Advanced Turbine System

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U.S. Department of Energy • Office of Fossil Energy National Energy Technology Laboratory Advanced Turbine Systems Advancing The Gas Turbine Power Industry

Transcript of Advanced Turbine System

Page 1: Advanced Turbine System

U.S. Department of Energy • Office of Fossil EnergyNational Energy Technology Laboratory

AdvancedTurbine

Systems

AdvancingThe Gas Turbine

Power Industry

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In 1992, the U.S. Department of Energy forged partnerships with industryand academia under the Advanced Turbine Systems (ATS) Program to go be-yond evolutionary performance gains in utility-scale gas turbine develop-ment. Agreed upon goals of 60 percent efficiency and single digit NOxemissions (in parts per million) represented major challenges in the fields ofengineering, materials science, and thermodynamics—the equivalent of break-ing the 4-minute mile.

Today, the goals have not only been met, but a knowledge base has beenamassed that enables even further performance enhancement. The successfirmly establishes the United States as the world leader in gas turbine tech-nology and provides the underlying science to maintain that position.

ATS technology cost and performance characteristics make it the least-costelectric power generation and co-generation option available, providing atimely response to the growing dependence on natural gas driven by bothglobal and regional energy and environmental demands.

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Introduction

Through the Advanced TurbineSystems (ATS) Program, lofty vi-sions in the early 1990s are nowemerging as today’s realities in theform of hardware entering the mar-ketplace. An investment by govern-ment and industry in partnershipsencompassing universities and na-tional laboratories is paying signifi-cant dividends. This documentexamines some of the payoffsemerging in the utility sector result-ing from work sponsored by theU.S. Department of Energy (DOE).

Both industrial and utility-scaleturbines are addressed under theATS Program. The DOE Office ofFossil Energy is responsible for theutility-scale portion and the DOEOffice of Energy Efficiency and Re-newable Energy is responsible forthe industrial turbine portion. Thefocus here is on utility-scale workimplemented under the auspices ofthe National Energy Technology

Laboratory (NETL) for the DOEOffice of Fossil Energy.

In 1992, DOE initiated the ATSProgram to push gas turbine perfor-mance beyond evolutionary gains.For utility-scale turbines, the objec-tives were to achieve: (1) an effi-ciency of 60 percent on a lowerheating value (LHV) basis in com-bined-cycle mode; (2) NO

x emis-

sions less than 10 ppm by volume(dry basis) at 15 percent oxygen,without external controls; (3) a 10percent lower cost of electricity; and(4) state-of-the-art reliability, avail-ability, and maintainability (RAM)levels. To achieve these leapfrogperformance gains, DOE mobilizedthe resources of leaders in the gasturbine industry, academia, and thenational laboratories through uniquepartnerships.

The ATS Program adopted a two-pronged approach. Major systems

development, under cost-shared co-operative agreements between DOEand turbine manufacturers, was con-ducted in parallel with fundamental(technology base) research carriedout by a university-industry consor-tium and national laboratories.

Major systems developmentbegan with turbine manufacturersconducting systems studies in PhaseI followed by concept developmentin Phase II. Today, one major systemdevelopment is in Phase III, tech-nology readiness testing, and an-other has moved into full-scaletesting/performance validation.Throughout, the university-industryconsortium and national laborato-ries have conducted research to ad-dress critical needs identified byindustry in their pursuit of systemsdevelopment and eventual globaldeployment.

ATS Program Strategy

Global

Technology Base Research

Universities – Industry – National Labs

Deployment

TechnologyReadiness Testing

(Phase III)

Full-Scale Testing/Performance Validation

ConceptDevelopment

(Phase II)

TurbineManufacturers

SystemStudies

(Phase I)

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Utility-Scale ATS BenefitsThe ATS Program is meeting established objectives, laying a foundation for future advances, and providinga timely response to the burgeoning demand for clean, efficient, and affordable power both here andabroad. ATS technology represents a major cost and performance enhancement over existing naturalgas combined-cycle, which is considered today’s least-cost, environmentally superior electric powergeneration option. Moreover, ATS is intended to evolve to full fuel flexibility, allowing use of gasderived from coal, petroleum coke, biomass, and wastes. This compatibility improves the performanceof advanced solid fuel technologies such as integrated gasification combined-cycle (IGCC) and secondgeneration pressurized fluidized-bed. In summary, the ATS Program does the following:

! Provides a timely, environmentally sound, andaffordable response to the nation’s energyneeds, which is requisite to sustaining economicgrowth and maintaining competitiveness in theworld market

! Enhances the nation’s energy security by usingnatural gas resources in a highly efficientmanner

! Firmly establishes the United States as the worldleader in gas turbine technology; provides theunderlying science to maintain that leadership;and positions the United States to capture a largeportion of a burgeoning world energy market,worth billions of dollars in sales and hundredsof thousands of jobs

! Provides a cost-effective means to address bothnational and global environmental concerns byreducing carbon dioxide emissions 50 percentrelative to existing power plants, and providingnearly pollution-free performance

! Allows significant capacity additions at existingpower plant sites by virtue of its highly compactconfiguration, which precludes the need foradditional plant siting and transmission lineinstallations

! Enhances the cost and performance of advancedsolid fuel-based technologies such as integratedgasification combined-cycle and pressurizedfluidized-bed combustion for markets lackinggas reserves

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Gas Turbine Systems

A gas turbine is a heat enginethat uses a high-temperature, high-pressure gas as the working fluid.Combustion of a fuel in air is usu-ally used to produce the needed tem-peratures and pressures in theturbine, which is why gas turbinesare often referred to as “combus-tion” turbines. To capture the en-ergy, the working fluid is directedtangentially by vanes at the base ofcombustor nozzles to impinge uponspecially designed airfoils (turbineblades). The turbine blades, throughtheir curved shapes, redirect thegas stream, which absorbs the tan-gential momentum of the gas andproduces the power. A series of tur-bine blade rows, or stages, are at-tached to a rotor/shaft assembly.The shaft rotation drives an electricgenerator and a compressor for theair used in the gas turbine combus-

tor. Many turbines also use a heatexchanger called a recouperator toimpart turbine exhaust heat into thecombustor’s air/fuel mixture.

Gas turbines produce high qual-ity heat that can be used to generatesteam for combined heat and powerand combined-cycle applications,significantly enhancing efficiency.For utility applications, combined-cycle is the usual choice because thesteam produced by the gas turbineexhaust is used to power a steamturbine for additional electricitygeneration. In fact, approximately75 percent of all gas turbines arecurrently being used in combined-cycle plants. Also, the trend in com-bined-cycle design is to use asingle-shaft configuration, wherebythe gas and steam turbines are oneither side of a common generator

to reduce capital cost, operating com-plexity, and space requirements.

The challenge of achieving ATStargets of 60 percent efficiency andsingle digit NO

x emissions in parts

per million is reflected in the factthat they are conflicting goals,which magnifies the difficulty. Theroad to higher efficiency is higherworking fluid temperatures; yethigher temperatures exacerbate NO

x

emissions, and at 2,800 oF reach athreshold of thermal NO

x formation.

Moreover, limiting oxygen in orderto lower NO

x emissions can lead to

unacceptably high levels of carbonmonoxide (CO) and unburned car-bon emissions. Furthermore, in-creasing temperatures above the2,350 oF used in today’s systemsrepresents a significant challenge tomaterials science.

Gas Turbine Combined-Cycle

STEAM TURBINE GENERATOR COMPRESSOR POWER TURBINE

GAS TURBINE

STEAM

HEATRECOVERY

STEAMGENERATOR

COMBUSTION SYSTEM

COMBUSTIONTEMPERATURE

FUELGAS

AIR

NOZZLEVANE

TURBINEBLADE

SHAFT

FIRING TEMPERATURE(TURBINE INLET)

TRANSITION

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General Electric Power Systems ATS Turbine

General Electric Power Systems (GEPS), one of two turbine manu-facturers partnering with DOE to bring the ATS into the utility sector, hassuccessfully completed initial development work, achieving or exceedingprogram goals. The resultant 7H ATS technology—a 400-MWe, 60 hertzcombined-cycle system—is part of a larger GEPS H System™ program,which includes the 9H, a 480-MWe, 50 hertz system designed for over-seas markets.

The H System™ is poised to enter the commercial marketplace. GEPShas fabricated the initial commercial units, the MS9001H (9H) andMS7001H (7H), and successfully completed full-speed, no-load tests onthese units at GE’s Greenville, South Carolina manufacturing facility.Having completed testing in 1999, the 9H is preceding the 7H into com-mercial service. The MS9001H is paving the way for eventual develop-ment of the Baglan Energy Park in South Wales, United Kingdom, withcommercial operation scheduled for 2002. The MS7001H ATS will pro-vide the basis for Sithe Energies’ new 800-MWe Heritage Station in Scriba,New York, which is scheduled for commercial service in 2004.

Early entry of the 9H is part of the H System™ development strategyto reduce risk. The 9H incorporates critical ATS design features and pro-vided early design verification. Also, because ATS goals required ad-vancements in virtually all components of the gas turbine,GEPS incorporated its new systems approach for theH System™—the “design for six sigma” (DFSS)design process. DFSS accelerated developmentby improving up-front definition of perfor-mance requirements and specificationsfor subsystems and components, and byfocusing the research and developmentactivities. Downstream, the benefitswill be improved reliability, avail-ability, and maintainability due tointegration of manufacturing andoperational considerations into theDFSS specifications.

GEPS’ 400-tonMS7001H in transit tofull-speed, no-load testing

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Meeting theTechnical Challenges

Turbine

The need to address the conflict-ing goals of higher efficiency andlower NO

x emissions required sys-

temic changes. The major driver wasto increase the firing temperature(temperature into the first rotatingturbine stage) without exceeding theNO

x formation combustion tem-

perature of 2,800 oF. To do so, GEPSintroduced closed-loop steam cool-ing at the first and second stagenozzles and turbine blades (buckets)to reduce the differential betweencombustion and firing temperatures.The closed-loop steam cooling re-placed open-loop air cooling thatdepends upon film cooling of theairfoils.

In open-loop air cooling, a sig-nificant amount of air is divertedfrom the compressor and is intro-duced into the working fluid. Thisapproach results in approximatelya 280 oF temperature drop betweenthe combustor and the turbine rotorinlet, and loss of compressed air en-ergy into the hot gas path. Alterna-tively, closed-loop steam improvescooling and efficiency because ofthe superior heat transfer character-istics of steam relative to air, andthe retention and use of heat in theclosed-loop. The gas turbine servesas a parallel reheat steam generatorfor the steam turbine in its intendedcombined-cycle application.

The GEPS ATS uses a firingtemperature class of 2,600 oF, ap-proximately 200 oF above the mostefficient predecessor combined-cycle system with no increase incombustion temperature. To allowthese temperatures, the ATS incor-

porates several design features fromaircraft engines.

Single crystal (nickel superal-loy) turbine bucket fabrication isused in the first two stages. Thistechnique eliminates grain bound-aries in the alloy, and offers supe-rior thermal fatigue and creepcharacteristics. However, singlecrystal material characteristics con-tribute to the difficulty in airfoilmanufacture, with historic applica-tion limited to relatively small hotsection parts. The transition frommanufacturing 10-inch, two-poundaircraft blades to fabricating blades2–3 times longer and 10 timesheavier represents a significantchallenge. Adding to the challengeis the need to maintain very tightairfoil wall thickness tolerances forcooling, and airfoil contours foraerodynamics.

GEPS developed non-destruc-tive evaluation techniques to verifyproduction quality of single crystalATS airfoils, as well as thedirectionally solidified blades used

in stages three and four. Ultrasonic,infrared, and digital radiographyx-ray inspection techniques are nowin the hands of the turbine bladesupplier. Moreover, to extend theuseful component life, repair tech-niques were developed for the singlecrystal and directionally solidifiedairfoils.

Even with advanced coolingand single crystal fabrication,thermal barrier coatings (TBCs) areutilized. TBCs provide essential in-sulation and protection of the metalsubstrate from combustion gases. Aceramic TBC topcoat provides ther-mal resistance, and a metal bondcoat provides oxidation resistanceand bonds the topcoat to the sub-strate. GEPS developed an airplasma spray deposition process andassociated software for robotic ap-plication. An e-beam test facilityreplicated turbine blade surfacetemperatures and thermal gradientsto validate the process. The TBC isnow being used where applicablethroughout the GEPS product line.

General Electric’s H SystemTM gas turbine showing the 18-stage compressorand 4-stage turbine

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Compressor

To meet H System™ air requirements, GEPS turned to the high-pres-sure compressor design used in its CF6-80C2 aircraft engine. The 7Hsystem uses a 2.6:1 scale-up of the CF6-80C2 compressor, with four stagesadded (bringing it to 18 stages), to achieve a 23:1 pressure ratio and 1,230lb/sec airflow. The design incorporates both variable inlet guide vanes,used on previous systems, and variable stator vanes at the front of thecompressor. These variable vanes permit airflow adjustments to accom-modate startup, turndown, and variations in ambient air temperatures.

GEPS applied improved 3-D computational fluid dynamic (CFD) toolsin the redesign of the compressor flow path. Full-scale evaluation of the7H compressor at GEPS’ Lynn, Massachusetts compressor test facilityvalidated both the CFD model and the compressor performance.

H System™ compressors also circulate cooled discharge air in the ro-tor shaft to regulate temperature and permit the use of steel in lieu ofInconel. To allow a reduction in compressor airfoil tip clearance, the de-sign included a dedicated ventilation system around the gas turbine.

Combustion

To achieve the single digit NOx emission goal, the H System™ uses a

lean pre-mix Dry Low NOx (DLN) can-annular combustor system similar

to the DLN in FA-class turbine service. The H System™ DLN 2.5 combus-tor combines increased airflow resulting from the use of closed-loop steamcooling and the new compressor with design refinements to produce bothsingle digit NO

x and CO emissions.

GEPS subjected full-scale prototype, steam-cooled stage 1 nozzle seg-ments to extensive testing under actual gas turbine operating condi-tions. Testing prompted design changes including applicationof TBC to both the combustor liner and downstream transi-tion piece, use of a different base metal, and modifiedheat treatment and TBC application methods.

GEPS compressorrotor during assembly

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Control System

The H System™ uses an inte-grated, full-authority, digital controlsystem—the Mark VI. The Mark VIalso manages steam flows betweenthe heat recovery steam generator,steam turbine, and gas turbine;stores critical data for troubleshoot-ing; and uses pyrometers to moni-tor stage 1 and stage 2 turbinebucket temperatures. The pyrometersystem offers rapid detection of risesin temperature, enabling automaticturbine shutdown before damageoccurs. The demonstrated successof the Mark VI has prompted GEPSto incorporate it into other (non-steam cooled) engines. Energy Secretary Bill Richardson, flanked by Robert Nardelli of GE and South

Carolina Senator Ernest Hollings, introduced GE’s gas turbine at a ceremonyin Greenville, South Carolina. Richardson stated: “This milestone will not onlyhelp maintain a cleaner environment, it will help fuel our growing economy,and it will keep electric bills low in homes and businesses across our country.”

GE Power Systems has completed its work on the DOE ATSProgram, and has achieved the Program goals. A full scale 7H

(60 Hz) gas turbine has been designed, fabricated, and successfullytested at full speed, no load conditions at GE’s Greenville, SouthCarolina manufacturing/test facility.

The GE H SystemTM combined-cycle power plant creates an entirelynew category of power generation system. Its innovative cooling sys-tem allows a major increase in firing temperature, which allows thecombined-cycle power plant to reach record levels of efficiency andspecific work, while retaining low emissions capability, and with reli-ability parameters comparable to existing products.

The design for this “next generation” power generation system is nowestablished. Both the 9H (50 Hz) and the 7H (60 Hz) family membersare currently in the production and final validation phase. The exten-sive component test validation program, already well underway, willensure delivery of a highly reliable combined-cycle power generationsystem.

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Siemens Westinghouse PowerCorporation (SWPC) has intro-duced into commercial operationmany key ATS technologies. Oper-ating engine demonstrations andongoing technology developmentefforts are providing solid evidencethat ATS program goals will beachieved.

In response to input from itscustomer advisory panel, SWPC isintroducing advanced technologiesin an evolutionary manner tominimize risk. As performance isproven, SWPC is infusing ATS tech-nologies into commercially offeredmachines to enhance cost and per-formance and expand the benefit ofthe ATS program.

Siemens Westinghouse Power CorporationATS Turbine

The first step in the evolution-ary process was commissioning ofthe W501G. This unit introducedkey ATS technologies such asclosed-loop steam cooling, ad-vanced compressor design, andhigh-temperature materials. Afterundergoing extensive evaluationat Lakeland Electric’s McIntoshPower Station in Lakeland, Florida,the W501G entered commercial ser-vice in March 2000. Conversion tocombined-cycle operation is sched-uled for 2001.

The next step is integration ofadditional ATS technologies into theW501G, with testing to begin in2003. The culmination will be dem-

onstration of the W501ATS in 2005,which builds on the improvementsincorporated in the W501G.

LeveragingATS Technology

The following discusses theATS technology introduced duringcommissioning of the 420-MWeW501G and currently being incor-porated in other SWPC gas turbinesystems. The combustion outlettemperature in these tests waswithin 50 oF of the projected ATStemperature.

Closed-LoopSteam Cooling

The W501G unit applied closed-loop steam cooling to the combus-tor “transitions,” which duct hotcombustion gas to the turbine inlet.Four external connections routesteam to each transition supplymanifold through internal piping.The supply manifold feeds steam toan internal wall cooling circuit.After the steam passes through thecooling circuit, it is collected in anexhaust manifold and then is ductedout of the engine.

Testing at Lakeland proved theviability of closed-loop steam cool-ing, and confirmed the ability toswitch between steam and air cool-ing. The steam cooling clearlydemonstrated superiority over aircooling.

Steam-cooled “transition”

Siemens WestinghouseW501G

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Optimizing Aerodynamics

In parallel with W501G testing,SWPC validated the benefits of ap-plying the latest three-dimensionaldesign philosophy to the ATS four-stage turbine design. This was con-ducted in a one-third scale turbinetest rig, incorporating the first twostages. SWPC conducted the test-ing in a shock tube facility at OhioState University, which was instru-mented with over 400 pressure, tem-perature, and heat flux gauges. Anaerodynamic efficiency increase at-tributed to the use of “indexing” sur-passed expected values.

High-Temperature TBCs

TBCs are an integral part of theW501ATS engine design. An on-going development program evalu-ated several promising bond coatsand ceramic materials prior to theW501G tests. The selected ad-vanced bond coat/TBC system un-derwent 24,000 hours of cyclicaccelerated oxidation testing at1,850 oF. The W501G incorporatedthe selected TBC on the first andsecond row turbine blades. Plansare to incorporate the TBC systeminto other SWPC engines.

Compressor

The W501G incorporates thefirst 16 stages of the 19 stage ATScompressor, designed to deliver1,200 lb/sec airflow with a 27:1pressure ratio. SWPC slightlymodified the last three stages for theW501G compressor and changedvanes 1 and 2 from modulated tofixed. This resulted in air deliveryat the ATS mass-flow rate of 1,200lb/sec, but at a pressure ratio of 19:1,which optimizes the compressor forthe W501G system.

The roots of the compressordesign are in three-dimensional vis-cous flow analyses and custom de-signed, controlled-diffusion airfoilshapes. Controlled-diffusion airfoildesign technology evolved from theaircraft industry. The airfoils emerg-ing from these analytical methodsare thinner and shaped at the endsto reduce boundary layer effects.

To verify the aerodynamic per-formance and mechanical integrityof the W501ATS compressor, a full-scale unit was manufactured andtested in 1997. SWPC confirmedperformance expectations throughextensive, highly instrumented testsin a specially designed facility at thePhiladelphia Naval Base.

The ATS compressor technol-ogy has been retrofitted into theW501F product line using analyti-cal techniques developed andproven under the ATS program.This significantly expands the ben-efit of the ATS program,given projected salesfor this popularsized unit.

SiemensWestinghouseATS compressor

Aerodynamic redesign

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ATS Row 4Turbine Blade

To accommodate the 25 percentincrease in mass flow associatedwith the ATS compressor, theW501G uses the ATS Row 4 turbineblade assembly. The new designuses a large annulus area to reducethe exit velocity and capture themaximum amount of the gas flowkinetic energy before leaving theturbine. The uncooled ATS Row 4turbine blade assembly met pre-dicted performance levels through-out the W501G test program andestablished a new level in gas tur-bine output capability.

Brush Seals andAbradable Coatings

The W501ATS design appliesbrush seals to minimize air leakageand hot gas ingestion into turbinedisc cavities. Seal locations includethe compressor diaphragms, turbinedisc front, turbine rims, and turbineinterstages. SWPC used test rigs todevelop effective, rugged, and reli-able brush seals for the various ap-plications. ATS compressor tests atthe Philadelphia Naval Base veri-fied brush seal low leakage and wearcharacteristics, which resulted inapplication of the seals to W501Fand W501G product lines. Retrofit-ted units have demonstrated signifi-cantly improved performance.

Abradable coatings on turbineand compressor blade ring seals arealso a part of the W501ATS design.This approach permits reduced tipclearances without risk of hardwaredamage, and provides more uniformtip clearance around the perimeter.Stage 1 turbine ring segment condi-tions present a particular challenge,requiring state-of-the-art thermalbarrier properties while providingabradability. Engine testing verifiedthe targeted abradability, tip-to-sealwear, and erosion characteristics.The coatings have been incorpo-rated into the compressor and thefirst two turbine stages ofboth the W501F andW501G machines.

SiemensWestinghouseW501G atLakeland Electric’sMcIntosh PowerStation, Lakeland, Florida

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CompletingATS Development

Development activities are fo-cused on extending the W501G per-formance to ATS efficiencies byintroducing additional technologyadvancements and increasing thefiring temperature to 2,750 oF.

Closed-LoopSteam Cooling

The next major step will be in-corporation of closed-loop steamcooling into the W501G stage 1 tur-bine vane. This addition will extendthe benefits of the existing steamcooled transition by eliminatingcooling air at the turbine inlet, rais-ing the firing temperature, and free-ing more compressor air to reduceNO

x emissions.

Prior to retrofitting into theW501G, the ATS steam cooled vaneunderwent evaluation in a test rigincorporating a single full-scalecombustor and transition capable ofachieving ATS temperatures andpressures. The tests were con-ducted at the Arnold Air ForceBase-Arnold Engineering De-velopment Center in Tennes-see. Instrumentation verifiedanalytical predictions of metaltemperatures, heat transfer co-efficients, and stress. SWPCreleased the stage 1 turbinevane for manufacture and sub-sequent installation in theW501G, with testing sched-uled for 2001.

Plans for the W501ATS are toincorporate closed-loop steam cool-ing into both stage 1 and stage 2vanes and ring segments.

Catalytic Combustion

To achieve NOx emission tar-

gets across a wide range of ATSoperating conditions, SWPC is de-veloping a catalytic combustor inconjunction with Precision Com-bustion, Inc. (PCI) under DOE’sSmall Business Innovation Re-search Program. Catalytic com-bustion serves to stabilize flameformation by enhancing oxidationunder lean firing conditions. TheSWPC/PCI piloted-ring combustorwill replace the standard diffusionflame pilot burner with a catalyticpilot burner. Initial atmosphericpressure combustion testing deter-mined turndown and emissioncharacteristics. Follow-on testssuccessfully demonstrated catalyticcombustion at full-scale under ATScombustion temperatures and pres-sures. Engine testing is planned forearly 2001.

Materials

An active materials develop-ment program has been ongoing tosupport incorporation of singlecrystal and directionally solidifiedturbine blade alloys and steam cool-ing into the ATS design. The pro-gram has addressed the effect ofsteam cooling on materials, bladelife prediction, advanced vane al-loys, single crystal and directionallysolidified blade alloy properties,and single crystal airfoil casting.Single crystal casting trials, using aCMSX-4 alloy on first stage vanesand blades, demonstrated the viabil-ity of casting these large compo-nents with their thin-wall coolingdesigns. But alternative manufac-turing methods and alloys are be-ing explored to reduce cost.

SWPC plans to use a new ce-ramic TBC emerging from the OakRidge National Laboratory ThermalBarrier Coatings Program—a partof the ATS Technology Base Pro-gram. The ceramic TBC, compat-ible with ATS temperatures, will beintegrated with the new bond coatevaluated by SWPC earlier in theW501G tests.

Siemens Westinghouse is fur-ther expanding the benefits

of the ATS program by intro-ducing ATS-developed tech-nologies into its mature productlines. For example, the latestW501F incorporates ATS brushseals, coatings, and compressortechnology. Because the F frameaccounts for a majority of cur-rent new unit sales, this infusionof technology yields significantsavings in fuel and emissions.

Catalytic pilot flame, which providesstability to the swirler flame

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As indicated in the GeneralElectric and Siemens Westinghousediscussions, firing temperaturesused in the ATS gas turbines ne-cessitate materials changes in thehot gas path, particularly in thefirst two turbine stages. Moreover,new manufacturing techniques areneeded to affect the materialschanges. While single crystal anddirectionally solidified turbineblades are being used on aircraftengines, these parts are far smallerand one-tenth the weight of ATSutility-scale machines, and requireless dimensional control.

To support the major systemsdevelopment efforts, Oak RidgeNational Laboratory has coordi-nated a materials and manufactur-ing technology program to hastenthe incorporation of single crystalcast components into the ATS hotgas path.

Single CrystalCasting

General Electric and PCCAirfoils (GE-PCC) teamed up toaddress the challenges of bringingcost-effective single crystal (SX)technology to land-based gas tur-bine engine applications. As notedby General Electric, the require-ments for grain perfection and thosefor accurate part geometry competewith one another and create formi-dable challenges to successful, wide-spread use of large, directionallysolidified (DS) and single crystal(SX) parts.

The GE-PCC work has pro-duced a number of findings and ad-vances in casting technology thatwill enable General Electric to in-corporate higher-yield SX and DScomponents into their ATS unit.Early work determined that signifi-cant improvement in oxidation re-sistance resulted from reducingsulfur levels to 1.0–0.5 ppm in thesuper nickel alloy used. GE-PCCdeveloped a low-cost melt desulfu-rization process to replace expen-sive heat treatment methods forsulfur removal.

In parallel, GE-PCC advancedthe casting and silica core processesto enable SX manufacture of com-plex-cored and solid airfoils forland-based turbine applications.Also explored was the use of alu-

mina ceramic formulated core ma-terials to provide enhanced stabilityand dimensional control. Prototypetesting showed promise for com-mercial application. Liquid metalcooling (LMC) was evaluated forapplication to DS processing. LMCprovides increased thermal gradi-ents without increasing the castingmetal temperature by improvingheat input and removal from cast-ings. Casting of large stage-2 buck-ets for a 9G prototype machine wassuccessfully demonstrated.

Siemens Westinghouse is de-veloping a process to fabricate com-plex SX blades and vanes fromsmall, readily producible castingsusing transient liquid phase bond-ing. Transient liquid phase bond-ing was developed in the 1970s by

Transferring Aerospace Technologyto Land-Based Systems

General Electric’s liquid metal cooling furnace

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Pratt & Whitney for aircraft enginecomponents. The bonding mediacontains a melting point depressantand a carefully selected subset of theparent metal chemistry to attain 90percent of the base metal properties.In the fabricated component ap-proach, bond planes are placed ininsensitive locations.

Siemens Westinghouse, in con-junction with the National Institutefor Science and Technology (NIST),PCC, and Howmet, has moved thefabricated component approach toprototype production. Efforts havedetermined segments and bondingplanes, developed coreless SX cast-ing technology for the segments,developed fixtures to bond the seg-ments, verified the structural integ-rity, and designed non-destructiveevaluation (NDE) methods. Bothfabricated stage 1 vanes and bladesare to be used on the SWPC ATS unit.

Howmet Research Corpora-tion is pursuing ways to enhance SXand DS casting technology towardimproving yields for the large ATShot gas path components. Activitiesare focused on: (1) improving cur-rent Vacuum Induction Melt (VIM)furnace capability and control; (2)

addressing deficiencies in currentshell systems; and (3) investigatingnovel cooling concepts for increasedthermal gradients during the solidi-fication process.

The thrust of the VIM furnaceefforts is definition of the factorsthat will improve control of moldtemperatures and thermal gradients.Howmet conducted furnace surveyson the GEPS 9H blade casting pro-cess to update and validate a solidi-fication process model. Computermodels were also developed to ana-lyze potential and current furnacematerials. These models will pro-vide the tools to optimize the VIMfurnace design. Howmet has dem-onstrated that improvements of upto 40 percent in the thermal gradi-ent are attainable by enhancing thecurrent system.

The shell systems activities ad-dress the additional requirementsimposed on the ceramic mold withincreased casting size. For example,longer casting times induce shellcreep, thicker shells reduce thermal

Fabricated blade showing bondingplane

Fabricated blade, showing complexityof internals

gradients, and the larger and heaviermolds lead to structural and handlingproblems. Howmet investigatedmaterials additives to strengthen theshell, and additives to improve ther-mal conductivity. Under some con-ditions, additives reduced creepdeflection by 25–90 percent. Simi-larly, material additives achievedimprovements in thermal conduc-tivity of up to five times under someconditions.

As indicated above, maintain-ing a high thermal gradient at thesolidification front is critical to pre-venting casting defects and enhanc-ing yields. Novel cooling methodshave the potential for achievingrevolutionary increases in thermalgradients. The research being car-ried out is defining the heat transfermechanisms necessary to designsuch novel cooling methods. Workto date has shown that the maximumthermal gradient may be limited bythree rather than one resistancemechanism. By identifying theprincipal rate limiting thermal char-acteristic, a significant increase inthermal gradient may be achieved.

The advances in materials andmanufacturing technology

needed to effectively transferaerospace technology to thelarge land-based turbine systemsrepresented the single greatestchallenge to meeting ATS goals.Only through mutual investmentsin extensive R&D under ATS part-nerships was the challenge suc-cessfully met and a foundationlaid for further advancement.

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NETL conducts combustion re-search in partnership with in-

dustry and university-industry con-sortia to address the challengesassociated with achieving sub-stantial gains in efficiency and en-vironmental performance, andexpanding fuel options for gas tur-bines. As discussed previously,moving to higher temperatures andpressures for efficiency improve-ment conflicts with the need forlow emissions. Using new gas tur-bine cycles and operating on lowerenergy density renewable or op-portunity fuels introduce addi-tional demands on combustion.

To address combustion chal-lenges, NETL’s on-site researchsupports the ATS program by devel-oping and evaluating new technol-ogy for ATS applications. TheNETL laboratories have providedpublic data on various issues asso-ciated with low-emission combus-tion, including the stability behaviorof low-emission combustion, novelcombustor concepts, and combus-tion in new engine cycles.

The NETL research is oftencarried out through partnershipswith industrial or academic col-laborators. Cooperative Researchand Development Agreements(CRADAs) can be used to protectparticipants’ intellectual property,while other approaches such as shar-ing public data have produced ben-efits to the various members of theturbine community. The followingactivities exemplify NETL’s gas tur-bine research.

Surface StabilizedCombustion

NETL teamed with Alzeta Cor-poration to investigate a new ap-proach to ultra-low-NO

x (2 ppm or

less) combustion under high tem-perature and pressure regimes—Sur-face-Stabilized Combustion (SSC).The Low Emissions Combustor Testand Research (LECTR) facility atNETL provided the test platform forthe investigation. LECTR is readilyadaptable to a variety of combustordesigns, and is capable of deliver-ing representative gas turbine tem-peratures and pressures.

SSC may offer improved perfor-mance compared to existing DLNcombustors, which use high excess

air levels to reduce flame tempera-tures and thus NO

x emissions.

The SSC DLN burner uses a thin,compressed, and sintered porousmetal fiber mat (Pyromat) at theburner inlet to stabilize combustion.The Pyromat stabilizes combustionby maintaining the presence of ahigh-temperature surface in thefuel-air flow path.

Testing at NETL defined thekey parameters and operating enve-lope, and refined the design. Sub-sequent testing in conjunction withSolar Turbines validated ultra-low-NO

x and

low CO emissions per-

formance, further developed thehardware, and positioned the tech-nology for commercialization.

Advancing Combustion Technology ThroughNETL Partnerships

NETL Dynamic Gas Turbine Combustor

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15

Humid AirCombustion

The Humid Air Turbine (HAT)cycle is an advanced gas turbinecycle in which water-saturated airis introduced along with gaseous fu-els, and is combusted at high pres-sure. Projected advantages arereduced NO

x, and enhanced power

output gained by increasing massflow through the turbine. The HATcycle could potentially provide alow-cost option for power genera-tion, with high thermal efficiencyand rapid startup time.

A NETL partnership with UnitedTechnologies Research Center andPratt & Whitney addressed actualHAT cycle combustion characteris-tics using the LECTR facility. Aunique method to produce coinci-dent ultra-low-NO

x and CO levels

was found in tests of an air-cooledcombustion liner. The results wereused to further develop HAT cyclemodeling efforts. Previous investi-gations on the HAT cycle had largelybeen limited to systems and model-ing studies.

Duel-FuelCombustion

Many gas turbine installationsrequire operation on both liquid andgaseous fuels without affecting op-erability or environmental perfor-mance. Liquid fuels are more difficultto mix and pose difficulties inachieving the homogeneous fuel-airmixture distribution that is neededfor low-NO

x combustion.

Under a CRADA, NETL andParker Hannifin evaluated a noveldual fuel pre-mixer concept using amanufacturing technique called“macrolamination.” This techniqueallows complex internal flow chan-nels to be formed by etching theminto thin substrates and bonding thesubstrates together to form fuel in-jector arrays.

Testing at NETL showed thatthe Parker Hannifin pre-mixer en-abled comparable environmentalperformance with both natural gasand type 2 diesel fuel at representa-tive temperatures and pressures.

StabilizingCombustion

DynamicsCombustion oscillations (or

dynamics) continues to be a chal-lenging issue for the design of low-emissions combustors. Oscillationsoften complicate achievement ofemissions goals, or limit engine ca-pability for new fuels or new re-quirements. To address this issue,NETL has conducted various re-search projects to identify methodsto improve combustion stability.These investigations have identifiedimportant time scales that can bemodified to improve combustion

performance. In partnership withthe Pittsburgh SupercomputingCenter, NETL has explored the dy-namic structure of turbine flames.The results are being used to under-stand how the dynamic combustionresponse can be modified to enhancestability. In addition, through anAGTSR award, Virginia Tech hasconducted a series of acoustic testsin the NETL facilities that havedemonstrated promising methodsto evaluate the acoustic response ofturbine combustors. Methods tomeasure both the acoustic and com-bustion responses are vital to en-hance the stability of low-emissioncombustors and achieve the goals oftomorrow’s advanced combustionsystems.

Another promising approach toenhance combustion stability iscalled “active” dynamics control.Active control pulses the fuel to re-lease heat out-of-phase relative tothe oscillation. Through a CRADA,NETL and Solar Turbines recentlyexplored a variation of active com-bustion dynamics control, calledperiodic equivalence ratio modula-tion (PERM). In applying PERM,adjacent injectors alternately injectfuel at a modulated frequency. Thismodulation serves to dampen pres-sure pulses from any particular in-jector, while maintaining a desiredtime-averaged fuel-air ratio (equiva-lence ratio). Testing on a 12-injec-tor engine showed that PERMeffectively eliminated a 3-psi peak-to-peak pressure oscillation. Modu-lation was carried out at frequenciesfrom 10 to 100 hertz without notice-able effect on engine performance.

Macrolaminate fuel injector array,shown here after testing, is used fordual-fuel applications – Photocourtesy of Parker Hannifin

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Establishing the Scientific Foundation forthe 21st Century Gas Turbine

Anchoring ATS efforts to pro-vide the underlying science (tech-nology base research)—requisitefor major systems developments—is the Advanced Gas Turbine Sys-tems Research (AGTSR) Program.AGTSR is a university/industryconsortium that has grown into avibrant virtual laboratory with na-tional scope and worldwide recog-nition. Since its inception in 1992,AGTSR has networked the partici-pation of 100 universities in 38states, and 10 major players in thegas turbine industry. Through net-working research activities, AGTSRhas exponentially increased the in-teractions among researchers andinterested parties, breaking the moldof traditional one-on-one universityresearch (researcher and fundingagency). Moreover, AGTSR has notonly established a body of scientificexcellence in gas turbine technology,but provided for continued U.S. lead-ership in turbine technology throughan ongoing education program.

With DOE oversight and indus-try guidance, the South Carolina In-stitute for Energy Studies (SCIES)administers the AGTSR Program,providing the linkage between uni-versities, industry, and government.A 10-member Industry ReviewBoard (IRB) provides corporateleaders who define the thrust of theresearch program and technicalexperts to evaluate research pro-posals. IRB membership includesgas turbine manufacturers, partssuppliers, customers, and indus-try research and development or-ganizations. SCIES coordinates the

research efforts, creates teams ofexcellence in the various fields ofendeavor, conducts workshops, andarranges internships and fellowshipsas part of an education program.

Research remains the primarymission of AGTSR. But as the pro-gram matured, other functionsemerged as a consequence of theprogram’s success. Workshops be-came necessary for effective tech-nology transfer. And educationactivities became a natural outgrowthto sustain scientific excellence, suchas internships, fellowships, facultystudies, and special studies. To date,16 separate universities around thecountry have sponsored workshopson key topics. All interns wereeventually employed by the gas tur-bine industry or by a university. Wellover 400 university personnel andover 100 industry experts haveparticipated directly in the AGTSRprogram.

The structure of AGTSR servesto ensure the quality, relevance, andtimeliness of the research. Thequality of research is assured byuniversity peer review at work-shops and through the publicationprocess. Relevance of the researchis established by having industry de-fine the research needs, select theresearch, and critique the results.Timeliness is guaranteed by in-dustry and DOE involvement withPerforming Member institutionsthroughout the life of the projects.

The creation of a national net-work of universities under

AGTSR mobilized the scientifictalent needed to understandthe fundamental mechanismsimpeding gas turbine perfor-mance gains and to identifypathways for overcoming them.

AGTS professor and graduate student reviewing progress on their project

Page 19: Advanced Turbine System

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Examples of SuccessThe successes in the AGTSR

program are too numerous to re-count. The following examples areoffered to exemplify the work car-ried out in the three program areas.

Combustion

Instability Control for LowEmissions Combustors—GeorgiaTech. Gas turbine design today in-corporates lean pre-mix combustionto reduce NO

x emissions. Effective

mixing of the high volume of air withthe fuel for lean combustion is dif-ficult and often leads to combustioninstability that can cause vibrationand damage, or turbine shutdown.Georgia Tech developed an auto-matic means to actively detect theonset of combustion instabilities,identify combustion characteristics,and “instantaneously” attenuate theunstable mode. Georgia Tech firstfabricated a low-NO

x gas turbine

simulator to develop the Active Con-trol System. Siemens Westinghousecarried out successful verificationtesting on a full-scale 3-MW gasturbine combustor. The observedfour-fold reduction in amplitudes ofcombustion pressure oscillationsrepresents a major milestone in theimplementation of active combus-tion control. Two patents have beenissued on the Georgia Tech technol-ogy, a third is pending, and the tech-nology is being transferred toindustry. NASA has purchased anActive Control System for testing.

Computer Code Improve-ments for Low Emission Combus-tor Design—Cornell University. Itis crucial for low emission turbinecombustor design codes to accu-rately predict NO

x and CO emis-

sions. To date, computer codes used

for combustor emission design haveeither impractically long run times,or have unacceptable computationalinaccuracies. Cornell University hasimproved significantly upon an insitu adaptive tabulation (ISAT) al-gorithm, which reduces computercomputation times for combustionchemistry by a factor of 40. In con-trolled piloted jet flame validationtests, the improved ISAT accuratelypredicted NO

x and CO levels, as well

as local extinction and re-ignition.At least one gas turbine manufac-turer has already incorporated theimproved ISAT algorithm into theircombustor design system.

Aerodynamicsand Heat Transfer

Advanced Component Cool-ing for Improved Turbine Perfor-mance—Clemson University .Materials and air cooling tech-niques—used in the past to enablehigh turbine inlet temperatures andresulting performance benefits—areapproaching limits of diminishingreturns. Accordingly, General Elec-tric and Siemens Westinghouse are

using steam cooling for their veryhigh temperature ATS turbines.Clemson University has conductedexperiments in four test configura-tions to show that steam cooling per-formance is substantially improvedby adding small quantities of watermist. Depending on the test con-figuration, an addition of 1 percent(by weight) of mist typically en-hanced cooling heat transfer by 50–100 percent, and in best cases, byas much as 700 percent. By quanti-fying the potential benefits and de-fining key parameters, Clemson hasprovided the scientific underpin-ning to support development of anext generation closed-loop coolingsystem.

Active Control System identifies combustion instabilities and instantaneouslyattenuates the unstable mode

Control Off Control OnIdentification

Time (sec)

10 2 3 4 5 6

1.5

1

0.5

0

-0.5

-1

Pressure Control Signal

Page 20: Advanced Turbine System

18

Simplified Method for Evalu-ating Aerodynamic Interactionsbetween Vane/Blade Rows—Mas-sachusetts Institute of Technol-ogy. Reducing efficiency losses, dueto aerodynamic interactions be-tween adjacent rows of stationaryvanes and rotating blades, is anotherimportant approach to improvinggas turbine performance. However,the computer codes that are capableof aerodynamic analyses of the un-steady effects and complex geom-etry of adjacent airfoil rows requireextensive manpower efforts to setup, multiple computer runs, andvery long run times. Such analysesoften require resources and time inexcess of those available for a tur-bine development program. In aproject coordinated with Solar Tur-bines, Massachusetts Institute ofTechnology (MIT) has been develop-ing a relatively simple aerodynam-ics analysis approach to representthe unsteady effects on compressorrotor blades resulting from theirrelative motion with respect to thedownstream stationary stator vanes.MIT has conducted computer aero-dynamic analyses to show that thisunsteadiness effect is negligible andthe downstream stators can be rep-resented by a time-averaged pres-sure profile for the conditionsanalyzed. MIT is now seeking todelineate the general conditions un-der which this observation holds.For those conditions, the signifi-cance of the MIT results is thatmultiple expensive computer runsrepresenting adjacent blade-vanerows will not be needed to deter-mine rotor aerodynamic perfor-mance. Only a single run, using atime-averaged downstream pressureprofile, is needed.

Materials Research

Non-Destructive Evaluationsof Thermal Barrier Coatings—University of Connecticut andUniversity of California, SantaBarbara. The University of Con-necticut (UCONN) and University ofCalifornia, Santa Barbara (UCSB)are developing NDE methods forTBCs. NDE methods are needed toimprove TBC manufacturing qual-ity and operational lifetime incon-sistencies, which have impeded thefull implementation of the turbinepower and efficiency benefits de-rived from TBCs. The need is sogreat and the results from a pastAGTSR project are so promisingthat several of the U.S. gas turbinemanufacturers, a coating supplier,and an instrument maker are provid-ing a substantial in-kind and directcost-share for this current AGTSRproject. One expected output fromthis project is a low-cost and por-table prototype NDE instrumentfor TBCs, which will be used by tur-bine manufacturers, overhaul fa-cilities, and coating suppliers. Inseparate coordinated efforts, UCONNand UCSB are using laser tech-niques differently for NDE evalua-

tions. UCONN uses laser techniquesto measure stresses in coated labo-ratory specimens cycled to failureand coated engine parts from thefield. Correlation of the laser sig-nals with TBC stress degradation isused to assess remaining TBC life.UCSB complements laser measure-ments of degraded materials prop-erties with mechanistic modeling topredict remaining life. Both projectshave demonstrated laser signal cor-relation with life-affecting properties.

Small-Particle Plasma SprayTBCs—Northwestern University.Northwestern University has dem-onstrated a small-particle plasmaspray (SPPS) process to producenovel TBCs. SPPS allows smallparticles to be placed into theplasma in a more controlled man-ner to reduce powder vaporizationand produce less open porosity.Multiple micrometer thick layersare used in lieu of a single coat toenhance toughness. Also, gradedporosity can be applied to enhancethermal conductivity and elasticproperties. Testing has shown bothimproved thermal conductivity andoxidation resistant behavior.

Laser fluorescence testing in support of NDE development at UCONN & UCSB

As-Deposited Engine Tested

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Air Force Institute of TechnologyUniversity of Alabama, HuntsvilleArizona State UniversityUniversity of ArkansasArkansas Tech UniversityAuburn UniversityBrigham Young UniversityCalifornia Institute of TechnologyUniversity of California, BerkeleyUniversity of California, DavisUniversity of California, IrvineUniversity of California, San DiegoUniversity of California,

Santa BarbaraCarnegie Mellon UniversityUniversity of Central FloridaUniversity of CincinnatiClarkson UniversityClemson UniversityCleveland State UniversityUniversity of Colorado, BoulderUniversity of ConnecticutCornell UniversityUniversity of DaytonUniversity of DelawareUniversity of DenverDrexel UniversityDuke UniversityEmbry-Riddle Aeronautical

UniversityFlorida Atlantic UniversityFlorida Institute of TechnologyUniversity of FloridaGeorgia Institute of TechnologyUniversity of Hawaii, ManoaUniversity of HoustonUniversity of IdahoUniversity of Illinois, ChicagoIowa State UniversityUniversity of IowaUniversity of KansasUniversity of KentuckyLehigh UniversityLouisiana State UniversityUniversity of Maryland,

College ParkUniversity of Massachusetts, LowellMercer University

Michigan State UniversityMichigan Technological UniversityUniversity of MichiganUniversity of MinnesotaMississippi State UniversityUniversity of Missouri-RollaMassachusetts Institute

of TechnologyUniversity of New OrleansState University of NY, BuffaloState University of NY,

Stony BrookNorth Carolina State UniversityUniversity of North DakotaNortheastern UniversityNorthwestern UniversityUniversity of Notre DameOhio State UniversityUniversity of OklahomaPennsylvania State UniversityUniversity of PittsburghPolytechnic University (New York)Princeton UniversityPurdue UniversityRensselaer Polytechnic InstituteUniversity of South CarolinaSouthern UniversityUniversity of Southern CaliforniaUniversity of South FloridaStanford University

Stevens Institute of TechnologySyracuse UniversityUniversity of TennesseeUniversity of Tennessee

Space InstituteTennessee Technological

UniversityTexas A&M UniversityUniversity of Texas, ArlingtonUniversity of Texas, AustinUniversity of TulsaUniversity of UtahValparaiso UniversityVanderbilt UniversityVirginia Polytechnic InstituteUniversity of VirginiaWashington UniversityUniversity of WashingtonWashington State UniversityWayne State UniversityWestern Michigan UniversityWest Virginia UniversityUniversity of Wisconsin, MadisonUniversity of Wisconsin,

MilwaukeeWichita State UniversityWorcester Polytechnic InstituteWright State UniversityUniversity of WyomingYale University

AGTSR Performing Members

AGTSR Industrial Project Partners

There are ten industrial turbine developers participating in the project. Each

company contributes $25,000 (non-voting $7,500) a year to the program.

" EPRI (non-voting)" General Electric Power

" Honeywell Engine Systems

" Parker Hannifin (non-voting)

" Pratt & Whitney

" Rolls-Royce Allison

" Solar Turbines

" Southern Company Services(non-voting)

" Siemens Westinghouse

" Woodward FST (non-voting)

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The ATS Program by any mea-sure is a resounding success. Muchof the technology developed underthe Program is already being incor-porated into existing products andtwo 400-MWe ATS units are poisedto enter commercial service. Revo-lutionary goals set in the early 1990shave been met or surpassed. Thisaccomplishment, while proving theskeptics wrong, further substanti-ated the tremendous potential inher-ent in mobilizing the nation’s besttalents to achieve difficult strategicobjectives.

Another related challenge awaits.Gas turbines are being called uponto meet other strategically importantmarket needs. Utility restructuring,increasingly stringent environmen-

tal regulations, and a growing de-mand for peaking power, intermedi-ate duty, and distributed generationare combining to establish the needfor a next generation of turbine sys-tems. The market is quite large andthe payoff in environmental andcost-of-electricity benefits are greatthrough improvements in efficiencyand reduction of emissions levels,particularly with the 50-year re-placement cycle. But competitiveforces embodied in utility restruc-turing that are driving this marketneed are also making it difficult forthe power industry to invest in highrisk research and development.

The time is right for a Next Gen-eration Turbine Program that againmobilizes the nation’s best talents,

Taking the Next Step

but for a different set of needs. In-termediate sized flexible turbinesystems will be required to operateeffectively over a wide range of dutycycles, with a variety of fuels, whileachieving 15 percent efficiency andcost-of-electricity improvements.To achieve greater than 70 percentefficiency, the challenge of devel-oping Turbine/Fuel Cell Hybrids, awhole new cycle, will have to beundertaken. These leapfrog perfor-mance goals are made possible bythe technological advances achievedunder the ATS Program, coupledwith the experience gained in forg-ing private-public partnerships withindustry, academia, and the nationallaboratories.

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Next Generation Turbine ProgramThe Department of Energy has launched the Next Generation Turbine (NGT) Program in response toneeds identified in market and public benefit analyses and workshops structured to obtain stakeholderinput.

The NGT Program addresses the challenges of:! Providing continued energy security through reduced fuel consumption and dependence on

imported fuel supplies;! Protecting citizens from the threat of pollution and global climate change through major efficiency

and environmental performance gains; and! Ensuring that the nation’s electricity supply system remains affordable, robust, and reliable through

lowering life-cycle costs and advancing reliability, availability, and maintainability (RAM) technology.

There are three elements in the NGT Program:! Systems Development and Integration includes the government-industry partnerships needed to

develop low-cost, fuel and duty flexible gas turbines and hybrid systems that are responsive to theenergy and environmental demands of the 21st century.

! RAM Improvements provide the instrumentation, analytical modeling, and evaluation techniquesnecessary to predict impending problems and establish maintenance requirements based on gasturbine operational characteristics.

! Crosscutting Research and Development provides the underlying science in combustion, materi-als, and diagnostics needed to support new technology development.

Benefits will include:! Conservation of natural resources (water and land);! Reduced air emissions (CO2, NOx, SOx);! Lower primary energy consumption (oil, coal, or natural gas depending on the region);! Lower cost-of-electricity;! Improved system reliability;! Improved competitiveness in the world market; and! Job creation.

Page 24: Advanced Turbine System

For More Information

Abbie W. LayneProduct ManagerNational Energy Technology LaboratoryAdvanced Turbines & Engines Systems(304) [email protected]

Heather QuedenfeldNational Energy Technology LaboratoryCommunications and Public Affairs Division(304) [email protected]

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