mountain Power
March 29, 2024
IPUC Data Request 47
management and circuit congestion relief are reflected in the generation and
distribution capacity benefits.
(c) The WattSmart Battery program and table 4.1 of the export credit study use the
same locational marginal price (LMP) for avoided energy values and the same
transmission and distribution deferral values. The WattSmart battery program
relies on the capacity deferral value used for the Company's interruptible contracts
in Idaho to maintain consistency with previously approved demand response (DR).
(d) Pursuant to the Company's 2022 Energy Efficiency and Peak Reduction Annual
Report, the Company realized the benefits estimated in Confidential Attachment
IPUC 47 based on actual dispatch during the year.
(e) Potential grid stability benefits for systems paired with battery storage are realized
when batteries can be deployed via a distributed battery grid management system.
Customers must enroll in a battery management program and allow a grid operator
to dispatch batteries during a peak load event. Participating customers are
compensated with enrollment and participation incentives.
It is not appropriate to include a grid stability credit/benefit for systems paired with
batteries in an export credit rate (ECR) because only customers who participate in
a battery management program provide grid stability benefits and these customers
are compensated for these benefits through enrollment and participation
incentives. If these benefits were included in an export credit, non-participating
customers would be compensated without providing any benefit and participating
customers would be compensated twice.
(f) The Company did not estimate the grid stability benefits of the Wattsmart Battery
program in the export credit study because these benefits are compensated through
program incentives and do not belong in an export credit. In addition, analysis of
the Wattsmart Battery program was not included in the study scope as defined by
Order No. 34753 in Case No. PAC-E-19-08.
Confidential information is provided subject to protection under IDAPA 31.01.01.067
and 31.01.01.233, the Idaho Public Utilities Commission's Rules of Procedure No. 67
—Information Exempt from Public Review, and further subject to the non-disclosure
agreement(NDA) executed in this proceeding.
Recordholder: Peter Schaffer/Travis Walker
Sponsor: Peter Schaffer/Lee Elder