Slide 1: 2027 Electric and Natural Gas Integrated Resource Plans
2027 Electric and Natural Gas Integrated Resource Plans Technical Advisory Committee Meeting No. 6 Agenda Monday, March 16, 2026 Virtual Meeting – 1:00 pm to 4:00 pm Pacific Time Topic State Audience • Introduction and Questions from TAC 5 o Sub-Hourly Modeling of Alternative Demand Response o Updat
Slide 2: Introductions 2027 Electric & Gas Integrated Resource Planning
Introductions 2027 Electric & Gas Integrated Resource Planning TAC 6 – March 16, 2026 John Lyons, Ph.D. – Senior Resource Policy Analyst
Slide 3: TAC 6 Agenda
TAC 6 Agenda • Introduction and Questions from TAC 5 • Sub-Hourly Modleing of Alternative Demand Response • Update to Electrification Cost • Aldyl-A Update • Wholesale Electric Price Scenario Forecast • All-Source RFP Update • Economic Forecast & 5-Year Load Forecast • Natural Gas Resource Options &
Slide 4: Meeting Guidelines
Meeting Guidelines • IRP team is in office Monday – Wednesday; also available by email, phone and Teams for questions and comments • Stakeholder feedback responses shared with TAC at meetings, in Teams and in Appendix • Working IRP data posted to Teams • All TAC meetings will be virtual on Teams • D
Slide 5: Virtual TAC Meeting Reminders
Virtual TAC Meeting Reminders • Please mute mics unless speaking or asking a question • Raise hand or use the chat box for questions or comments • Respect the pause • Please try not to speak over the presenter or a speaker • Please state your name before commenting for the note taker • This is a pub
Slide 6: Large Load Update From Earning Call on Feb 25
Large Load Update From Earning Call on Feb 25 • Large load (approximately 35 aMW) plans to leave the system this year • Unknown if will return to the system in the future • A large load entered in an agreement to develop a MOU for future service. • Timing and size to be determined after the MOU is s
Slide 7: South Oregon Electrification Pricing
South Oregon Electrification Pricing • Will use a mix of avoided cost filing capacity cost and energy prices based on conversation with PacifiCorp IRP/EE team • Use Pacific Power Capacity Price ($169/kW-yr) • Use Mid-C Forecast (discussed later today) • Use Avista T&D cost adder (future TAC meeting)
Slide 8: Electrification Costs Per Customer (2026$)
Electrification Costs Per Customer (2026$) - Assumes utility energy efficiency applicable rebate - Assumes appliances replaced at end of life (subtracts equivalent equipment replacement from install cost) - Sales tax is the difference in cost between states - Other represents an impact of clothes dr
Slide 9: Aldyl-A Study and Targeted Voluntary Electrification Timeline
Aldyl-A Study and Targeted Voluntary Electrification (TVE) Timeline Aldyl-A Study • March – preliminary study results available, workshop March 13th with GRC parties to discuss study results, and feedback from interested parties on results • April-May – finalize study and draft report to be filed on
Slide 10: Sub-Hourly Modeling Updates
Sub-Hourly Modeling Updates DER w/ snapback Hourly vs Subhourly Benefit 2024 Dispatch 2025 Dispatch Events Per Year Hourly Revenue 72,914 24,517 RTD Revenue 74,626 25,194 RTD Benefit (Loss) 1,712 677 RTD Benefit (Loss) % 2.3% 2.8% 24 RTD Benefit (Loss) % 4.3% 6.4% 365 RTD Benefit (Loss) % 5.1% 6.2%
Slide 11: TAC 7 and TAC 8 Topics
TAC 7 – Wednesday, April 15, 2026 (13:00 – 16:00 PDT) Topic State Audience Energy Efficiency Savings Since 2025 IRP OR Gas Hybrid Heat Pump Program Update OR Gas Gas Avoided Cost All E&G Long-Run Load Forecast All E&G End-Use Load Forecast All E&G Wholesale Price Forecast – Stochastic WA/ID Electric
Slide 12: TAC 9 and TAC 10 Topics
TAC 9 – Friday, May 15, 2026 (13:00 – 16:00 PDT) Topic State Audience IRP Generation Option Transmission Planning Studies WA/ID Transmission Distribution System Planning within the IRP WA/ID Dist. Transmission Project Example Evaluation WA/ID Transmission QCC Forecast WA/ID Electric Gas Distribution
Slide 13: TAC 11 and TAC 12 Topics
TAC 11 Technical Modeling Workshop – Monday, June 15, 2026 (13:00 – 16:00 PDT) Topic State Audience PRiSM Model Tour All E&G Aurora Resource Adequacy Model Tour WA/ID Electric New Resource Cost Model All E&G TAC 12 Wednesday, July 15, 2026 (TDB) Topic State Audience Load & Resource Balance and Metho
Slide 14: TAC 13 and TAC 14 Topics
TAC 13 – Monday, August 17, 2026 (13:00 – 16:00 PDT) Topic State Audience Preferred Resource Strategy Results All E&G Oregon Non-Pipe Alternatives OR Gas Aldyl-A Analysis and Targeted Voluntary Electrification OR Gas IRP/Progress Report Outlines All E&G Next Steps All E&G TAC 14 – Thursday, Septembe
Slide 15: Other Key Dates
Electric Transmission & Distribution 5-Year Plan – October 7, 2026 (10:00 – 12:00 PDT) Topic State Audience Electric Trans Transmission & Distribution 5-Year Plan WA/OR Electric Other Key Dates • Oct 15, 2026 – Draft Electric IRP Released to TAC • Nov TBD 2026 – Virtual Public Meeting • Noon-1pm • 6
Slide 16: 2027 IRP Market Scenario Update (Draft)
2027 IRP Market Scenario Update (Draft) Technical Advisory Committee Meeting No. 6, March 16th, 2026 Robert Hughes – Resource Planning Analyst
Slide 17: Market Scenario Update
Market Scenario Update • Expected Case (Deterministic) • Low Natural Gas Prices • High Natural Gas Prices • No Washington Climate Commitment Act • No Linkage • No CCA 2
Slide 18: Expected Case (Deterministic) Update
Expected Case (Deterministic) Update Deterministic Price Forecast has been updated to reflect a better supply demand balance Included changes from last TAC • Washington & Oregon Zone were combined into one • BPA & Avista Zone were combined into one • Fix in forecasted demand 3
Slide 19: U.S. West Resource Type Forecast
Draft forecast U.S. West Resource Type Forecast Significant changes 2050 to 2028 (aGW) Solar: + 39.1 Wind: + 27.8 Nat Gas: - 11.9 Coal: - 5.9 Nuclear: + 1.2 Other: + 6.2 Total: + 56.5 4
Slide 20: Northwest Resource Type Forecast
Draft forecast Northwest Resource Type Forecast Significant changes 2050 to 2028 (aGW) Solar: + 5.2 Wind: + 6.0 Nat Gas: - 3.2 Coal: - 0.9 Nuclear: + 1.5 Hydro: + 0.6 Other: + 1.0 Total: + 10.2 5
Slide 21: Aurora Zonal Map
Aurora Zonal Map 6
Slide 22: Aurora Zonal Map with Zones Combined
Aurora Zonal Map with Zones Combined 7
Slide 23: Mid-C Electric Price Forecast
Draft forecast Mid-C Electric Price Forecast • 20 Year Levelized Prices: • $66.72/MWh w/CCA • $64.88/MWh w/o CCA • $63.09/MWh Avista BPA • Forecast includes expected resource additions • Potential for increased prices if new resources don’t come online 8
Slide 24: Mid-C Price Forecast History and Actuals
Mid-C Price Forecast History and Actuals 9
Slide 25: Henry Hub Natural Gas Price Scenarios
Draft forecast Henry Hub Natural Gas Price Scenarios 10 Prices displayed are the 20-year nominal levelized *2025 IRP
Slide 26: Electric Price Forecast
Draft forecast Electric Price Forecast Mid Columbia Washington/Oregon Delivery 11 Prices displayed are the 20-year nominal levelized.
Slide 27: Electric Price Forecast
Draft forecast Electric Price Forecast Mid Columbia Non-Washington/Oregon Delivery 12 Prices displayed are the 20-year nominal levelized.
Slide 28: 2025 All-Source RFP Update
2025 All-Source RFP Update TAC 6 – March 16, 2026 Ryan Finesilver, Resource Marketing Manager
Slide 29: 2025 All-Source RFP Webpage
2025 All-Source RFP Webpage 2 https://www.myavista.com/about-us/integrated-resource-planning/2025-all-source-rfp
Slide 30: Resource Request
Resource Request Up to 415 MW Winter Capacity by 2029 Up to 425 MW Summer Capacity by 2029 Up to 200 aMW of renewable or non-emitting resources Demand response starting as early as 2026 3 Avista 2025 All Source RFP
Slide 31: Timeline and Process
Timeline and Process Status Task Date Complete IE Selection Jan 2025 Avista RFP Evaluation Complete WUTC / IPUC Updates Various Completed Evaluation and Resources Selected Complete WUTC Approval May 2025 for Contracting Complete Issue RFP May 2025 Complete Bidders Conference June 2025 Contracting an
Slide 32: Evaluation Criteria
Evaluation Criteria • Evaluation Methodology (Exhibit D) available on website 5 https://www.myavista.com/about-us/integrated-resource-planning/2025-all-source-rfp
Slide 33: Initial, Short-list and Final Selections
Initial, Short-list and Final Selections • 86 Projects • 69 Supply Side Initial • 17 Demand Response • 31 Projects • 20 Supply Side Short List • 11 Demand Response • 5 Projects • 3 Supply Side Final Selection • 2 Demand Response 6
Slide 34: RFP Final Selections: Montana Wind
RFP Final Selections Montana Wind • Approx 200 MW • 25-Year Power Purchase Agreement • Renewable Energy and Capacity • Utilizes Existing Colstrip Transmission System • Commercial Operation Date: 2029 • Includes Federal Production Tax Credit 7
Slide 35: RFP Final Selections: Natural Gas Peaker Efficiency Improvements
RFP Final Selections Natural Gas Peaker Efficiency Improvements • Approximately 14 MW increase to existing units • Turbine Uprate for 2 Rathdrum CTs • Avista Self-Build project • Commercial Operation Date: ~2028 8
Slide 36: RFP Final Selections: Battery Energy Storage System
RFP Final Selections Battery Energy Storage System (BESS) • 100 MW / 4-Hr BESS • Build-Transfer Agreement • Co-located at Northeast CT • Commercial Operation Date: ~2029 • Capacity contributions to system • Eligible for Federal ITC 9
Slide 37: RFP Final Selections – Demand Response
RFP Final Selections – Demand Response Residential Program • Bring your own Thermostat Program • Up to 20 MW Capacity • Service Agreement Contract • COD: 2026 • Current Stats: In Discussions with Vendor • Capacity levels expected by the 5th year. Not anticipated to be at COD. 10
Slide 38: RFP Final Selections – Demand Response
RFP Final Selections – Demand Response Commercial & Industrial Program • Demand Response Aggregator • Up to 20 MW Capacity • Service Agreement Contract • COD: 2026 • Current Stats: In Discussions with Vendor • Capacity levels expected by the 5th year. Not anticipated to be at COD. 11
Slide 39: Q&A Questions
Q&A Questions Ryan.Finesilver@avistacorp.com Kaylene.Schultz@avistacorp.com 12
Slide 40: 2027 IRP: Economic Conditions and Preliminary Medium-Term Forecasts
TAC Meeting 6 March 16, 2026 2027 IRP: Economic Conditions and Preliminary Medium-Term Forecasts Grant Forsyth, Ph.D. Chief Economist Grant.Forsyth@avistacorp.com
Slide 41: Outline
Outline o Service Area Economy o Medium-Term Energy Forecast (Spring 2026) “This presentation is 40 minutes of a finite life you will never get back.” -Grant Forsyth, April 9, 2024 “This presentation is 120 minutes of a finite life you will never get back.” -Grant Forsyth, March 16, 2026 2
Slide 42: Service Area Economy: Non-Farm Employment Structure
Service Area Economy: Non-Farm Employment Structure Avista WA-ID-OR MSA U.S. Comments Government, 15% Goods, 14% Government, 15% Goods, 14% • Employment structure very similar to the U.S. • Employment dominated by private services. Without service sector growth, very little employment growth will be
Slide 43: Service Area Economy: Non-Farm Employment
Service Area Economy: Non-Farm Employment 6% Comments Year-over-Year, Same Month Seasonally Adj. • Employment growth has slowed, following the U.S. 4% trend. • Growth has been strongest on the ID side. Growth growth in WA and OR looks more like the start of a 2% recession. • Employment growth looks
Slide 44: Service Area Economy: WA-ID Metro Population Growth
Service Area Economy: WA-ID Metro Population Growth 2013-2021: Employment Comments 2008-2012: Employment 2.5% Growth Increasing = Growth Slowing = Slowing In-migration Increasing In-migration • Population growth drives most of our customer growth. 2.0% • Significantly higher than U.S. growth because
Slide 45: Service Area Economy: OR Population Growth
Service Area Economy: OR Population Growth 2008-2012: Employment Growth 2013-2018: Employment Growth Slowing = Slowing In-migration Increasing = Increasing In-migration 1.5% Comments • OR has a similar overall pattern but with some 1.0% differences. • In-migration tends to pick up if regional employ
Slide 46: Service Area Economy: Spokane+Kootenai Residential Units Permitted
Service Area Economy: Spokane+Kootenai Residential Units Permitted 8,000 Comments • Strongly connected to 7,000 population growth. 6,000 • Prices of single-family housing have not declined significantly. The supply side Units Permitted 3,966 5,000 remains constrained. 2,691 1,952 2,327 2,380 2,606 •
Slide 47: Service Area Economy: OR Residential Units Permitted
Service Area Economy: OR Residential Units Permitted 3,000 Comments • Very few apartments permitted in the OR region 2,500 until 2022. Most of those 493 have been in the 1,294 796 Medford/Grant’s Pass area. Units Permitted 1,380 2,000 843 • Prices of single-family housing have not declined 1,500 461
Slide 48: The Energy Forecast: Basic Approach
The Energy Forecast: Basic Approach Time 2026 2030 2031 2050 Medium-Term Long-Term 1) Monthly econometric model by 1) Shifting to end-use modeling. schedule for each customer class. 2) Being handled by CADMUS with a few 2) Customer and UPC forecasts. assumptions from Avista. 3) 20-year moving averag
Slide 49: Medium-Term Forecast: Basic Approach
Medium-Term Forecast: Basic Approach In-house Forecasts Averaged with S&P Connect Certain Employment Population Residential and Growth Growth Commercial Forecast Forecast Forecasts “Consensus” GDP Growth Forecast Industrial Production Certain Industrial and Western Housing UPC Forecasts Start Growth
Slide 50: Economic Assumptions: U.S. GDP Growth Assumptions
Economic Assumptions: U.S. GDP Growth Assumptions 7% 6.0% Comments 6% • Long-run growth is the sum of population growth and labor 5% productivity growth. 4% • U.S. productivity growth has improved but population 2.9% 2.5% 2.9% 2.8% growth may fall faster than 3% 2.6% Annual Growth 2.2% forecasted. 2
Slide 51: Economic Assumptions: Population Growth
Economic Assumptions: Population Growth Medium-Term Long-Term (CADMUS) Avg. Avg. 2.5% Annual Annual IRP Growth, Growth, 2026-2030 2031-2050 2.0% 2027 WA 0.8% 0.3% 1.5% 2027 ID 1.8% 1.2% Annual Growth 2027 OR 0.6% 0.2% 1.0% Comments 0.5% • From 2031 on, the time-path reflects S&P 500 population forec
Slide 52: Medium-Term Energy Forecast: Native Load
Medium-Term Energy Forecast: Native Load Avg. Annual IRP Growth, 2026- 1,180 1,176 2030* 2025 IRP 0.22% 1,170 1,168 2027 IRP 0.70% * Spring 2024 forecast in 2025 IRP 1,160 Average Megawatts 1,156 Comments 1,150 1,150 1,146 1,147 1,147 • The difference reflects 1,144 1,143 1,145 declining gas penetra
Slide 53: Medium-Term Energy Forecast: Native Load since 2005
Medium-Term Energy Forecast: Native Load since 2005 1,190 +23 aMW Comments 1,170 • Prior to 2021/2022, the housing bubble period was the last significant 1,150 +35 aMW step up in native load. 1,130 • The 2008-2020 period Average Megawatts saw little growth until the pandemic period. 1,110 • Dashed b
Slide 54: Medium-Term Retail Forecast: Retail Load since 2012
Medium-Term Retail Forecast: Retail Load since 2012 2025 Load Share 700 430 420 37% 680 Washington Average Megawatts 410 63% Idaho Average Megawatts 660 400 ID WA 640 390 380 620 370 600 360 580 350 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 WA Ret
Slide 55: Medium-Term Retail Forecast: WA Gas Load since 2020
Medium-Term Retail Forecast: WA Gas Load since 2020 250 2025 Load Share 25% 28% 200 47% Therms in Millions 150 OR WA ID 100 50 0 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 WA Transport Only WA Firm+Interruptible, No Transport 16
Slide 56: Medium-Term Retail Forecast: ID Gas Load since 2012
Medium-Term Retail Forecast: ID Gas Load since 2012 120 2025 Load Share 25% 28% 100 80 Therms in Millions 47% OR WA ID 60 40 20 0 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 ID Firm+Interruptible, No Transport ID Transport Only 17
Slide 57: Medium-Term Retail Forecast: OR Gas Load since 2012
Medium-Term Retail Forecast: OR Gas Load since 2012 120 2025 Load Share 25% 100 28% 80 Therms in Millions 47% OR WA ID 60 40 20 0 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 OR Firm+Interruptible, No Transport OR Firm Only OR Transport Only 18
Slide 58: Questions?
Questions? 19
Slide 59: Natural Gas Resource Options & Price Forecast
Natural Gas Resource Options & Price Forecast TAC 6 – March 16, 2026 Michael Brutocao, Natural Gas Planning Manager
Slide 60: Natural Gas Demand and Resource Options
Natural Gas Demand and Resource Options • Natural Gas Basin • AECO Reduced Demand & Fuel • Malin • Electrification • Natural Gas • Rockies • Energy • Alternative • Stanfield Efficiency Fuels • Station 2 • Demand • Sumas Response • Hydrogen • Blue • Green • Turquoise Compliance Storage & • RNG Mechan
Slide 61: The full ICF report is available in the Avista 2025 Natural Gas IRP Appendix
The full ICF report is available in the Avista 2025 Natural Gas IRP Appendix, beginning at page 232. https://www.myavista.com/-/media/myavista/content-documents/about-us/our-company/irp-documents/natural-gas-irp-documents/2025/2025- 3 appendix.pdf?la=en&sc_lang=en
Slide 62: Refresher on Prices
Refresher on Prices Expected prices are broken down between northwest and national technical potential (ICF) • All prices consider Inflation Reduction Act (IRA) incentives where applicable. • These prices assume a first mover access to alternative fuels. • Prices are from the Northwest for each alte
Slide 63: Market Updates to ICF Models
Market Updates to ICF Models Prices shown are in real 2022 USD. 5 AEO Next Release Date: April 8, 2026
Slide 64: Policy Updates to ICF Models: One Big Beautiful Bill
Policy Updates to ICF Models: One Big Beautiful Bill • Limited, if any, effect on long-term pricing forecasts • Section 45Z • Clean fuel production tax credit extended 2027 → 2029 • Relating to RNG, this guidance was reissued in draft form and there remain insufficient details for developers to esti
Slide 65: Natural Gas Demand and Resource Options
Natural Gas Demand and Resource Options • Natural Gas Basin • AECO Reduced Demand & Fuel • Malin • Electrification • Natural Gas • Rockies • Energy • Alternative • Stanfield Efficiency Fuels • Station 2 • Demand • Sumas Response • Hydrogen • Blue • Green • Turquoise Compliance Storage & • RNG Mechan
Slide 66: DRAFT Price Forecasts – Hydrogen
DRAFT Price Forecasts – Hydrogen (Nominal, 20-Year Levelized $/MMBtu) 8
Slide 67: Natural Gas Demand and Resource Options
Natural Gas Demand and Resource Options • Natural Gas Basin • AECO Reduced Demand & Fuel • Malin • Electrification • Natural Gas • Rockies • Energy • Alternative • Stanfield Efficiency Fuels • Station 2 • Demand • Sumas Response • Hydrogen • Blue • Green • Turquoise Compliance Storage & • RNG Mechan
Slide 68: DRAFT Price Forecasts – Renewable Natural Gas
DRAFT Price Forecasts – Renewable Natural Gas (Nominal, 20-Year Levelized $/MMBtu) 10
Slide 69: Natural Gas Demand and Resource Options
Natural Gas Demand and Resource Options • Natural Gas Basin • AECO Reduced Demand & Fuel • Malin • Electrification • Natural Gas • Rockies • Energy • Alternative • Stanfield Efficiency Fuels • Station 2 • Demand • Sumas Response • Hydrogen • Blue • Green • Turquoise Compliance Storage & • RNG Mechan
Slide 70: DRAFT Price Forecasts – Synthetic Methane
DRAFT Price Forecasts – Synthetic Methane (Nominal, 20-Year Levelized $/MMBtu) 12
Slide 71: Natural Gas Demand and Resource Options
Natural Gas Demand and Resource Options • Natural Gas Basin • AECO Reduced Demand & Fuel • Malin • Electrification • Natural Gas • Rockies • Energy • Alternative • Stanfield Efficiency Fuels • Station 2 • Demand • Sumas Response • Hydrogen • Blue • Green • Turquoise Compliance Storage & • RNG Mechan
Slide 72: DRAFT Price Forecasts – Carbon Capture, Utilization & Sequestration
DRAFT Price Forecasts – Carbon Capture, Utilization & Sequestration (Nominal, 20-Year Levelized $/MMBtu) 14
Slide 73: DRAFT Price Forecasts – Renewable Thermal Credits
DRAFT Price Forecasts – Renewable Thermal Credits (Nominal, $/MMBtu) 15
Slide 74: Refresher on Volumes
Refresher on Volumes Expected volumes are broken down between Northwest and National technical potential. • These volumes assume a first mover access to alternative fuels. Company 2023 # of Meters Share AVA 379,223 15.83% • Weighted by US population for states where some form of climate policy is in
Slide 75: DRAFT Available Supply Forecast by Feedstock Production Potential
DRAFT Available Supply Forecast by Feedstock Production Potential Company 2023 # of Meters Share AVA 379,223 15.83% CNG 316,929 13.23% NWN 799,250 33.37% PSE 900,000 37.57% Total NW 2,395,402 100.00% 17