Xcel Energy Inc. · NASDAQ:XEL

Xcel Energy — Technical Presentation (June 2020)

22 slides from Xcel Energy's technical presentation, Jun 16, 2020

1. Slide 1: Hosting Capacity Criteria, Inputs and Thresholds

   Hosting Capacity Criteria, Inputs and Thresholds Stakeholder Workshop #2 June 16, 2020

2. Slide 2: Presenter

   PRESENTER Chris Punt, Xcel Energy - DER Integration Manager 2 © 2020 Xcel Energy

3. Slide 3: Objectives

   OBJECTIVES • Discuss: o Drivers of feeder model updates for Hosting Capacity Analysis o Inputs and assumptions in DRIVE (Distribution Resource Integration and Value Estimation) o Threshold values used in DRIVE • Discuss and gather feedback • Discuss next steps 3 © 2020 Xcel Energy

4. Slide 4: DRIVE Process Step

   DRIVE Process Step 4 © 2020 Xcel Energy

5. Slide 5: Feeder Modeling Updates

   Feeder Modeling Updates Remodeling a feeder means creating a new model of our distribution system that reflects its most current state at the time of our analysis • 2019 efficiency improvement: Rather than remodel feeders every year whether they changed or not, we decided to remodel at least every t

6. Slide 6: DRIVE Process Step

   DRIVE Process Step 6 © 2020 Xcel Energy

7. Slide 7: DRIVE and Impact Study Alignment

   DRIVE and Impact Study Alignment • We align the thresholds used in DRIVE with the ones we use in our System Impact Studies for interconnection o Allows for better consistency in results o Provides another reference point for DRIVE thresholds • Not all available DRIVE thresholds are used in System Im

8. Slide 8: DRIVE Inputs and Assumptions

   DRIVE Inputs and Assumptions • Year ahead feeder configuration • Peak load power flow case • Daytime Minimum Load power flow case • Distributed Energy Resource o100% output oNew DER is PV oNew DER at 98% power factor (absorb VARs) o100% output change for over-voltage and voltage deviation oCentraliz

9. Slide 9: DRIVE Thresholds

   DRIVE Thresholds • Primary Over-Voltage • Primary Voltage Deviation • Regulator Voltage Deviation • Thermal for DER Output • Additional Element Fault Current • Breaker Relay Reduction of Reach • Unintentional Islanding 9 © 2020 Xcel Energy

10. Slide 10: Presenter

    PRESENTER Ed Shannon, Xcel Energy - Principal DER Engineer 10 © 2020 Xcel Energy

11. Slide 11: Threshold – Primary Over-Voltage

    Threshold – Primary Over-Voltage Description: Feeder voltage at any location on the feeder not to go above a specified voltage magnitude Value: 105% (126 Volts) Basis: ANSI C84.1 Range A 11 © 2020 Xcel Energy 11

12. Slide 12: Threshold – Primary Voltage Deviation

    Threshold – Primary Voltage Deviation Description: Feeder voltage at any location not to change by more than a specified amount for aggregate DER tripping Value: 5% Basis: IEEE 1453-2015 and Xcel Energy Whitepaper* *Applying IEEE 1453-2015 for Determining the Voltage Deviation Limits for Medium Volt

13. Slide 13: Threshold – Regulator Voltage Deviation

    Threshold – Regulator Voltage Deviation Description: Voltage observed at any regulating device not to change by more than a specified amount of the regulating devices bandwidth Value: 50% of the regulator bandwidth Basis: Moderate value – internally chosen 13 © 2020 Xcel Energy

14. Slide 14: Threshold – Thermal for DER Output

    Threshold – Thermal for DER Output Description: Power flow through any element not to exceed a percentage of the elements normal rating Value: 100% Basis: Not to exceed normal equipment ratings 14 © 2020 Xcel Energy

15. Slide 15: Threshold – Additional Element Fault Current

    Threshold – Additional Element Fault Current Description: Feeder fault current not to increase by more than a percentage of fault current prior to generation Value: 10% Basis: Reliable coordination & protective device interrupt rating 15 © 2020 Xcel Energy

16. Slide 16: Threshold – Breaker Relay Reduction of Reach

    Threshold – Breaker Relay Reduction of Reach Description: Breaker fault current not to decrease by more than a percentage of fault current prior to generation Value: 10% Basis: Guaranteed Fault Detection 16 © 2020 Xcel Energy

17. Slide 17: Threshold – Unintentional Islanding

    Threshold – Unintentional Islanding Description: Power flow through specified elements not to be reduced by more than a percentage of minimum load power flow Value: 100% at feeder breaker and reclosers – meaning total generation equals Daytime Minimum Load – moving to 80% (generation/load) in 2020 a

18. Slide 18: Advanced Settings

    Advanced Settings • Maximum Tap Regulators in Over/Under-Voltage Analysis - Enabled • Maximum DER Penetration = 10MW • Minimum Penetration Increment for Analysis = 100kW • Fault Current Magnitude = 1.2 PU • No advanced inverter functionality enabled at this time 18 © 2020 Xcel Energy

19. Slide 19: Feedback and Questions, Next Steps

    Feedback and Questions -- Next Steps 19 © 2020 Xcel Energy 19

20. Slide 20: Min and Max Hosting Capacity – Explained

    Min and Max Hosting Capacity – Explained • Minimum Hosting Capacity – The Maximum Amount of DER that can be accommodated anywhere on the feeder • Maximum Hosting Capacity – The Maximum Amount of DER that can be accommodated at one point on the feeder 20 © 2020 Xcel Energy

21. Slide 21: Threshold – Reverse Power Flow

    Threshold – Reverse Power Flow As last used in the 2019 HCA Description: Any reverse power flow through specified elements Value: 100% at Breaker - disabled Basis: To highlight where reverse flow is occurring 21 © 2020 Xcel Energy

22. Slide 22: DRIVE Thresholds

    DRIVE Thresholds • Primary Over-Voltage • Primary Under-Voltage • Primary Voltage Deviation • Regulator Voltage Deviation • Thermal for Load • Thermal for Gen • Reverse Power Flow* • Additional Element Fault Current • Breaker Relay Reduction of Reach • Sympathetic Breaker Relay Tripping • Unintentio

Xcel Energy — Technical Presentation (June 2020) on 6ix