Barry Ingold Senior Vice President, Generation

Tri-State Generation and Transmission Association, Inc. Not-for-profit cooperative wholesale power supplier owned by member cooperatives and public power districts Serve more than1 million member- owners across nearly 200,000 square miles

Tri-State G&T 2,753 MW coincident peak demand 17.8 GWh sales $1.4 billion operating revenue $53.4 million margins $4.9 billion assets 1,561 employees

Generation Resources 1,874 MW base load coal 965 MW intermediate and peaking natural gas/oil 923 MW renewable Hydro Wind Solar 558 MW contracts

2016 Tri-State Resource Mix 2016 Energy As a % of gross member sales 2016 Capacity (%) Oil <1% Market Purchases 12% Renewable 24% Coal 43% Coal 50% Renewable 27% Basin 12% Natural Gas 19% Basin 9% Natural Gas 2% Oil 2%

Renewable Generation April 2017 RENEWABLES = 379 GWH Other Renewables 1% Policy 115 5% RENEWABLES = 379 GWH 26% of Total Power Supply 32% of Member Sales San Isabel 1% Alta Luna 2% Basin 9% Carousel 17% WAPA - LAP 19% Colorado Highlands 9% Kit Carson 5% WAPA - CRSP 33% Cimarron 1%

Scheduled Coal Unit Retirements Total Capacity (MW) Tri-State Capacity (MW) Retirement Date San Juan #3 Waterflow, NM 500 41 2017 Nucla Nucla, CO 100 2022 Craig #1 Craig, CO 428 104 2025 TOTALS 1,028 244

Resource Additions 1 R T 8 Resource Additions Year Resource Fuel Megawatts 2008 Rawhide Natural Gas 100 2009 J. M. Shafer 150 Brush 70 2010 Kit Carson Wind 51 2011 Cimarron Solar 30 122 2012 Basin Electric Unspecified 75 1 R T Colorado Highlands 67 2013 Boulder Canyon Hydro 5 CHW 2 24 2014 Ridgway 8 Vallecito 6 2015 Shoshone 3 2016 Carousel San Isabel Solar 2017 Williams Fork 3.5 Alta Luna 25 Twin Buttes 76 2008-present Member Generation Various 113 * 8 Resource Additions enewables: Natural gas: Unspecified: 592 MW 442 MW 75 MW otal 1,109 MW * Tri-State provided financial incentives

Rankine and Advanced Steam Cycles

The Rankine Cycle

Subcritical steam production

Supercritical steam production

Continued Efficiency Gains Comparison Ultra Supercritical 1960 Vintage Subcritical Reheat Supercritical Temperature Early 20th Century Vintage Subcritical Non-Reheat 1940 Vintage Subcritical Non-Reheat Entropy

Combustion Turbine Technology

Combustion Turbine Technology

Combustion Turbine Cross- section

Combustion Turbine Technology Combustion Turbine Technical Specifications GE LM6000 GE 7E.03 GE 7F.06 GE 7HA.01 MHPS M501J Net Output (MW) 45-58 91 270 280 327 Net Heat Rate (Btu/Kwh) 8619 10060 8250 8180 8322 Thermal Efficiency 39.6 33.9 41.4 41.7 41 Exhaust Temperature - Degrees C 455 552 593 626 636 Ramp Rate (MW/min) 50 40 Plant Turndown % 25 35 30

Combined Cycle Combustion Turbine Technology

Combined Cycle Combustion Turbine (CCCT)

Combined Cycle Thermal Efficiency  LM6000 SC 39.6% CC 51.9%  501J 41.0% 61.5%

Combined Cycle Thermal Efficiency

Allam Cycle

Allam Cycle To CO2 customer

How Does it Work? Very hot water 2.75% Hot water 2.75% Oxygen 4.75% of mass Cool water 2.75% Pipeline ready CO2 3.25% Clean water 2.75%

Integrated Gas Combined Cycle (IGCC) Technology

Integrated Gas Combined Cycle

Kemper County IGCC 27

Reciprocating Internal Combustion Engines (RICE)

Wärtsilä 18V50SG

New Technology – Turbine Hall

Reciprocating Engines

Nuclear

B&W mPower Design

NuScale SMR Technology NuScale design has achieved the “Triple Crown” for nuclear plant safety. The plant can safely shut-down and self-cool, indefinitely, with: No Operator Action No AC or DC Power No Additional Water

NuScale Design 12 X 50MWe Compact 46-acre site Separated Nuclear and Turbine Islands All safety-related systems underground One-to-one reactor to T/G alignment Optimized for minimum staff and O&M Water- or air-cooled condenser Conventional steam cycle components

NuScale Design

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