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HomeMy WebLinkAbout20240705IPC to Staff 11-22 (Redacted).pdf 0-10RHO POWER. RECEIVED DONOVAN WALKER Frday, July 5, 2024 Lead Counsel IDAHO PUBLIC dwalker(a)idahopower.com UTILITIES COMMISSION July 5, 2024 VIA ELECTRONIC FILING Commission Secretary Idaho Public Utilities Commission 11331 W. Chinden Blvd., Bldg 8, Suite 201-A (83714) PO Box 83720 Boise, Idaho 83720-0074 Re: Case No. IPC-E-24-16 In the Matter of Idaho Power Company's Application for a Certificate of Public Convenience and Necessity for the Boise Bench Battery Storage Facility Dear Commission Secretary: Attached for electronic filing please find Idaho Power Company's Response to the Second Production Request of the Commission Staff to Idaho Power Company. The confidential attachments will be sent separately to the parties who sign the Protective Agreement. Please feel free to contact me directly with any questions you might have about this filing. Very truly yours, Donovan E. Walker DEW:sg Attachments CERTIFICATE OF ATTORNEY ASSERTION THAT INFORMATION CONTAINED IN AN IDAHO PUBLIC UTILITIES COMMISSION FILING IS PROTECTED FROM PUBLIC INSPECTION Application for a Certificate of Public Convenience and Necessity for the Boise Bench Battery Storage Facility IPC-E-24-16 The undersigned attorney, in accordance with Commission Rules of Procedure 67, believes that Idaho Power Company's Response to the Second Production Request of the Commission Staff to Idaho Power Company and Attachments, contain information that Idaho Power Company and a third party claims are confidential trade secret as described in Idaho Code § 74-101, et seq., and/or § 48-801, et seq. As such, they are protected from public disclosure and exempt from public inspection, examination, or copying. DATED this 5t" day of July 2024. Donovan Walker Counsel for Idaho Power Company DONOVAN E. WALKER (ISB No. 5921) Idaho Power Company 1221 West Idaho Street (83702) P.O. Box 70 Boise, Idaho 83707 Telephone: (208) 388-5317 Facsimile: (208) 388-6936 dwalker(o-)idahopower.com Attorney for Idaho Power Company BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION IN THE MATTER OF IDAHO POWER ) COMPANY'S APPLICATION FOR A ) CASE NO. IPC-E-24-16 CERTIFICATE OF PUBLIC CONVENIENCE ) AND NECESSITY FOR THE BOISE ) IDAHO POWER COMPANY'S BENCH BATTERY STORAGE FACILITY. ) RESPONSE TO THE CONFIDENTIAL SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY COMES NOW, Idaho Power Company ("Idaho Power" or "Company"), and in response to the Second Production Request of the Commission Staff ("Commission" or "Staff") dated June 14, 2024, herewith submits the following information: IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 1 REQUEST FOR PRODUCTION NO. 11: Please describe any differences in the anticipated operational dispatch of the Boise Bench Battery Energy Storage System ("BESS") between summer and winter peak seasons. RESPONSE TO REQUEST FOR PRODUCTION NO. 11: The Boise Bench BESS is a flexible resource, as are all BESS systems on Idaho Power's system, and will be dispatched throughout the year based on system needs to reliably serve customers. In general, the Company assumes a BESS will operate through one complete charge and discharge cycle each day regardless of the season and can be adapted to support real- time needs. The Boise Bench BESS will generally be dispatched daily based on system conditions and needs, although there may be times when the resource discharge is not needed as other resources are generating and the system has sufficient resources to serve customer load. Idaho Power's system peak occurs during the summer months, and in the summer, it is anticipated that the Company will typically charge the Boise Bench BESS in the early morning or midday hours and discharge the BESS capacity in the evening hours. During the winter, when Idaho Power has higher loads both in the morning and in the evening, Idaho Power would typically plan to charge either overnight or in midday so that the BESS is available to discharge either in the early morning or evening hours, or potentially both, depending on the need. The response to this Request is sponsored by Eric Hackett, Projects and Resource Development Director, Idaho Power Company. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 2 REQUEST FOR PRODUCTION NO. 12: Please provide the RCAT model results showing the charge and discharge hours for the winter months used to inform the "Most Valuable Hours" table in Confidential Attachment 3 to Production Request No. 1. Please note all hours where the battery is modeled as unable to charge. ** Note: In the response, please highlight confidential information. RESPONSE TO REQUEST FOR PRODUCTION NO. 12: The Idaho Power Evaluation Team provided the Most Valuable Hours table in Exhibit G to the 2026 All Source Request for Proposals ("RFP")to all bidders as guidance on the Company's timing of need. Bidders then completed the Most Valuable Hours table with the anticipated project contribution in various hours for their submission to the Idaho Power Evaluation Team. While bidders provided how the various resources could be expected to meet the Company's most valuable hours, the Idaho Power Evaluation Team did not utilize this information for modeling purposes. Instead, the Idaho Power Evaluation Team modeled each project in the Reliability and Capacity Assessment Tool ("RCAT") and AURORA for bid evaluation. Both the RCAT and AURORA utilize dispatch algorithms to model Battery Energy Storage Systems ("BESS"), meaning the charge and discharge hours vary and will not be a direct match to the hours reflected in the "Most Valuable Hours" table provided by the bidder. Once a portfolio buildout is established, the selected resources are input into the RCAT. The RCAT combines all stand-alone 4-hour BESS in the dispatch algorithm to maximize the benefit the technology can provide to the system. Figures 1 and 2 below show the average hourly charge and discharge, respectively, for all stand-alone 4-hour BESS by month. The data in these figures are a direct export from the RCAT and were IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 3 utilized to calculate the reduction of 116 MW' in the 2026 capacity deficiency of 236 MW due to the addition of the Boise Bench BESS. For clarity, the stand-alone 4-hour BESS projects included in this RCAT simulation total approximately 500 MW of nameplate capacity. Please note that the RCAT is a capacity-only model and is currently set to cycle all 4-hour BESS projects once per day, even in months when there is no significant capacity need. Figure 1. Average hourly charge by month for all stand-alone 4-hour BESS in 2026 from RCAT 50 January Charge 500 Febnn 400 400 ry Charge March Charge April Charge 2 � •fff •�. II • T ef} 200 l fTs 400 }TIT }I T T 300 l• 300 T 150 IIIIII (IIII 300 ♦IIII} IIIII Its IIIIII IIIIII IIIIII •IIIII }IIIII zoa iiiiii 200 too ii iiiiii 200 iiiiii iiiiii• iiiiiiT ell 50 TII Ili 100 TIIIIIIIIIIIIf 1oa s}Tfff TII 100 }I,I I,I I,I I• •IIII IIIIIIII IIIIII IIIIIIIIT fffffT IIIIIIIIIITss• 0 0 0 0 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 300 May Charge 300 June Charge 500 July Charge 400 August Charge f 250 250 T • fel aoa sT 30o?fT f'I• 200 ell I•�� 200 •! } }I, f eI 300 150 150 ♦ a 200 a eTiiiiiiii l 200 iiiiii •liiiiii 100 •s ellllllllli 100 • iillllllll IIIIIII ellllllll• •fffll Illlllllllle IIIIIIIIIIII a IIIIIII 100 IIIIIIIIII 50 IIIIII •IIIIIIIIIIII 50 •IIIIIIIIIIII TIa• 100 •IIIIIIII ellllllllll9 I II•Illlllllllllle Illlllllllllllllle Illlllllle IIIIIIIIIIII•0 0 0 0 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 September Charge Dubber Charge November Charge December Charge 300 400 00 • 300 T 250 Is Is III III 250 l e TT l T 300 250 200 200 200 ITs IIII• }IIIII IIIIII sT IIIIII }IIIII IIIIII 'IIII 150 ••• !• 200 • 150 •}}fff 150 II III IIII asses 100 s •s I'i I'i I'i I'i 100 I'i I'i I'i I'i I'I 100 I'i I'i I'i 100 Ili iiiiii iiii iiiiii} I I 50 illlllllllie Illllllle 50 IIIIII elllllll 50 I'i IIII IIIIII• Iliiil••a. 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 See Ellsworth Direct Testimony page 25. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY-4 Figure 2. Average hourly discharge by month for all stand-alone 4-hour BESS in 2026 from RCAT January Discharge February Discharge March Discharge April Discharge 200 250 300 250 150 f •� 200 250 - 200 f! fiif f • 200 ? • fi 1so TT• fll• T 150 if i• 100 i i• 150 •iT f • • f 100 f • 100 • • ! • • • •i •i • 100 f it 50 I!!I T T • •IIII •♦ III •IIII I• • III! IIIII IIII IIT • 50 •f•flllll •, fflll If 50 • •IIIII• •f fl 50 ♦ • IIII♦ fTf •!IIIII IIII IIITIIIIIIII♦ IIIIIIIIITI T?IIIII I,Tllllllla Tf•• TTIIIIIIII•III•• III II ... o ... o .. .. o .. ..... .., 0 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 250 May Discharge 400 June Discharge 400 July Discharge 400 August Discharge • i• 200 T 300 ?l 300 300 T • 150 i i i i? •i i f i i i III IIIT •III • i i i♦ zoo 20o i i i i 200 100 if iiiii f'I II T iiii •iiii • Til •iiiii iiii• ?iTiiii •iiiii! if •fi' Nff♦liiiii 100 fii 100 fii ma 50 ilTli if •fii iiii f f it iT •iiillli iiiii if•II iiii •••••Tlff•f••• •Ti iii • •ii • •• •li iiiii 0 o a o 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 September Discharge October Discharge Nowmber Discharge December Discharge 300 0 250 • 150 150 f 250 200 T li ♦T• fii T•ii iii Ti •i ii zoo IT l iT 100 l l f? Ti 100 • f •iif o 150 T T I I I• s• T•1 •II III lI iI IlI II II• f I I I I1I• 100 • 100 50 Too l TT I 50 TITIII iIII II II II II II•II♦I lI I.II.IIfhII III iIII lIIIi lI�IIif.I�IIi • ?• •I I I I I I I I I •l I f I I I I I I 50 • f l l••I I I I I I I I I I I I I I50 IT•••l I I Ifl l l l l l l I I I I I I I I l l i i i l l lTlf?i? TI i i i i? ?••••I l i i l i i i i i• i i i i l l i l l i i i l i i i i i i i i l l l i i i i l l l l 0 o al o .i IIi •l• o s 10 15 zo zs o s m 15 zo zs o s m 15 20 25 o s 10 15 20 25 As shown by Figure 2, the discharge shape of the stand-alone 4-hour BESS closely follows the "Most Valuable Hours" table provided in Exhibit G to the RFP. The response to this Request is sponsored by Andres Valdepena Delgado, System Consulting Engineer, Idaho Power Company. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 5 REQUEST FOR PRODUCTION NO. 13: Please explain if the assumed round trip efficiency accounts for variations due to weather and associated parasitic loads. RESPONSE TO REQUEST FOR PRODUCTION NO. 13: The minimum round trip efficiency guarantee is a value established with the manufacturer and is not adjusted due to variations in weather. While weather likely plays a role in actual measured round-trip efficiency, the guaranteed minimum does not fluctuate as a function of the weather. Parasitic load may or may not be factored into the round-trip efficiency guarantee value depending on the manufacturer's design specifications and the site parameters. For example, if the site parameters provide auxiliary load from an adjacent distribution line service point, the guaranteed round-trip efficiency would be higher because parasitic/auxiliary distribution service is not consumed within the measurement of round- trip efficiency. Conversely, some systems have an integrated inverter and transformer within the energy segments, and thus the round-trip efficiency would be lower to account for the parasitic load. More importantly, the total capacity that the Boise Bench BESS is guaranteed to provide to the Idaho Power system during a discharge is 150 MW during a four-hour span, regardless of the round-trip efficiency value. The response to this Request is sponsored by Eric Hackett, Projects and Resource Development Director, Idaho Power Company. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 6 REQUEST FOR PRODUCTION NO. 14: In the testimony of Company witness Ellsworth, he describes a relation between solar photovoltaic ("PV") systems and energy storage systems. Ellsworth at 26. Please provide the ratio of solar to storage resources on the Company's system, the Effective Load Carrying Capacity ("ELCC") of solar resources, and the ELCC of battery resources for the following cases: a. Company's current system; b. With the inclusion of the 150 MW BESS; c. With the addition of the forecasted 525 MW solar PV resource described in Ellsworth at 26; d. With the addition of any other near-term resource additions; e. With all of the above. RESPONSE TO REQUEST FOR PRODUCTION NO. 14: The table below includes the ELCC results and corresponding solar to storage ratios for the specified cases in parts (a) through (e) above. Please note that Idaho Power assumes the current system to reflect contracted near-term resource additions, meaning the results for part (a) and (d) of this request are the same. PV BESS PV to Part Description ELCC ELCC BESS Ratio a. Current System ("CS") 54.1% 82.2% 1.76 b. 2 CS + 150 MW BESS 54.9% 71.8% 1.24 C. 2 CS + 525 MW PV 38.7% 97.8% 3.22 d. 1 CS 54.1% 82.2% 1.76 e. 2 CS + 150 MW BESS + 525 MW PV 43.7% 93.8% 2.27 Cases assumed a 2026 load and resource year. 2 Cases assumed a 2027 load and resource year. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 7 The response to this Request is sponsored by Andres Valdepena Delgado, System Consulting Engineer, Idaho Power Company. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 8 REQUEST FOR PRODUCTION NO. 15: In response to Production Request No. I - Confidential Attachment 3 at 3, the Bid states that the batteries can be recharged in approximately . Please answer the following questions: a. Please clarify if this is the minimum time needed to recharge. b. Please explain if dispatch operations assume a different recharge time than the stated recharge time. c. Please provide the average duration of the recharging window in each month. d. Please explain how the charge rate may affect battery degradation, cycle life, and round-trip efficiency. ** Note: In the response, please highlight confidential information. RESPONSE TO REQUEST FOR PRODUCTION NO. 15: a. The general statement is accurate in relation to a typical four-hour BESS system. BESS systems typically take slightly longer to charge than the expected discharge timeframe. Because the round-trip efficiency is less than 100 percent, additional megawatt-hours are required to charge the BESS than can be expected to discharge, thus the timeframe to charge to a particular capacity takes longer than the expected discharge. If a four-hour BESS was at a zero state of charge, it would take four to five hours charging at full capacity to reach a full state of charge. That said, the BESS is not required to always be charged to a full state of charge nor is it required to always discharge at a full four hours at max capacity. For example, if the BESS were only needed to discharge for one hour at the maximum capacity, the charge timeframe may be less than two hours. b. No. The BESS is assumed to need four to five hours charging at full capacity to reach a full state of charge. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 9 c. With the assumption of 365 full charge and discharge cycles annually, the assumed time to charge is approximately four to five hours daily depending on the system discharge need in each day. This is highly flexible and may be adapted daily, monthly, and annually based on system conditions. As an example, if the BESS is fully charged on one day with the four-to-five-hour charge time, and is fully discharged that same day, it would need to be charged again the next day before it can be used. On the other hand, if the BESS is fully charged and then is only partially discharged, then it would not need as much charging on a following day. Further, there may be some days, particularly in shoulder seasons, where the BESS may not be needed every single day. Finally, it is worth noting the point of interconnection limits the amount of capacity that can flow to or from the BESS at any given time. The BESS simply cannot be charged faster than the product of the point of interconnection backfeed capacity limitation and the time it takes to bring the BESS to a full state of charge. d. The contract with the BESS manufacturer generally sets forth guaranteed performance characteristics of the BESS, which are based on and address many factors, including the assumed limitation of the charge rate, round trip efficiency, and maximum cycles throughput per year. Therefore, the Company anticipates battery degradation, cycle life, and round-trip efficiency will follow the manufacturers' performance characteristics. The response to this Request is sponsored by Eric Hackett, Projects and Resource Development Director, Idaho Power Company. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 10 REQUEST FOR PRODUCTION NO. 16: In response to Production Request No. 1 - Confidential Attachment 3 at 6, the Company describes that the discharge cycles from months without critical hours can be shifted to months with both morning and evening sets of valuable hours. Please provide workpapers quantifying the shoulder month cycles and showing how they are redistributed. ** Note: In the response, please highlight confidential information. RESPONSE TO REQUEST FOR PRODUCTION NO. 16: The referenced statement is suggesting that the BESS is not strictly limited to one cycle per day, but rather 365 cycles per year, suggesting only that in some months the BESS could be cycled twice per day as long as the total annual cycle count does not exceed 365. The response to this Request is sponsored by Eric Hackett, Projects and Resource Development Director, Idaho Power Company. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 11 REQUEST FOR PRODUCTION NO. 17: In response to Production Request No. 1 - Confidential Attachment 3 at 3, the Bid states, ' -". Please specify the amount of the 365 annual discharge cycles anticipated to be used ** Note: In the response, please highlight confidential information. RESPONSE TO REQUEST FOR PRODUCTION NO. 17: The Boise Bench BESS was selected on the final short list as a least-cost, least-risk resource necessary to fill the identified capacity deficits in 2026, providing capacity to meet peak load needs. The Company modeled the BESS as prioritizing net-demand hours for discharge, meaning AURORA generally prioritizes charging the BESS at combined low demand and high renewable output hours of the day, and discharging the BESS at high demand and low renewable output hours. As described in the Response to Request for Production No. 7, the Company intends to charge the BESS when it is most economical to do so and to ensure the BESS is charged in time to be available to discharge in peak load hours or the hours of highest need. The Company's Evaluation Team has not modeled or otherwise forecasted frequency of use of this resource for The response to this Request is sponsored by Camille Christen, Resource Acquisition, Planning, and Coordination Manager, Idaho Power Company. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 12 REQUEST FOR PRODUCTION NO. 18: In response to Production Request No. 1 - Confidential Attachment 3 at 6, the "Most Valuable Hours" table shows discharge during hours of - in summer months. Please explain why the Company Bid selected battery dispatch during a time frame when renewable resources are still expected to be generating as opposed to hours after sundown. a. Additionally, please explain how the Company Bid models capacity availability of the 4-hour Boise Bench BESS resource across ** Note: In the response, please highlight confidential information. RESPONSE TO REQUEST FOR PRODUCTION NO. 18: As referenced in the Response to Request for Production No. 12, the specified "Most Valuable Hours" table for the Boise Bench BESS was prepared by the Idaho Power Internal Bid Team, separate and independent from the Idaho Power Evaluation Team. The table appears to show how the Boise Bench BESS could be dispatched to meet the "Most Valuable Hours" identified in Exhibit G of the 2026 RFP. Exhibit G identified the critical need hours for Idaho Power's deficit and indicated the Company will favor resources that can meet these identified hours. Thus, the Response to Production Request No. 1 - Confidential Attachment 3 at 6 illustrated how the resource could meet those RFP-identified "Most Valuable Hours." a. See Response to Request for Production No. 12 for an explanation of the modeling assumptions related to the "Most Valuable Hours." The response to this Request is sponsored by Andres Valdepena Delgado, System Consulting Engineer, Idaho Power Company. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 13 REQUEST FOR PRODUCTION NO. 19: In response to Production Request No. 1 - Confidential Attachment 3 at 6, the "Most Valuable Hours" table shows discharge during the evening most valuable hours . Please explain why the Company Bid prioritized discharge during the evening period over the morning period. ** Note: In the response, please highlight confidential information. RESPONSE TO REQUEST FOR PRODUCTION NO. 19: The table in the referenced Confidential Attachment was prepared by the Idaho Power Bid Team, without input from or direct knowledge of the Idaho Power Evaluation Team. Regardless, the Evaluation Team's understanding is the table shows when the resource could be discharged. See the Response to Request for Production No. 12 for a discussion on how modeling of the charging and discharging of the Boise Bench BESS was performed. The response to this Request is sponsored by Eric Hackett, Projects and Resource Development Director, Idaho Power Company. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 14 REQUEST FOR PRODUCTION NO. 20: Company witness Hackett describes that the Company received 21 BESS resource bids for the 2026 RFP. Hackett at 27. Please provide a table similar to the one contained in the Company's response to Production Request No. 4 for each of the RFP bids for BESS resources. Additionally, for each bid please also include the proposed operational date, cost estimates, battery supplier, location and total MW that could have been provided by the BESS resource. RESPONSE TO REQUEST FOR PRODUCTION NO. 20: See the Company's Response to Staff's Request No. 20 — Confidential Attachment. Please note, only the two self-build BESS resources have the level of detail provided in Production Request No. 4 because the remaining projects were either Build Transfer Agreements ("BTA"), projects are lump-sum bids, or Battery Storage Agreements ("BSA"), projects that are owned and operated by third-party entities. The details for the self-build BESS resources are presented on the tabs labeled IPC75BEAP10026 and IPC76BEAP15026. Although the Company cannot provide the level of detail provided in Production Request No. 4 for the 21 bids referenced, Idaho Power instead included the total capital cost and the levelized cost of capacity ("LCOC") of the BTA bids, and the first-year annual payment, total estimated contract life payments, and the LCOC for the BSA bids. The RFP did not require bidders to provide battery supplier information as part of their bid therefore that information is not available. Please note, the 21 bids referenced were bids that made up the initial shortlist, therefore the bid information was provided prior to any pricing updates. For comparison purposes, Idaho Power has also provided the initial pricing information for those bids that moved on to the final shortlist. The response to this Request is sponsored by John Wonderlich, Finance Team Leader II, Idaho Power Company. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 15 REQUEST FOR PRODUCTION NO. 21: Please provide supporting documentation for the "Civil Construction, Site Work, Underground Conduit, and Grounding, Fencing, Concrete Foundations" cost estimate of listed in the table in the Company's response to Production Request No. 4. RESPONSE TO REQUEST FOR PRODUCTION NO. 21: The total cost estimate for the Boise Bench BESS utilized for modeling of the final short list, reflective of the pricing revisions submitted in September 2023, is , which includes BESS equipment, interconnection facilities costs, Balance of System ("BOS") costs, Allowance for Funds Used During Construction ("AFUDC"), and taxes. See the Bid Submittal tab of the Company's Response to Staff's Request for Production No. 21 — Confidential Attachment for the cost detail provided in the bid submitted. The estimate for the BOS utilized to develop the total estimate is further detailed on the BOS Estimate tab which includes the components of the quantification that make up the BOS before taxes and AFUDC. Finally, the DR 4 Submittal tab shows how Idaho Power initially split the total estimate of into the requested line items from the Company's Response to Staff's Request for Production No. 4 because the bid submittal did not provide the necessary level of detail. The BOS was spread to the cost categories based on the percentages obtained from the cost estimate prepared in Response to Production Request No. 11 in Case No. IPC-E-23-20 and the basis for the cost estimate provided in Response to Production Request No. 4 in this proceeding. Subtracting the BESS Equipment and the Interconnection Facilities costs from the total estimate equates to an all-inclusive BOS cost estimate of , which includes taxes and AFUDC. The response to this Request is sponsored by Eric Hackett, Projects and Resource Development Director, Idaho Power Company. IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 16 REQUEST FOR PRODUCTION NO. 22: As follow up to the Company's response to Production Request No. 4, please explain why the Electrical Construction and BESS Installation cost estimates are both-. RESPONSE TO REQUEST FOR PRODUCTION NO. 22: Please see Response to Request for Production No. 21 for an explanation of how the BOS cost estimate was prepared. The Electrical Construction and BESS Installation costs included in Response to Production Request No. 11 in Case No. IPC-E-23-20 were approximately 10 percent of the total BOS estimate. Applying approximately 10 percent to the total Boise Bench BESS BOS cost estimate of results in Electrical Construction costs of - and BESS Installation costs of The response to this Request is sponsored by Eric Hackett, Projects and Resource Development Director, Idaho Power Company. DATED at Boise, Idaho this 5t" day of July 2024. DONOVAN E. WALKER Attorney for Idaho Power Company IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 17 CERTIFICATE OF SERVICE I HEREBY CERTIFY that on the 5th day of July, 2024, 1 served a true and correct copy of Idaho Power Company's Response to the Second Production Request of the Commission Staff upon the following named parties by the method indicated below, and addressed to the following: Commission Staff Hand Delivered Chris Burdin U.S. Mail Deputy Attorney General Overnight Mail Idaho Public Utilities Commission FAX 11331 W. Chinden Blvd., Bldg No. 8 FTP Site Suite 201-A (83714) X Email Chris.Burdin(cr puc.idaho.gov PO Box 83720 Boise, ID 83720-0074 Micron Technology, Inc. Hand Delivered Austin Rueschhoff U.S. Mail Thorvald A. Nelson Overnight Mail Austin W. Jensen FAX Holland & Hart LLP X Email darueschhoff(a�hol land ha rt.corn 555 17th Street, Suite 3200 tnelson(a)hol land hart.com Denver, CO 80202 awjensen hollandhart.com aclee(a)hol land hart.com mamcmiIlen(a-).hol land hart.com Micron Technology, Inc. Hand Delivered Jim Swier U.S. Mail 8000 S. Federal Way Overnight Mail Boise, ID 83707 FAX X Email jswier micron.com Clean Energy Opportunities for Idaho Hand Delivered Kelsey Jae U.S. Mail Law for Conscious Leadership Overnight Mail 920 N. Clover Dr. FAX Boise, ID 83703 X EMAIL Kelsey(a-)_kelseyjae.com IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 18 Courtney White Hand Delivered Mike Heckler U.S. Mail Clean Energy Opportunities for Idaho Inc. Overnight Mail 3778 Plantation River Dr., Suite 102 FAX Boise, Idaho 83703 X EMAIL Courtney(c)cleanenergyopportunities.com mike(a�_cleanenergyopportunities.com Stacy Gust, Regulatory Administrative Assistant IDAHO POWER COMPANY'S RESPONSE TO THE SECOND PRODUCTION REQUEST OF THE COMMISSION STAFF TO IDAHO POWER COMPANY- 19 BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION CASE NO. IPC-E-24-16 IDAHO POWER COMPANY CONFIDENTIAL REQUEST NO. 20 ATTACHMENT NO. 1 SEE ATTACHED SPREADSHEET BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION CASE NO. IPC-E-24-16 IDAHO POWER COMPANY CONFIDENTIAL REQUEST NO. 21 ATTACHMENT NO. 1 SEE ATTACHED SPREADSHEET