Microturbine Generators for FC/MTG Hybrid Power Systems

United Technologies Microturbine Generators - Hybrid Power Systems 2002 Overview 1

Microturbine Generators forFC/MTG Hybrid Power Systems

Michael Sahm, Fellow, Turbomachinery and Energy ConversionTom Rosfjord, Microturbine Program Leader

United Technologies Research Center

Presentation to the Second DOE/UN International Conference and Workshop on Hybrid Power Systems

17 April 2002


Base Program launched with DTE Energy Technology March 2000 • Driving DTE Energy Technology’s ENT400 package• DTE Energy: controls, power switching & package • Turbo Genset Company: generator & inverter• PWC: ST5 natural gas fuel turbine

Growth path established:! Prove out base machine• Adapt base machine through component improvement• Couple with bottoming cycle to achieve DOE goal of 40% efficiency

2002 Milestones leading to 40% Electrical Efficiency Demonstration in 2004! Feb 2002: Demonstrate 80 kW from ORC• Aug 2002: Demonstrate 5-point increase in system electrical efficiency with

ORC • Sep 2002: Perform integrated microturbine/ORC test (September 02)• Nov 2002: Demonstrate combustor emissions technology for NOx<7 ppm and

CO<10 ppm

Rapid Birth and Evolution of Distributed Generation Strategy


P&W INDUSTRIAL PRODUCTS – Base Machine SelectionISO-BASELOAD POWER

Net output - kWNet output - kW

ST40-LECST40ST30ST18ST12ST6-81ST6-79ST6-72ST5

ST40-LECST40ST30ST18ST12ST6-81ST6-79ST6-72ST5

00 25002500200020001500150010001000500500

Current enginesCurrent enginesIn developmentIn development

30003000 35003500 40004000

4,0004,000

3,3003,300

1,8651,865

1,2001,200848848

680680508508

225 - 450225 - 450

4,0004,000

PlannedPlanned


Recuperator•Removable for integration with CHP and FC systems

Ported Inlet

LEC Combustor

ST5 Engine Package

Generator•gearless high speed generator by TGC

StarterFree Power Turbine•Improves turn down performance

Single stage compressor

Oil-free air bearing system


Base Engine is a High Efficiency MTG

8:1 Pressure ratio - aero based on PW207 but no common P/N• Redesigned for low cost production and operation

Convertible from recuperated (prime) to simple-cycle

@ shaft @ terminalsRated Power:

- ISO day, (59ºF) : 467kW 400kW- Hot day, (95ºF) : 390kW 333kW

Thermal efficiency- ηηηη recuperated : 34% 30%- ηηηη simple cycle: 24% 22%

Low emissions (base load natural gas fuel)- NOx < 10 ppm CO < 20 ppm UTC Distributed Generation Growth Path Aligned with DOE Goals


Simple Cycle Engines

Recuperated Cycle Engines

P&WC ENGINES – Proven Performance

Effic

ienc

y -%

Power rating (MW)0 54321

15

20

25

30

35

PGT2MAKILA T1

ST40

40

6 7 8 9 10

THM1203

THM1204GT2500CENTAUR 50

SB5SB15 SB30C

PGT5OP-16

SPW14

ST6-90

TYPHOON M

ST50

PGT 10Mars 90

AGT6000Tornado Tempest

GT6001

SB30E

Taurus 70

Typhoon 5.3

M7A-01Taurus 60LM500

TF40

ST30

CENTAUR 40

S2A-01

S1T-02S1A-02

DR 990 M7A-02

SATURN 20

TURMO III

Mercury 50

601KB9ASE120

ST18

501KB5

501KB7

ST6-72

ST6-79ST6-81

VT600

ST5

0.150.15

0.20.2

0.250.25

0.30.3

0.350.35

0.40.4

22 44 66 88 1010 1212 1414Pressure RatioPressure Ratio

Ther

mal

Effi

cien

cyTh

erm

al E

ffici

ency ST5

IncreasedRecuperator Dependence (risk)

Simple

Cycle

Pressure Ratio Selected toPressure Ratio Selected toPressure Ratio Selected toPressure Ratio Selected toDecrease Recuperator RiskDecrease Recuperator RiskDecrease Recuperator RiskDecrease Recuperator Risk

ST5

RecuperatedCycle

Mic

ro-t

urbi

nes

ST5 Design PointsST5 Recuperated Cycle parameters obtain:• best performance

• optimal choice of OPR + T4, with• balanced risk

• recuperator performance vs. specific power, and• achievable component life

• recuperator materials limits


Exhaust (70%)

Fuel In

Electricity (30%)Comp

Comb

Turb Gen

Recuperator

System combines performance and economics•PWC ST5 drives a 30% electrical efficiency microturbine system

• Recuperated gas turbine engine @ PR = 8• Exhaust flow @ 5 lb/s, ~700F

Right System Delivers Affordable Performance


Growth Strategy - Targets High System Efficiency

0.25

0.3

0.35

0.4

0.45

350 375 400 425 450 475 500ISO Baseload Electrical Power (kW)

Effic

ienc

y (%

ele

ctric

al)

Introductory Rating

Future (per DOE goals)•ceramic vane & turbine•bottoming cycle•reduced power losses , etc

Present Technology- scaled hardware- cooled vane- scaled generator


0.05

0.07

0.09

0.11

0.13

0.15

0.17

4.00 5.00 6.00 7.00 8.00 9.00

Fuel Cost ($/MMBtu)

Grid

Ele

ctric

ity C

ost (

$/kW

h)

MNTX

GA

AZ

MA

PA

CA

MI IL

NY

40% MicroturbineOHCT

VA FL

NJ

30% Microturbine

40% Microturbine CHP

Attractive economics for > 30% of US population• 4-year customer payback of installed equipment @ $700/kW• No credit taken for reliability, low emissions, or avoided transmission upgrade

Target 40% Microturbine Competitive in Many States

40% Microturbine


DOE Advanced Microturbine System Goals• Electrical efficiency = 40% • NOx = 7 PPM on natural gas fuel• Multi-fuel capability• 11,000 hour between major overhaul• System cost = $500US/kW

UTC Approach• Affordably increase P&W ST5-powered ENT400 microturbine from

30% to 40% electrical efficiency with NOx < 7 ppm•Demonstrate practical recuperated cycle•Improve selected component efficiency•Demonstrate bottoming cycle system efficiency

UTC Distributed Generation Growth Aligned with DOE Goals


Cycle improvement + Organic Rankine Cycle Improve System Efficiency• Hotter Engine: Efficiency gain = 3 points• Improved Electrical: Efficiency gain = 1 point• Recover Waste Heat: Efficiency gain = 7 points

GenTurb

CondenserPump

Vapor generator

Comp

Comb

Gen

Recuperator

Turb

Exhaust (60%)

Electricity (40%)

UTC Advanced Microturbine System: 3-Part Strategy


Organic Rankine Cycle (ORC) System

Engine Exhaust@ ~700°F

ORC Exhaust@ 150°F

Gen

VaporGenerator

Condenser

Liquid

Pump

Vapor

80 kW netTurb


Ceramics Used for Vane and Integrally-Bladed Rotor (IBR)

Government Labs/Companion Programs• ORNL-HTML – Characterizing silicon nitride materials, both with and without EBC• NASA-UEET– Developing high temperature EBC for CMC• Navy/DoE – Developing EBC for Silicon Nitride

Si3N4 IBRSaint Gobain (WB-NT154)

Integral Si3N4 VanesKyocera (SN282)


Fuel Staging to Sustain Low Emissions 70-100% Power

• NOx < 7 ppm and CO & UHC < 10 ppm

• Attained NOx, CO, and UHC < 9 ppm over ~75-100% power turndown

• Low pressure oscillations (<0.3 psi amplitude)achieved over turndown range

• Preferred staging strategyidentified for emissions and stability margin

T3=923F, P3=112 psia

0

0.1

0.2

0.3

0.4

0.5

0.6

2750 2800 2850 2900 2950 3000

Flame Temperature (F)

Equi

vale

nce

Rat

io ΦΦ ΦΦ

0

9

18

27

36

45

Equiv. RatioNOx

COUHC

7.0

Emis

sion

s at

15

% O

2 ( p

pm)

NOx Goal

Preliminary Tests Near 7 ppm NOx


Key Future Milestones Leading to Field Demonstration

2002! Demonstrate 80 kW from ORC (February 02 – Completed)• Demonstrate 5-point increase in system electrical efficiency with ORC (August 02)• Perform integrated microturbine/ORC test (September 02)• Demonstrate combustor emissions technology for NOx<7 ppm and CO<10 ppm

(November 02)2003• Demonstrate ceramic turbine performance in core engine (June 03)2004• Demonstrate 40% electrical efficiency, low NOx performance in engine

system (April 04)2005• Initiate >4000 hr field tests to demonstrate life (January 05)


What MTG is Right for a Fuel Cell Hybrid System?

• The right system must balance performance, cost, and risk• MTG must be profitable - the markets are still developing!

• Broad product applicability– Fired MTG and FC Hybrid– Integration options

• Affordable efficiency– Recuperator performance and life

• High system RAM - Reliability, Availability, Maintainability• Component and system stability under transients

Documents

Microturbine Generators for FC/MTG Hybrid Power Systems