US Army Corps of Engineers BUILDING STRONG ® Power Plant Uprate Brief Missouri River Mainstem Mid-West Board Meeting Gary Hinkle Omaha District June 2015

BUILDING STRONG ® 2 Missouri River Mainstem Projects 2

BUILDING STRONG ® 3 Fort Peck Dam/Fort Peck Lake

BUILDING STRONG ® 4  5 Units (185.2MW); On-Line  Completed Power Train Improvements Unit 1 & 3 Rewinds Unit 2 Rehab (In-Progress)  Power Train Limitations / Improvements Plant 1 - Penstock Limited  Turbines Designed in 1930’s  Fort Peck Unit 3 Turbine Modifications Plant 2 – Unit 4&5 / Generator Limited  Original Windings 40MW / New Windings Possibly 50MW  Turbine Efficiency ? Fort Peck

BUILDING STRONG ® 5 Garrison Dam/Lake Sakakawea

BUILDING STRONG ® 6  5 Units (583.3MW); On-Line  Major Rehab  Generators, Turbines, Auxiliaries Rehabbed  Plant Rating Increase of 88.8MW  Efficiency Increase of 8%  Reduced Cavitation Maintenance  (Benefits of Modern Design & Materials (Stainless Steel) Garrison

BUILDING STRONG ® 7 Oahe Dam/Lake Oahe

BUILDING STRONG ® 8  7 Units (786MW); On-Line  Completed Power Train Improvements Unit Rewinds (112.3MW) Unit Breakers/ Exciters/ Governors  Power Train Limitations / Improvements Turbine Limited  Rated Head (128,500HP – 95.8MW) Max Head (151,000HP – 112MW)  Turbine Efficiency Improvements: Best Gate; Full Gate  Turbine Capacity Improvements: 5% Equipment Nearing End of Service Life:  Generator Windings (32 yrs)  Transformers / Turbines / Rotors / BOP: Original - 53 yrs Oahe

BUILDING STRONG ® 9 Big Bend Dam/Lake Sharpe

BUILDING STRONG ® 10  8 Units (538MW); On-Line  Completed Power Train Improvements Unit Rewinds (Units 1-3) (Units 4-8) Unit Breakers / Exciters / Governors  Power Train Limitations / Improvements Turbine Limited  Fixed Blade Kaplan Turbine  Max Tailrace Elev 1320’; Yet Tailrace Elev 60% of the Time; (Limits Output MW) Equipment Issues  Early History of Severe Blade Cracking Near Blade Root (resolved)  Recent Increase in Cavitation / Heavy Corrosion  Transformers / Turbines / BOP: Original - 51 yrs Big Bend

BUILDING STRONG ® 11 Fort Randall Dam/Lake Francis Case

BUILDING STRONG ® 12  8 Units (320MW); On-Line  368MW - 46MW/Unit 115% Rating  Completed Power Train Improvements Unit Breakers/ Exciters/ Power Cables  Power Train Limitations / Improvements Turbine Limited  Units Operate Off Peak (Peak Efficiency 50% Gate)  Efficiency Improvements of 6-12% Possible  Capacity Increase to 53MW Possible Equipment Issues  Generator Winding 61Yrs Old  Transformers / Turbines / BOP: Original - 61 yrs Fort Randall

BUILDING STRONG ® Fort Randall Operation

BUILDING STRONG ® Estimated Efficiency Improvements of Fort Randall Unit Rehab

BUILDING STRONG ® Gavins Point Dam/Lewis and Clark Lake 15

BUILDING STRONG ® 16  3 Units (132MW / 44MW ea); On-Line  Completed Power Train Improvements Unit Breakers/ Exciters/ GSU Transformers/ Governors  Power Train Limitations / Improvements Turbine Limited  54,000hp rated head)  Turbine Efficiency Improvements: Best Gate; Full Gate  Capacity Increase to 50.5MW Possible w/o Generator Replacement Equipment Issues  Stator Core Egg Shaped  Last Rewinds 1987  Turbines Cavitation, Corrosion, Cracking Concerns  BOP: Original - 59 yrs Gavins Point

BUILDING STRONG ® 17 Questions ?