Turbine Inlet Cooling: An Energy Solution That s Good for the Environment, Rate Payers and Plant Owners

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1 Turbine Inlet Cooling: An Energy Solution That s Good for the Environment, Rate Payers and Plant Owners Dharam V. Punwani Turbine Inlet Cooling Association Presented at POWER-GEN International Orlando, FL December 2,

2 High Summer Temperatures Lead to High Air Conditioning Loads that Become Major Contributors to the Peak Power Demand Source: Scot Duncan Presentation at ASHRAE June

3 Power Demand and Electric Energy Price Rise with Hot Weather! Price of electric energy for the ratepayers goes up during the peak demand period: as much as 4 times the value during the off-peak period 3

4 Just When High Summer Temperatures Lead to High Air-Conditioning Loads and Power Demand, Combustion Turbine Output Decreases Peak Power Demand Ambient Temperature Scale = 77 to 122 F (25 to 50 C) Daily Generation Profile GT Output Scale = 75% to 100% Lowest Generation Capacity 4

5 Reduced Summer Capacities of Combustion Turbine Power Plants is Well Recognized by the Energy Organizations Fuel Winter Capacity, MW Summer Capacity, MW Lost Summer Capacity, % of Winter Capacity Coal 315, ,380 1 Petroleum 61,171 58,548 9 Natural Gas 412, ,061 9 Source: U.S. Department of Energy s Energy Information Agency 2005 Database 5

6 During Peak Power Demand Period Even Inefficient Peakers also Have to be Operated to Meet the Power Demand Resource [MW] 52,000 50,000 48,000 46,000 44,000 42,000 40,000 38,000 36,000 34,000 32,000 30,000 28,000 26,000 24,000 22,000 20,000 18,000 16,000 14,000 12,000 10,000 8,000 6,000 4,000 2, ESTIMATED PEAK DAY RESOURCE SUMMARY Inefficient Peaker Wind Peaker Generation Hydro Wind Import Thermal Efficient Base Load QF Nuclear Time [Hours] Nuclear QF Thermal Import Wind Hydro Peaker Source: Scot Duncan Presentation at ASHRAE June

7 On a Typical Summer Day in California, Operation of Inefficient Power Plants During Peak Period Doubles the Carbon Dioxide Emissions (lbs/kwh) Compared to Those During Off-Peak Period Y-Axis Unit: CO 2 Emissions, Lbs/kWh 12:00 AM 2:00 AM 4:00 AM 6:00 AM 8:00 AM 10:00 AM 12:00 PM 2:00 PM 4:00 PM 6:00 PM 8:00 PM 10:00 PM Source: Scot Duncan Presentation at ASHRAE June 2007 SCE PG&E SDG&E 7

8 Carbon Dioxide (GHG) Emissions of Fossil Fuel Power Plants! Power plants that burn fossil fuels (coal, oil, natural gas or synthetic gases) are significant producers of carbon dioxide and other emissions! There are two types of fossil fuel power plants: 1. Burn fuel to produce steam and use steam in steam turbines to produce electric power 2. Burn oil or gas directly in combustion turbines (CTs) to produce power! Power plants that burn coal produce the most emissions (lbs/mwh)! Power plants that use natural gas in CTs produce the least emissions (lbs/mwh) 8

9 Natural Gas-Fired CTs in Combined- Cycle Systems have the Lowest Heat Rates and Least Emissions System Combined-Cycle CT Simple-Cycle CT Steam Turbine Heat Rate (LHV) Range, Btu/kWh 6,500 7,000 8,000 10,000 12,000 15,000 Fuel Natural Gas Natural Gas No. 6 Fuel Oil CO 2 Emissions, lbs/mwh 814 1,250 2,236 NO x Emissions, lbs/mwh SO x Emissions, lbs/mwh Source: Pasteris Energy, Inc. 9

10 Power Plant Operation Priority for Reducing Emissions The preferred order of operating fossil power plants using natural gas should be: 1. CT in combined-cycle system (Lowest Heat Rate i.e. Highest Energy Efficiency) 2. CT in simple-cycle system 3. Steam turbine system (Highest Heat Rate i.e. Lowest Energy Efficiency) 10

11 Two Unfortunate and Unfavorable Characteristics of Combustion Turbine Power Plants! During hot weather, just when power demand peaks, 1. Power output decreases significantly " Up to 35% below rated capacity " Depends on the CT characteristics 2. Fuel consumption (heat rate) and emissions increase per kwh 11

12 CT Power Plants Generation Capacity Decreases with Increase in Ambient Temperature and Depends on the CT Design 105% EFFECTS OF COMPRESSOR INLET AIR TEMPERATURE ON GAS TURBINE POWER OUTPUT PERIOD OF GREATEST DEMAND % OF RATED POWER 100% 95% 90% 85% 80% ISO DESIGN POINT NEW AERO-DERIVATIVE POWER OUTPUT Compression Ratio = 30 OLD "FRAME" POWER OUTPUT Compression Ratio = COMPRESSOR INLET AIR TEMPERATURE, degrees F Up to 19% capacity loss at peak demand for this CT 12

13 CT Power Plants Energy Efficiency Decreases (i.e. Heat Rate Increases) with Increase in Ambient Temperature Heat Rate, Percent of Design Aeroderivative 103 Frame Ambient Dry-Bulb Temperature, F Fuel Use Increase (i.e. Energy Efficiency loss) at peak demand Note: Heat rate is directly proportional to fuel consumption per kwh and inversely proportional to energy efficiency 13

14 Turbine Inlet Cooling (TIC) Overcomes the Effect of Hot Weather on the CT Capacity De-rating Net CT Power Output,% of Design No Cooling W ith TIC Rated Capacity Rated Capacity With Cooling No Cooling Ambient Dry-Bulb Temperature, F 14

15 Preferred Dispatch Order for a Typical Combined-Cycle System with TIC 73,394 8,440 Btu / kwh Supplementary Duct Firing 6,799 Btu / kwh Cooling to Dew Point 16,874 7,894 Btu / kwh Cooling to 50 F 452,183 6,371 Btu / kwh Base Case Dispatch Order at 95 F Basis: GTPro model at 95F DB/78F WB with inlet chilled 207FA. Source: TAS 15

16 Turbine Inlet Cooling (TIC) Reduces Need for New Power Plants! Implementing TIC on combustion turbines in combined-cycle (CC) systems effectively displaces/reduces operations of combustion turbines in simple-cycle (SC) systems! TIC for each nominal 500 MW CC plant eliminates the need for a nominal MW SC peaker and its associated siting, emissions, interconnection and other issues 16

17 Turbine Inlet Cooling Provides Environmental Benefits! Reduces the need for operating inefficient and higher-emission power plants and thus, # Reduces emissions of pollutants (SOx, NOx, particulates) # Reduces emissions of green house gas (CO 2 ) 17

18 Turbine Inlet Cooling (TIC) Reduces CO 2 Emissions Environmental Impact pounds of CO2 per MWH 1,200 1,000 pounds per MWH , Virtual TIC Peaker New Aero Peaker Basis: LM6000PC-Sprint with hot SCR & TIC vs. incremental MWH from combined cycle 207FA with TIC added Source: TAS 18

19 Turbine Inlet Cooling (TIC) Reduces Emissions of Regulated Pollutants 0.5 Environmental Impact Regulated Pollutants 0.4 CC NOx SCR = 3 ppm SC NOx SCR = 3 ppm lbs per MWH Virtual TIC Peaker 0.10 New Aero Peaker HC CO NOx TIC Reduces Total Emissions (lbs/mwh) by Over 50% Basis: Total of all pollutants (lbs/mwh), LM6000PC- Sprint with hot SCR & TIC vs. incremental MWH from combined cycle 207FA with TIC added (Source: TAS) 19

20 Turbine Inlet Cooling (TIC) Technologies are Simple and Proven! TIC is simple Ambient Air To Turbine # Cool the ambient air before it enters the turbine # Just as we cool the air entering buildings! TIC technologies are proven # Thousands of plants already benefit from TIC # TICA Web site database of 100+ plants worldwide 20

21 Many Turbine Inlet Cooling System Options are Available! Evaporative Systems: Wetted Media or Fogging! Chiller Systems: Mechanical or Absorption Chillers! Chillers with Thermal Energy Storage! LNG Vaporization System! Wet Compression System * Application Limited to only where Liquefied Natural Gas (LNG) is Available 21

22 Factors Affecting the Capacity Enhancement Potential of TIC! TIC Technology Selected! CT Design and Characteristics! Weather Data (dry-bulb and coincident wet-bulb temperatures) for the Geographic Location of the CT! Selected ambient design conditions! Selected (if allowed by the TIC technology) cooled air temperature! TIC Parasitic Load! Pressure drop across the component inserted upstream of the compressor (insertion loss) 22

23 Examples of the Effect of TIC Technology and Ambient Temperature on Capacity Enhancement Net Output Enhancement, MW F DB and 80F WB 95F DB and 60F WB Wetted Media Fogging Electric Chiller Wet Compression Combined-Cycle System: Two 501FD1 and one ST Sources: Wet Compression: Caldwell Energy, Inc. All Others : D.V. Punwani Presentation, Electric Power

24 An Example of the Monthly Incremental Electric Energy Provided by Some of the TIC Technologies (316 MW Cogeneration Plant Near Houston, TX) Evaporative Cooling is a Wetted Media system Single-Effect and Double-Effect Refer to Absorption Chillers Source: D.V. Punwani et. al. Presented at ASHARE

25 Factors Affecting the Economics of TIC Technology! Market Value of Increased Electric Energy Produced or the Avoided Cost of Buying the Same Energy from the Market! Market Power Demand Profile for Selling Electric Power or Power Demand Profile for the Power User! Market Value of Increased Plant Capacity! Cost of Fuel! Cost of Water 25

26 Example of TIC Providing Capacity Enhancement at Lower Capital Costs (316 MW Cogeneration Plant Near Houston, TX) Capacity Enhancement Capital Cost, $/MW 1,000, , , , , ,941 15,660 14,797 95,215 No Cooling Wetted Media Fogging Wet Compression 183,421 Electric Chiller Sources Wet Compression: Caldwell Energy Other: 26

27 TIC Provides Additional Electric Energy at Lower Operating Costs $150 $140 $130 $120 $110 $100 off-peak power to recharge TES $40 per MWH amortized over peak hours variable O&M $6 per MWH $6.00 Annualized Cost Of Electricity New Aero Peaker = $115 Virtual TIC Peaker = $ 65 $ per MWH $90 $80 $70 $60 $50 $40 $30 $20 $10 $0 $12.63 $1.94 $46.28 $- Virtual Peaker $4.43 gas = $8 per mmbtu MM Btu LTSA = $20 per ton $111, year capital recovery no interest charges $33.58 $6.29 $68.69 fixed O&M $250,000 Aero Peaker Water Cost Off-Peak Power Variable O&M Fuel Cost Fixed O&M Capital Recovery Basis: LM6000PC-Sprint with hot SCR & TIC vs. incremental MWH from combined cycle 207FA with TIC added. (Source: TAS) 27

28 Turbine Inlet Cooling Provides Not Only Environmental but also Economic Benefits # Generates more MWh and revenue during peak demand periods when electric energy value and price are highest # Reduces capital cost per unit of the increased generation capacity compared to new power plants # Reduces cost of electric energy generation compared to the low energy efficiency peakers # Reduces cost for ratepayers by allowing lower capacity payments by the independent system operators (ISOs) to power producers 28

29 Suggested Changes To Regulatory Structure Notes:! Utilize full potential of existing combustion turbines plants # Require addition of TIC before allowing new plants to be built! Exempt TIC from environmental re-permitting # Use of TIC helps displace/eliminate operation of higher emission power plants! Calculate capacity payments for plant owners on the basis of systems incorporating TIC # Consistent with the PJM affidavit made to the FERC in August 2005 PJM: PJM Interconnection, LLC FERC: Federal Energy Regulatory Commission 29

30 Conclusions! Turbine inlet cooling can provide significant increased generation capacity during hot weather from energy efficient combined-cycle (CC) and simple-cycle (SC) power plants! More MWh from CC and SC plants minimizes/eliminates operation of higher-emission producing thermal power plants/steam-turbine systems! Turbine inlet cooling (TIC) of CC and SC power plants also reduces the cost of generation compared to combustion turbine without TIC and thermal power plants! In summary, TIC is an energy solution that is good for the environment, for ratepayers, and for plant owners 30

31 TICA Announcement Annual Meeting of TICA Members! Today (December 2; Tuesday) 4-6 PM! Room S310F in the Orange County Convention Center! Guests are Welcome to Attend 31