Technology Adaptation In Power Generation

Transcription

1 Technology Adaptation In Power Generation Evolution of the Gas Turbine Bruce Rising Siemens Energy, Inc. Page 1

2 US Power Generation Today The US power infrastructure is in the process of evolving from one that is substantially based on thermal (Rankine) energy conversion Approximately 500,000 MWe of thermal power 330,000 MWe based on coal We have retired some 70,000 MW of thermal plants since 1970 Over 1,100 units, averaging 44 years of service, and 77 MWe capacity Expect to retire at least this amount in the next few years. 250,000 MWe of combined (Brayton + Rankine) cycle systems 125,000 MWe of Brayton cycle (peaking units) 100,000 MWe of Nuclear (Rankine cycle) units 4 additional units under construction, and some being retired 50,000+ MWe of Wind Expect that the gas turbine (Brayton) cycle will be the mainstay for much of future energy developments Page 2

3 BACKGROUND ON THE DEVELOPMENT Page 3

4 Expansion of the US Power Infrastructure Rankine Era 1970 CAA FGD Retrofit Era Brayton Era NYC Blackout 1977 CAA NE Blackout Global Economic Depression 1990 CAA PUHCA PUHCA Repeal Page 4 PURPA Fuel Use Act

5 Generation by Fuel Type-through 2012 Primarily Rankine cycles Combination of Rankine and Brayton Cycles Page 5

6 67,259 MWe Coal 54,865 MWe Coal 17,791 MWe Coal 200,985 MWe Coal Page 6

7 Page 7

8 TECHNICAL DEVELOPMENTS Page 8

9 Large Frame Gas Turbine (+250 MW) Page 9

10 Evolution in Turbine Design Page 10

11 Component Development Compressor COMPRESSOR CHALLENGES Increased mass flow Increased efficiency requirements Increased pressure ratio Cost Compressor CFD Results COMPRESSOR SOLUTIONS New Compressor design, decreased stages Lower production cost 3-D blading for improved efficiency Highly loaded airfoils Compressor Rear Stage Test Rig Page 11

12 DLN Combustor Eliminate use of water injection for NO x control Reaching lower NO x emission levels than possible with diluents Increased efficiency Increased parts life Page 12

13 Premixed Combustor Design-a 30 year design evolution Premixed combustion system designs are the de facto standard in much of the world. They are primarily optimized to function with natural gas (some smaller industrial units can function with liquid distillate fuels). But natural gas is the default fuel design for the bulk of systems placed into practice. DLN combustors require a narrow range of fuel quality specifications (i.e. quantities of methane, ethane, and propane, in the fuel supply). Nominally, this is controlled by a pipeline tariff. Page 13

14 Combustion System Design Page 14

15 Component Development Turbine TURBINE CHALLENGES TURBINE SOLUTIONS Page 15 High firing temperatures exceed material limits Increased mass flow Multi-fuel capability requirement Physical component size (blade height) Aerodynamics Advanced 2D & 3D CFD Modeling High Turning, Highly Loaded Airfoils End Wall Contouring development Exhaust diffuser development Sealing Technology Heat Transfer Advanced cooling row 1 blade, novel cooling of row 4 blade, advanced film cooling patterns Component Design Manufacturing of novel component concepts Blade root design optimization through software tool development CFD Analysis Advanced Vane

16 Power Turbine-High Temperature Energy Conversion A single vane airfoil Turbine Wheel with all blade airfoils Page 16

17 Heat Transfer-Blade Cooling Page 17

18 Material Evolution on the Steam Cycle Page 18

19 Evolution of Combined Cycle Power Plants / % net efficiency 56% net efficiency > 58% net efficiency > 60% net efficiency Killingholme, 2 x 450 MW Didcot B 1&2, 710 MW MW Mainz-Wiesbaden, > 400 MW Irsching 4 incl. SGT5-8000H, > 530 MW Continuous development of gas turbine and combined cycle technology Page 19

20 Conceptual design looks like this Plume model NOx, CO, NH3, PM2.5 NOx, CO, NH3, PM2.5 Plume drift Steam Turbine Material Stress Material Stress Acoustics/noise Heat transfer materialscorrosion Piping design Acoustics/noise Acoustics/noise Lube systems Gas quality SFC for fast-start T&D-relays, switchgear Grid interconnection Engine controls, diagnostics and monitoring Gas pipeline supply Gas Turbine Page 20

21 It finally looks like this Page 21

22 WHAT ELSE? Page 22

23 and if CO 2 has to be captured The area occupied by the carbon capture and compression equipment can be a significant portion of the total plant layout. In 1990: Estimated CAPEX was $60,000/tpd of CO 2 capture on a 200 tpd gas fired plant E-4 E-3 In 1999: Estimated OPEX for a 1,000 tpd Recovery on a coalfired unit was $18.70/ ton E-6 E-2 P-4 E-5 Page 23

24 CO 2 Capture: Process Chemistry CO 2 extraction (recovery) is energy intensive, and requires unique solvent chemistry tailored to the application CO 2 extraction is more efficient at high pressure, where physical solvents are more effective. At low pressure, i.e. conditions at a typical power plant exhaust stack, only chemical solvents are used Burner Cooling screen Pressur. water inlet Quench water Fuel Pressur. water outlet Oxygen, Steam Granulated slag Cooling jacket Gas outlet Water overflow Gas separation technologies are key to limiting GHG emissions Gas separation of oxygen, CO 2, nitrogen, hydrogen and ammonia Page 24

25 Potential Game Changers? Mississippi Power Plant Ratcliffe IGCC Project Oxy-Fuel Chemical Looping N2 Fuel (CH4) MeO MeO Me Me 582 MW enet Spring 2013 ~65% carbon capture (~3 M tons of CO 2 /year) Siemens scope includes: Two SGT6-5000F gas turbine generators Primary Fuel: High H 2 Syngas Adaptation of existing steam and gas turbine technology CO 2 /H 2 O working fluid in the power turbine section Isolation of CO 2 no solvents Enhanced carbon capture Adaptable for CO 2 use in EOR O2+N2 H2O +CO2 Innovation similar to Oxy-Fuel Oxygen delivered to fuel via a metal oxide CO 2 /H 2 O exits as one stream; N 2 exits the other High thermodynamic efficiencies possible Backup/Startup fuel: Natural gas Capability to extract air for integration, air-blown gasifier Page 25 First demonstration will using a modified Siemens SGT-900 gas turbine in an EOR application Multiple product streams: Electricity, H 2 O, and CO %, including CO 2 extraction But a long development cycle; no commercial units or full scale demonstrations yet

26 Innovative Technology Announcements Recent DOE Awards in new energy conversion technologies Oxy-Fuel Siemens Gas Technology Institute* Pratt & Whitney Rocketdyne* Unity Power Alliance/MIT* Chemical Looping Alstom Power* Babcock & Wilcox* University of Kentucky Research Foundation* Page (*)Announced 26 July Source: Chemical Looping Superconducting Power

27 Summary Power generation technical innovation has evolved rapidly in the last few decades. The US has moved relatively quickly into a period where advanced cycles like the Brayton cycle now dominate new project developments. Required evolution of new design methodologies and materials, notably the expanded role of adapting to extreme temperatures (heat transfer) Required new computation methods to design highly specialized features in the gas flow path (Improved compressor performance and compressor maps, turbine performance) Yielded new combustion system designs that reduce water consumption using premixed combustion to meet restrictive environmental requirements. Also, it brought along new tools for advanced diagnostics-real time monitoring of highly stressed components; predictive monitoring methods to mitigate component failure. This technology (gas turbine) is probably the only core technology capable of achieving compliance with tough environmental regulations air, water, soil, hazardous, etc. Page 27