NorthWestern Energy Group, Inc. · NASDAQ:NWE

NorthWestern Energy — Technical Presentation (May 2017)

12 slides from NorthWestern Energy's technical presentation, May 11, 2017

  1. Slide 1: RBC Background

    RBC • Background – Bal-001-2 Real Power Balancing Control Performance became effective 7/1/16 • CPS2 was replaced with RBC – NorthWestern participated in a Field Trial from March 7 to June 30. This gave us the opportunity to control to RBC (rather than CPS2) without penalties for violating the stand

  2. Slide 2: CPS2 and RBC

    CPS2 and RBC • Key differences between CPS2 and RBC – CPS2 limits are constant, regardless of the frequency in the interconnection – RBC limits vary based on frequency – CPS2 requires being within the limits in 90% of the 10-minute periods in a month. – RBC requires moving back within the limits in

  3. Slide 3: CPS1 and CPS2

    C CPS1 and CPS2 NorthWesternt Energy 3 Delivering © Bright Future

  4. Slide 4: CPS1 and CPS2

    C CPS1 and CPS2 NorthWesternt De Energy 4 trvering © Bright Futore

  5. Slide 5: CPS1 and CPS2

    C CPS1 and CPS2 NorthWesternt Energy 5 Delivering © Bright Future

  6. Slide 6: CPS1 and CPS2

    C CPS1 and CPS2 NorthWesternt De Energy 6 trvering © Bright Futore

  7. Slide 7: BAA Limits Vary with Frequency

    BAA Limits Vary with Frequency 7

  8. Slide 8: Examples

    BEES SES eZ'ES BEES STRESS ET‘ES OTE L£0ES POES TOES BS'2e SS:2e eS 6b ze Ob ce Erce OF Ze £EsZS PE‘ZeS TE'2e BETS S@ze f2'2S 6E:ze ST ce ET‘ce OT:ze £0:22 POeS TOE 8ST SS'Té eS te 6b TS ob TS Erte OF TS £E'TS PE‘TS TE'Te BAAL Hi BAAL Lo amg ACE 200.0 150.0 100.0 50.0 0.0 50.0 100.0 150.0 -200.0 Del

  9. Slide 9: Examples

    250 200 150 100 50 -100 -150 === DGGS Sched wmegee ACE 21:31 21:34 21:37 21:40 21:43 21:46 21:49 21:52 21:55 21:58 22:01 22:04 22:07 DGGS (NWDS Share) 22:10 ——= Total Wind «seee+ Total Wind Sched oe Basin Creek eeeeee Basin Cr. Sched 22:13 22:16 22:19 22:22 22:3 22:28 22:31 22:34 22:37 22:40 22:43 2

  10. Slide 10: RBC INC and DEC Dispatches

    Cr RBC INC and DEC Dispatches March ‘16 through February '17 Dispatch Instances Number Max Qty. INC 57 122 DEC 73 166 Total 130 NorthWesternt Energy 10 Delivering 6 Bright Future

  11. Slide 11: Current Flexible Capacity Need

    Current Flexible Capacity Need Flexible Capacity Need vs. Resources 350 Colstrip 4, 24 300 Regulation, 50 Hydro, 45 250 Contingency Reserves, 65 Basin Creek, 52 200 MW 150 Within-hour INC, 150 DGGS, 150 100 50 0 Intra-hour Need Flexible Capacity Within-hour INC Contingency Reserves Regulation DGGS B

  12. Slide 12: Near Future Flexible Capacity Need

    Near Future Flexible Capacity Need Flexible Capacity Need vs. Resources Additional INC, 75 Additional Contingency 350 Reserves, 6 Colstrip 4, 24 300 Regulation, 50 250 Hydro, 45 Contingency Reserves, 65 Basin Creek, 52 200 150 MW 100 Within-hour INC, 150 DGGS, 150 50 0 Intra-hour Need Flexible Capac

NorthWestern Energy Group — Technical Presentation (May 2017) on 6ix