Item 11- Presentation: AE Transmission — original pdf

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Austin Energy Transmission David Tomczyszyn Vice President Electric System Engineering and Technical Services April 2026 © Austin Energy Item 11Agenda Austin Energy Transmission Overview Planning Process Capital Improvement Program Five-Year Plan Challenges to the Process Resource Generation Plan 2 How We Provide Power To Our Customers T R A N S M I S S I O N D I S T R I B U T I O N 600 Miles of Transmission Lines 12,000 Miles of Distribution Lines 44,000 Overhead Transformers 4,800 Transmission Structures 80 Substations Transmission & Distribution 175,000 Distribution Poles 5,000 Miles of Overhead Lines 46,000 Pad-Mounted & Underground Transformers Transmission Line Summary 69kV 138kV 345kV Total 26 miles 328 miles 276 miles 630 miles 7,000 Miles of Underground Lines 3 Why Doesn’t Austin Energy Talk More Publicly About Transmission Projects? North American Electric Reliability Corporation Critical Protected Infrastructure Maintain Fair and Open Market 4 ERCOT’s Statewide Electric Grid Transmission lines are the superhighways for electric power 5 Transmission Planning: Studies & Projects Reliability Resilience + Transmission line + Autotransformer + Substation + Dynamic/static reactive support ↗ Protection system and redundancy ↗ Protection system communication ↗ Poles / towers ↗ Insulation ↗ Grounding systems ↗ Conductors ○ Long-lead-time equipment Economics + Import capacity + Transmission lines / autotransformers ↗ Transmission line voltage Interconnections ↔ Generation ↔ Other Transmission Service Provider Other + Substation to improve voltage + Substation to accommodate new load 6 Transmission Planning Process in ERCOT Four-tiered system, with Tier 4 requiring the least review and Tier 1 requiring the most. 7 ERCOT’s Transmission Project Timeline 8 Import, Export, and Constraints ~500 MW ~350MW ~50 MW Austin Summer Peak Load: 3110 MW Local Generation: ~800 MW ~1350 MW ~550 MW ~100 MW ~500 MW 9 $500M in Transmission Upgrades Approved in Five-Year Capital Improvement Plan Reconductor Reconductor transmission lines to increase capacity on congested corridors New Import Paths New transmission lines creating new import paths into Austin Upgrade Line Capacity Converting lines from 69kV to 138kV and 138kV to 345kV to increase capacity New Switchyards New switchyards and autotransformers to bring more power into Austin $100M per year in transmission projects approved in the current, five- year CIP Budget, FY2026 – FY2030 60% will directly improve Austin Energy’s import capacity 10 Challenges to the Process Process Time Time to plan, permit, design, procure and construct Supply Chain Long lead times and rising costs of transmission supplies Regulatory Coordination Senate Bill 776 requires a Certificate of Convenience and Necessity (CCN) for easements outside of Austin Scheduling Construction Outages being denied due to insufficient local generation Challenges can add additional time to ERCOT's stated timeline 11 Transmission Import Capacity is Integrated into the Resource Generation Plan to 2035 Leverage Local Solutions Increase Local Generation Incorporate Utility-Scale Batteries Increase Transmission Import Capacity 12 Customer Driven. Community Focused. ©Austin Energy. All rights reserved. Austin Energy and the Austin Energy logo and combinations thereof are trademarks of Austin Energy, the electric department of the City of Austin, Texas. Other names are for informational purposes only and may be trademarks of their respective owners.