11 Febrauary 2002
TECHNOLOGY FOR GAS TURBINE POWER PLANTS - AN ENVIRONMENTAL VIEW
Olav Bolland
Associate Professor Norwegian University of Science and Technology (NTNU)
IBC Conference New Dynamics of Scandinavian Gas & Power Oslo, 11-12 February 2002
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Gas turbine market forecast - 1 number of gas turbines 2001-2010
800 700
Number of gas turbines
600 500
125+ MW 20-50 MW
400 3-10 MW 300
Number of gas turbines size [MW] Total 2001-2010 125+ MW 5155 20-50 MW 4377 50-125 MW 4182 3-10 MW 3280 0.2-3 MW 1563 10-20 MW 326 total 18883
50-125 MW
200 0.2-3 MW
10-20 MW 0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
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0.2-3 MW 3-10 MW
100
10-20 MW 20-50 MW 50-125 MW 125+ MW
Source: 2001/2002 TMI Handbook
Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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11 Febrauary 2002
Gas turbine market forecast - 2 Value of gas turbines 2001-2010
25000 125+ MW
Value (U.S. $ millions)
20000 0.2-3 MW 3-10 MW
15000
10-20 MW 20-50 MW 50-125 MW 10000
125+ MW 50-125 MW
Value of gas turbines U.S. $ millions (2001) size [MW] Total 2001-2010 125+ MW 201825 50-125 MW 98608 20-50 MW 53600 3-10 MW 7019 10-20 MW 1840 0.2-3 MW 1600 total 364492
20-50 MW
5000
0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
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Source: 2001/2002 TMI Handbook
Gas turbine market forecast - 3 By manufacturer 2001-2010
by value of power generation gas turbines
by numbers of power generation gas turbines
Kawasaki 1%
others 18 %
Pratt & Whitney 2%
Kawasaki 5%
GE 42 %
Pratt & Whitney 5%
others 18 %
Solar 1% Rolls-Royce 1%
GE 55 %
Siemens 14 %
Solar 5% Rolls-Royce 7% Siemens 7%
Alstom 11 %
Alstom 8%
Others: 12 firms, including Ansaldo, Fiat, Mitsubishi and Vericor
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Source: 2001/2002 TMI Handbook
Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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11 Febrauary 2002
General trends for gas turbines - 1 • Manufacturing – Excess production capacity – OEMs increase standardization
• High demand for gas turbines, but prices remain fairly constant over time 700
Cost per kW (US$)
600 500 400 300 200 100 0 1-2 MW
5 MW
50 MW
150 MW
250 MW
260-340 MW
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General trends for gas turbines - 2 • Manufacturers have become more selective to new projects • Outsourcing of EPC • A tendency to promise less on guarantees for power output and efficiency • Gas turbines have become more difficult to insure • Microturbines (38% efficiency • Large Combined Cycles ≈ 58-60% efficiency • Gas turbines 40-50 MW ≈ 42-45% efficiency
Definitions of Turbine Inlet Temperature - TIT T1
T2
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T1: Combustor exit temperature (not much used) T2: Temperature after first blade row in Stage 1 (mostly used) T3: Calculated mixing temperature of combustor exit stream and cooling air (ISO definition)
Bolland
Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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11 Febrauary 2002
Historical Development of: Turbine Inlet Temperature
Max. Metal Temperatures
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Air and steam cooling of turbine blades
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Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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11 Febrauary 2002
Turbine blade materials
Directionally Solifified
Singlecrystal
Normal casting
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Gas Turbine Power Plant Efficiencies – Potential 2010
GT + SOFC
Aeroderivative GT Combined Cycle Humid Air Turbine
60
Combined Cycle
GT + ABC
Thermal Efficiency [%]
50
Aeroderivative Intercooled GT
40
Heavy Duty GT
Aeroderivative GT
30
Intercooled Recuperated GT
20 10 0 0
30
60
90
120
150
180
210
240
270
300
GT Power Output [MW] 12 Bolland
Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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11 Febrauary 2002
NOX emissions from gas turbines - 1 • NOX ≡ NO and NO2 • causes acid rain and ground level ozone formation • Quantified as ppmv = parts per million on volumetric basis • Emission limits in USA more stringent than in Europe • 9 ppmv vs. 25 ppmv • technology development for 50 Hz (Europe) machines is lagging behind the 60 Hz (USA) • But: In Norway ≈ 5 ppmv
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Reducing NOX emissions from gas turbines - 2 commercially available technologies
• Dry Low-NOX Combustion
• Lean pre-mix of fuel and combustion air • Offered for most Gas Turbines on natural gas • 9-25 ppmv achievable on gaseous fuel, operating experience: 9-12 ppmv • Is becoming available also for liquid fuels
• Water (liquid or steam) Injection into the GT combustor • Water/fuel-ratio 1-1.6 • Below 25 ppmv (natural gas) or 42 ppmv (dist. oil)
• Selective Catalytic Reduction (SCR) • • • • • •
Use of NH3 to react with NO2 (to N2 and H2O) Catalyst at appr. 350 °C in the steam boiler Typically used in oil fired units Below 10 ppmv achievable (typical 80% reduction) Ammonia slip → ammonium sulfate & ammonium nitrate State-of-the-art: 3 ppmv NOX & 3 ppmv NH3
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Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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11 Febrauary 2002
Reducing NOX emissions from gas turbines - 3 new technologies
• Catalytic Combustion • • • • •
Catalyst in the combustor Tests carried out in a small Gas Turbine not commercially available Temperature limitation, life-time limited 3 ppmv demonstrated in test, single-digit emissions achievable
• Catalytic absorption (SCONOX)
• Catalyst the exhaust gas system (150-370 C) • Use of a solid dry catalyst, Potassium Carbonate, to reduce NO2 (to N2 and H2O) • The catalyst is first converted Potassium Nitrites and then regenerated by a CO2/H2-containing gas • Below 3 ppmv NOX achievable
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Options for power plant CO2 capture Exhaust, 0.3-0.5% CO2 1
Power plant Conventional
CO2 capture 2 H 2 + O2 ⇔ 2 H 2O
Coal Oil Natural gas
2
Gasification Reforming
Watershift H 2 + CO
H 2 + CO2 O2
3
Power plant Oxy-fuel combustion CH 4 + O2 ⇔ CO2 + 2 H 2O
CO2 capture
Power plant Hydrogen-rich fuel
CO2 storage
Exhaust, 0.1-0.5% CO2
Air separation Water removal
1: Post-combustion principle 2: Pre-combustion principle 3: Oxy-fuel principle = direct
stoichiometric combustion with oxygen
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Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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11 Febrauary 2002
Costs for natural gas fired CC with CO2 Capture z
z
z
z 17
Total cost for CO2 capture and sequestration in a saline aquifer, based on available technology is 25-60 $/tonne CO2 for power plants of 1200-400 MW (7% pre tax discount rate) There are significant differences between the “post-combustion” vendors: cost, plant configuration and technology ⇒ immature technology Cost reduction potential up to 25% ( 1 million tonnes/year)
Bolland
Economies of scale – exhaust gas CO2 capture from CC Plant cost [US$/kW]
400 MW
2100 post-comb 1800
Larger gradient with CO2 capture 1200 MW post-comb
1500 1200
2.7-3.1
Factor ∼ 2.5
900 600 300 0 200
pipeline & well excluded
No CO2 capture CO2 capture 400
600
800 1000 1200 1400
Plant output [MW]
z
z
CO2 capture increases investment costs by a factor 2.4-3.1 (per kW, pipeline & well excluded) Economies of scale is more predominant for CO2 capture plants compared to CC
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Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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11 Febrauary 2002
Economies of scale – exhaust gas CO2 capture from CC Including operational and investment cost - pipeline & well included ⇒ CO2 capture cost is 25-60 US$/tonne CO2 • Increasing plant size from 400 to 1200 MW, reduces cost per tonne CO2 by 50%
• CO2 pipeline/injection well contribution to the reduction is 60% • CO2 capture and compression contribution is 45% (65-70% of overall cost)
• CO2 pipeline cost depends mainly on length, and to a much lesser extent on diameter • The well comprise only a small fraction of total costs
•Total cost for CO2 capture and sequestration in a saline aquifer, based on available technology is 25-60 $/tonne CO2 for power plants of 1200-400 MW (7% pre tax discount rate) CO2 tax in Norway z Use of natural gas as fuel in oil/gas production ≈ 36 US$/tonne CO2 19 Bolland
Barriers for power generation with CO2-capture – 1 Reducing the cost gap ?
Production cost €/MWh
Conventional Gas Fired Combined Cycle, NGCC
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Gas fired Combined Cycle with CO2 capture
NGCC with CO2 capture
... including sale of CO2 for 12 €/tonn 12-19 €/MWh
4-10 €/MWh added CO2-tax 12 €/tonn CO2
Conventional NGCC
12.5 €/MWh ≈ 100 NOK/MWh = 0.1 NOK/kWh
Bolland
Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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11 Febrauary 2002
Barriers for power generation with CO2-capture – 2 Infrastructure for CO2 does not exist !
For EOR (enhanced oil recovery): Large quantities of CO2 required ≈ 10 mill. tonnes CO2/year
CO2 for enhanced oil recovery
Large quantities required to help influence greenhouse gas emissions
CO2 into aquifers CO2 into gas reservoirs
Distinct scale of economy What should be done: Establishing a physical infrastructure for CO2 International regulations for liability and verification
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Capacity: Norwegian sector: Commercial interfaces ≈ 20 Gt of CO2 (sealed structures) ≈ 20 years of all CO2 produced Source: Holloway et al., 1996: The underground disposal of carbon dioxide. in European power plants Report from a Joule II project
Why hydrogen ? Short term: Improved air quality in large cities Independence of oil Long term: Shortage and high prices for fossil fuels Limitation on the emission of air pollutants Renewable energy O2
Hydropower
Biomass
Electr.
Water electrolysis
H2
H2
Fuel cell
Wind
Solar water 22 Bolland
Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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11 Febrauary 2002
Barriers for the use of hydrogen as an energy carrier – ”hydrogen economy” 1) The technology development for fuel cells is slower than expected Cost has to come down to 50-60 $/kW, ⇒ market has to “lift off”, motor industry has to do the job 2) Technology for storage of hydrogen 3) Infrastructure (transport, distribution, filling stations) 4) Acceptance
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What about fuel cells ?
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Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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11 Febrauary 2002
Hybrid Fuel Cell and Gas Turbine Water
Exhaust
Heat exchanger Hot, pressurised air
Natural gas
SOFC Solid Oxide Fuel Cell
Combustor
Compressor
Turbine
Air
Recuperator Gas Turbine
~
Exhaust Stack Air Inlet
Generator
Power: 250 kW - 10 MW Efficiency: 58-70% fuel-to-electricity
Fuel Processing System SOFC Module Switchgear
SOFC Power Conditioning System
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Courtesy Shell International Exploration and Production BV
Instrumentation and Controls
Thank you !
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Olav Bolland, New Dynamics of Scandinavian Gas & Power, Oslo 2002
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