Lancaster “Project” Tracy Rolstad Avista Transmission System Planning

Lancaster Request Avista has requested BPA evaluate two options (Lines and Loads Request) Alt A: Loop into Boulder—Rathdrum 230 kV Alt B: Loop into Beacon—Rathdrum 230 kV

Lancaster Loop In Five Alternatives Studied by Avista Status Quo Alt A: Loop into Boulder—Rathdrum 230 kV Alt B: Loop into Beacon—Rathdrum 230 kV Alt C: Noxon—Lancaster 230 kV into Rathdrum Alt D: 230 kV trunk line from Rathdrum

Basic One Line Western MT Hydro Cabinet Gorge 500 kV to Grand Coulee And Montana Libby Lancaster Bell Hot Springs Noxon Rathdrum Boulder Beacon

Lancaster-Noxon 230 kV Bell-Lancaster 230 kV Beacon-Rathdrum 230 kV Bell-Taft 500 kV Boulder-Rathdrum 230 kV

Bell-Taft 500 kV Lancaster-Noxon 230 kV Cabinet-Rathdrum 230 kV Beacon-Rathdrum 230 kV Boulder-Rathdrum 230 kV

Superior Option Alternative A Bring Lancaster into Boulder—Rathdrum 230 kV line “Intercepts” westbound energy before it travels east through the Bell—Beacon complex Increases use of Boulder and Rathdrum stations Decrease use of Beacon and Bell stations Losses are reduced equally for AVA and BPA Perhaps as much as 2 to 3 MW always Technically a “win” for both parties

Parameter Status Quo Alt A Alt B Alt C Alt D Total System Losses 6395.11 MW 6387.74 MW 6388.40 MW 6388.24 MW 6388.79 MW NW Area Losses 1270.71 MW 1263.43 MW 1263.96 MW 1263.78 MW 1264.32 MW AVA Owner Losses (MW) 76.71 MW 72.46 MW 72.76 MW 72.40 MW 72.85 MW AVA Owner Losses (MVAr)  494.22 MVAr  462.12 MVAr  465.07 MVAr  461.01 MVAr  464.47 MVAr Bell 500/230 kV 128.21 MW 134.02 MW 131.17 MW 130.69 MW 133.53 MW Bell 230/115 kV 236.32 MW 218.25 MW 220.24 MW 220.40 MW 221.20 MW Beacon 230/115 kV #1 215.07 MW 214.13 MW 218.62 MW 216.46 MW 216.08 MW Beacon 230/115 kV #2 202.34 MW 200.99 MW 202.77 MW 202.05 MW 201.78 MW Boulder 230/115 kV #1 113.05 MW 132.87 MW 127.18 MW 129.04 MW 127.97 MW Boulder 230/115 kV #2 106.85 MW 124.95 MW 120.57 MW 121.26 MW 121.33 MW Rathdrum 230/115 kV #1 70.32 MW 77.64 MW 77.28 MW 78.09 MW 77.46 MW Rathdrum 230/115 kV #2 90.80 MW 100.97 MW 100.48 MW 101.60 MW 100.73 MW   Beacon-Bell #4 230 kV -286.08 MW -184.47 MW -190.29 MW -192.63 MW -198.29 MW Beacon-Bell #5 230 kV -277.73 MW -167.29 MW -165.02 MW -172.06 MW -178.39 MW Beacon-Boulder 230 kV 157.84 MW 60.88 MW 89.78 MW 79.82 MW 84.69 MW Beacon-Rathdrum #2 230 kV -11.43 MW -124.23 MW N/A -133.63 MW -125.87 MW Boulder-Rathdrum 230 kV -142.73 MW -266.79 MW -281.53 MW -272.57 MW Boulder-Lancaster 230 kV -312.17 MW Lancaster-Rathdrum 230 kV 37.27 MW Beacon-Lancaster 230 kV -155.86 MW 178.93 MW Beacon throughflow (MW) 629.46 MW 515.70 MW 548.96 MW 537.62 MW 542.35 MW Bell throughflow (MW) 1146.50 MW 894.37 MW 902.65 MW 912.05 MW 925.54 MW Boulder throughflow (MW) 300.35 MW 372.72 MW 356.92 MW 361.78 MW 357.64 MW Lancaster throughflow (MW) 372.50 MW 449.87 MW 446.54 MW 249.78 MW 442.38 MW Rathdrum throughflow (MW) 350.41 MW 320.46 MW 464.00 MW 613.06 MW 596.15 MW

Disclaimers Actually study is performed by BPA BPA results are presumably definitive BPA study is not yet complete Station expansion will be required Implies all associated issues such as property acquisition, environmental issues, outages, etc